Sample records for earthquake recurrence rates

  1. The Nazca-South American convergence rate and the recurrence of the great 1960 Chilean earthquake

    NASA Technical Reports Server (NTRS)

    Stein, S.; Engeln, J. F.; Demets, C.; Gordon, R. G.; Woods, D.

    1986-01-01

    The seismic slip rate along the Chile Trench estimated from the slip in the great 1960 earthquake and the recurrence history of major earthquakes has been interpreted as consistent with the subduction rate of the Nazca plate beneath South America. The convergence rate, estimated from global relative plate motion models, depends significantly on closure of the Nazca - Antarctica - South America circuit. NUVEL-1, a new plate motion model which incorporates recently determined spreading rates on the Chile Rise, shows that the average convergence rate over the last three million years is slower than previously estimated. If this time-averaged convergence rate provides an appropriate upper bound for the seismic slip rate, either the characteristic Chilean subduction earthquake is smaller than the 1960 event, the average recurrence interval is greater than observed in the last 400 years, or both. These observations bear out the nonuniformity of plate motions on various time scales, the variability in characteristic subduction zone earthquake size, and the limitations of recurrence time estimates.

  2. Laboratory constraints on models of earthquake recurrence

    NASA Astrophysics Data System (ADS)

    Beeler, N. M.; Tullis, Terry; Junger, Jenni; Kilgore, Brian; Goldsby, David

    2014-12-01

    In this study, rock friction "stick-slip" experiments are used to develop constraints on models of earthquake recurrence. Constant rate loading of bare rock surfaces in high-quality experiments produces stick-slip recurrence that is periodic at least to second order. When the loading rate is varied, recurrence is approximately inversely proportional to loading rate. These laboratory events initiate due to a slip-rate-dependent process that also determines the size of the stress drop and, as a consequence, stress drop varies weakly but systematically with loading rate. This is especially evident in experiments where the loading rate is changed by orders of magnitude, as is thought to be the loading condition of naturally occurring, small repeating earthquakes driven by afterslip, or low-frequency earthquakes loaded by episodic slip. The experimentally observed stress drops are well described by a logarithmic dependence on recurrence interval that can be cast as a nonlinear slip predictable model. The fault's rate dependence of strength is the key physical parameter. Additionally, even at constant loading rate the most reproducible laboratory recurrence is not exactly periodic, unlike existing friction recurrence models. We present example laboratory catalogs that document the variance and show that in large catalogs, even at constant loading rate, stress drop and recurrence covary systematically. The origin of this covariance is largely consistent with variability of the dependence of fault strength on slip rate. Laboratory catalogs show aspects of both slip and time predictability, and successive stress drops are strongly correlated indicating a "memory" of prior slip history that extends over at least one recurrence cycle.

  3. Laboratory constraints on models of earthquake recurrence

    USGS Publications Warehouse

    Beeler, Nicholas M.; Tullis, Terry; Junger, Jenni; Kilgore, Brian D.; Goldsby, David L.

    2014-01-01

    In this study, rock friction ‘stick-slip’ experiments are used to develop constraints on models of earthquake recurrence. Constant-rate loading of bare rock surfaces in high quality experiments produces stick-slip recurrence that is periodic at least to second order. When the loading rate is varied, recurrence is approximately inversely proportional to loading rate. These laboratory events initiate due to a slip rate-dependent process that also determines the size of the stress drop [Dieterich, 1979; Ruina, 1983] and as a consequence, stress drop varies weakly but systematically with loading rate [e.g., Gu and Wong, 1991; Karner and Marone, 2000; McLaskey et al., 2012]. This is especially evident in experiments where the loading rate is changed by orders of magnitude, as is thought to be the loading condition of naturally occurring, small repeating earthquakes driven by afterslip, or low-frequency earthquakes loaded by episodic slip. As follows from the previous studies referred to above, experimentally observed stress drops are well described by a logarithmic dependence on recurrence interval that can be cast as a non-linear slip-predictable model. The fault’s rate dependence of strength is the key physical parameter. Additionally, even at constant loading rate the most reproducible laboratory recurrence is not exactly periodic, unlike existing friction recurrence models. We present example laboratory catalogs that document the variance and show that in large catalogs, even at constant loading rate, stress drop and recurrence co-vary systematically. The origin of this covariance is largely consistent with variability of the dependence of fault strength on slip rate. Laboratory catalogs show aspects of both slip and time predictability and successive stress drops are strongly correlated indicating a ‘memory’ of prior slip history that extends over at least one recurrence cycle.

  4. Earthquakes: Recurrence and Interoccurrence Times

    NASA Astrophysics Data System (ADS)

    Abaimov, S. G.; Turcotte, D. L.; Shcherbakov, R.; Rundle, J. B.; Yakovlev, G.; Goltz, C.; Newman, W. I.

    2008-04-01

    The purpose of this paper is to discuss the statistical distributions of recurrence times of earthquakes. Recurrence times are the time intervals between successive earthquakes at a specified location on a specified fault. Although a number of statistical distributions have been proposed for recurrence times, we argue in favor of the Weibull distribution. The Weibull distribution is the only distribution that has a scale-invariant hazard function. We consider three sets of characteristic earthquakes on the San Andreas fault: (1) The Parkfield earthquakes, (2) the sequence of earthquakes identified by paleoseismic studies at the Wrightwood site, and (3) an example of a sequence of micro-repeating earthquakes at a site near San Juan Bautista. In each case we make a comparison with the applicable Weibull distribution. The number of earthquakes in each of these sequences is too small to make definitive conclusions. To overcome this difficulty we consider a sequence of earthquakes obtained from a one million year “Virtual California” simulation of San Andreas earthquakes. Very good agreement with a Weibull distribution is found. We also obtain recurrence statistics for two other model studies. The first is a modified forest-fire model and the second is a slider-block model. In both cases good agreements with Weibull distributions are obtained. Our conclusion is that the Weibull distribution is the preferred distribution for estimating the risk of future earthquakes on the San Andreas fault and elsewhere.

  5. A physically-based earthquake recurrence model for estimation of long-term earthquake probabilities

    USGS Publications Warehouse

    Ellsworth, William L.; Matthews, Mark V.; Nadeau, Robert M.; Nishenko, Stuart P.; Reasenberg, Paul A.; Simpson, Robert W.

    1999-01-01

    A physically-motivated model for earthquake recurrence based on the Brownian relaxation oscillator is introduced. The renewal process defining this point process model can be described by the steady rise of a state variable from the ground state to failure threshold as modulated by Brownian motion. Failure times in this model follow the Brownian passage time (BPT) distribution, which is specified by the mean time to failure, μ, and the aperiodicity of the mean, α (equivalent to the familiar coefficient of variation). Analysis of 37 series of recurrent earthquakes, M -0.7 to 9.2, suggests a provisional generic value of α = 0.5. For this value of α, the hazard function (instantaneous failure rate of survivors) exceeds the mean rate for times > μ⁄2, and is ~ ~ 2 ⁄ μ for all times > μ. Application of this model to the next M 6 earthquake on the San Andreas fault at Parkfield, California suggests that the annual probability of the earthquake is between 1:10 and 1:13.

  6. A Brownian model for recurrent earthquakes

    USGS Publications Warehouse

    Matthews, M.V.; Ellsworth, W.L.; Reasenberg, P.A.

    2002-01-01

    We construct a probability model for rupture times on a recurrent earthquake source. Adding Brownian perturbations to steady tectonic loading produces a stochastic load-state process. Rupture is assumed to occur when this process reaches a critical-failure threshold. An earthquake relaxes the load state to a characteristic ground level and begins a new failure cycle. The load-state process is a Brownian relaxation oscillator. Intervals between events have a Brownian passage-time distribution that may serve as a temporal model for time-dependent, long-term seismic forecasting. This distribution has the following noteworthy properties: (1) the probability of immediate rerupture is zero; (2) the hazard rate increases steadily from zero at t = 0 to a finite maximum near the mean recurrence time and then decreases asymptotically to a quasi-stationary level, in which the conditional probability of an event becomes time independent; and (3) the quasi-stationary failure rate is greater than, equal to, or less than the mean failure rate because the coefficient of variation is less than, equal to, or greater than 1/???2 ??? 0.707. In addition, the model provides expressions for the hazard rate and probability of rupture on faults for which only a bound can be placed on the time of the last rupture. The Brownian relaxation oscillator provides a connection between observable event times and a formal state variable that reflects the macromechanics of stress and strain accumulation. Analysis of this process reveals that the quasi-stationary distance to failure has a gamma distribution, and residual life has a related exponential distribution. It also enables calculation of "interaction" effects due to external perturbations to the state, such as stress-transfer effects from earthquakes outside the target source. The influence of interaction effects on recurrence times is transient and strongly dependent on when in the loading cycle step pertubations occur. Transient effects may

  7. Earthquake recurrence models fail when earthquakes fail to reset the stress field

    USGS Publications Warehouse

    Tormann, Thessa; Wiemer, Stefan; Hardebeck, Jeanne L.

    2012-01-01

    Parkfield's regularly occurring M6 mainshocks, about every 25 years, have over two decades stoked seismologists' hopes to successfully predict an earthquake of significant size. However, with the longest known inter-event time of 38 years, the latest M6 in the series (28 Sep 2004) did not conform to any of the applied forecast models, questioning once more the predictability of earthquakes in general. Our study investigates the spatial pattern of b-values along the Parkfield segment through the seismic cycle and documents a stably stressed structure. The forecasted rate of M6 earthquakes based on Parkfield's microseismicity b-values corresponds well to observed rates. We interpret the observed b-value stability in terms of the evolution of the stress field in that area: the M6 Parkfield earthquakes do not fully unload the stress on the fault, explaining why time recurrent models fail. We present the 1989 M6.9 Loma Prieta earthquake as counter example, which did release a significant portion of the stress along its fault segment and yields a substantial change in b-values.

  8. Geological and historical evidence of irregular recurrent earthquakes in Japan.

    PubMed

    Satake, Kenji

    2015-10-28

    Great (M∼8) earthquakes repeatedly occur along the subduction zones around Japan and cause fault slip of a few to several metres releasing strains accumulated from decades to centuries of plate motions. Assuming a simple 'characteristic earthquake' model that similar earthquakes repeat at regular intervals, probabilities of future earthquake occurrence have been calculated by a government committee. However, recent studies on past earthquakes including geological traces from giant (M∼9) earthquakes indicate a variety of size and recurrence interval of interplate earthquakes. Along the Kuril Trench off Hokkaido, limited historical records indicate that average recurrence interval of great earthquakes is approximately 100 years, but the tsunami deposits show that giant earthquakes occurred at a much longer interval of approximately 400 years. Along the Japan Trench off northern Honshu, recurrence of giant earthquakes similar to the 2011 Tohoku earthquake with an interval of approximately 600 years is inferred from historical records and tsunami deposits. Along the Sagami Trough near Tokyo, two types of Kanto earthquakes with recurrence interval of a few hundred years and a few thousand years had been recognized, but studies show that the recent three Kanto earthquakes had different source extents. Along the Nankai Trough off western Japan, recurrence of great earthquakes with an interval of approximately 100 years has been identified from historical literature, but tsunami deposits indicate that the sizes of the recurrent earthquakes are variable. Such variability makes it difficult to apply a simple 'characteristic earthquake' model for the long-term forecast, and several attempts such as use of geological data for the evaluation of future earthquake probabilities or the estimation of maximum earthquake size in each subduction zone are being conducted by government committees. © 2015 The Author(s).

  9. Rescaled earthquake recurrence time statistics: application to microrepeaters

    NASA Astrophysics Data System (ADS)

    Goltz, Christian; Turcotte, Donald L.; Abaimov, Sergey G.; Nadeau, Robert M.; Uchida, Naoki; Matsuzawa, Toru

    2009-01-01

    Slip on major faults primarily occurs during `characteristic' earthquakes. The recurrence statistics of characteristic earthquakes play an important role in seismic hazard assessment. A major problem in determining applicable statistics is the short sequences of characteristic earthquakes that are available worldwide. In this paper, we introduce a rescaling technique in which sequences can be superimposed to establish larger numbers of data points. We consider the Weibull and log-normal distributions, in both cases we rescale the data using means and standard deviations. We test our approach utilizing sequences of microrepeaters, micro-earthquakes which recur in the same location on a fault. It seems plausible to regard these earthquakes as a miniature version of the classic characteristic earthquakes. Microrepeaters are much more frequent than major earthquakes, leading to longer sequences for analysis. In this paper, we present results for the analysis of recurrence times for several microrepeater sequences from Parkfield, CA as well as NE Japan. We find that, once the respective sequence can be considered to be of sufficient stationarity, the statistics can be well fitted by either a Weibull or a log-normal distribution. We clearly demonstrate this fact by our technique of rescaled combination. We conclude that the recurrence statistics of the microrepeater sequences we consider are similar to the recurrence statistics of characteristic earthquakes on major faults.

  10. Universal Recurrence Time Statistics of Characteristic Earthquakes

    NASA Astrophysics Data System (ADS)

    Goltz, C.; Turcotte, D. L.; Abaimov, S.; Nadeau, R. M.

    2006-12-01

    Characteristic earthquakes are defined to occur quasi-periodically on major faults. Do recurrence time statistics of such earthquakes follow a particular statistical distribution? If so, which one? The answer is fundamental and has important implications for hazard assessment. The problem cannot be solved by comparing the goodness of statistical fits as the available sequences are too short. The Parkfield sequence of M ≍ 6 earthquakes, one of the most extensive reliable data sets available, has grown to merely seven events with the last earthquake in 2004, for example. Recently, however, advances in seismological monitoring and improved processing methods have unveiled so-called micro-repeaters, micro-earthquakes which recur exactly in the same location on a fault. It seems plausible to regard these earthquakes as a miniature version of the classic characteristic earthquakes. Micro-repeaters are much more frequent than major earthquakes, leading to longer sequences for analysis. Due to their recent discovery, however, available sequences contain less than 20 events at present. In this paper we present results for the analysis of recurrence times for several micro-repeater sequences from Parkfield and adjacent regions. To improve the statistical significance of our findings, we combine several sequences into one by rescaling the individual sets by their respective mean recurrence intervals and Weibull exponents. This novel approach of rescaled combination yields the most extensive data set possible. We find that the resulting statistics can be fitted well by an exponential distribution, confirming the universal applicability of the Weibull distribution to characteristic earthquakes. A similar result is obtained from rescaled combination, however, with regard to the lognormal distribution.

  11. Earthquake Clustering on Normal Faults: Insight from Rate-and-State Friction Models

    NASA Astrophysics Data System (ADS)

    Biemiller, J.; Lavier, L. L.; Wallace, L.

    2016-12-01

    Temporal variations in slip rate on normal faults have been recognized in Hawaii and the Basin and Range. The recurrence intervals of these slip transients range from 2 years on the flanks of Kilauea, Hawaii to 10 kyr timescale earthquake clustering on the Wasatch Fault in the eastern Basin and Range. In addition to these longer recurrence transients in the Basin and Range, recent GPS results there also suggest elevated deformation rate events with recurrence intervals of 2-4 years. These observations suggest that some active normal fault systems are dominated by slip behaviors that fall between the end-members of steady aseismic creep and periodic, purely elastic, seismic-cycle deformation. Recent studies propose that 200 year to 50 kyr timescale supercycles may control the magnitude, timing, and frequency of seismic-cycle earthquakes in subduction zones, where aseismic slip transients are known to play an important role in total deformation. Seismic cycle deformation of normal faults may be similarly influenced by its timing within long-period supercycles. We present numerical models (based on rate-and-state friction) of normal faults such as the Wasatch Fault showing that realistic rate-and-state parameter distributions along an extensional fault zone can give rise to earthquake clusters separated by 500 yr - 5 kyr periods of aseismic slip transients on some portions of the fault. The recurrence intervals of events within each earthquake cluster range from 200 to 400 years. Our results support the importance of stress and strain history as controls on a normal fault's present and future slip behavior and on the characteristics of its current seismic cycle. These models suggest that long- to medium-term fault slip history may influence the temporal distribution, recurrence interval, and earthquake magnitudes for a given normal fault segment.

  12. Chilean megathrust earthquake recurrence linked to frictional contrast at depth

    NASA Astrophysics Data System (ADS)

    Moreno, M.; Li, S.; Melnick, D.; Bedford, J. R.; Baez, J. C.; Motagh, M.; Metzger, S.; Vajedian, S.; Sippl, C.; Gutknecht, B. D.; Contreras-Reyes, E.; Deng, Z.; Tassara, A.; Oncken, O.

    2018-04-01

    Fundamental processes of the seismic cycle in subduction zones, including those controlling the recurrence and size of great earthquakes, are still poorly understood. Here, by studying the 2016 earthquake in southern Chile—the first large event within the rupture zone of the 1960 earthquake (moment magnitude (Mw) = 9.5)—we show that the frictional zonation of the plate interface fault at depth mechanically controls the timing of more frequent, moderate-size deep events (Mw < 8) and less frequent, tsunamigenic great shallow earthquakes (Mw > 8.5). We model the evolution of stress build-up for a seismogenic zone with heterogeneous friction to examine the link between the 2016 and 1960 earthquakes. Our results suggest that the deeper segments of the seismogenic megathrust are weaker and interseismically loaded by a more strongly coupled, shallower asperity. Deeper segments fail earlier ( 60 yr recurrence), producing moderate-size events that precede the failure of the shallower region, which fails in a great earthquake (recurrence >110 yr). We interpret the contrasting frictional strength and lag time between deeper and shallower earthquakes to be controlled by variations in pore fluid pressure. Our integrated analysis strengthens understanding of the mechanics and timing of great megathrust earthquakes, and therefore could aid in the seismic hazard assessment of other subduction zones.

  13. Periodic, chaotic, and doubled earthquake recurrence intervals on the deep San Andreas Fault

    USGS Publications Warehouse

    Shelly, David R.

    2010-01-01

    Earthquake recurrence histories may provide clues to the timing of future events, but long intervals between large events obscure full recurrence variability. In contrast, small earthquakes occur frequently, and recurrence intervals are quantifiable on a much shorter time scale. In this work, I examine an 8.5-year sequence of more than 900 recurring low-frequency earthquake bursts composing tremor beneath the San Andreas fault near Parkfield, California. These events exhibit tightly clustered recurrence intervals that, at times, oscillate between ~3 and ~6 days, but the patterns sometimes change abruptly. Although the environments of large and low-frequency earthquakes are different, these observations suggest that similar complexity might underlie sequences of large earthquakes.

  14. Quasi-periodic recurrence of large earthquakes on the southern San Andreas fault

    USGS Publications Warehouse

    Scharer, Katherine M.; Biasi, Glenn P.; Weldon, Ray J.; Fumal, Tom E.

    2010-01-01

    It has been 153 yr since the last large earthquake on the southern San Andreas fault (California, United States), but the average interseismic interval is only ~100 yr. If the recurrence of large earthquakes is periodic, rather than random or clustered, the length of this period is notable and would generally increase the risk estimated in probabilistic seismic hazard analyses. Unfortunately, robust characterization of a distribution describing earthquake recurrence on a single fault is limited by the brevity of most earthquake records. Here we use statistical tests on a 3000 yr combined record of 29 ground-rupturing earthquakes from Wrightwood, California. We show that earthquake recurrence there is more regular than expected from a Poisson distribution and is not clustered, leading us to conclude that recurrence is quasi-periodic. The observation of unimodal time dependence is persistent across an observationally based sensitivity analysis that critically examines alternative interpretations of the geologic record. The results support formal forecast efforts that use renewal models to estimate probabilities of future earthquakes on the southern San Andreas fault. Only four intervals (15%) from the record are longer than the present open interval, highlighting the current hazard posed by this fault.

  15. GPS constraints on M 7-8 earthquake recurrence times for the New Madrid seismic zone

    USGS Publications Warehouse

    Stuart, W.D.

    2001-01-01

    Newman et al. (1999) estimate the time interval between the 1811-1812 earthquake sequence near New Madrid, Missouri and a future similar sequence to be at least 2,500 years, an interval significantly longer than other recently published estimates. To calculate the recurrence time, they assume that slip on a vertical half-plane at depth contributes to the current interseismic motion of GPS benchmarks. Compared to other plausible fault models, the half-plane model gives nearly the maximum rate of ground motion for the same interseismic slip rate. Alternative models with smaller interseismic fault slip area can satisfy the present GPS data by having higher slip rate and thus can have earthquake recurrence times much less than 2,500 years.

  16. Estimation of recurrence interval of large earthquakes on the central Longmen Shan fault zone based on seismic moment accumulation/release model.

    PubMed

    Ren, Junjie; Zhang, Shimin

    2013-01-01

    Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 10¹⁷ N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region.

  17. Estimation of Recurrence Interval of Large Earthquakes on the Central Longmen Shan Fault Zone Based on Seismic Moment Accumulation/Release Model

    PubMed Central

    Zhang, Shimin

    2013-01-01

    Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 1017 N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region. PMID:23878524

  18. Slip rate and earthquake recurrence along the central Septentrional fault, North American-Caribbean plate boundary, Dominican Republic

    USGS Publications Warehouse

    Prentice, C.S.; Mann, P.; Pena, L.R.; Burr, G.

    2003-01-01

    The Septentrional fault zone (SFZ) is the major North American-Caribbean, strike-slip, plate boundary fault at the longitude of eastern Hispaniola. The SFZ traverses the densely populated Cibao Valley of the Dominican Republic, forming a prominent scarp in alluvium. Our studies at four sites along the central SFZ are aimed at quantifying the late Quaternary behavior of this structure to better understand the seismic hazard it represents for the northeastern Caribbean. Our investigations of excavations at sites near Rio Cenovi show that the most recent ground-rupturing earthquake along this fault in the north central Dominican Republic occurred between A.D. 1040 and A.D. 1230, and involved a minimum of ???4 m of left-lateral slip and 2.3 m of normal dip slip at that site. Our studies of offset stream terraces at two locations, Rio Juan Lopez and Rio Licey, provide late Holocene slip rate estimates of 6-9 mm/yr and a maximum of 11-12 mm/yr, respectively, across the Septentrional fault. Combining these results gives a best estimate of 6-12 mm/yr for the slip rate across the SFZ. Three excavations, two near Tenares and one at the Rio Licey site, yielded evidence for the occurrence of earlier prehistoric earthquakes. Dates of strata associated with the penultimate event suggest that it occurred post-A.D. 30, giving a recurrence interval of 800-1200 years. These studies indicate that the SFZ has likely accumulated elastic strain sufficient to generate a major earthquake during the more than 800 years since it last slipped and should be considered likely to produce a destructive future earthquake.

  19. Fixed recurrence and slip models better predict earthquake behavior than the time- and slip-predictable models 1: repeating earthquakes

    USGS Publications Warehouse

    Rubinstein, Justin L.; Ellsworth, William L.; Chen, Kate Huihsuan; Uchida, Naoki

    2012-01-01

    The behavior of individual events in repeating earthquake sequences in California, Taiwan and Japan is better predicted by a model with fixed inter-event time or fixed slip than it is by the time- and slip-predictable models for earthquake occurrence. Given that repeating earthquakes are highly regular in both inter-event time and seismic moment, the time- and slip-predictable models seem ideally suited to explain their behavior. Taken together with evidence from the companion manuscript that shows similar results for laboratory experiments we conclude that the short-term predictions of the time- and slip-predictable models should be rejected in favor of earthquake models that assume either fixed slip or fixed recurrence interval. This implies that the elastic rebound model underlying the time- and slip-predictable models offers no additional value in describing earthquake behavior in an event-to-event sense, but its value in a long-term sense cannot be determined. These models likely fail because they rely on assumptions that oversimplify the earthquake cycle. We note that the time and slip of these events is predicted quite well by fixed slip and fixed recurrence models, so in some sense they are time- and slip-predictable. While fixed recurrence and slip models better predict repeating earthquake behavior than the time- and slip-predictable models, we observe a correlation between slip and the preceding recurrence time for many repeating earthquake sequences in Parkfield, California. This correlation is not found in other regions, and the sequences with the correlative slip-predictable behavior are not distinguishable from nearby earthquake sequences that do not exhibit this behavior.

  20. Viscoelasticity, postseismic slip, fault interactions, and the recurrence of large earthquakes

    USGS Publications Warehouse

    Michael, A.J.

    2005-01-01

    The Brownian Passage Time (BPT) model for earthquake recurrence is modified to include transient deformation due to either viscoelasticity or deep post seismic slip. Both of these processes act to increase the rate of loading on the seismogenic fault for some time after a large event. To approximate these effects, a decaying exponential term is added to the BPT model's uniform loading term. The resulting interevent time distributions remain approximately lognormal, but the balance between the level of noise (e.g., unknown fault interactions) and the coefficient of variability of the interevent time distribution changes depending on the shape of the loading function. For a given level of noise in the loading process, transient deformation has the effect of increasing the coefficient of variability of earthquake interevent times. Conversely, the level of noise needed to achieve a given level of variability is reduced when transient deformation is included. Using less noise would then increase the effect of known fault interactions modeled as stress or strain steps because they would be larger with respect to the noise. If we only seek to estimate the shape of the interevent time distribution from observed earthquake occurrences, then the use of a transient deformation model will not dramatically change the results of a probability study because a similar shaped distribution can be achieved with either uniform or transient loading functions. However, if the goal is to estimate earthquake probabilities based on our increasing understanding of the seismogenic process, including earthquake interactions, then including transient deformation is important to obtain accurate results. For example, a loading curve based on the 1906 earthquake, paleoseismic observations of prior events, and observations of recent deformation in the San Francisco Bay region produces a 40% greater variability in earthquake recurrence than a uniform loading model with the same noise level.

  1. Large earthquake rates from geologic, geodetic, and seismological perspectives

    NASA Astrophysics Data System (ADS)

    Jackson, D. D.

    2017-12-01

    Earthquake rate and recurrence information comes primarily from geology, geodesy, and seismology. Geology gives the longest temporal perspective, but it reveals only surface deformation, relatable to earthquakes only with many assumptions. Geodesy is also limited to surface observations, but it detects evidence of the processes leading to earthquakes, again subject to important assumptions. Seismology reveals actual earthquakes, but its history is too short to capture important properties of very large ones. Unfortunately, the ranges of these observation types barely overlap, so that integrating them into a consistent picture adequate to infer future prospects requires a great deal of trust. Perhaps the most important boundary is the temporal one at the beginning of the instrumental seismic era, about a century ago. We have virtually no seismological or geodetic information on large earthquakes before then, and little geological information after. Virtually all-modern forecasts of large earthquakes assume some form of equivalence between tectonic- and seismic moment rates as functions of location, time, and magnitude threshold. That assumption links geology, geodesy, and seismology, but it invokes a host of other assumptions and incurs very significant uncertainties. Questions include temporal behavior of seismic and tectonic moment rates; shape of the earthquake magnitude distribution; upper magnitude limit; scaling between rupture length, width, and displacement; depth dependence of stress coupling; value of crustal rigidity; and relation between faults at depth and their surface fault traces, to name just a few. In this report I'll estimate the quantitative implications for estimating large earthquake rate. Global studies like the GEAR1 project suggest that surface deformation from geology and geodesy best show the geography of very large, rare earthquakes in the long term, while seismological observations of small earthquakes best forecasts moderate earthquakes

  2. Constraining the Long-Term Average of Earthquake Recurrence Intervals From Paleo- and Historic Earthquakes by Assimilating Information From Instrumental Seismicity

    NASA Astrophysics Data System (ADS)

    Zoeller, G.

    2017-12-01

    Paleo- and historic earthquakes are the most important source of information for the estimationof long-term recurrence intervals in fault zones, because sequences of paleoearthquakes cover more than one seismic cycle. On the other hand, these events are often rare, dating uncertainties are enormous and the problem of missing or misinterpreted events leads to additional problems. Taking these shortcomings into account, long-term recurrence intervals are usually unstable as long as no additional information are included. In the present study, we assume that the time to the next major earthquake depends on the rate of small and intermediate events between the large ones in terms of a ``clock-change'' model that leads to a Brownian Passage Time distribution for recurrence intervals. We take advantage of an earlier finding that the aperiodicity of this distribution can be related to the Gutenberg-Richter-b-value, which is usually around one and can be estimated easily from instrumental seismicity in the region under consideration. This allows to reduce the uncertainties in the estimation of the mean recurrence interval significantly, especially for short paleoearthquake sequences and high dating uncertainties. We present illustrative case studies from Southern California and compare the method with the commonly used approach of exponentially distributed recurrence times assuming a stationary Poisson process.

  3. How Long Is Long Enough? Estimation of Slip-Rate and Earthquake Recurrence Interval on a Simple Plate-Boundary Fault Using 3D Paleoseismic Trenching

    NASA Astrophysics Data System (ADS)

    Wechsler, N.; Rockwell, T. K.; Klinger, Y.; Agnon, A.; Marco, S.

    2012-12-01

    Models used to forecast future seismicity make fundamental assumptions about the behavior of faults and fault systems in the long term, but in many cases this long-term behavior is assumed using short-term and perhaps non-representative observations. The question arises - how long of a record is long enough to represent actual fault behavior, both in terms of recurrence of earthquakes and of moment release (aka slip-rate). We test earthquake recurrence and slip models via high-resolution three-dimensional trenching of the Beteiha (Bet-Zayda) site on the Dead Sea Transform (DST) in northern Israel. We extend the earthquake history of this simple plate boundary fault to establish slip rate for the past 3-4kyr, to determine the amount of slip per event and to study the fundamental behavior, thereby testing competing rupture models (characteristic, slip-patch, slip-loading, and Gutenberg Richter type distribution). To this end we opened more than 900m of trenches, mapped 8 buried channels and dated more than 80 radiocarbon samples. By mapping buried channels, offset by the DST on both sides of the fault, we obtained for each an estimate of displacement. Coupled with fault crossing trenches to determine event history, we construct earthquake and slip history for the fault for the past 2kyr. We observe evidence for a total of 9-10 surface-rupturing earthquakes with varying offset amounts. 6-7 events occurred in the 1st millennium, compared to just 2-3 in the 2nd millennium CE. From our observations it is clear that the fault is not behaving in a periodic fashion. A 4kyr old buried channel yields a slip rate of 3.5-4mm/yr, consistent with GPS rates for this segment. Yet in spite of the apparent agreement between GPS, Pleistocene to present slip rate, and the lifetime rate of the DST, the past 800-1000 year period appears deficit in strain release. Thus, in terms of moment release, most of the fault has remained locked and is accumulating elastic strain. In contrast, the

  4. Seismic Regionalization of Michoacan, Mexico and Recurrence Periods for Earthquakes

    NASA Astrophysics Data System (ADS)

    Magaña García, N.; Figueroa-Soto, Á.; Garduño-Monroy, V. H.; Zúñiga, R.

    2017-12-01

    Michoacán is one of the states with the highest occurrence of earthquakes in Mexico and it is a limit of convergence triggered by the subduction of Cocos plate over the North American plate, located in the zone of the Pacific Ocean of our country, in addition to the existence of active faults inside of the state like the Morelia-Acambay Fault System (MAFS).It is important to make a combination of seismic, paleosismological and geological studies to have good planning and development of urban complexes to mitigate disasters if destructive earthquakes appear. With statistical seismology it is possible to characterize the degree of seismic activity as well as to estimate the recurrence periods for earthquakes. For this work, seismicity catalog of Michoacán was compiled and homogenized in time and magnitude. This information was obtained from world and national agencies (SSN, CMT, etc), some data published by Mendoza and Martínez-López (2016) and starting from the seismic catalog homogenized by F. R. Zúñiga (Personal communication). From the analysis of the different focal mechanisms reported in the literature and geological studies, the seismic regionalization of the state of Michoacán complemented the one presented by Vázquez-Rosas (2012) and the recurrence periods for earthquakes within the four different seismotectonic regions. In addition, stable periods were determined for the b value of the Gutenberg-Richter (1944) using the Maximum Curvature and EMR (Entire Magnitude Range Method, 2005) techniques, which allowed us to determine recurrence periods: years for earthquakes upper to 7.5 for the subduction zone (A zone) with EMR technique and years with MAXC technique for the same years for earthquakes upper to 5 for B1 zone with EMR technique and years with MAXC technique; years for earthquakes upper to 7.0 for B2 zone with EMR technique and years with MAXC technique; and the last one, the Morelia-Acambay Fault Sistem zone (C zone) years for earthquakes

  5. Silica precipitation potentially controls earthquake recurrence in seismogenic zones.

    PubMed

    Saishu, Hanae; Okamoto, Atsushi; Otsubo, Makoto

    2017-10-17

    Silica precipitation is assumed to play a significant role in post-earthquake recovery of the mechanical and hydrological properties of seismogenic zones. However, the relationship between the widespread quartz veins around seismogenic zones and earthquake recurrence is poorly understood. Here we propose a novel model of quartz vein formation associated with fluid advection from host rocks and silica precipitation in a crack, in order to quantify the timescale of crack sealing. When applied to sets of extensional quartz veins around the Nobeoka Thrust of SW Japan, an ancient seismogenic splay fault, our model indicates that a fluid pressure drop of 10-25 MPa facilitates the formation of typical extensional quartz veins over a period of 6.6 × 10 0 -5.6 × 10 1 years, and that 89%-100% of porosity is recovered within ~3 × 10 2 years. The former and latter sealing timescales correspond to the extensional stress period (~3 × 10 1 years) and the recurrence interval of megaearthquakes in the Nankai Trough (~3 × 10 2 years), respectively. We therefore suggest that silica precipitation in the accretionary wedge controls the recurrence interval of large earthquakes in subduction zones.

  6. M ≥ 7.0 earthquake recurrence on the San Andreas fault from a stress renewal model

    USGS Publications Warehouse

    Parsons, Thomas E.

    2006-01-01

     Forecasting M ≥ 7.0 San Andreas fault earthquakes requires an assessment of their expected frequency. I used a three-dimensional finite element model of California to calculate volumetric static stress drops from scenario M ≥ 7.0 earthquakes on three San Andreas fault sections. The ratio of stress drop to tectonic stressing rate derived from geodetic displacements yielded recovery times at points throughout the model volume. Under a renewal model, stress recovery times on ruptured fault planes can be a proxy for earthquake recurrence. I show curves of magnitude versus stress recovery time for three San Andreas fault sections. When stress recovery times were converted to expected M ≥ 7.0 earthquake frequencies, they fit Gutenberg-Richter relationships well matched to observed regional rates of M ≤ 6.0 earthquakes. Thus a stress-balanced model permits large earthquake Gutenberg-Richter behavior on an individual fault segment, though it does not require it. Modeled slip magnitudes and their expected frequencies were consistent with those observed at the Wrightwood paleoseismic site if strict time predictability does not apply to the San Andreas fault.

  7. Wrightwood and the earthquake cycle: What a long recurrence record tells us about how faults work

    USGS Publications Warehouse

    Weldon, R.; Scharer, K.; Fumal, T.; Biasi, G.

    2004-01-01

    The concept of the earthquake cycle is so well established that one often hears statements in the popular media like, "the Big One is overdue" and "the longer it waits, the bigger it will be." Surprisingly, data to critically test the variability in recurrence intervals, rupture displacements, and relationships between the two are almost nonexistent. To generate a long series of earthquake intervals and offsets, we have conducted paleoseismic investigations across the San Andreas fault near the town of Wrightwood, California, excavating 45 trenches over 18 years, and can now provide some answers to basic questions about recurrence behavior of large earthquakes. To date, we have characterized at least 30 prehistoric earthquakes in a 6000-yr-long record, complete for the past 1500 yr and for the interval 3000-1500 B.C. For the past 1500 yr, the mean recurrence interval is 105 yr (31-165 yr for individual intervals) and the mean slip is 3.2 m (0.7-7 m per event). The series is slightly more ordered than random and has a notable cluster of events, during which strain was released at 3 times the long-term average rate. Slip associated with an earthquake is not well predicted by the interval preceding it, and only the largest two earthquakes appear to affect the time interval to the next earthquake. Generally, short intervals tend to coincide with large displacements and long intervals with small displacements. The most significant correlation we find is that earthquakes are more frequent following periods of net strain accumulation spanning multiple seismic cycles. The extent of paleoearthquake ruptures may be inferred by correlating event ages between different sites along the San Andreas fault. Wrightwood and other nearby sites experience rupture that could be attributed to overlap of relatively independent segments that each behave in a more regular manner. However, the data are equally consistent with a model in which the irregular behavior seen at Wrightwood

  8. Fixed recurrence and slip models better predict earthquake behavior than the time- and slip-predictable models: 2. Laboratory earthquakes

    NASA Astrophysics Data System (ADS)

    Rubinstein, Justin L.; Ellsworth, William L.; Beeler, Nicholas M.; Kilgore, Brian D.; Lockner, David A.; Savage, Heather M.

    2012-02-01

    The behavior of individual stick-slip events observed in three different laboratory experimental configurations is better explained by a "memoryless" earthquake model with fixed inter-event time or fixed slip than it is by the time- and slip-predictable models for earthquake occurrence. We make similar findings in the companion manuscript for the behavior of natural repeating earthquakes. Taken together, these results allow us to conclude that the predictions of a characteristic earthquake model that assumes either fixed slip or fixed recurrence interval should be preferred to the predictions of the time- and slip-predictable models for all earthquakes. Given that the fixed slip and recurrence models are the preferred models for all of the experiments we examine, we infer that in an event-to-event sense the elastic rebound model underlying the time- and slip-predictable models does not explain earthquake behavior. This does not indicate that the elastic rebound model should be rejected in a long-term-sense, but it should be rejected for short-term predictions. The time- and slip-predictable models likely offer worse predictions of earthquake behavior because they rely on assumptions that are too simple to explain the behavior of earthquakes. Specifically, the time-predictable model assumes a constant failure threshold and the slip-predictable model assumes that there is a constant minimum stress. There is experimental and field evidence that these assumptions are not valid for all earthquakes.

  9. Paleoseismic Evidence for Recurrence of Earthquakes near Charleston, South Carolina

    NASA Astrophysics Data System (ADS)

    Talwani, Pradeep; Cox, John

    1985-07-01

    A destructive earthquake that occurred in 1886 near Charleston, South Carolina, was associated with widespread liquefaction of shallow sand structures and their extravasation to the surface. Several seismically induced paleoliquefaction structures preserved within the shallow sediments in the meizoseismal area of the 1886 event were identified. Field evidence and radiocarbon dates suggest that at least two earthquakes of magnitudes greater than 6.2 preceded the 1886 event in the past 3000 to 3700 years. The evidence yielded an initial estimate of about 1500 to 1800 years for the maximum recurrence of destructive, intraplate earthquakes in the Charleston region.

  10. Variations in rupture process with recurrence interval in a repeated small earthquake

    USGS Publications Warehouse

    Vidale, J.E.; Ellsworth, W.L.; Cole, A.; Marone, Chris

    1994-01-01

    In theory and in laboratory experiments, friction on sliding surfaces such as rock, glass and metal increases with time since the previous episode of slip. This time dependence is a central pillar of the friction laws widely used to model earthquake phenomena. On natural faults, other properties, such as rupture velocity, porosity and fluid pressure, may also vary with the recurrence interval. Eighteen repetitions of the same small earthquake, separated by intervals ranging from a few days to several years, allow us to test these laboratory predictions in situ. The events with the longest time since the previous earthquake tend to have about 15% larger seismic moment than those with the shortest intervals, although this trend is weak. In addition, the rupture durations of the events with the longest recurrence intervals are more than a factor of two shorter than for the events with the shortest intervals. Both decreased duration and increased friction are consistent with progressive fault healing during the time of stationary contact.In theory and in laboratory experiments, friction on sliding surfaces such as rock, glass and metal increases with time since the previous episode of slip. This time dependence is a central pillar of the friction laws widely used to model earthquake phenomena. On natural faults, other properties, such as rupture velocity, porosity and fluid pressure, may also vary with the recurrence interval. Eighteen repetitions of the same small earthquake, separated by intervals ranging from a few days to several years, allow us to test these laboratory predictions in situ. The events with the longest time since the previous earthquake tend to have about 15% larger seismic moment than those with the shortest intervals, although this trend is weak. In addition, the rupture durations of the events with the longest recurrence intervals are more than a factor of two shorter than for the events with the shortest intervals. Both decreased duration and

  11. Recurrent slow slip event likely hastened by the 2011 Tohoku earthquake

    PubMed Central

    Hirose, Hitoshi; Kimura, Hisanori; Enescu, Bogdan; Aoi, Shin

    2012-01-01

    Slow slip events (SSEs) are another mode of fault deformation than the fast faulting of regular earthquakes. Such transient episodes have been observed at plate boundaries in a number of subduction zones around the globe. The SSEs near the Boso Peninsula, central Japan, are among the most documented SSEs, with the longest repeating history, of almost 30 y, and have a recurrence interval of 5 to 7 y. A remarkable characteristic of the slow slip episodes is the accompanying earthquake swarm activity. Our stable, long-term seismic observations enable us to detect SSEs using the recorded earthquake catalog, by considering an earthquake swarm as a proxy for a slow slip episode. Six recurrent episodes are identified in this way since 1982. The average duration of the SSE interoccurrence interval is 68 mo; however, there are significant fluctuations from this mean. While a regular cycle can be explained using a simple physical model, the mechanisms that are responsible for the observed fluctuations are poorly known. Here we show that the latest SSE in the Boso Peninsula was likely hastened by the stress transfer from the March 11, 2011 great Tohoku earthquake. Moreover, a similar mechanism accounts for the delay of an SSE in 1990 by a nearby earthquake. The low stress buildups and drops during the SSE cycle can explain the strong sensitivity of these SSEs to stress transfer from external sources. PMID:22949688

  12. Unusual geologic evidence of coeval seismic shaking and tsunamis shows variability in earthquake size and recurrence in the area of the giant 1960 Chile earthquake

    USGS Publications Warehouse

    Cisternas, M.; Garrett, E; Wesson, Robert L.; Dura, T.; Ely, L. L

    2017-01-01

    An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca-South American plate boundary. A 500-m long coastal outcrop on Isla Chiloé, midway along the 1960 rupture, provides continuous exposure of soil horizons buried locally by debris-flow diamicts and extensively by tsunami sand sheets. The diamicts flattened plants that yield geologically precise ages to correlate with well-dated evidence elsewhere. The 1960 event was preceded by three earthquakes that probably resembled it in their effects, in AD 898 - 1128, 1300 - 1398 and 1575, and by five relatively smaller intervening earthquakes. Earthquakes and tsunamis recurred exceptionally often between AD 1300 and 1575. Their average recurrence interval of 85 years only slightly exceeds the time already elapsed since 1960. This inference is of serious concern because no earthquake has been anticipated in the region so soon after the 1960 event, and current plate locking suggests that some segments of the boundary are already capable of producing large earthquakes. This long-term earthquake and tsunami history of one of the world's most seismically active subduction zones provides an example of variable rupture mode, in which earthquake size and recurrence interval vary from one earthquake to the next.

  13. Self-organized criticality in complex systems: Applicability to the interoccurrent and recurrent statistical behavior of earthquakes

    NASA Astrophysics Data System (ADS)

    Abaimov, Sergey G.

    The concept of self-organized criticality is associated with scale-invariant, fractal behavior; this concept is also applicable to earthquake systems. It is known that the interoccurrent frequency-size distribution of earthquakes in a region is scale-invariant and obeys the Gutenberg-Richter power-law dependence. Also, the interoccurrent time-interval distribution is known to obey Poissonian statistics excluding aftershocks. However, to estimate the hazard risk for a region it is necessary to know also the recurrent behavior of earthquakes at a given point on a fault. This behavior has been investigated in the literature, however, major questions remain unresolved. The reason is the small number of earthquakes in observed sequences. To overcome this difficulty this research utilizes numerical simulations of a slider-block model and a sand-pile model. Also, experimental observations of creep events on the creeping section of the San Andreas fault are processed and sequences up to 100 events are studied. Then the recurrent behavior of earthquakes at a given point on a fault or at a given fault is investigated. It is shown that both the recurrent frequency-size and the time-interval behaviors of earthquakes obey the Weibull distribution.

  14. Irregular earthquake recurrence patterns and slip variability on a plate-boundary Fault

    NASA Astrophysics Data System (ADS)

    Wechsler, N.; Rockwell, T. K.; Klinger, Y.

    2015-12-01

    The Dead Sea fault in the Levant represents a simple, segmented plate boundary from the Gulf of Aqaba northward to the Sea of Galilee, where it changes its character into a complex plate boundary with multiple sub-parallel faults in northern Israel, Lebanon and Syria. The studied Jordan Gorge (JG) segment is the northernmost part of the simple section, before the fault becomes more complex. Seven fault-crossing buried paleo-channels, offset by the Dead Sea fault, were investigated using paleoseismic and geophysical methods. The mapped offsets capture the long-term rupture history and slip-rate behavior on the JG fault segment for the past 4000 years. The ~20 km long JG segment appears to be more active (in term of number of earthquakes) than its neighboring segments to the south and north. The rate of movement on this segment varies considerably over the studied period: the long-term slip-rate for the entire 4000 years is similar to previously observed rates (~4 mm/yr), yet over shorter time periods the rate varies from 3-8 mm/yr. Paleoseismic data on both timing and displacement indicate a high COV >1 (clustered) with displacement per event varying by nearly an order of magnitude. The rate of earthquake production does not produce a time predictable pattern over a period of 2 kyr. We postulate that the seismic behavior of the JG fault is influenced by stress interactions with its neighboring faults to the north and south. Coulomb stress modelling demonstrates that an earthquake on any neighboring fault will increase the Coulomb stress on the JG fault and thus promote rupture. We conclude that deriving on-fault slip-rates and earthquake recurrence patterns from a single site and/or over a short time period can produce misleading results. The definition of an adequately long time period to resolve slip-rate is a question that needs to be addressed and requires further work.

  15. Earthquake recurrence and risk assessment in circum-Pacific seismic gaps

    USGS Publications Warehouse

    Thatcher, W.

    1989-01-01

    THE development of the concept of seismic gaps, regions of low earthquake activity where large events are expected, has been one of the notable achievements of seismology and plate tectonics. Its application to long-term earthquake hazard assessment continues to be an active field of seismological research. Here I have surveyed well documented case histories of repeated rupture of the same segment of circum-Pacific plate boundary and characterized their general features. I find that variability in fault slip and spatial extent of great earthquakes rupturing the same plate boundary segment is typical rather than exceptional but sequences of major events fill identified seismic gaps with remarkable order. Earthquakes are concentrated late in the seismic cycle and occur with increasing size and magnitude. Furthermore, earthquake rup-ture starts near zones of concentrated moment release, suggesting that high-slip regions control the timing of recurrent events. The absence of major earthquakes early in the seismic cycle indicates a more complex behaviour for lower-slip regions, which may explain the observed cycle-to-cycle diversity of gap-filling sequences. ?? 1989 Nature Publishing Group.

  16. Maximum earthquake magnitudes in the Aegean area constrained by tectonic moment release rates

    NASA Astrophysics Data System (ADS)

    Ch. Koravos, G.; Main, I. G.; Tsapanos, T. M.; Musson, R. M. W.

    2003-01-01

    Seismic moment release is usually dominated by the largest but rarest events, making the estimation of seismic hazard inherently uncertain. This uncertainty can be reduced by combining long-term tectonic deformation rates with short-term recurrence rates. Here we adopt this strategy to estimate recurrence rates and maximum magnitudes for tectonic zones in the Aegean area. We first form a merged catalogue for historical and instrumentally recorded earthquakes in the Aegean, based on a recently published catalogue for Greece and surrounding areas covering the time period 550BC-2000AD, at varying degrees of completeness. The historical data are recalibrated to allow for changes in damping in seismic instruments around 1911. We divide the area up into zones that correspond to recent determinations of deformation rate from satellite data. In all zones we find that the Gutenberg-Richter (GR) law holds at low magnitudes. We use Akaike's information criterion to determine the best-fitting distribution at high magnitudes, and classify the resulting frequency-magnitude distributions of the zones as critical (GR law), subcritical (gamma density distribution) or supercritical (`characteristic' earthquake model) where appropriate. We determine the ratio η of seismic to tectonic moment release rate. Low values of η (<0.5) corresponding to relatively aseismic deformation, are associated with higher b values (>1.0). The seismic and tectonic moment release rates are then combined to constrain recurrence rates and maximum credible magnitudes (in the range 6.7-7.6 mW where the results are well constrained) based on extrapolating the short-term seismic data. With current earthquake data, many of the tectonic zones show a characteristic distribution that leads to an elevated probability of magnitudes around 7, but a reduced probability of larger magnitudes above this value when compared with the GR trend. A modification of the generalized gamma distribution is suggested to account

  17. Earthquake recurrence models and occurrence probabilities of strong earthquakes in the North Aegean Trough (Greece)

    NASA Astrophysics Data System (ADS)

    Christos, Kourouklas; Eleftheria, Papadimitriou; George, Tsaklidis; Vassilios, Karakostas

    2018-06-01

    The determination of strong earthquakes' recurrence time above a predefined magnitude, associated with specific fault segments, is an important component of seismic hazard assessment. The occurrence of these earthquakes is neither periodic nor completely random but often clustered in time. This fact in connection with their limited number, due to shortage of the available catalogs, inhibits a deterministic approach for recurrence time calculation, and for this reason, application of stochastic processes is required. In this study, recurrence time determination in the area of North Aegean Trough (NAT) is developed by the application of time-dependent stochastic models, introducing an elastic rebound motivated concept for individual fault segments located in the study area. For this purpose, all the available information on strong earthquakes (historical and instrumental) with M w ≥ 6.5 is compiled and examined for magnitude completeness. Two possible starting dates of the catalog are assumed with the same magnitude threshold, M w ≥ 6.5 and divided into five data sets, according to a new segmentation model for the study area. Three Brownian Passage Time (BPT) models with different levels of aperiodicity are applied and evaluated with the Anderson-Darling test for each segment in both catalog data where possible. The preferable models are then used in order to estimate the occurrence probabilities of M w ≥ 6.5 shocks on each segment of NAT for the next 10, 20, and 30 years since 01/01/2016. Uncertainties in probability calculations are also estimated using a Monte Carlo procedure. It must be mentioned that the provided results should be treated carefully because of their dependence to the initial assumptions. Such assumptions exhibit large variability and alternative means of these may return different final results.

  18. Long-Term Fault Memory: A New Time-Dependent Recurrence Model for Large Earthquake Clusters on Plate Boundaries

    NASA Astrophysics Data System (ADS)

    Salditch, L.; Brooks, E. M.; Stein, S.; Spencer, B. D.; Campbell, M. R.

    2017-12-01

    A challenge for earthquake hazard assessment is that geologic records often show large earthquakes occurring in temporal clusters separated by periods of quiescence. For example, in Cascadia, a paleoseismic record going back 10,000 years shows four to five clusters separated by approximately 1,000 year gaps. If we are still in the cluster that began 1700 years ago, a large earthquake is likely to happen soon. If the cluster has ended, a great earthquake is less likely. For a Gaussian distribution of recurrence times, the probability of an earthquake in the next 50 years is six times larger if we are still in the most recent cluster. Earthquake hazard assessments typically employ one of two recurrence models, neither of which directly incorporate clustering. In one, earthquake probability is time-independent and modeled as Poissonian, so an earthquake is equally likely at any time. The fault has no "memory" because when a prior earthquake occurred has no bearing on when the next will occur. The other common model is a time-dependent earthquake cycle in which the probability of an earthquake increases with time until one happens, after which the probability resets to zero. Because the probability is reset after each earthquake, the fault "remembers" only the last earthquake. This approach can be used with any assumed probability density function for recurrence times. We propose an alternative, Long-Term Fault Memory (LTFM), a modified earthquake cycle model where the probability of an earthquake increases with time until one happens, after which it decreases, but not necessarily to zero. Hence the probability of the next earthquake depends on the fault's history over multiple cycles, giving "long-term memory". Physically, this reflects an earthquake releasing only part of the elastic strain stored on the fault. We use the LTFM to simulate earthquake clustering along the San Andreas Fault and Cascadia. In some portions of the simulated earthquake history, events would

  19. Earthquake Recurrence along the Kuril Trench: A New View from Paleoseismology

    NASA Astrophysics Data System (ADS)

    Satake, K.; Nanayama, F.

    2003-12-01

    Paleoseismological data along the Pacific coast of eastern Hokkaido indicate that unusual earthquakes have repeated at about 500 year interval with the most recent event in the 17th century. Along the Kuril trench, interplate earthquakes with rupture length of 100-200 km occurred in 1952 (Mw 8.1) and 1973 (Mw 7.8), as well as 1843 (M 8.0) and 1894 (M 7.9), which have been considered characteristics of this subduction zone. We review paleoseismological data, examine coastal deformation and tsunami inundation from fault models, and propose a model of earthquake recurrence in the Kuril subduction zone. Pleistocene marine terraces on the Pacific coast show slight net uplift, at an average of 0.1-0.4 mm/yr in the past several hundred thousand years, whereas tide-gauge data show gradual subsidence of 8-9 mm/yr since 1900. Infrequent unusual event (Armageddon) has been inferred (Ikeda, 1996) to resolve this conflict. Holocene stratigraphic and microfossil studies have indicated sea-level changes in the last 3 ka (e.g., Sawai, 2001). Each event is marked by an abrupt upward change from brackish bay deposits to freshwater peat. The youngest change has been dated in the 17th century with an estimated uplift amount of 0.5-1m (Atwater et al., 2003). Such evidence has been found along the 100 km long coast and recurred up to seven times in the last 2.5 ka (Kelsey et al., 2002). Extensive tsunami deposits indicate large prehistoric tsunamis (Nanayama et al., 2003). At Kiritappu, for instance, sand sheets extend 3 km inland, much further than historic tsunamis. Ten sheets of tsunami deposits indicate recurrence of such unusual tsunami with an average recurrence interval of about 500 years. The most recent event occurred in the 17th century. Historic documents in Honshu rules out unusual tsunamis that would cause damage along the Sanriku coast. Tsunami damage from the 1611 and 1677 earthquakes, both along the Japan trench, have been documented along the Sanriku coast. We modeled

  20. A New Insight into the Earthquake Recurrence Studies from the Three-parameter Generalized Exponential Distributions

    NASA Astrophysics Data System (ADS)

    Pasari, S.; Kundu, D.; Dikshit, O.

    2012-12-01

    Earthquake recurrence interval is one of the important ingredients towards probabilistic seismic hazard assessment (PSHA) for any location. Exponential, gamma, Weibull and lognormal distributions are quite established probability models in this recurrence interval estimation. However, they have certain shortcomings too. Thus, it is imperative to search for some alternative sophisticated distributions. In this paper, we introduce a three-parameter (location, scale and shape) exponentiated exponential distribution and investigate the scope of this distribution as an alternative of the afore-mentioned distributions in earthquake recurrence studies. This distribution is a particular member of the exponentiated Weibull distribution. Despite of its complicated form, it is widely accepted in medical and biological applications. Furthermore, it shares many physical properties with gamma and Weibull family. Unlike gamma distribution, the hazard function of generalized exponential distribution can be easily computed even if the shape parameter is not an integer. To contemplate the plausibility of this model, a complete and homogeneous earthquake catalogue of 20 events (M ≥ 7.0) spanning for the period 1846 to 1995 from North-East Himalayan region (20-32 deg N and 87-100 deg E) has been used. The model parameters are estimated using maximum likelihood estimator (MLE) and method of moment estimator (MOME). No geological or geophysical evidences have been considered in this calculation. The estimated conditional probability reaches quite high after about a decade for an elapsed time of 17 years (i.e. 2012). Moreover, this study shows that the generalized exponential distribution fits the above data events more closely compared to the conventional models and hence it is tentatively concluded that generalized exponential distribution can be effectively considered in earthquake recurrence studies.

  1. Development of Final A-Fault Rupture Models for WGCEP/ NSHMP Earthquake Rate Model 2

    USGS Publications Warehouse

    Field, Edward H.; Weldon, Ray J.; Parsons, Thomas; Wills, Chris J.; Dawson, Timothy E.; Stein, Ross S.; Petersen, Mark D.

    2008-01-01

    This appendix discusses how we compute the magnitude and rate of earthquake ruptures for the seven Type-A faults (Elsinore, Garlock, San Jacinto, S. San Andreas, N. San Andreas, Hayward-Rodgers Creek, and Calaveras) in the WGCEP/NSHMP Earthquake Rate Model 2 (referred to as ERM 2. hereafter). By definition, Type-A faults are those that have relatively abundant paleoseismic information (e.g., mean recurrence-interval estimates). The first section below discusses segmentation-based models, where ruptures are assumed be confined to one or more identifiable segments. The second section discusses an un-segmented-model option, the third section discusses results and implications, and we end with a discussion of possible future improvements. General background information can be found in the main report.

  2. Building Time-Dependent Earthquake Recurrence Models for Probabilistic Loss Computations

    NASA Astrophysics Data System (ADS)

    Fitzenz, D. D.; Nyst, M.

    2013-12-01

    We present a Risk Management perspective on earthquake recurrence on mature faults, and the ways that it can be modeled. The specificities of Risk Management relative to Probabilistic Seismic Hazard Assessment (PSHA), include the non-linearity of the exceedance probability curve for losses relative to the frequency of event occurrence, the fact that losses at all return periods are needed (and not at discrete values of the return period), and the set-up of financial models which sometimes require the modeling of realizations of the order in which events may occur (I.e., simulated event dates are important, whereas only average rates of occurrence are routinely used in PSHA). We use New Zealand as a case study and review the physical characteristics of several faulting environments, contrasting them against properties of three probability density functions (PDFs) widely used to characterize the inter-event time distributions in time-dependent recurrence models. We review the data available to help constrain both the priors and the recurrence process. And we propose that with the current level of knowledge, the best way to quantify the recurrence of large events on mature faults is to use a Bayesian combination of models, i.e., the decomposition of the inter-event time distribution into a linear combination of individual PDFs with their weight given by the posterior distribution. Finally we propose to the community : 1. A general debate on how best to incorporate our knowledge (e.g., from geology, geomorphology) on plausible models and model parameters, but also preserve the information on what we do not know; and 2. The creation and maintenance of a global database of priors, data, and model evidence, classified by tectonic region, special fluid characteristic (pH, compressibility, pressure), fault geometry, and other relevant properties so that we can monitor whether some trends emerge in terms of which model dominates in which conditions.

  3. Geodetic slip rate for the eastern California shear zone and the recurrence time of Mojave desert earthquakes

    USGS Publications Warehouse

    Sauber, J.; Thatcher, W.; Solomon, S.C.; Lisowski, M.

    1994-01-01

    Where the San Andreas fault passes along the southwestern margin of the Mojave desert, it exhibits a large change in trend, and the deformation associated with the Pacific/North American plate boundary is distributed broadly over a complex shear zone. The importance of understanding the partitioning of strain across this region, especially to the east of the Mojave segment of the San Andreas in a region known as the eastern California shear zone (ECSZ), was highlighted by the occurrence (on 28 June 1992) of the magnitude 7.3 Landers earthquake in this zone. Here we use geodetic observations in the central Mojave desert to obtain new estimates for the rate and distribution of strain across a segment of the ECSZ, and to determine a coseismic strain drop of ~770 ??rad for the Landers earthquake. From these results we infer a strain energy recharge time of 3,500-5,000 yr for a Landers-type earthquake and a slip rate of ~12 mm yr-1 across the faults of the central Mojave. The latter estimate implies that a greater fraction of plate motion than heretofore inferred from geodetic data is accommodated across the ECSZ.

  4. Quasi-periodic recurrence of great and giant earthquakes in South-Central Chile inferred from lacustrine turbidite records

    NASA Astrophysics Data System (ADS)

    Strasser, M.; Moernaut, J.; Van Daele, M. E.; De Batist, M. A. O.

    2017-12-01

    Coastal paleoseismic records in south-central Chile indicate that giant megathrust earthquakes -such as in AD1960 (Mw9.5)- occur on average every 300 yrs. Based on geodetic data, it was postulated that the area already has the potential for a Mw8 earthquake. However, to estimate the probability for such a great earthquake from a paleo-perspective, one needs to reconstruct the long-term recurrence pattern of megathrust earthquakes. Here, we present two long lacustrine records, comprising up to 35 earthquake-triggered turbidites over the last 4800 yrs. Calibration of turbidite extent with historical earthquake intensity reveals a different macroseismic intensity threshold (≥VII½ vs. ≥VI½) for the generation of turbidites at the coring sites. The strongest earthquakes (≥VII½) have longer recurrence intervals (292 ±93 yrs) than earthquakes with intensity of ≥VI½ (139 ±69 yrs). The coefficient of variation (CoV) of inter-event times indicate that the strongest earthquakes recur in a quasi-periodic way (CoV: 0.32) and follow a normal distribution. Including also "smaller" earthquakes (Intensity down to VI½) increases the CoV (0.5) and fits best with a Weibull distribution. Regional correlation of our multi-threshold shaking records with coastal records of tsunami and coseismic subsidence suggests that the intensity ≥VII½ events repeatedly ruptured the same part of the megathrust over a distance of at least 300 km and can be assigned to a Mw ≥ 8.6. We hypothesize that a zone of high plate locking -identified by GPS data and large slip in AD 1960- acts as a dominant regional asperity, on which elastic strain builds up over several centuries and mostly gets released in quasi-periodic great and giant earthquakes. For the next 110 yrs, we infer an enhanced probability for a Mw 7.7-8.5 earthquake whereas the probability for a Mw ≥ 8.6 (AD1960-like) earthquake remains low.

  5. Detection of Temporally and Spatially Limited Periodic Earthquake Recurrence in Synthetic Seismic Records

    NASA Astrophysics Data System (ADS)

    Zielke, O.; Arrowsmith, R. J.

    2005-12-01

    The nonlinear dynamics of fault behavior are dominated by complex interactions among the multiple processes controlling the system. For example, temporal and spatial variations in pore pressure, healing effects, and stress transfer cause significant heterogeneities in fault properties and the stress-field at the sub-fault level. Numerical and laboratory fault models show that the interaction of large systems of fault elements causes the entire system to develop into a state of self-organized criticality. Once in this state, small perturbations of the system may result in chain reactions (i.e., earthquakes) which can affect any number of fault segments. This sensitivity to small perturbations is strong evidence for chaotic fault behavior, which implies that exact event prediction is not possible. However, earthquake prediction with a useful accuracy is nevertheless possible. Studies of other natural chaotic systems have shown that they may enter states of metastability, in which the system's behavior is predictable. Applying this concept to earthquake faults, these windows of metastable behavior should be characterized by periodic earthquake recurrence. The observed periodicity of the Parkfield, CA (M= 6) events may resemble such a window of metastability. I am statistically analyzing numerically generated seismic records to study these phases of periodic behavior. In this preliminary study, seismic records were generated using a model introduced by Nakanishi [Phys. Rev. A, 43, 6613-6621, 1991]. It consists of a one-dimensional chain of blocks (interconnected by springs) with a relaxation function that mimics velocity-weakened frictional behavior. The earthquakes occurring in this model show generally a power-law frequency-size distribution. However, for large events the distribution has a shoulder where the frequency of events is higher than expected from the power law. I have analyzed time-series of single block motions within the system. These time-series include

  6. Discrepancy between earthquake rates implied by historic earthquakes and a consensus geologic source model for California

    USGS Publications Warehouse

    Petersen, M.D.; Cramer, C.H.; Reichle, M.S.; Frankel, A.D.; Hanks, T.C.

    2000-01-01

    We examine the difference between expected earthquake rates inferred from the historical earthquake catalog and the geologic data that was used to develop the consensus seismic source characterization for the state of California [California Department of Conservation, Division of Mines and Geology (CDMG) and U.S. Geological Survey (USGS) Petersen et al., 1996; Frankel et al., 1996]. On average the historic earthquake catalog and the seismic source model both indicate about one M 6 or greater earthquake per year in the state of California. However, the overall earthquake rates of earthquakes with magnitudes (M) between 6 and 7 in this seismic source model are higher, by at least a factor of 2, than the mean historic earthquake rates for both southern and northern California. The earthquake rate discrepancy results from a seismic source model that includes earthquakes with characteristic (maximum) magnitudes that are primarily between M 6.4 and 7.1. Many of these faults are interpreted to accommodate high strain rates from geologic and geodetic data but have not ruptured in large earthquakes during historic time. Our sensitivity study indicates that the rate differences between magnitudes 6 and 7 can be reduced by adjusting the magnitude-frequency distribution of the source model to reflect more characteristic behavior, by decreasing the moment rate available for seismogenic slip along faults, by increasing the maximum magnitude of the earthquake on a fault, or by decreasing the maximum magnitude of the background seismicity. However, no single parameter can be adjusted, consistent with scientific consensus, to eliminate the earthquake rate discrepancy. Applying a combination of these parametric adjustments yields an alternative earthquake source model that is more compatible with the historic data. The 475-year return period hazard for peak ground and 1-sec spectral acceleration resulting from this alternative source model differs from the hazard resulting from the

  7. Spatial Distribution of the Coefficient of Variation for the Paleo-Earthquakes in Japan

    NASA Astrophysics Data System (ADS)

    Nomura, S.; Ogata, Y.

    2015-12-01

    Renewal processes, point prccesses in which intervals between consecutive events are independently and identically distributed, are frequently used to describe this repeating earthquake mechanism and forecast the next earthquakes. However, one of the difficulties in applying recurrent earthquake models is the scarcity of the historical data. Most studied fault segments have few, or only one observed earthquake that often have poorly constrained historic and/or radiocarbon ages. The maximum likelihood estimate from such a small data set can have a large bias and error, which tends to yield high probability for the next event in a very short time span when the recurrence intervals have similar lengths. On the other hand, recurrence intervals at a fault depend on the long-term slip rate caused by the tectonic motion in average. In addition, recurrence times are also fluctuated by nearby earthquakes or fault activities which encourage or discourage surrounding seismicity. These factors have spatial trends due to the heterogeneity of tectonic motion and seismicity. Thus, this paper introduces a spatial structure on the key parameters of renewal processes for recurrent earthquakes and estimates it by using spatial statistics. Spatial variation of mean and variance parameters of recurrence times are estimated in Bayesian framework and the next earthquakes are forecasted by Bayesian predictive distributions. The proposal model is applied for recurrent earthquake catalog in Japan and its result is compared with the current forecast adopted by the Earthquake Research Committee of Japan.

  8. Recurrence of great earthquakes and tsunamis, Aceh Province, Sumatra

    NASA Astrophysics Data System (ADS)

    Rubin, C. M.; Horton, B.; Sieh, K.; Pilarczyk, J.; Hawkes, A. D.; Daly, P.; Kelsey, H. M.; McKinnon, E.; Ismail, N.; Daryono, M. R.

    2013-12-01

    The timing and characterization of ancient earthquakes and tsunamis inferred from a variety of geologic studies in Aceh Province, Sumatra, are helping to understand predecessors of the 2004 event in the Indian Ocean region. We report results from three different depositional environments along the western and northern coast of Aceh Province, Sumatra, that illuminate the history of tsunamis through the past several millennia. Within a coastal cave along the western coast is an extraordinary sedimentary deposit that contains a 7,000-year long sequence of tsunami sands separated by bat guano. In two sea cliff exposures along the northern coast of Aceh is evidence for two closely timed predecessors of the giant 2004 tsunami that destroyed communities along the coast about 500 years ago. In addition, coastal wetlands along the western coast document land-level changes and tsunamis associated with the earthquake cycle in the early- to mid-Holocene. Together these records show a marked variability in recurrence of large tsunamis along the Acehnese coast. Time between inundations averages close to 500 years but range from a few centuries to a millennium.

  9. Slip rate and slip magnitudes of past earthquakes along the Bogd left-lateral strike-slip fault (Mongolia)

    USGS Publications Warehouse

    Rizza, M.; Ritz, J.-F.; Braucher, R.; Vassallo, R.; Prentice, C.; Mahan, S.; McGill, S.; Chauvet, A.; Marco, S.; Todbileg, M.; Demberel, S.; Bourles, D.

    2011-01-01

    We carried out morphotectonic studies along the left-lateral strike-slip Bogd Fault, the principal structure involved in the Gobi-Altay earthquake of 1957 December 4 (published magnitudes range from 7.8 to 8.3). The Bogd Fault is 260 km long and can be subdivided into five main geometric segments, based on variation in strike direction. West to East these segments are, respectively: the West Ih Bogd (WIB), The North Ih Bogd (NIB), the West Ih Bogd (WIB), the West Baga Bogd (WBB) and the East Baga Bogd (EBB) segments. Morphological analysis of offset streams, ridges and alluvial fans-particularly well preserved in the arid environment of the Gobi region-allows evaluation of late Quaternary slip rates along the different faults segments. In this paper, we measure slip rates over the past 200 ka at four sites distributed across the three western segments of the Bogd Fault. Our results show that the left-lateral slip rate is ~1 mm yr-1 along the WIB and EIB segments and ~0.5 mm yr-1 along the NIB segment. These variations are consistent with the restraining bend geometry of the Bogd Fault. Our study also provides additional estimates of the horizontal offset associated with the 1957 earthquake along the western part of the Bogd rupture, complementing previously published studies. We show that the mean horizontal offset associated with the 1957 earthquake decreases progressively from 5.2 m in the west to 2.0 m in the east, reflecting the progressive change of kinematic style from pure left-lateral strike-slip faulting to left-lateral-reverse faulting. Along the three western segments, we measure cumulative displacements that are multiples of the 1957 coseismic offset, which may be consistent with a characteristic slip. Moreover, using these data, we re-estimate the moment magnitude of the Gobi-Altay earthquake at Mw 7.78-7.95. Combining our slip rate estimates and the slip distribution per event we also determined a mean recurrence interval of ~2500-5200 yr for past

  10. The Impact of Frictional Healing on Stick-Slip Recurrence Interval and Stress Drop: Implications for Earthquake Scaling

    NASA Astrophysics Data System (ADS)

    Im, Kyungjae; Elsworth, Derek; Marone, Chris; Leeman, John

    2017-12-01

    Interseismic frictional healing is an essential process in the seismic cycle. Observations of both natural and laboratory earthquakes demonstrate that the magnitude of stress drop scales with the logarithm of recurrence time, which is a cornerstone of the rate and state friction (RSF) laws. However, the origin of this log linear behavior and short time "cutoff" for small recurrence intervals remains poorly understood. Here we use RSF laws to demonstrate that the back-projected time of null-healing intrinsically scales with the initial frictional state θi. We explore this behavior and its implications for (1) the short-term cutoff time of frictional healing and (2) the connection between healing rates derived from stick-slip sliding versus slide-hold-slide tests. We use a novel, continuous solution of RSF for a one-dimensional spring-slider system with inertia. The numerical solution continuously traces frictional state evolution (and healing) and shows that stick-slip cutoff time also scales with frictional state at the conclusion of the dynamic slip process θi (=Dc/Vpeak). This numerical investigation on the origins of stick-slip response is verified by comparing laboratory data for a range of peak slip velocities. Slower slip motions yield lesser magnitude of friction drop at a given time due to higher frictional state at the end of each slip event. Our results provide insight on the origin of log linear stick-slip evolution and suggest an approach to estimating the critical slip distance on faults that exhibit gradual accelerations, such as for slow earthquakes.

  11. Short-term volcano-tectonic earthquake forecasts based on a moving mean recurrence time algorithm: the El Hierro seismo-volcanic crisis experience

    NASA Astrophysics Data System (ADS)

    García, Alicia; De la Cruz-Reyna, Servando; Marrero, José M.; Ortiz, Ramón

    2016-05-01

    Under certain conditions, volcano-tectonic (VT) earthquakes may pose significant hazards to people living in or near active volcanic regions, especially on volcanic islands; however, hazard arising from VT activity caused by localized volcanic sources is rarely addressed in the literature. The evolution of VT earthquakes resulting from a magmatic intrusion shows some orderly behaviour that may allow the occurrence and magnitude of major events to be forecast. Thus governmental decision makers can be supplied with warnings of the increased probability of larger-magnitude earthquakes on the short-term timescale. We present here a methodology for forecasting the occurrence of large-magnitude VT events during volcanic crises; it is based on a mean recurrence time (MRT) algorithm that translates the Gutenberg-Richter distribution parameter fluctuations into time windows of increased probability of a major VT earthquake. The MRT forecasting algorithm was developed after observing a repetitive pattern in the seismic swarm episodes occurring between July and November 2011 at El Hierro (Canary Islands). From then on, this methodology has been applied to the consecutive seismic crises registered at El Hierro, achieving a high success rate in the real-time forecasting, within 10-day time windows, of volcano-tectonic earthquakes.

  12. Slip rate and slip magnitudes of past earthquakes along the Bogd left-lateral strike-slip fault (Mongolia)

    USGS Publications Warehouse

    Prentice, Carol S.; Rizza, M.; Ritz, J.F.; Baucher, R.; Vassallo, R.; Mahan, S.

    2011-01-01

    We carried out morphotectonic studies along the left-lateral strike-slip Bogd Fault, the principal structure involved in the Gobi-Altay earthquake of 1957 December 4 (published magnitudes range from 7.8 to 8.3). The Bogd Fault is 260 km long and can be subdivided into five main geometric segments, based on variation in strike direction. West to East these segments are, respectively: the West Ih Bogd (WIB), The North Ih Bogd (NIB), the West Ih Bogd (WIB), the West Baga Bogd (WBB) and the East Baga Bogd (EBB) segments. Morphological analysis of offset streams, ridges and alluvial fans—particularly well preserved in the arid environment of the Gobi region—allows evaluation of late Quaternary slip rates along the different faults segments. In this paper, we measure slip rates over the past 200 ka at four sites distributed across the three western segments of the Bogd Fault. Our results show that the left-lateral slip rate is∼1 mm yr–1 along the WIB and EIB segments and∼0.5 mm yr–1 along the NIB segment. These variations are consistent with the restraining bend geometry of the Bogd Fault. Our study also provides additional estimates of the horizontal offset associated with the 1957 earthquake along the western part of the Bogd rupture, complementing previously published studies. We show that the mean horizontal offset associated with the 1957 earthquake decreases progressively from 5.2 m in the west to 2.0 m in the east, reflecting the progressive change of kinematic style from pure left-lateral strike-slip faulting to left-lateral-reverse faulting. Along the three western segments, we measure cumulative displacements that are multiples of the 1957 coseismic offset, which may be consistent with a characteristic slip. Moreover, using these data, we re-estimate the moment magnitude of the Gobi-Altay earthquake at Mw 7.78–7.95. Combining our slip rate estimates and the slip distribution per event we also determined a mean recurrence interval of∼2500

  13. Monte Carlo Method for Determining Earthquake Recurrence Parameters from Short Paleoseismic Catalogs: Example Calculations for California

    USGS Publications Warehouse

    Parsons, Tom

    2008-01-01

    Paleoearthquake observations often lack enough events at a given site to directly define a probability density function (PDF) for earthquake recurrence. Sites with fewer than 10-15 intervals do not provide enough information to reliably determine the shape of the PDF using standard maximum-likelihood techniques [e.g., Ellsworth et al., 1999]. In this paper I present a method that attempts to fit wide ranges of distribution parameters to short paleoseismic series. From repeated Monte Carlo draws, it becomes possible to quantitatively estimate most likely recurrence PDF parameters, and a ranked distribution of parameters is returned that can be used to assess uncertainties in hazard calculations. In tests on short synthetic earthquake series, the method gives results that cluster around the mean of the input distribution, whereas maximum likelihood methods return the sample means [e.g., NIST/SEMATECH, 2006]. For short series (fewer than 10 intervals), sample means tend to reflect the median of an asymmetric recurrence distribution, possibly leading to an overestimate of the hazard should they be used in probability calculations. Therefore a Monte Carlo approach may be useful for assessing recurrence from limited paleoearthquake records. Further, the degree of functional dependence among parameters like mean recurrence interval and coefficient of variation can be established. The method is described for use with time-independent and time-dependent PDF?s, and results from 19 paleoseismic sequences on strike-slip faults throughout the state of California are given.

  14. Monte Carlo method for determining earthquake recurrence parameters from short paleoseismic catalogs: Example calculations for California

    USGS Publications Warehouse

    Parsons, T.

    2008-01-01

    Paleoearthquake observations often lack enough events at a given site to directly define a probability density function (PDF) for earthquake recurrence. Sites with fewer than 10-15 intervals do not provide enough information to reliably determine the shape of the PDF using standard maximum-likelihood techniques (e.g., Ellsworth et al., 1999). In this paper I present a method that attempts to fit wide ranges of distribution parameters to short paleoseismic series. From repeated Monte Carlo draws, it becomes possible to quantitatively estimate most likely recurrence PDF parameters, and a ranked distribution of parameters is returned that can be used to assess uncertainties in hazard calculations. In tests on short synthetic earthquake series, the method gives results that cluster around the mean of the input distribution, whereas maximum likelihood methods return the sample means (e.g., NIST/SEMATECH, 2006). For short series (fewer than 10 intervals), sample means tend to reflect the median of an asymmetric recurrence distribution, possibly leading to an overestimate of the hazard should they be used in probability calculations. Therefore a Monte Carlo approach may be useful for assessing recurrence from limited paleoearthquake records. Further, the degree of functional dependence among parameters like mean recurrence interval and coefficient of variation can be established. The method is described for use with time-independent and time-dependent PDFs, and results from 19 paleoseismic sequences on strike-slip faults throughout the state of California are given.

  15. Long‐term creep rates on the Hayward Fault: evidence for controls on the size and frequency of large earthquakes

    USGS Publications Warehouse

    Lienkaemper, James J.; McFarland, Forrest S.; Simpson, Robert W.; Bilham, Roger; Ponce, David A.; Boatwright, John; Caskey, S. John

    2012-01-01

    The Hayward fault (HF) in California exhibits large (Mw 6.5–7.1) earthquakes with short recurrence times (161±65 yr), probably kept short by a 26%–78% aseismic release rate (including postseismic). Its interseismic release rate varies locally over time, as we infer from many decades of surface creep data. Earliest estimates of creep rate, primarily from infrequent surveys of offset cultural features, revealed distinct spatial variation in rates along the fault, but no detectable temporal variation. Since the 1989 Mw 6.9 Loma Prieta earthquake (LPE), monitoring on 32 alinement arrays and 5 creepmeters has greatly improved the spatial and temporal resolution of creep rate. We now identify significant temporal variations, mostly associated with local and regional earthquakes. The largest rate change was a 6‐yr cessation of creep along a 5‐km length near the south end of the HF, attributed to a regional stress drop from the LPE, ending in 1996 with a 2‐cm creep event. North of there near Union City starting in 1991, rates apparently increased by 25% above pre‐LPE levels on a 16‐km‐long reach of the fault. Near Oakland in 2007 an Mw 4.2 earthquake initiated a 1–2 cm creep event extending 10–15 km along the fault. Using new better‐constrained long‐term creep rates, we updated earlier estimates of depth to locking along the HF. The locking depths outline a single, ∼50‐km‐long locked or retarded patch with the potential for an Mw∼6.8 event equaling the 1868 HF earthquake. We propose that this inferred patch regulates the size and frequency of large earthquakes on HF.

  16. Is earthquake rate in south Iceland modified by seasonal loading?

    NASA Astrophysics Data System (ADS)

    Jonsson, S.; Aoki, Y.; Drouin, V.

    2017-12-01

    Several temporarily varying processes have the potential of modifying the rate of earthquakes in the south Iceland seismic zone, one of the two most active seismic zones in Iceland. These include solid earth tides, seasonal meteorological effects and influence from passing weather systems, and variations in snow and glacier loads. In this study we investigate the influence these processes may have on crustal stresses and stressing rates in the seismic zone and assess whether they appear to be influencing the earthquake rate. While historical earthquakes in the south Iceland have preferentially occurred in early summer, this tendency is less clear for small earthquakes. The local earthquake catalogue (going back to 1991, magnitude of completeness < 1.0) has indeed more earthquakes in summer than in winter. However, this pattern is strongly influenced by aftershock sequences of the largest M6+ earthquakes, which occurred in June 2000 and May 2008. Standard Reasenberg earthquake declustering or more involved model independent stochastic declustering algorithms are not capable of fully eliminating the aftershocks from the catalogue. We therefore inspected the catalogue for the time period before 2000 and it shows limited seasonal tendency in earthquake occurrence. Our preliminary results show no clear correlation between earthquake rates and short-term stressing variations induced from solid earth tides or passing storms. Seasonal meteorological effects also appear to be too small to influence the earthquake activity. Snow and glacier load variations induce significant vertical motions in the area with peak loading occurring in Spring (April-May) and maximum unloading in Fall (Sept.-Oct.). Early summer occurrence of historical earthquakes therefore correlates with early unloading rather than with the peak unloading or unloading rate, which appears to indicate limited influence of this seasonal process on the earthquake activity.

  17. Increased Earthquake Rates in the Central and Eastern US Portend Higher Earthquake Hazards

    NASA Astrophysics Data System (ADS)

    Llenos, A. L.; Rubinstein, J. L.; Ellsworth, W. L.; Mueller, C. S.; Michael, A. J.; McGarr, A.; Petersen, M. D.; Weingarten, M.; Holland, A. A.

    2014-12-01

    Since 2009 the central and eastern United States has experienced an unprecedented increase in the rate of M≥3 earthquakes that is unlikely to be due to natural variation. Where the rates have increased so has the seismic hazard, making it important to understand these changes. Areas with significant seismicity increases are limited to areas where oil and gas production take place. By far the largest contributor to the seismicity increase is Oklahoma, where recent studies suggest that these rate changes may be due to fluid injection (e.g., Keranen et al., Geology, 2013; Science, 2014). Moreover, the area of increased seismicity in northern Oklahoma that began in 2013 coincides with the Mississippi Lime play, where well completions greatly increased the year before the seismicity increase. This suggests a link to oil and gas production either directly or from the disposal of significant amounts of produced water within the play. For the purpose of assessing the hazard due to these earthquakes, should they be treated differently from natural earthquakes? Previous studies suggest that induced seismicity may differ from natural seismicity in clustering characteristics or frequency-magnitude distributions (e.g., Bachmann et al., GJI, 2011; Llenos and Michael, BSSA, 2013). These differences could affect time-independent hazard computations, which typically assume that clustering and size distribution remain constant. In Oklahoma, as well as other areas of suspected induced seismicity, we find that earthquakes since 2009 tend to be considerably more clustered in space and time than before 2009. However differences between various regional and national catalogs leave unclear whether there are significant changes in magnitude distribution. Whether they are due to natural or industrial causes, the increased earthquake rates in these areas could increase the hazard in ways that are not accounted for in current hazard assessment practice. Clearly the possibility of induced

  18. Models of recurrent strike-slip earthquake cycles and the state of crustal stress

    NASA Technical Reports Server (NTRS)

    Lyzenga, Gregory A.; Raefsky, Arthur; Mulligan, Stephanie G.

    1991-01-01

    Numerical models of the strike-slip earthquake cycle, assuming a viscoelastic asthenosphere coupling model, are examined. The time-dependent simulations incorporate a stress-driven fault, which leads to tectonic stress fields and earthquake recurrence histories that are mutually consistent. Single-fault simulations with constant far-field plate motion lead to a nearly periodic earthquake cycle and a distinctive spatial distribution of crustal shear stress. The predicted stress distribution includes a local minimum in stress at depths less than typical seismogenic depths. The width of this stress 'trough' depends on the magnitude of crustal stress relative to asthenospheric drag stresses. The models further predict a local near-fault stress maximum at greater depths, sustained by the cyclic transfer of strain from the elastic crust to the ductile asthenosphere. Models incorporating both low-stress and high-stress fault strength assumptions are examined, under Newtonian and non-Newtonian rheology assumptions. Model results suggest a preference for low-stress (a shear stress level of about 10 MPa) fault models, in agreement with previous estimates based on heat flow measurements and other stress indicators.

  19. The Mw 7.7 Bhuj earthquake: Global lessons for earthquake hazard in intra-plate regions

    USGS Publications Warehouse

    Schweig, E.; Gomberg, J.; Petersen, M.; Ellis, M.; Bodin, P.; Mayrose, L.; Rastogi, B.K.

    2003-01-01

    The Mw 7.7 Bhuj earthquake occurred in the Kachchh District of the State of Gujarat, India on 26 January 2001, and was one of the most damaging intraplate earthquakes ever recorded. This earthquake is in many ways similar to the three great New Madrid earthquakes that occurred in the central United States in 1811-1812, An Indo-US team is studying the similarities and differences of these sequences in order to learn lessons for earthquake hazard in intraplate regions. Herein we present some preliminary conclusions from that study. Both the Kutch and New Madrid regions have rift type geotectonic setting. In both regions the strain rates are of the order of 10-9/yr and attenuation of seismic waves as inferred from observations of intensity and liquefaction are low. These strain rates predict recurrence intervals for Bhuj or New Madrid sized earthquakes of several thousand years or more. In contrast, intervals estimated from paleoseismic studies and from other independent data are significantly shorter, probably hundreds of years. All these observations together may suggest that earthquakes relax high ambient stresses that are locally concentrated by rheologic heterogeneities, rather than loading by plate-tectonic forces. The latter model generally underlies basic assumptions made in earthquake hazard assessment, that the long-term average rate of energy released by earthquakes is determined by the tectonic loading rate, which thus implies an inherent average periodicity of earthquake occurrence. Interpreting the observations in terms of the former model therefore may require re-examining the basic assumptions of hazard assessment.

  20. Accounting for orphaned aftershocks in the earthquake background rate

    USGS Publications Warehouse

    Van Der Elst, Nicholas

    2017-01-01

    Aftershocks often occur within cascades of triggered seismicity in which each generation of aftershocks triggers an additional generation, and so on. The rate of earthquakes in any particular generation follows Omori's law, going approximately as 1/t. This function decays rapidly, but is heavy-tailed, and aftershock sequences may persist for long times at a rate that is difficult to discriminate from background. It is likely that some apparently spontaneous earthquakes in the observational catalogue are orphaned aftershocks of long-past main shocks. To assess the relative proportion of orphaned aftershocks in the apparent background rate, I develop an extension of the ETAS model that explicitly includes the expected contribution of orphaned aftershocks to the apparent background rate. Applying this model to California, I find that the apparent background rate can be almost entirely attributed to orphaned aftershocks, depending on the assumed duration of an aftershock sequence. This implies an earthquake cascade with a branching ratio (the average number of directly triggered aftershocks per main shock) of nearly unity. In physical terms, this implies that very few earthquakes are completely isolated from the perturbing effects of other earthquakes within the fault system. Accounting for orphaned aftershocks in the ETAS model gives more accurate estimates of the true background rate, and more realistic expectations for long-term seismicity patterns.

  1. Accounting for orphaned aftershocks in the earthquake background rate

    NASA Astrophysics Data System (ADS)

    van der Elst, Nicholas J.

    2017-11-01

    Aftershocks often occur within cascades of triggered seismicity in which each generation of aftershocks triggers an additional generation, and so on. The rate of earthquakes in any particular generation follows Omori's law, going approximately as 1/t. This function decays rapidly, but is heavy-tailed, and aftershock sequences may persist for long times at a rate that is difficult to discriminate from background. It is likely that some apparently spontaneous earthquakes in the observational catalogue are orphaned aftershocks of long-past main shocks. To assess the relative proportion of orphaned aftershocks in the apparent background rate, I develop an extension of the ETAS model that explicitly includes the expected contribution of orphaned aftershocks to the apparent background rate. Applying this model to California, I find that the apparent background rate can be almost entirely attributed to orphaned aftershocks, depending on the assumed duration of an aftershock sequence. This implies an earthquake cascade with a branching ratio (the average number of directly triggered aftershocks per main shock) of nearly unity. In physical terms, this implies that very few earthquakes are completely isolated from the perturbing effects of other earthquakes within the fault system. Accounting for orphaned aftershocks in the ETAS model gives more accurate estimates of the true background rate, and more realistic expectations for long-term seismicity patterns.

  2. Foreshock occurrence rates before large earthquakes worldwide

    USGS Publications Warehouse

    Reasenberg, P.A.

    1999-01-01

    Global rates of foreshock occurrence involving shallow M ??? 6 and M ??? 7 mainshocks and M ??? 5 foreshocks were measured, using earthquakes listed in the Harvard CMT catalog for the period 1978-1996. These rates are similar to rates ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide rates were compared to a generic model of earthquake clustering, which is based on patterns of small and moderate aftershocks in California, and were found to exceed the California model by a factor of approximately 2. Significant differences in foreshock rate were found among subsets of earthquakes defined by their focal mechanism and tectonic region, with the rate before thrust events higher and the rate before strike-slip events lower than the worldwide average. Among the thrust events a large majority, composed of events located in shallow subduction zones, registered a high foreshock rate, while a minority, located in continental thrust belts, measured a low rate. These differences may explain why previous surveys have revealed low foreshock rates among thrust events in California (especially southern California), while the worldwide observations suggest the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low rate apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich.

  3. Recurrence of attic cholesteatoma: different methods of estimating recurrence rates.

    PubMed

    Stangerup, S E; Drozdziewicz, D; Tos, M; Hougaard-Jensen, A

    2000-09-01

    One problem in cholesteatoma surgery is recurrence of cholesteatoma, which is reported to vary from 5% to 71%. This great variability can be explained by issues such as the type of cholesteatoma, surgical technique, follow-up rate, length of the postoperative observation period, and statistical method applied. The aim of this study was to illustrate the impact of applying different statistical methods to the same material. Thirty-three children underwent single-stage surgery for attic cholesteatoma during a 15-year period. Thirty patients (94%) attended a re-evaluation. During the observation period of 15 years, recurrence of cholesteatoma occurred in 10 ears. The cumulative total recurrence rate varied from 30% to 67%, depending on the statistical method applied. In conclusion, the choice of statistical method should depend on the number of patients, follow-up rates, length of the postoperative observation period and presence of censored data.

  4. A Comparison of Geodetic and Geologic Rates Prior to Large Strike-Slip Earthquakes: A Diversity of Earthquake-Cycle Behaviors?

    NASA Astrophysics Data System (ADS)

    Dolan, James F.; Meade, Brendan J.

    2017-12-01

    Comparison of preevent geodetic and geologic rates in three large-magnitude (Mw = 7.6-7.9) strike-slip earthquakes reveals a wide range of behaviors. Specifically, geodetic rates of 26-28 mm/yr for the North Anatolian fault along the 1999 MW = 7.6 Izmit rupture are ˜40% faster than Holocene geologic rates. In contrast, geodetic rates of ˜6-8 mm/yr along the Denali fault prior to the 2002 MW = 7.9 Denali earthquake are only approximately half as fast as the latest Pleistocene-Holocene geologic rate of ˜12 mm/yr. In the third example where a sufficiently long pre-earthquake geodetic time series exists, the geodetic and geologic rates along the 2001 MW = 7.8 Kokoxili rupture on the Kunlun fault are approximately equal at ˜11 mm/yr. These results are not readily explicable with extant earthquake-cycle modeling, suggesting that they may instead be due to some combination of regional kinematic fault interactions, temporal variations in the strength of lithospheric-scale shear zones, and/or variations in local relative plate motion rate. Whatever the exact causes of these variable behaviors, these observations indicate that either the ratio of geodetic to geologic rates before an earthquake may not be diagnostic of the time to the next earthquake, as predicted by many rheologically based geodynamic models of earthquake-cycle behavior, or different behaviors characterize different fault systems in a manner that is not yet understood or predictable.

  5. Assessment of tsunami hazard to the U.S. East Coast using relationships between submarine landslides and earthquakes

    USGS Publications Warehouse

    ten Brink, Uri S.; Lee, H.J.; Geist, E.L.; Twichell, D.

    2009-01-01

    Submarine landslides along the continental slope of the U.S. Atlantic margin are potential sources for tsunamis along the U.S. East coast. The magnitude of potential tsunamis depends on the volume and location of the landslides, and tsunami frequency depends on their recurrence interval. However, the size and recurrence interval of submarine landslides along the U.S. Atlantic margin is poorly known. Well-studied landslide-generated tsunamis in other parts of the world have been shown to be associated with earthquakes. Because the size distribution and recurrence interval of earthquakes is generally better known than those for submarine landslides, we propose here to estimate the size and recurrence interval of submarine landslides from the size and recurrence interval of earthquakes in the near vicinity of the said landslides. To do so, we calculate maximum expected landslide size for a given earthquake magnitude, use recurrence interval of earthquakes to estimate recurrence interval of landslide, and assume a threshold landslide size that can generate a destructive tsunami. The maximum expected landslide size for a given earthquake magnitude is calculated in 3 ways: by slope stability analysis for catastrophic slope failure on the Atlantic continental margin, by using land-based compilation of maximum observed distance from earthquake to liquefaction, and by using land-based compilation of maximum observed area of earthquake-induced landslides. We find that the calculated distances and failure areas from the slope stability analysis is similar or slightly smaller than the maximum triggering distances and failure areas in subaerial observations. The results from all three methods compare well with the slope failure observations of the Mw = 7.2, 1929 Grand Banks earthquake, the only historical tsunamigenic earthquake along the North American Atlantic margin. The results further suggest that a Mw = 7.5 earthquake (the largest expected earthquake in the eastern U

  6. Earthquake Prediction in Large-scale Faulting Experiments

    NASA Astrophysics Data System (ADS)

    Junger, J.; Kilgore, B.; Beeler, N.; Dieterich, J.

    2004-12-01

    We study repeated earthquake slip of a 2 m long laboratory granite fault surface with approximately homogenous frictional properties. In this apparatus earthquakes follow a period of controlled, constant rate shear stress increase, analogous to tectonic loading. Slip initiates and accumulates within a limited area of the fault surface while the surrounding fault remains locked. Dynamic rupture propagation and slip of the entire fault surface is induced when slip in the nucleating zone becomes sufficiently large. We report on the event to event reproducibility of loading time (recurrence interval), failure stress, stress drop, and precursory activity. We tentatively interpret these variations as indications of the intrinsic variability of small earthquake occurrence and source physics in this controlled setting. We use the results to produce measures of earthquake predictability based on the probability density of repeating occurrence and the reproducibility of near-field precursory strain. At 4 MPa normal stress and a loading rate of 0.0001 MPa/s, the loading time is ˜25 min, with a coefficient of variation of around 10%. Static stress drop has a similar variability which results almost entirely from variability of the final (rather than initial) stress. Thus, the initial stress has low variability and event times are slip-predictable. The variability of loading time to failure is comparable to the lowest variability of recurrence time of small repeating earthquakes at Parkfield (Nadeau et al., 1998) and our result may be a good estimate of the intrinsic variability of recurrence. Distributions of loading time can be adequately represented by a log-normal or Weibel distribution but long term prediction of the next event time based on probabilistic representation of previous occurrence is not dramatically better than for field-observed small- or large-magnitude earthquake datasets. The gradually accelerating precursory aseismic slip observed in the region of

  7. Significance of stress transfer in time-dependent earthquake probability calculations

    USGS Publications Warehouse

    Parsons, T.

    2005-01-01

    A sudden change in stress is seen to modify earthquake rates, but should it also revise earthquake probability? Data used to derive input parameters permits an array of forecasts; so how large a static stress change is require to cause a statistically significant earthquake probability change? To answer that question, effects of parameter and philosophical choices are examined through all phases of sample calculations, Drawing at random from distributions of recurrence-aperiodicity pairs identifies many that recreate long paleoseismic and historic earthquake catalogs. Probability density funtions built from the recurrence-aperiodicity pairs give the range of possible earthquake forecasts under a point process renewal model. Consequences of choices made in stress transfer calculations, such as different slip models, fault rake, dip, and friction are, tracked. For interactions among large faults, calculated peak stress changes may be localized, with most of the receiving fault area changed less than the mean. Thus, to avoid overstating probability change on segments, stress change values should be drawn from a distribution reflecting the spatial pattern rather than using the segment mean. Disparity resulting from interaction probability methodology is also examined. For a fault with a well-understood earthquake history, a minimum stress change to stressing rate ratio of 10:1 to 20:1 is required to significantly skew probabilities with >80-85% confidence. That ratio must be closer to 50:1 to exceed 90-95% confidence levels. Thus revision to earthquake probability is achievable when a perturbing event is very close to the fault in question or the tectonic stressing rate is low.

  8. Earthquake stress drop and laboratory-inferred interseismic strength recovery

    USGS Publications Warehouse

    Beeler, N.M.; Hickman, S.H.; Wong, T.-F.

    2001-01-01

    We determine the scaling relationships between earthquake stress drop and recurrence interval tr that are implied by laboratory-measured fault strength. We assume that repeating earthquakes can be simulated by stick-slip sliding using a spring and slider block model. Simulations with static/kinetic strength, time-dependent strength, and rate- and state-variable-dependent strength indicate that the relationship between loading velocity and recurrence interval can be adequately described by the power law VL ??? trn, where n=-1. Deviations from n=-1 arise from second order effects on strength, with n>-1 corresponding to apparent time-dependent strengthening and n<-1 corresponding to weakening. Simulations with rate and state-variable equations show that dynamic shear stress drop ????d scales with recurrence as d????d/dlntr ??? ??e(b-a), where ??e is the effective normal stress, ??=??/??e, and (a-b)=d??ss/dlnV is the steady-state slip rate dependence of strength. In addition, accounting for seismic energy radiation, we suggest that the static shear stress drop ????s scales as d????s/dlntr ??? ??e(1+??)(b-a), where ?? is the fractional overshoot. The variation of ????s with lntr for earthquake stress drops is somewhat larger than implied by room temperature laboratory values of ?? and b-a. However, the uncertainty associated with the seismic data is large and the discrepancy between the seismic observations and the rate of strengthening predicted by room temperature experiments is less than an order of magnitude. Copyright 2001 by the American Geophysical Union.

  9. Modeling earthquake rate changes in Oklahoma and Arkansas: possible signatures of induced seismicity

    USGS Publications Warehouse

    Llenos, Andrea L.; Michael, Andrew J.

    2013-01-01

    The rate of ML≥3 earthquakes in the central and eastern United States increased beginning in 2009, particularly in Oklahoma and central Arkansas, where fluid injection has occurred. We find evidence that suggests these rate increases are man‐made by examining the rate changes in a catalog of ML≥3 earthquakes in Oklahoma, which had a low background seismicity rate before 2009, as well as rate changes in a catalog of ML≥2.2 earthquakes in central Arkansas, which had a history of earthquake swarms prior to the start of injection in 2009. In both cases, stochastic epidemic‐type aftershock sequence models and statistical tests demonstrate that the earthquake rate change is statistically significant, and both the background rate of independent earthquakes and the aftershock productivity must increase in 2009 to explain the observed increase in seismicity. This suggests that a significant change in the underlying triggering process occurred. Both parameters vary, even when comparing natural to potentially induced swarms in Arkansas, which suggests that changes in both the background rate and the aftershock productivity may provide a way to distinguish man‐made from natural earthquake rate changes. In Arkansas we also compare earthquake and injection well locations, finding that earthquakes within 6 km of an active injection well tend to occur closer together than those that occur before, after, or far from active injection. Thus, like a change in productivity, a change in interevent distance distribution may also be an indicator of induced seismicity.

  10. Prospective Evaluation of the Global Earthquake Activity Rate Model (GEAR1) Earthquake Forecast: Preliminary Results

    NASA Astrophysics Data System (ADS)

    Strader, Anne; Schorlemmer, Danijel; Beutin, Thomas

    2017-04-01

    The Global Earthquake Activity Rate Model (GEAR1) is a hybrid seismicity model, constructed from a loglinear combination of smoothed seismicity from the Global Centroid Moment Tensor (CMT) earthquake catalog and geodetic strain rates (Global Strain Rate Map, version 2.1). For the 2005-2012 retrospective evaluation period, GEAR1 outperformed both parent strain rate and smoothed seismicity forecasts. Since 1. October 2015, GEAR1 has been prospectively evaluated by the Collaboratory for the Study of Earthquake Predictability (CSEP) testing center. Here, we present initial one-year test results of the GEAR1, GSRM and GSRM2.1, as well as localized evaluation of GEAR1 performance. The models were evaluated on the consistency in number (N-test), spatial (S-test) and magnitude (M-test) distribution of forecasted and observed earthquakes, as well as overall data consistency (CL-, L-tests). Performance at target earthquake locations was compared between models using the classical paired T-test and its non-parametric equivalent, the W-test, to determine if one model could be rejected in favor of another at the 0.05 significance level. For the evaluation period from 1. October 2015 to 1. October 2016, the GEAR1, GSRM and GSRM2.1 forecasts pass all CSEP likelihood tests. Comparative test results show statistically significant improvement of GEAR1 performance over both strain rate-based forecasts, both of which can be rejected in favor of GEAR1. Using point process residual analysis, we investigate the spatial distribution of differences in GEAR1, GSRM and GSRM2 model performance, to identify regions where the GEAR1 model should be adjusted, that could not be inferred from CSEP test results. Furthermore, we investigate whether the optimal combination of smoothed seismicity and strain rates remains stable over space and time.

  11. Dating Informed Correlations and Large Earthquake Recurrence at the Hokuri Creek Paleoseismic Site, Alpine Fault, South Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Biasi, G. P.; Clark, K.; Berryman, K. R.; Cochran, U. A.; Prior, C.

    2010-12-01

    -correlate sections at the site. Within a series of dates from a section, ordering with intrinsic precision of the dates indicates an uncertainty at event horizons on the order of 50 years, while the transitions from peat to silt indicating an earthquake are separated by several times this amount. The effect is to create a stair-stepping date sequence that often allows us to link sections and improve dating resolution in both sections. The combined section provides clear evidence for at least 18 earthquake-induced cycles. Event recurrence would be about 390 years in a simple average. Internal evidence and close examination of date sequences provide preliminary indications of as many as 22 earthquakes could be represented at Hokuri Creek, and a recurrence interval of ~320 years. Both sequences indicate a middle sequence from 3800 to 1000 BC in which recurrence intervals are resolvably longer than average. Variability in recurrence is relatively small - relatively few intervals are even >1.5x the average. This indicates that large earthquakes on the Alpine Fault of South Island, New Zealand are best fit by a time-predictable model.

  12. 2D Simulations of Earthquake Cycles at a Subduction Zone Based on a Rate and State Friction Law -Effects of Pore Fluid Pressure Changes-

    NASA Astrophysics Data System (ADS)

    Mitsui, Y.; Hirahara, K.

    2006-12-01

    There have been a lot of studies that simulate large earthquakes occurring quasi-periodically at a subduction zone, based on the laboratory-derived rate-and-state friction law [eg. Kato and Hirasawa (1997), Hirose and Hirahara (2002)]. All of them assume that pore fluid pressure in the fault zone is constant. However, in the fault zone, pore fluid pressure changes suddenly, due to coseismic pore dilatation [Marone (1990)] and thermal pressurization [Mase and Smith (1987)]. If pore fluid pressure drops and effective normal stress rises, fault slip is decelerated. Inversely, if pore fluid pressure rises and effective normal stress drops, fault slip is accelerated. The effect of pore fluid may cause slow slip events and low-frequency tremor [Kodaira et al. (2004), Shelly et al. (2006)]. For a simple spring model, how pore dilatation affects slip instability was investigated [Segall and Rice (1995), Sleep (1995)]. When the rate of the slip becomes high, pore dilatation occurs and pore pressure drops, and the rate of the slip is restrained. Then the inflow of pore fluid recovers the pore pressure. We execute 2D earthquake cycle simulations at a subduction zone, taking into account such changes of pore fluid pressure following Segall and Rice (1995), in addition to the numerical scheme in Kato and Hirasawa (1997). We do not adopt hydrostatic pore pressure but excess pore pressure for initial condition, because upflow of dehydrated water seems to exist at a subduction zone. In our model, pore fluid is confined to the fault damage zone and flows along the plate interface. The smaller the flow rate is, the later pore pressure recovers. Since effective normal stress keeps larger, the fault slip is decelerated and stress drop becomes smaller. Therefore the smaller flow rate along the fault zone leads to the shorter earthquake recurrence time. Thus, not only the frictional parameters and the subduction rate but also the fault zone permeability affects the recurrence time of

  13. Determining earthquake recurrence intervals from deformational structures in young lacustrine sediments

    USGS Publications Warehouse

    Sims, John D.

    1975-01-01

    Examination of the silty sediments in the lower Van Normal reservoir after the 1971 San Fernando, California earthquake revealed three zones of deformational structures in the 1-m-thick sequence of sediments exposed over about 2 km2 of the reservoir bottom. These zones are correlated with moderate earthquakes that shook the San Fernando area in 1930, 1952, and 1971. The success of this study, coupled with the experimental formation of deformational structures similar to those of the Van Norman reservoir, led to a search for similar structures in Pleistocene and Holocene lakes and lake sediments in other seismically active areas. Thus, studies have been started in Pleistocene and Holocene silty and sandy lake sediments in the Imperial Valley, southeastern California; Clear Lake, in northern California; and the Puget Sound area of Washington. The Imperial Valley study has yielded spectacular results: five zones of structures in the upper 10 m of Late Holocene sediments near Brawley have been correlated over an area of approximately 100 km2, using natural outcrops. These structures are similar to those of the Van Norman reservoir and are interpreted to represent at least five moderate to large earthquakes that affected the southern Imperial Valley area during Late Holocene time. The Clear Lake study has provided ambiguous results with respect to determination of earthquake recurrence intervals because the cores studied are in clayey rich in organic material sediments that have low liquefaction potential. A study of Late Pleistocene varved glacio-lacustrine sediments has been started in the Puget Sound area of Washington, and thirteen sites have been examined. One has yielded 18.75 m of sediments that contains 1,804 varves and fourteen deformed zones interpreted as being caused by earthquake, because they are identical to structures formed experimentally by simulated seismic shaking. Correlation of deformational structures with seismic events is based on:(1) proximity

  14. Use of recurrence plot and recurrence quantification analysis in Taiwan unemployment rate time series

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Shing

    2011-04-01

    The aim of the article is to answer the question if the Taiwan unemployment rate dynamics is generated by a non-linear deterministic dynamic process. This paper applies a recurrence plot and recurrence quantification approach based on the analysis of non-stationary hidden transition patterns of the unemployment rate of Taiwan. The case study uses the time series data of the Taiwan’s unemployment rate during the period from 1978/01 to 2010/06. The results show that recurrence techniques are able to identify various phases in the evolution of unemployment transition in Taiwan.

  15. Strain rates, stress markers and earthquake clustering (Invited)

    NASA Astrophysics Data System (ADS)

    Fry, B.; Gerstenberger, M.; Abercrombie, R. E.; Reyners, M.; Eberhart-Phillips, D. M.

    2013-12-01

    The 2010-present Canterbury earthquakes comprise a well-recorded sequence in a relatively low strain-rate shallow crustal region. We present new scientific results to test the hypothesis that: Earthquake sequences in low-strain rate areas experience high stress drop events, low-post seismic relaxation, and accentuated seismic clustering. This hypothesis is based on a physical description of the aftershock process in which the spatial distribution of stress accumulation and stress transfer are controlled by fault strength and orientation. Following large crustal earthquakes, time dependent forecasts are often developed by fitting parameters defined by Omori's aftershock decay law. In high-strain rate areas, simple forecast models utilizing a single p-value fit observed aftershock sequences well. In low-strain rate areas such as Canterbury, assumptions of simple Omori decay may not be sufficient to capture the clustering (sub-sequence) nature exhibited by the punctuated rise in activity following significant child events. In Canterbury, the moment release is more clustered than in more typical Omori sequences. The individual earthquakes in these clusters also exhibit somewhat higher stress drops than in the average crustal sequence in high-strain rate regions, suggesting the earthquakes occur on strong Andersonian-oriented faults, possibly juvenile or well-healed . We use the spectral ratio procedure outlined in (Viegas et al., 2010) to determine corner frequencies and Madariaga stress-drop values for over 800 events in the sequence. Furthermore, we will discuss the relevance of tomographic results of Reyners and Eberhart-Phillips (2013) documenting post-seismic stress-driven fluid processes following the three largest events in the sequence as well as anisotropic patterns in surface wave tomography (Fry et al., 2013). These tomographic studies are both compatible with the hypothesis, providing strong evidence for the presence of widespread and hydrated regional

  16. Global observation of Omori-law decay in the rate of triggered earthquakes

    NASA Astrophysics Data System (ADS)

    Parsons, T.

    2001-12-01

    Triggered earthquakes can be large, damaging, and lethal as evidenced by the 1999 shocks in Turkey and the 2001 events in El Salvador. In this study, earthquakes with M greater than 7.0 from the Harvard CMT catalog are modeled as dislocations to calculate shear stress changes on subsequent earthquake rupture planes near enough to be affected. About 61% of earthquakes that occurred near the main shocks are associated with calculated shear stress increases, while ~39% are associated with shear stress decreases. If earthquakes associated with calculated shear stress increases are interpreted as triggered, then such events make up at least 8% of the CMT catalog. Globally, triggered earthquakes obey an Omori-law rate decay that lasts between ~7-11 years after the main shock. Earthquakes associated with calculated shear stress increases occur at higher rates than background up to 240 km away from the main-shock centroid. Earthquakes triggered by smaller quakes (foreshocks) also obey Omori's law, which is one of the few time-predictable patterns evident in the global occurrence of earthquakes. These observations indicate that earthquake probability calculations which include interactions from previous shocks should incorporate a transient Omori-law decay with time. In addition, a very simple model using the observed global rate change with time and spatial distribution of triggered earthquakes can be applied to immediately assess the likelihood of triggered earthquakes following large events, and can be in place until more sophisticated analyses are conducted.

  17. The use of earthquake rate changes as a stress meter at Kilauea volcano.

    PubMed

    Dieterich, J; Cayol, V; Okubo, P

    2000-11-23

    Stress changes in the Earth's crust are generally estimated from model calculations that use near-surface deformation as an observational constraint. But the widespread correlation of changes of earthquake activity with stress has led to suggestions that stress changes might be calculated from earthquake occurrence rates obtained from seismicity catalogues. Although this possibility has considerable appeal, because seismicity data are routinely collected and have good spatial and temporal resolution, the method has not yet proven successful, owing to the non-linearity of earthquake rate changes with respect to both stress and time. Here, however, we present two methods for inverting earthquake rate data to infer stress changes, using a formulation for the stress- and time-dependence of earthquake rates. Application of these methods at Kilauea volcano, in Hawaii, yields good agreement with independent estimates, indicating that earthquake rates can provide a practical remote-sensing stress meter.

  18. Earthquake correlations and networks: A comparative study

    NASA Astrophysics Data System (ADS)

    Krishna Mohan, T. R.; Revathi, P. G.

    2011-04-01

    We quantify the correlation between earthquakes and use the same to extract causally connected earthquake pairs. Our correlation metric is a variation on the one introduced by Baiesi and Paczuski [M. Baiesi and M. Paczuski, Phys. Rev. E EULEEJ1539-375510.1103/PhysRevE.69.06610669, 066106 (2004)]. A network of earthquakes is then constructed from the time-ordered catalog and with links between the more correlated ones. A list of recurrences to each of the earthquakes is identified employing correlation thresholds to demarcate the most meaningful ones in each cluster. Data pertaining to three different seismic regions (viz., California, Japan, and the Himalayas) are comparatively analyzed using such a network model. The distribution of recurrence lengths and recurrence times are two of the key features analyzed to draw conclusions about the universal aspects of such a network model. We find that the unimodal feature of recurrence length distribution, which helps to associate typical rupture lengths with different magnitude earthquakes, is robust across the different seismic regions. The out-degree of the networks shows a hub structure rooted on the large magnitude earthquakes. In-degree distribution is seen to be dependent on the density of events in the neighborhood. Power laws, with two regimes having different exponents, are obtained with recurrence time distribution. The first regime confirms the Omori law for aftershocks while the second regime, with a faster falloff for the larger recurrence times, establishes that pure spatial recurrences also follow a power-law distribution. The crossover to the second power-law regime can be taken to be signaling the end of the aftershock regime in an objective fashion.

  19. Spatial Evaluation and Verification of Earthquake Simulators

    NASA Astrophysics Data System (ADS)

    Wilson, John Max; Yoder, Mark R.; Rundle, John B.; Turcotte, Donald L.; Schultz, Kasey W.

    2017-06-01

    In this paper, we address the problem of verifying earthquake simulators with observed data. Earthquake simulators are a class of computational simulations which attempt to mirror the topological complexity of fault systems on which earthquakes occur. In addition, the physics of friction and elastic interactions between fault elements are included in these simulations. Simulation parameters are adjusted so that natural earthquake sequences are matched in their scaling properties. Physically based earthquake simulators can generate many thousands of years of simulated seismicity, allowing for a robust capture of the statistical properties of large, damaging earthquakes that have long recurrence time scales. Verification of simulations against current observed earthquake seismicity is necessary, and following past simulator and forecast model verification methods, we approach the challenges in spatial forecast verification to simulators; namely, that simulator outputs are confined to the modeled faults, while observed earthquake epicenters often occur off of known faults. We present two methods for addressing this discrepancy: a simplistic approach whereby observed earthquakes are shifted to the nearest fault element and a smoothing method based on the power laws of the epidemic-type aftershock (ETAS) model, which distributes the seismicity of each simulated earthquake over the entire test region at a decaying rate with epicentral distance. To test these methods, a receiver operating characteristic plot was produced by comparing the rate maps to observed m>6.0 earthquakes in California since 1980. We found that the nearest-neighbor mapping produced poor forecasts, while the ETAS power-law method produced rate maps that agreed reasonably well with observations.

  20. A reliable simultaneous representation of seismic hazard and of ground shaking recurrence

    NASA Astrophysics Data System (ADS)

    Peresan, A.; Panza, G. F.; Magrin, A.; Vaccari, F.

    2015-12-01

    Different earthquake hazard maps may be appropriate for different purposes - such as emergency management, insurance and engineering design. Accounting for the lower occurrence rate of larger sporadic earthquakes may allow to formulate cost-effective policies in some specific applications, provided that statistically sound recurrence estimates are used, which is not typically the case of PSHA (Probabilistic Seismic Hazard Assessment). We illustrate the procedure to associate the expected ground motions from Neo-deterministic Seismic Hazard Assessment (NDSHA) to an estimate of their recurrence. Neo-deterministic refers to a scenario-based approach, which allows for the construction of a broad range of earthquake scenarios via full waveforms modeling. From the synthetic seismograms the estimates of peak ground acceleration, velocity and displacement, or any other parameter relevant to seismic engineering, can be extracted. NDSHA, in its standard form, defines the hazard computed from a wide set of scenario earthquakes (including the largest deterministically or historically defined credible earthquake, MCE) and it does not supply the frequency of occurrence of the expected ground shaking. A recent enhanced variant of NDSHA that reliably accounts for recurrence has been developed and it is applied to the Italian territory. The characterization of the frequency-magnitude relation can be performed by any statistically sound method supported by data (e.g. multi-scale seismicity model), so that a recurrence estimate is associated to each of the pertinent sources. In this way a standard NDSHA map of ground shaking is obtained simultaneously with the map of the corresponding recurrences. The introduction of recurrence estimates in NDSHA naturally allows for the generation of ground shaking maps at specified return periods. This permits a straightforward comparison between NDSHA and PSHA maps.

  1. Simulate earthquake cycles on the oceanic transform faults in the framework of rate-and-state friction

    NASA Astrophysics Data System (ADS)

    Wei, M.

    2016-12-01

    Progress towards a quantitative and predictive understanding of the earthquake behavior can be achieved by improved understanding of earthquake cycles. However, it is hindered by the long repeat times (100s to 1000s of years) of the largest earthquakes on most faults. At fast-spreading oceanic transform faults, the typical repeating time ranges from 5-20 years, making them a unique tectonic environment for studying the earthquake cycle. One important observation on OTFs is the quasi-periodicity and the spatial-temporal clustering of large earthquakes: same fault segment ruptured repeatedly at a near constant interval and nearby segments ruptured during a short time period. This has been observed on the Gofar and Discovery faults in the East Pacific Rise. Between 1992 and 2014, five clusters of M6 earthquakes occurred on the Gofar and Discovery fault system with recurrence intervals of 4-6 years. Each cluster consisted of a westward migration of seismicity from the Discovery to Gofar segment within a 2-year period, providing strong evidence for spatial-temporal clustering of large OTFs earthquakes. I simulated earthquake cycles of oceanic transform fault in the framework of rate-and-state friction, motivated by the observations at the Gofar and Discovery faults. I focus on a model with two seismic segments, each 20 km long and 5 km wide, separated by an aseismic segment of 10 km wide. This geometry is set based on aftershock locations of the 2008 M6.0 earthquake on Gofar. The repeating large earthquake on both segments are reproduced with similar magnitude as observed. I set the state parameter differently for the two seismic segments so initially they are not synchornized. Results also show that synchronization of the two seismic patches can be achieved after several earthquake cycles when the effective normal stress or the a-b parameter is smaller than surrounding aseismic areas, both having reduced the resistance to seismic rupture in the VS segment. These

  2. Earthquake potential in California-Nevada implied by correlation of strain rate and seismicity

    USGS Publications Warehouse

    Zeng, Yuehua; Petersen, Mark D.; Shen, Zheng-Kang

    2018-01-01

    Rock mechanics studies and dynamic earthquake simulations show that patterns of seismicity evolve with time through (1) accumulation phase, (2) localization phase, and (3) rupture phase. We observe a similar pattern of changes in seismicity during the past century across California and Nevada. To quantify these changes, we correlate GPS strain rates with seismicity. Earthquakes of M > 6.5 are collocated with regions of highest strain rates. By contrast, smaller magnitude earthquakes of M ≥ 4 show clear spatiotemporal changes. From 1933 to the late 1980s, earthquakes of M ≥ 4 were more diffused and broadly distributed in both high and low strain rate regions (accumulation phase). From the late 1980s to 2016, earthquakes were more concentrated within the high strain rate areas focused on the major fault strands (localization phase). In the same time period, the rate of M > 6.5 events also increased significantly in the high strain rate areas. The strong correlation between current strain rate and the later period of seismicity indicates that seismicity is closely related to the strain rate. The spatial patterns suggest that before the late 1980s, the strain rate field was also broadly distributed because of the stress shadows from previous large earthquakes. As the deformation field evolved out of the shadow in the late 1980s, strain has refocused on the major fault systems and we are entering a period of increased risk for large earthquakes in California.

  3. Earthquake Potential in California-Nevada Implied by Correlation of Strain Rate and Seismicity

    NASA Astrophysics Data System (ADS)

    Zeng, Yuehua; Petersen, Mark D.; Shen, Zheng-Kang

    2018-02-01

    Rock mechanics studies and dynamic earthquake simulations show that patterns of seismicity evolve with time through (1) accumulation phase, (2) localization phase, and (3) rupture phase. We observe a similar pattern of changes in seismicity during the past century across California and Nevada. To quantify these changes, we correlate GPS strain rates with seismicity. Earthquakes of M > 6.5 are collocated with regions of highest strain rates. By contrast, smaller magnitude earthquakes of M ≥ 4 show clear spatiotemporal changes. From 1933 to the late 1980s, earthquakes of M ≥ 4 were more diffused and broadly distributed in both high and low strain rate regions (accumulation phase). From the late 1980s to 2016, earthquakes were more concentrated within the high strain rate areas focused on the major fault strands (localization phase). In the same time period, the rate of M > 6.5 events also increased significantly in the high strain rate areas. The strong correlation between current strain rate and the later period of seismicity indicates that seismicity is closely related to the strain rate. The spatial patterns suggest that before the late 1980s, the strain rate field was also broadly distributed because of the stress shadows from previous large earthquakes. As the deformation field evolved out of the shadow in the late 1980s, strain has refocused on the major fault systems and we are entering a period of increased risk for large earthquakes in California.

  4. RECURRENCE RATES OF OCULAR TOXOPLASMOSIS DURING PREGNANCY

    PubMed Central

    Braakenburg, Arthur M.D.; Crespi, Catherine M.; Holland, Gary N.; Wu, Sheng; Yu, Fei; Rothova, Aniki

    2014-01-01

    Purpose To investigate whether recurrence rates of ocular toxoplasmosis are higher during pregnancy among women of childbearing age. Design Retrospective longitudinal cohort study. Methods We reviewed medical records of all women seen at a university eye clinic (Utrecht, Netherlands) during episodes of active toxoplasmic retinochoroiditis that occurred while the women were of childbearing age (16–42 years). Each woman was sent a questionnaire requesting information regarding all pregnancies and episodes of ocular toxoplasmosis, whether or not episodes were observed at the eye clinic. Conditional fixed-effects Poisson regression was used to model incident rate ratios of recurrence during pregnant versus non-pregnant intervals, adjusted for potential confounders, including age at time of active toxoplasmic retinochoroiditis and interval since last episode of active disease, which are known to influence risk of recurrence. Results Questionnaires were returned by 50 (58%) of 86 women, 34 of whom had 69 pregnancies during 584 person-years of study. There were 128 episodes of ocular toxoplasmosis during the study period (6 during pregnancy). First episodes of ocular toxoplasmosis occurred between ages 9.6 and 38.5 years. Youngest age at pregnancy was 16.1 years; oldest age at childbirth was 40.9 years. Incident rate ratios for pregnant versus non-pregnant intervals were in the direction of lower recurrence rates during pregnancy, with point estimates of 0.54 and 0.75 under two different approaches, but ratios were not significantly different from the null value (p-values of 0.16 and 0.55). Conclusions Recurrence rates of ocular toxoplasmosis are likely not higher during pregnancy, in contrast to traditional beliefs. PMID:24412127

  5. Recurrence rates of ocular toxoplasmosis during pregnancy.

    PubMed

    Braakenburg, Arthur M D; Crespi, Catherine M; Holland, Gary N; Wu, Sheng; Yu, Fei; Rothova, Aniki

    2014-04-01

    To investigate whether recurrence rates of ocular toxoplasmosis are higher during pregnancy in women of childbearing age. Retrospective longitudinal cohort study. We reviewed medical records of all women seen at a university eye clinic (Utrecht, Netherlands) during episodes of active toxoplasmic retinochoroiditis that occurred while the women were of childbearing age (16-42 years). Each woman was sent a questionnaire requesting information regarding all pregnancies and episodes of ocular toxoplasmosis, whether or not episodes were observed at the eye clinic. Conditional fixed-effects Poisson regression was used to model incidence rate ratios of recurrence during pregnant versus nonpregnant intervals, adjusted for potential confounders, including age at time of active toxoplasmic retinochoroiditis and interval since last episode of active disease, which are known to influence risk for recurrence. Questionnaires were returned by 50 (58%) of 86 women, 34 of whom had had 69 pregnancies during 584 person-years of study. There were 128 episodes of ocular toxoplasmosis during the study period (6 during pregnancy). First episodes of ocular toxoplasmosis occurred between ages 9.6 and 38.5 years. The youngest age at pregnancy was 16.1 years; the oldest age at childbirth was 40.9 years. The incidence-rate ratios for pregnant versus nonpregnant intervals were in the direction of lower recurrence rates during pregnancy, with point estimates of 0.54 and 0.75 under 2 different approaches, but the ratios were not significantly different from the null value (P values of 0.16 and 0.55). Recurrence rates of ocular toxoplasmosis are probably not higher during pregnancy, in contrast to traditional beliefs. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. High Attenuation Rate for Shallow, Small Earthquakes in Japan

    NASA Astrophysics Data System (ADS)

    Si, Hongjun; Koketsu, Kazuki; Miyake, Hiroe

    2017-09-01

    We compared the attenuation characteristics of peak ground accelerations (PGAs) and velocities (PGVs) of strong motion from shallow, small earthquakes that occurred in Japan with those predicted by the equations of Si and Midorikawa (J Struct Constr Eng 523:63-70, 1999). The observed PGAs and PGVs at stations far from the seismic source decayed more rapidly than the predicted ones. The same tendencies have been reported for deep, moderate, and large earthquakes, but not for shallow, moderate, and large earthquakes. This indicates that the peak values of ground motion from shallow, small earthquakes attenuate more steeply than those from shallow, moderate or large earthquakes. To investigate the reason for this difference, we numerically simulated strong ground motion for point sources of M w 4 and 6 earthquakes using a 2D finite difference method. The analyses of the synthetic waveforms suggested that the above differences are caused by surface waves, which are predominant at stations far from the seismic source for shallow, moderate earthquakes but not for shallow, small earthquakes. Thus, although loss due to reflection at the boundaries of the discontinuous Earth structure occurs in all shallow earthquakes, the apparent attenuation rate for a moderate or large earthquake is essentially the same as that of body waves propagating in a homogeneous medium due to the dominance of surface waves.

  7. Lake sediment records as earthquake catalogues: A compilation from Swiss lakes - Limitations and possibilities

    NASA Astrophysics Data System (ADS)

    Kremer, Katrina; Reusch, Anna; Wirth, Stefanie B.; Anselmetti, Flavio S.; Girardclos, Stéphanie; Strasser, Michael

    2016-04-01

    Intraplate settings are characterized by low deformation rates and recurrence intervals of strong earthquakes that often exceed the time span covered by instrumental records. Switzerland, as an example for such settings, shows a low instrumentally recorded seismicity, in contrast to strong earthquakes (e.g. 1356 Basel earthquake, Mw=6.6 and 1601 Unterwalden earthquake, Mw=5.9) mentioned in the historical archives. As such long recurrence rates do not allow for instrumental identification of earthquake sources of these strong events, and as intense geomorphologic alterations prevent preservation of surface expressions of faults, the knowledge of active faults is very limited. Lake sediments are sensitive to seismic shaking and thus, can be used to extend the regional earthquake catalogue if the sedimentary deposits or deformation structures can be linked to an earthquake. Single lake records allow estimating local intensities of shaking while multiple lake records can furthermore be used to compare temporal and spatial distribution of earthquakes. In this study, we compile a large dataset of dated sedimentary event deposits recorded in Swiss lakes available from peer-reviewed publications and unpublished master theses. We combine these data in order to detect large prehistoric regional earthquake events or periods of intense shaking that might have affected multiple lake settings. In a second step, using empirical seismic attenuation equations, we test if lake records can be used to reconstruct magnitudes and epicentres of identified earthquakes.

  8. Recurrent Holocene movement on the Susitna Glacier Thrust Fault: The structure that initiated the Mw 7.9 Denali Fault earthquake, central Alaska

    USGS Publications Warehouse

    Personius, Stephen; Crone, Anthony J.; Burns, Patricia A.; Reitman, Nadine G.

    2017-01-01

    We conducted a trench investigation and analyzed pre‐ and postearthquake topography to determine the timing and size of prehistoric surface ruptures on the Susitna Glacier fault (SGF), the thrust fault that initiated the 2002 Mw 7.9 Denali fault earthquake sequence in central Alaska. In two of our three hand‐excavated trenches, we found clear evidence for a single pre‐2002 earthquake (penultimate earthquake [PE]) and determined an age of 2210±420  cal. B.P. (2σ) for this event. We used structure‐from‐motion software to create a pre‐2002‐earthquake digital surface model (DSM) from 1:62,800‐scale aerial photography taken in 1980 and compared this DSM with postearthquake 5‐m/pixel Interferometric Synthetic Aperature Radar topography taken in 2010. Topographic profiles measured from the pre‐earthquake DSM show features that we interpret as fault and fold scarps. These landforms were about the same size as those formed in 2002, so we infer that the PE was similar in size to the initial (Mw 7.2) subevent of the 2002 sequence. A recurrence interval of 2270 yrs and dip slip of ∼4.8  m yield a single‐interval slip rate of ∼1.8  mm/yr. The lack of evidence for pre‐PE deformation indicates probable episodic (clustering) behavior on the SGF that may be related to strain migration among other similarly oriented thrust faults that together accommodate shortening south of the Denali fault. We suspect that slip‐partitioned thrust‐triggered earthquakes may be a common occurrence on the Denali fault system, but documenting the frequency of such events will be very difficult, given the lack of long‐term paleoseismic records, the number of potential thrust‐earthquake sources, and the pervasive glacial erosion in the region.

  9. Implementation into earthquake sequence simulations of a rate- and state-dependent friction law incorporating pressure solution creep

    NASA Astrophysics Data System (ADS)

    Noda, H.

    2016-05-01

    Pressure solution creep (PSC) is an important elementary process in rock friction at high temperatures where solubilities of rock-forming minerals are significantly large. It significantly changes the frictional resistance and enhances time-dependent strengthening. A recent microphysical model for PSC-involved friction of clay-quartz mixtures, which can explain a transition between dilatant and non-dilatant deformation (d-nd transition), was modified here and implemented in dynamic earthquake sequence simulations. The original model resulted in essentially a kind of rate- and state-dependent friction (RSF) law, but assumed a constant friction coefficient for clay resulting in zero instantaneous rate dependency in the dilatant regime. In this study, an instantaneous rate dependency for the clay friction coefficient was introduced, consistent with experiments, resulting in a friction law suitable for earthquake sequence simulations. In addition, a term for time-dependent strengthening due to PSC was added which makes the friction law logarithmically rate-weakening in the dilatant regime. The width of the zone in which clasts overlap or, equivalently, the interface porosity involved in PSC plays a role as the state variable. Such a concrete physical meaning of the state variable is a great advantage in future modelling studies incorporating other physical processes such as hydraulic effects. Earthquake sequence simulations with different pore pressure distributions demonstrated that excess pore pressure at depth causes deeper rupture propagation with smaller slip per event and a shorter recurrence interval. The simulated ruptures were arrested a few kilometres below the point of pre-seismic peak stress at the d-nd transition and did not propagate spontaneously into the region of pre-seismic non-dilatant deformation. PSC weakens the fault against slow deformation and thus such a region cannot produce a dynamic stress drop. Dynamic rupture propagation further down to

  10. Influence of fluctuations of historic water bodies on fault stability and earthquake recurrence interval: The Dead Sea Rift as a case study

    NASA Astrophysics Data System (ADS)

    Belferman, Mariana; Katsman, Regina; Agnon, Amotz; Ben-Avraham, Zvi

    2017-04-01

    Despite the global, social and scientific impact of earthquakes, their triggering mechanisms remain often poorly defined. We suggest that dynamic changes in the levels of the historic water bodies occupying tectonic depressions at the Dead Sea Rift cause significant variations in the shallow crustal stress field and affect local fault systems in a way that may promote or suppress earthquakes. This mechanism and its spatial and temporal scales differ from those in tectonically-driven deformations. We use analytical and numerical poroelastic models to simulate immediate and delayed seismic responses resulting from the observed historic water level changes. The role of variability in the poroelastic and the elastic properties of the rocks composing the upper crust in inducing or retarding deformations under a strike-slip faulting regime is studied. The solution allows estimating a possible reduction in a seismic recurrence interval. Considering the historic water level fluctuation, our preliminary simulations show a promising agreement with paleo-seismic rates identified in the field.

  11. Summary of November 2010 meeting to evaluate turbidite data for constraining the recurrence parameters of great Cascadia earthquakes for the update of national seismic hazard maps

    USGS Publications Warehouse

    Frankel, Arthur D.

    2011-01-01

    , 1996), which were the basis for seismic provisions in the 2000 International Building Code. These hazard maps used the paleoseismic studies to constrain the recurrence rate of great CSZ earthquakes. Goldfinger and his colleagues have since collected many more deep ocean cores and done extensive analysis on the turbidite deposits that they identified in the cores (Goldfinger and others, 2003, 2008, in press; Goldfinger, 2011). Using their dating of the sediments and correlation of features in the logs of density and magnetic susceptibility between cores, they developed a detailed chronology of great earthquakes along the CSZ for the past 10,000 years (Goldfinger and others, in press). These correlations consist of attempting to match the peaks and valleys in logs of density and magnetic susceptibility between cores separated, in some cases, by hundreds of kilometers. Based on this work, Goldfinger and others (2003, 2008, in press) proposed that the turbidite evidence indicated the occurrence of great earthquakes (Mw 8) that only ruptured the southern portion of the CSZ, as well as earthquakes with about Mw 9 that ruptured the entire length of the CSZ. For the southernmost portion of the CSZ, Goldfinger and others (in press) proposed a recurrence time of Mw 8 or larger earthquakes of about 230 years. This proposed recurrence time was shorter than the 500 year time that was incorporated in one scenario in the NSHM’s. It is important to note that the hazard maps of 1996 and later also included a scenario or set of scenarios with a shorter recurrence time for Mw 8 earthquakes, using rupture zones that are distributed along the length of the CSZ (Frankel and others, 1996; Petersen and others, 2008). Originally, this scenario was meant to correspond to the idea that some of the 500-year averaged ruptures seen in the paleoseismic evidence could have been a series of Mw 8 earthquakes that occurred over a short period of time (a few decades), rather than Mw 9 earthquakes

  12. Aseismic transient during the 2010-2014 seismic swarm: evidence for longer recurrence of M ≥ 6.5 earthquakes in the Pollino gap (Southern Italy)?

    PubMed

    Cheloni, Daniele; D'Agostino, Nicola; Selvaggi, Giulio; Avallone, Antonio; Fornaro, Gianfranco; Giuliani, Roberta; Reale, Diego; Sansosti, Eugenio; Tizzani, Pietro

    2017-04-12

    In actively deforming regions, crustal deformation is accommodated by earthquakes and through a variety of transient aseismic phenomena. Here, we study the 2010-2014 Pollino (Southern Italy) swarm sequence (main shock M W 5.1) located within the Pollino seismic gap, by analysing the surface deformation derived from Global Positioning System and Synthetic Aperture Radar data. Inversions of geodetic time series show that a transient slip, with the same mechanism of the main shock, started about 3-4 months before the main shock and lasted almost one year, evolving through time with acceleration phases that correlate with the rate of seismicity. The moment released by the transient slip is equivalent to M W 5.5, significantly larger than the seismic moment release revealing therefore that a significant fraction of the overall deformation is released aseismically. Our findings suggest that crustal deformation in the Pollino gap is accommodated by infrequent "large" earthquakes (M W  ≥ 6.5) and by aseismic episodes releasing a significant fraction of the accrued strain. Lower strain rates, relative to the adjacent Southern Apennines, and a mixed seismic/aseismic strain release are in favour of a longer recurrence for large magnitude earthquakes in the Pollino gap.

  13. Distribution and Characteristics of Repeating Earthquakes in Northern California

    NASA Astrophysics Data System (ADS)

    Waldhauser, F.; Schaff, D. P.; Zechar, J. D.; Shaw, B. E.

    2012-12-01

    show burst-like behavior with mean recurrence times smaller than one month. 5% of the RES have mean recurrence times greater than one year and include more than 10 earthquakes. Earthquakes in the 50 most periodic sequences (CV<0.2) do not appear to be predictable by either time- or slip-predictable models, consistent with previous findings. We demonstrate that changes in recurrence intervals of repeating earthquakes can be routinely monitored. This is especially important for sequences with CV~0, as they may indicate changes in the loading rate. We also present results from retrospective forecast experiments based on near-real time hazard functions.

  14. Triggering of repeating earthquakes in central California

    USGS Publications Warehouse

    Wu, Chunquan; Gomberg, Joan; Ben-Naim, Eli; Johnson, Paul

    2014-01-01

    Dynamic stresses carried by transient seismic waves have been found capable of triggering earthquakes instantly in various tectonic settings. Delayed triggering may be even more common, but the mechanisms are not well understood. Catalogs of repeating earthquakes, earthquakes that recur repeatedly at the same location, provide ideal data sets to test the effects of transient dynamic perturbations on the timing of earthquake occurrence. Here we employ a catalog of 165 families containing ~2500 total repeating earthquakes to test whether dynamic perturbations from local, regional, and teleseismic earthquakes change recurrence intervals. The distance to the earthquake generating the perturbing waves is a proxy for the relative potential contributions of static and dynamic deformations, because static deformations decay more rapidly with distance. Clear changes followed the nearby 2004 Mw6 Parkfield earthquake, so we study only repeaters prior to its origin time. We apply a Monte Carlo approach to compare the observed number of shortened recurrence intervals following dynamic perturbations with the distribution of this number estimated for randomized perturbation times. We examine the comparison for a series of dynamic stress peak amplitude and distance thresholds. The results suggest a weak correlation between dynamic perturbations in excess of ~20 kPa and shortened recurrence intervals, for both nearby and remote perturbations.

  15. The Non-Regularity of Earthquake Recurrence in California: Lessons From Long Paleoseismic Records in Simple vs Complex Fault Regions (Invited)

    NASA Astrophysics Data System (ADS)

    Rockwell, T. K.

    2010-12-01

    A long paleoseismic record at Hog Lake on the central San Jacinto fault (SJF) in southern California documents evidence for 18 surface ruptures in the past 3.8-4 ka. This yields a long-term recurrence interval of about 210 years, consistent with its slip rate of ~16 mm/yr and field observations of 3-4 m of displacement per event. However, during the past 3800 years, the fault has switched from a quasi-periodic mode of earthquake production, during which the recurrence interval is similar to the long-term average, to clustered behavior with the inter-event periods as short as a few decades. There are also some periods as long as 450 years during which there were no surface ruptures, and these periods are commonly followed by one to several closely-timed ruptures. The coefficient of variation (CV) for the timing of these earthquakes is about 0.6 for the past 4000 years (17 intervals). Similar behavior has been observed on the San Andreas Fault (SAF) south of the Transverse Ranges where clusters of earthquakes have been followed by periods of lower seismic production, and the CV is as high as 0.7 for some portions of the fault. In contrast, the central North Anatolian Fault (NAF) in Turkey, which ruptured in 1944, appears to have produced ruptures with similar displacement at fairly regular intervals for the past 1600 years. With a CV of 0.16 for timing, and close to 0.1 for displacement, the 1944 rupture segment near Gerede appears to have been both periodic and characteristic. The SJF and SAF are part of a broad plate boundary system with multiple parallel strands with significant slip rates. Additional faults lay to the east (Eastern California shear zone) and west (faults of the LA basin and southern California Borderland), which makes the southern SAF system a complex and broad plate boundary zone. In comparison, the 1944 rupture section of the NAF is simple, straight and highly localized, which contrasts with the complex system of parallel faults in southern

  16. Thermomechanical earthquake cycle simulations with rate-and-state friction and nonlinear viscoelasticity

    NASA Astrophysics Data System (ADS)

    Allison, K. L.; Dunham, E. M.

    2017-12-01

    We simulate earthquake cycles on a 2D strike-slip fault, modeling both rate-and-state fault friction and an off-fault nonlinear power-law rheology. The power-law rheology involves an effective viscosity that is a function of temperature and stress, and therefore varies both spatially and temporally. All phases of the earthquake cycle are simulated, allowing the model to spontaneously generate earthquakes, and to capture frictional afterslip and postseismic and interseismic viscous flow. We investigate the interaction between fault slip and bulk viscous flow, using experimentally-based flow laws for quartz-diorite in the crust and olivine in the mantle, representative of the Mojave Desert region in Southern California. We first consider a suite of three linear geotherms which are constant in time, with dT/dz = 20, 25, and 30 K/km. Though the simulations produce very different deformation styles in the lower crust, ranging from significant interseismc fault creep to purely bulk viscous flow, they have almost identical earthquake recurrence interval, nucleation depth, and down-dip coseismic slip limit. This indicates that bulk viscous flow and interseismic fault creep load the brittle crust similarly. The simulations also predict unrealistically high stresses in the upper crust, resulting from the fact that the lower crust and upper mantle are relatively weak far from the fault, and from the relatively small role that basal tractions on the base of the crust play in the force balance of the lithosphere. We also find that for the warmest model, the effective viscosity varies by an order of magnitude in the interseismic period, whereas for the cooler models it remains roughly constant. Because the rheology is highly sensitive to changes in temperature, in addition to the simulations with constant temperature we also consider the effect of heat generation. We capture both frictional heat generation and off-fault viscous shear heating, allowing these in turn to alter the

  17. Space-Time Earthquake Rate Models for One-Year Hazard Forecasts in Oklahoma

    NASA Astrophysics Data System (ADS)

    Llenos, A. L.; Michael, A. J.

    2017-12-01

    The recent one-year seismic hazard assessments for natural and induced seismicity in the central and eastern US (CEUS) (Petersen et al., 2016, 2017) rely on earthquake rate models based on declustered catalogs (i.e., catalogs with foreshocks and aftershocks removed), as is common practice in probabilistic seismic hazard analysis. However, standard declustering can remove over 90% of some induced sequences in the CEUS. Some of these earthquakes may still be capable of causing damage or concern (Petersen et al., 2015, 2016). The choices of whether and how to decluster can lead to seismicity rate estimates that vary by up to factors of 10-20 (Llenos and Michael, AGU, 2016). Therefore, in order to improve the accuracy of hazard assessments, we are exploring ways to make forecasts based on full, rather than declustered, catalogs. We focus on Oklahoma, where earthquake rates began increasing in late 2009 mainly in central Oklahoma and ramped up substantially in 2013 with the expansion of seismicity into northern Oklahoma and southern Kansas. We develop earthquake rate models using the space-time Epidemic-Type Aftershock Sequence (ETAS) model (Ogata, JASA, 1988; Ogata, AISM, 1998; Zhuang et al., JASA, 2002), which characterizes both the background seismicity rate as well as aftershock triggering. We examine changes in the model parameters over time, focusing particularly on background rate, which reflects earthquakes that are triggered by external driving forces such as fluid injection rather than other earthquakes. After the model parameters are fit to the seismicity data from a given year, forecasts of the full catalog for the following year can then be made using a suite of 100,000 ETAS model simulations based on those parameters. To evaluate this approach, we develop pseudo-prospective yearly forecasts for Oklahoma from 2013-2016 and compare them with the observations using standard Collaboratory for the Study of Earthquake Predictability tests for consistency.

  18. Laboratory-based maximum slip rates in earthquake rupture zones and radiated energy

    USGS Publications Warehouse

    McGarr, A.; Fletcher, Joe B.; Boettcher, M.; Beeler, N.; Boatwright, J.

    2010-01-01

    Laboratory stick-slip friction experiments indicate that peak slip rates increase with the stresses loading the fault to cause rupture. If this applies also to earthquake fault zones, then the analysis of rupture processes is simplified inasmuch as the slip rates depend only on the local yield stress and are independent of factors specific to a particular event, including the distribution of slip in space and time. We test this hypothesis by first using it to develop an expression for radiated energy that depends primarily on the seismic moment and the maximum slip rate. From laboratory results, the maximum slip rate for any crustal earthquake, as well as various stress parameters including the yield stress, can be determined based on its seismic moment and the maximum slip within its rupture zone. After finding that our new equation for radiated energy works well for laboratory stick-slip friction experiments, we used it to estimate radiated energies for five earthquakes with magnitudes near 2 that were induced in a deep gold mine, an M 2.1 repeating earthquake near the San Andreas Fault Observatory at Depth (SAFOD) site and seven major earthquakes in California and found good agreement with energies estimated independently from spectra of local and regional ground-motion data. Estimates of yield stress for the earthquakes in our study range from 12 MPa to 122 MPa with a median of 64 MPa. The lowest value was estimated for the 2004 M 6 Parkfield, California, earthquake whereas the nearby M 2.1 repeating earthquake, as recorded in the SAFOD pilot hole, showed a more typical yield stress of 64 MPa.

  19. Interseismic coupling, seismic potential and earthquake recurrence on the southern front of the Eastern Alps (NE Italy)

    NASA Astrophysics Data System (ADS)

    Cheloni, Daniele; D'Agostino, Nicola; Selvaggi, Giulio

    2014-05-01

    The interaction of the African, Arabian, and Eurasia plates in the "greater" Mediterranean region yields to a broad range of tectonic processes including active subduction, continental collision, major continental strike-slip faults and "intra-plate" mountain building. In this puzzling region the convergence between Adria microplate and Eurasia plate is partly or entirely absorbed within the South-Eastern Alps, where the Adriatic lithosphere underthrusts beneath the mountain belt. Historical seismicity and instrumentally recorded earthquakes show thrust faulting on north-dipping low-angle faults in agreement with geological observations of active mountain building and active fold growing at the foothills of the South-Eastern Alps. In this study, we use continuous GPS observations to document the geodetic strain accumulation across the South-Eastern Alps (NE Italy). We estimate the pattern of interseismic coupling on the intra-continental collision north-dipping thrust faults that separate the Eastern Alps and the Venetian-Friulian plain using the back-slip approach and discuss the seismic potential and earthquake recurrence. Comparison between the rigid-rotation predicted motion and the shortening observed across the studied area indicates that the South-Eastern Alpine thrust front absorbs about 80% of the total convergence rate between the Adria microplate and Eurasia plate. The modelled thrust fault is currently locked from the surface to a depth of approximately 10 km. The transition zone between locked and creeping portions of the fault roughly corresponds with the belt of microseismicity parallel and to the north of the mountain front. The estimated moment deficit rate is 1.27±0.14×10^17 Nm/yr. The comparison between the estimated moment deficit and that released historically by the earthquakes suggests that to account for the moment deficit the following two factors or their combination should be considered: (1) a significant part of the observed

  20. Holocene slip rates along the San Andreas Fault System in the San Gorgonio Pass and implications for large earthquakes in southern California

    NASA Astrophysics Data System (ADS)

    Heermance, Richard V.; Yule, Doug

    2017-06-01

    The San Gorgonio Pass (SGP) in southern California contains a 40 km long region of structural complexity where the San Andreas Fault (SAF) bifurcates into a series of oblique-slip faults with unknown slip history. We combine new 10Be exposure ages (Qt4: 8600 (+2100, -2200) and Qt3: 5700 (+1400, -1900) years B.P.) and a radiocarbon age (1260 ± 60 years B.P.) from late Holocene terraces with scarp displacement of these surfaces to document a Holocene slip rate of 5.7 (+2.7, -1.5) mm/yr combined across two faults. Our preferred slip rate is 37-49% of the average slip rates along the SAF outside the SGP (i.e., Coachella Valley and San Bernardino sections) and implies that strain is transferred off the SAF in this area. Earthquakes here most likely occur in very large, throughgoing SAF events at a lower recurrence than elsewhere on the SAF, so that only approximately one third of SAF ruptures penetrate or originate in the pass.Plain Language SummaryHow large are <span class="hlt">earthquakes</span> on the southern San Andreas Fault? The answer to this question depends on whether or not the <span class="hlt">earthquake</span> is contained only along individual fault sections, such as the Coachella Valley section north of Palm Springs, or the rupture crosses multiple sections including the area through the San Gorgonio Pass. We have determined the age and offset of faulted stream deposits within the San Gorgonio Pass to document slip <span class="hlt">rates</span> of these faults over the last 10,000 years. Our results indicate a long-term slip <span class="hlt">rate</span> of 6 mm/yr, which is almost 1/2 of the <span class="hlt">rates</span> east and west of this area. These new <span class="hlt">rates</span>, combined with faulted geomorphic surfaces, imply that large magnitude <span class="hlt">earthquakes</span> must occasionally rupture a 300 km length of the San Andreas Fault from the Salton Sea to the Mojave Desert. Although many ( 65%) <span class="hlt">earthquakes</span> along the southern San Andreas Fault likely do not rupture through the pass, our new results suggest that large >Mw 7.5 <span class="hlt">earthquakes</span> are possible</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li class="active"><span>5</span></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_5 --> <div id="page_6" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="101"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176199','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176199"><span>Characterizing potentially induced <span class="hlt">earthquake</span> <span class="hlt">rate</span> changes in the Brawley Seismic Zone, southern California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Llenos, Andrea L.; Michael, Andrew J.</p> <p>2016-01-01</p> <p>The Brawley seismic zone (BSZ), in the Salton trough of southern California, has a history of <span class="hlt">earthquake</span> swarms and geothermal energy exploitation. Some <span class="hlt">earthquake</span> <span class="hlt">rate</span> changes may have been induced by fluid extraction and injection activity at local geothermal fields, particularly at the North Brawley Geothermal Field (NBGF) and at the Salton Sea Geothermal Field (SSGF). We explore this issue by examining <span class="hlt">earthquake</span> <span class="hlt">rate</span> changes and interevent distance distributions in these fields. In Oklahoma and Arkansas, where considerable wastewater injection occurs, increases in background seismicity <span class="hlt">rate</span> and aftershock productivity and decreases in interevent distance were indicative of fluid‐injection‐induced seismicity. Here, we test if similar changes occur that may be associated with fluid injection and extraction in geothermal areas. We use stochastic epidemic‐type aftershock sequence models to detect changes in the underlying seismogenic processes, shown by statistically significant changes in the model parameters. The most robust model changes in the SSGF roughly occur when large changes in net fluid production occur, but a similar correlation is not seen in the NBGF. Also, although both background seismicity <span class="hlt">rate</span> and aftershock productivity increased for fluid‐injection‐induced <span class="hlt">earthquake</span> <span class="hlt">rate</span> changes in Oklahoma and Arkansas, the background <span class="hlt">rate</span> increases significantly in the BSZ only, roughly corresponding with net fluid production <span class="hlt">rate</span> increases. Moreover, in both fields the interevent spacing does not change significantly during active energy projects. This suggests that, although geothermal field activities in a tectonically active region may not significantly change the physics of <span class="hlt">earthquake</span> interactions, <span class="hlt">earthquake</span> <span class="hlt">rates</span> may still be driven by fluid injection or extraction <span class="hlt">rates</span>, particularly in the SSGF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://geology.utah.gov/hazards/technical-information/paleoseismology-of-utah-series/','USGSPUBS'); return false;" href="https://geology.utah.gov/hazards/technical-information/paleoseismology-of-utah-series/"><span>Holocene surface-faulting <span class="hlt">earthquakes</span> at the Spring Lake and North Creek Sites on the Wasatch Fault Zone: Evidence for complex rupture of the Nephi Segment</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Duross, Christopher; Hylland, Michael D.; Hiscock, Adam; Personius, Stephen; Briggs, Richard; Gold, Ryan D.; Beukelman, Gregg; McDonald, Geg N; Erickson, Ben; McKean, Adam; Angster, Steve; King, Roselyn; Crone, Anthony J.; Mahan, Shannon</p> <p>2017-01-01</p> <p>The Nephi segment of the Wasatch fault zone (WFZ) comprises two fault strands, the northern and southern strands, which have evidence of <span class="hlt">recurrent</span> late Holocene surface-faulting <span class="hlt">earthquakes</span>. We excavated paleoseismic trenches across these strands to refine and expand their Holocene <span class="hlt">earthquake</span> chronologies; improve estimates of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>, displacement, and fault slip <span class="hlt">rate</span>; and assess whether the strands rupture separately or synchronously in large <span class="hlt">earthquakes</span>. Paleoseismic data from the Spring Lake site expand the Holocene record of <span class="hlt">earthquakes</span> on the northern strand: at least five to seven <span class="hlt">earthquakes</span> ruptured the Spring Lake site at 0.9 ± 0.2 ka (2σ), 2.9 ± 0.7 ka, 4.0 ± 0.5 ka, 4.8 ± 0.8 ka, 5.7 ± 0.8 ka, 6.6 ± 0.7 ka, and 13.1 ± 4.0 ka, yielding a Holocene mean <span class="hlt">recurrence</span> of ~1.2–1.5 kyr and vertical slip <span class="hlt">rate</span> of ~0.5–0.8 mm/yr. Paleoseismic data from the North Creek site help refine the Holocene <span class="hlt">earthquake</span> chronology for the southern strand: at least five <span class="hlt">earthquakes</span> ruptured the North Creek site at 0.2 ± 0.1 ka (2σ), 1.2 ± 0.1 ka, 2.6 ± 0.9 ka, 4.0 ± 0.1 ka, and 4.7 ± 0.7 ka, yielding a mean <span class="hlt">recurrence</span> of 1.1–1.3 kyr and vertical slip <span class="hlt">rate</span> of ~1.9–2.0 mm/yr. We compare these Spring Lake and North Creek data with previous paleoseismic data for the Nephi segment and report late Holocene mean <span class="hlt">recurrence</span> intervals of ~1.0–1.2 kyr for the northern strand and ~1.1–1.3 kyr for the southern strand. The northern and southern strands have similar late Holocene <span class="hlt">earthquake</span> histories, which allow for models of both independent and synchronous rupture. However, considering the <span class="hlt">earthquake</span> timing probabilities and per-event vertical displacements, we have the greatest confidence in the simultaneous rupture of the strands, including rupture of one strand with spillover rupture to the other. Ultimately, our results improve the surface-faulting <span class="hlt">earthquake</span> history of the Nephi segment and enhance our understanding of how structural barriers</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.6265W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.6265W"><span>Quantified sensitivity of lakes to record historic <span class="hlt">earthquakes</span>: Implications for paleoseismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wilhelm, Bruno; Nomade, Jerome; Crouzet, Christian; Litty, Camille; Belle, Simon; Rolland, Yann; Revel, Marie; Courboulex, Françoise; Arnaud, Fabien; Anselmetti, Flavio S.</p> <p>2015-04-01</p> <p> the sedimentation <span class="hlt">rate</span>. Indeed, an increasing sedimentation <span class="hlt">rate</span> implies an increasing sensitivity to <span class="hlt">earthquake</span> shaking with a apparent threshold of 0.5-1 mm.yr-1. To improve the paleoseismic event catalogue, further studies in small alpine-type lakes are needed. They should (i) focus on lake systems with sedimentation <span class="hlt">rates</span> ≥ 1mm.yr-1, (ii) consider inter-lakes correlation over less than 100 km for epicentral <span class="hlt">earthquake</span> MSK intensity < IX and (iii) control carefully that no significant change in sedimentation <span class="hlt">rates</span> occurs within the record, which could falsify <span class="hlt">recurrence</span>-interval assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70037700','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70037700"><span>Evidence for a twelfth large <span class="hlt">earthquake</span> on the southern hayward fault in the past 1900 years</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Lienkaemper, J.J.; Williams, P.L.; Guilderson, T.P.</p> <p>2010-01-01</p> <p>We present age and stratigraphic evidence for an additional paleoearthquake at the Tyson Lagoon site. The acquisition of 19 additional radiocarbon dates and the inclusion of this additional event has resolved a large age discrepancy in our earlier <span class="hlt">earthquake</span> chronology. The age of event E10 was previously poorly constrained, thus increasing the uncertainty in the mean <span class="hlt">recurrence</span> interval (RI), a critical factor in seismic hazard evaluation. Reinspection of many trench logs revealed substantial evidence suggesting that an additional <span class="hlt">earthquake</span> occurred between E10 and E9 within unit u45. Strata in older u45 are faulted in the main fault zone and overlain by scarp colluviums in two locations.We conclude that an additional surfacerupturing event (E9.5) occurred between E9 and E10. Since 91 A.D. (??40 yr, 1??), 11 paleoearthquakes preceded the M 6:8 <span class="hlt">earthquake</span> in 1868, yielding a mean RI of 161 ?? 65 yr (1??, standard deviation of <span class="hlt">recurrence</span> intervals). However, the standard error of the mean (SEM) is well determined at ??10 yr. Since ~1300 A.D., the mean <span class="hlt">rate</span> has increased slightly, but is indistinguishable from the overall <span class="hlt">rate</span> within the uncertainties. <span class="hlt">Recurrence</span> for the 12-event sequence seems fairly regular: the coefficient of variation is 0.40, and it yields a 30-yr <span class="hlt">earthquake</span> probability of 29%. The apparent regularity in timing implied by this <span class="hlt">earthquake</span> chronology lends support for the use of time-dependent renewal models rather than assuming a random process to forecast <span class="hlt">earthquakes</span>, at least for the southern Hayward fault.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204..753T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204..753T"><span>Detection of change points in underlying <span class="hlt">earthquake</span> <span class="hlt">rates</span>, with application to global mega-<span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Touati, Sarah; Naylor, Mark; Main, Ian</p> <p>2016-02-01</p> <p>The recent spate of mega-<span class="hlt">earthquakes</span> since 2004 has led to speculation of an underlying change in the global `background' <span class="hlt">rate</span> of large events. At a regional scale, detecting changes in background <span class="hlt">rate</span> is also an important practical problem for operational forecasting and risk calculation, for example due to volcanic processes, seismicity induced by fluid injection or withdrawal, or due to redistribution of Coulomb stress after natural large events. Here we examine the general problem of detecting changes in background <span class="hlt">rate</span> in <span class="hlt">earthquake</span> catalogues with and without correlated events, for the first time using the Bayes factor as a discriminant for models of varying complexity. First we use synthetic Poisson (purely random) and Epidemic-Type Aftershock Sequence (ETAS) models (which also allow for <span class="hlt">earthquake</span> triggering) to test the effectiveness of many standard methods of addressing this question. These fall into two classes: those that evaluate the relative likelihood of different models, for example using Information Criteria or the Bayes Factor; and those that evaluate the probability of the observations (including extreme events or clusters of events) under a single null hypothesis, for example by applying the Kolmogorov-Smirnov and `runs' tests, and a variety of Z-score tests. The results demonstrate that the effectiveness among these tests varies widely. Information Criteria worked at least as well as the more computationally expensive Bayes factor method, and the Kolmogorov-Smirnov and runs tests proved to be the relatively ineffective in reliably detecting a change point. We then apply the methods tested to events at different thresholds above magnitude M ≥ 7 in the global <span class="hlt">earthquake</span> catalogue since 1918, after first declustering the catalogue. This is most effectively done by removing likely correlated events using a much lower magnitude threshold (M ≥ 5), where triggering is much more obvious. We find no strong evidence that the background <span class="hlt">rate</span> of large</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19860035481&hterms=recurrence+sequences&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Drecurrence%2Bsequences','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19860035481&hterms=recurrence+sequences&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Drecurrence%2Bsequences"><span>Surface deformation associated with the November 23, 1977, Caucete, Argentina, <span class="hlt">earthquake</span> sequence</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kadinsky-Cade, K.; Reilinger, R.; Isacks, B.</p> <p>1985-01-01</p> <p>The 1977 Caucete (San Juan) <span class="hlt">earthquake</span> considered in the present paper occurred near the Sierra Pie de Palo in the Sierras Pampeanas tectonic province of western Argentina. In the study reported, coseismic surface deformation is combined with seismic observations (main shock and aftershocks, both teleseismic and local data) to place constraints on the geometry and slip of the main fault responsible for the 1977 <span class="hlt">earthquake</span>. The implications of the 1977 event for long-term crustal shortening and <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span> in this region are also discussed. It is concluded that the 1977 Caucete <span class="hlt">earthquake</span> was accompanied by more than 1 m of vertical uplift.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S44B..01I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S44B..01I"><span>Increases in seismicity <span class="hlt">rate</span> in the Tokyo Metropolitan area after the 2011 Tohoku <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ishibe, T.; Satake, K.; Sakai, S.; Shimazaki, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.</p> <p>2013-12-01</p> <p>Abrupt increases in seismicity <span class="hlt">rate</span> have been observed in the Kanto region, where the Tokyo Metropolitan area is located, after the 2011 off the Pacific coast of Tohoku <span class="hlt">earthquake</span> (M9.0) on March 11, 2011. They are well explained by the static increases in the Coulomb Failure Function (ΔCFF) imparted by the gigantic thrusting while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration, post-seismic slip) may also contribute the <span class="hlt">rate</span> changes. Because of various types of <span class="hlt">earthquakes</span> with different focal mechanisms occur in the Kanto region, the receiver faults for the calculation of ΔCFF were assumed to be two nodal planes of small <span class="hlt">earthquakes</span> before and after the Tohoku <span class="hlt">earthquake</span>. The regions where seismicity <span class="hlt">rate</span> increased after the Tohoku <span class="hlt">earthquake</span> well correlate with concentration on positive ΔCFF (i.e., southwestern Ibaraki and northern Chiba prefectures where intermediate-depth <span class="hlt">earthquakes</span> occur, and in the shallow crust of western Kanagawa, eastern Shizuoka, and southeastern Yamanashi including the Izu and Hakone regions). The seismicity <span class="hlt">rate</span> has increased since March 11, 2011 with respect to the Epidemic Type Aftershock Sequence (ETAS) model (Ogata, 1988), suggesting that the <span class="hlt">rate</span> increase was due to the stress increase by the Tohoku <span class="hlt">earthquake</span>. Furthermore, the z-values immediately after the Tohoku <span class="hlt">earthquake</span> show the minimum values during the recent 10 years, indicating significant increases in seismicity <span class="hlt">rate</span>. At intermediate depth, abrupt increases in thrust faulting <span class="hlt">earthquakes</span> are well consistent with the Coulomb stress increase. At shallow depth, the <span class="hlt">earthquakes</span> with the T-axes of roughly NE-SW were activated probably due to the E-W extension of the overriding continental plate, and this is also well explained by the Coulomb stress increase. However, the activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased <span class="hlt">rate</span> of seismicity in the southwestern</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.738...92D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.738...92D"><span>Paleoseismic history and slip <span class="hlt">rate</span> along the Sapanca-Akyazı segment of the 1999 İzmit <span class="hlt">earthquake</span> rupture (Mw = 7.4) of the North Anatolian Fault (Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dikbaş, Aynur; Akyüz, H. Serdar; Meghraoui, Mustapha; Ferry, Matthieu; Altunel, Erhan; Zabcı, Cengiz; Langridge, Robert; Yalçıner, Cahit Çağlar</p> <p>2018-07-01</p> <p>The Sapanca-Akyazı segment (SAS) is located on western part of the North Anatolian Fault (NAF) of Turkey. It was ruptured together with four other segments during the 17th August 1999 İzmit <span class="hlt">earthquake</span> (Mw = 7.4) which caused 145-km-long surface rupture in the east Marmara region. We conducted geomorphological investigations and 2D-3D paleoseismic trenching at 3 different sites near the Sakarya River along the SAS to obtain new data for the timing of past <span class="hlt">earthquakes</span> and slip <span class="hlt">rate</span> of this section of the NAF. Detailed investigations using Ground Penetrating Radar on the western bank of the Sakarya River reveal 18.5 ± 0.5 m of right-lateral cumulative offset of an alluvial terrace dated as 850 ± 11 years BP using Optically Stimulated Luminescence. The analysis of trench data from the three different sites of the SAS indicates the occurrence of four surface rupturing past <span class="hlt">earthquakes</span> including the 1999 İzmit <span class="hlt">earthquake</span>. According to the radiocarbon dating, these paleo-<span class="hlt">earthquakes</span> can be correlated with the 1719 CE, 1567 CE, and 1037 CE historical <span class="hlt">earthquakes</span> and suggest an average <span class="hlt">recurrence</span> period between 273 and 322 years. The total dextral offset, the age of trench units and the terrace deposits together suggest a 22 ± 3 mm/yr slip <span class="hlt">rate</span> for this portion of the NAF.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018E%26PSL.481....9M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018E%26PSL.481....9M"><span>Larger <span class="hlt">earthquakes</span> recur more periodically: New insights in the megathrust <span class="hlt">earthquake</span> cycle from lacustrine turbidite records in south-central Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moernaut, J.; Van Daele, M.; Fontijn, K.; Heirman, K.; Kempf, P.; Pino, M.; Valdebenito, G.; Urrutia, R.; Strasser, M.; De Batist, M.</p> <p>2018-01-01</p> <p>Historical and paleoseismic records in south-central Chile indicate that giant <span class="hlt">earthquakes</span> on the subduction megathrust - such as in AD1960 (Mw 9.5) - reoccur on average every ∼300 yr. Based on geodetic calculations of the interseismic moment accumulation since AD1960, it was postulated that the area already has the potential for a Mw 8 <span class="hlt">earthquake</span>. However, to estimate the probability of such a great <span class="hlt">earthquake</span> to take place in the short term, one needs to frame this hypothesis within the long-term <span class="hlt">recurrence</span> pattern of megathrust <span class="hlt">earthquakes</span> in south-central Chile. Here we present two long lacustrine records, comprising up to 35 <span class="hlt">earthquake</span>-triggered turbidites over the last 4800 yr. Calibration of turbidite extent with historical <span class="hlt">earthquake</span> intensity reveals a different macroseismic intensity threshold (≥VII1/2 vs. ≥VI1/2) for the generation of turbidites at the coring sites. The strongest <span class="hlt">earthquakes</span> (≥VII1/2) have longer <span class="hlt">recurrence</span> intervals (292 ±93 yrs) than <span class="hlt">earthquakes</span> with intensity of ≥VI1/2 (139 ± 69yr). Moreover, distribution fitting and the coefficient of variation (CoV) of inter-event times indicate that the stronger <span class="hlt">earthquakes</span> recur in a more periodic way (CoV: 0.32 vs. 0.5). Regional correlation of our multi-threshold shaking records with coastal paleoseismic data of complementary nature (tsunami, coseismic subsidence) suggests that the intensity ≥VII1/2 events repeatedly ruptured the same part of the megathrust over a distance of at least ∼300 km and can be assigned to Mw ≥ 8.6. We hypothesize that a zone of high plate locking - identified by geodetic studies and large slip in AD 1960 - acts as a dominant regional asperity, on which elastic strain builds up over several centuries and mostly gets released in quasi-periodic great and giant <span class="hlt">earthquakes</span>. Our paleo-records indicate that Poissonian <span class="hlt">recurrence</span> models are inadequate to describe large megathrust <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> in south-central Chile. Moreover, they show an enhanced</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S53A2749I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S53A2749I"><span>Inter-plate aseismic slip on the subducting plate boundaries estimated from repeating <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Igarashi, T.</p> <p>2015-12-01</p> <p>Sequences of repeating <span class="hlt">earthquakes</span> are caused by repeating slips of small patches surrounded by aseismic slip areas at plate boundary zones. Recently, they have been detected in many regions. In this study, I detected repeating <span class="hlt">earthquakes</span> which occurred in Japan and the world by using seismograms observed in the Japanese seismic network, and investigated the space-time characteristics of inter-plate aseismic slip on the subducting plate boundaries. To extract repeating <span class="hlt">earthquakes</span>, I calculate cross-correlation coefficients of band-pass filtering seismograms at each station following Igarashi [2010]. I used two data-set based on USGS catalog for about 25 years from May 1990 and JMA catalog for about 13 years from January 2002. As a result, I found many sequences of repeating <span class="hlt">earthquakes</span> in the subducting plate boundaries of the Andaman-Sumatra-Java and Japan-Kuril-Kamchatka-Aleutian subduction zones. By applying the scaling relations among a seismic moment, <span class="hlt">recurrence</span> interval and slip proposed by Nadeau and Johnson [1998], they indicate the space-time changes of inter-plate aseismic slips. Pairs of repeating <span class="hlt">earthquakes</span> with the longest time interval occurred in the Solomon Islands area and the <span class="hlt">recurrence</span> interval was about 18.5 years. The estimated slip-<span class="hlt">rate</span> is about 46 mm/year, which correspond to about half of the relative plate motion in this area. Several sequences with fast slip-<span class="hlt">rates</span> correspond to the post-seismic slips after the 2004 Sumatra-Andaman <span class="hlt">earthquake</span> (M9.0), the 2006 Kuril <span class="hlt">earthquake</span> (M8.3), the 2007 southern Sumatra <span class="hlt">earthquake</span> (M8.5), and the 2011 Tohoku-oki <span class="hlt">earthquake</span> (M9.0). The database of global repeating <span class="hlt">earthquakes</span> enables the comparison of the inter-plate aseismic slips of various plate boundary zones of the world. I believe that I am likely to detect more sequences by extending analysis periods in the area where they were not found in this analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T43D3041W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T43D3041W"><span>Relative Contributions of Geothermal Pumping and Long-Term <span class="hlt">Earthquake</span> <span class="hlt">Rate</span> to Seismicity at California Geothermal Fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weiser, D. A.; Jackson, D. D.</p> <p>2015-12-01</p> <p>In a tectonically active area, a definitive discrimination between geothermally-induced and tectonic <span class="hlt">earthquakes</span> is difficult to achieve. We focus our study on California's 11 major geothermal fields: Amedee, Brawley, Casa Diablo, Coso, East Mesa, The Geysers, Heber, Litchfield, Salton Sea, Susanville, and Wendel. The Geysers geothermal field is the world's largest geothermal energy producer. California's Department of Oil Gas and Geothermal Resources provides field-wide monthly injection and production volumes for each of these sites, which allows us to study the relationship between geothermal pumping activities and seismicity. Since many of the geothermal fields began injecting and producing before nearby seismic stations were installed, we use smoothed seismicity since 1932 from the ANSS catalog as a proxy for tectonic <span class="hlt">earthquake</span> <span class="hlt">rate</span>. We examine both geothermal pumping and long-term <span class="hlt">earthquake</span> <span class="hlt">rate</span> as factors that may control <span class="hlt">earthquake</span> <span class="hlt">rate</span>. Rather than focusing only on the largest <span class="hlt">earthquake</span>, which is essentially a random occurrence in time, we examine how M≥4 <span class="hlt">earthquake</span> <span class="hlt">rate</span> density (probability per unit area, time, and magnitude) varies for each field. We estimate relative contributions to the observed <span class="hlt">earthquake</span> <span class="hlt">rate</span> of M≥4 from both a long-term <span class="hlt">earthquake</span> <span class="hlt">rate</span> (Kagan and Jackson, 2010) and pumping activity. For each geothermal field, respective <span class="hlt">earthquake</span> catalogs (NCEDC and SCSN) are complete above at least M3 during the test period (which we tailor to each site). We test the hypothesis that the observed <span class="hlt">earthquake</span> <span class="hlt">rate</span> at a geothermal site during the test period is a linear combination of the long-term seismicity and pumping <span class="hlt">rates</span>. We use a grid search to determine the confidence interval of the weighting parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70027075','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70027075"><span>Changes in crustal seismic deformation <span class="hlt">rates</span> associated with the 1964 Great Alaska <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Doser, D.I.; Ratchkovski, N.A.; Haeussler, Peter J.; Saltus, R.</p> <p>2004-01-01</p> <p>We calculated seismic moment <span class="hlt">rates</span> from crustal <span class="hlt">earthquake</span> information for the upper Cook Inlet region, including Anchorage, Alaska, for the 30 yr prior to and 36 yr following the 1964 Great Alaska <span class="hlt">earthquake</span>. Our results suggest over a factor of 1000 decrease in seismic moment <span class="hlt">rate</span> (in units of dyne centimeters per year) following the 1964 mainshock. We used geologic information on structures within the Cook Inlet basin to estimate a regional geologic moment <span class="hlt">rate</span>, assuming the structures extend to 30 km depth and have near-vertical dips. The geologic moment <span class="hlt">rates</span> could underestimate the true <span class="hlt">rates</span> by up to 70% since it is difficult determine the amount of horizontal offset that has occurred along many structures within the basin. Nevertheless, the geologic moment <span class="hlt">rate</span> is only 3-7 times lower than the pre-1964 seismic moment <span class="hlt">rate</span>, suggesting the 1964 mainshock has significantly slowed regional crustal deformation. If we compare the geologic moment <span class="hlt">rate</span> to the post-1964 seismic moment <span class="hlt">rate</span>, the moment <span class="hlt">rate</span> deficit over the past 36 yr is equivalent to a moment magnitude 6.6-7.0 <span class="hlt">earthquake</span>. These observed differences in moment <span class="hlt">rates</span> highlight the difficulty in using seismicity in the decades following a large megathrust <span class="hlt">earthquake</span> to adequately characterize long-term crustal deformation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRB..120..326C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRB..120..326C"><span>Synthetic <span class="hlt">earthquake</span> catalogs simulating seismic activity in the Corinth Gulf, Greece, fault system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Console, Rodolfo; Carluccio, Roberto; Papadimitriou, Eleftheria; Karakostas, Vassilis</p> <p>2015-01-01</p> <p>The characteristic <span class="hlt">earthquake</span> hypothesis is the basis of time-dependent modeling of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> on major faults. However, the characteristic <span class="hlt">earthquake</span> hypothesis is not strongly supported by observational data. Few fault segments have long historical or paleoseismic records of individually dated ruptures, and when data and parameter uncertainties are allowed for, the form of the <span class="hlt">recurrence</span> distribution is difficult to establish. This is the case, for instance, of the Corinth Gulf Fault System (CGFS), for which documents about strong <span class="hlt">earthquakes</span> exist for at least 2000 years, although they can be considered complete for M ≥ 6.0 only for the latest 300 years, during which only few characteristic <span class="hlt">earthquakes</span> are reported for individual fault segments. The use of a physics-based <span class="hlt">earthquake</span> simulator has allowed the production of catalogs lasting 100,000 years and containing more than 500,000 events of magnitudes ≥ 4.0. The main features of our simulation algorithm are (1) an average slip <span class="hlt">rate</span> released by <span class="hlt">earthquakes</span> for every single segment in the investigated fault system, (2) heuristic procedures for rupture growth and stop, leading to a self-organized <span class="hlt">earthquake</span> magnitude distribution, (3) the interaction between <span class="hlt">earthquake</span> sources, and (4) the effect of minor <span class="hlt">earthquakes</span> in redistributing stress. The application of our simulation algorithm to the CGFS has shown realistic features in time, space, and magnitude behavior of the seismicity. These features include long-term periodicity of strong <span class="hlt">earthquakes</span>, short-term clustering of both strong and smaller events, and a realistic <span class="hlt">earthquake</span> magnitude distribution departing from the Gutenberg-Richter distribution in the higher-magnitude range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018SedG..365...62L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018SedG..365...62L"><span>Sedimentary evidence of historical and prehistorical <span class="hlt">earthquakes</span> along the Venta de Bravo Fault System, Acambay Graben (Central Mexico)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lacan, Pierre; Ortuño, María; Audin, Laurence; Perea, Hector; Baize, Stephane; Aguirre-Díaz, Gerardo; Zúñiga, F. Ramón</p> <p>2018-03-01</p> <p>The Venta de Bravo normal fault is one of the longest structures in the intra-arc fault system of the Trans-Mexican Volcanic Belt. It defines, together with the Pastores Fault, the 80 km long southern margin of the Acambay Graben. We focus on the westernmost segment of the Venta de Bravo Fault and provide new paleoseismological information, evaluate its <span class="hlt">earthquake</span> history, and assess the related seismic hazard. We analyzed five trenches, distributed at three different sites, in which Holocene surface faulting offsets interbedded volcanoclastic, fluvio-lacustrine and colluvial deposits. Despite the lack of known historical destructive <span class="hlt">earthquakes</span> along this fault, we found evidence of at least eight <span class="hlt">earthquakes</span> during the late Quaternary. Our results indicate that this is one of the major seismic sources of the Acambay Graben, capable of producing by itself <span class="hlt">earthquakes</span> with magnitudes (MW) up to 6.9, with a slip <span class="hlt">rate</span> of 0.22-0.24 mm yr- 1 and a <span class="hlt">recurrence</span> interval between 1940 and 2390 years. In addition, a possible multi-fault rupture of the Venta de Bravo Fault together with other faults of the Acambay Graben could result in a MW > 7 <span class="hlt">earthquake</span>. These new slip <span class="hlt">rates</span>, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, and estimation of slips per event help advance our understanding of the seismic hazard posed by the Venta de Bravo Fault and provide new parameters for further hazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27161897','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27161897"><span>Possible scenarios for occurrence of M ~ 7 interplate <span class="hlt">earthquakes</span> prior to and following the 2011 Tohoku-Oki <span class="hlt">earthquake</span> based on numerical simulation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Nakata, Ryoko; Hori, Takane; Hyodo, Mamoru; Ariyoshi, Keisuke</p> <p>2016-05-10</p> <p>We show possible scenarios for the occurrence of M ~ 7 interplate <span class="hlt">earthquakes</span> prior to and following the M ~ 9 <span class="hlt">earthquake</span> along the Japan Trench, such as the 2011 Tohoku-Oki <span class="hlt">earthquake</span>. One such M ~ 7 <span class="hlt">earthquake</span> is so-called the Miyagi-ken-Oki <span class="hlt">earthquake</span>, for which we conducted numerical simulations of <span class="hlt">earthquake</span> generation cycles by using realistic three-dimensional (3D) geometry of the subducting Pacific Plate. In a number of scenarios, the time interval between the M ~ 9 <span class="hlt">earthquake</span> and the subsequent Miyagi-ken-Oki <span class="hlt">earthquake</span> was equal to or shorter than the average <span class="hlt">recurrence</span> interval during the later stage of the M ~ 9 <span class="hlt">earthquake</span> cycle. The scenarios successfully reproduced important characteristics such as the <span class="hlt">recurrence</span> of M ~ 7 <span class="hlt">earthquakes</span>, coseismic slip distribution, afterslip distribution, the largest foreshock, and the largest aftershock of the 2011 <span class="hlt">earthquake</span>. Thus, these results suggest that we should prepare for future M ~ 7 <span class="hlt">earthquakes</span> in the Miyagi-ken-Oki segment even though this segment recently experienced large coseismic slip in 2011.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4861985','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4861985"><span>Possible scenarios for occurrence of M ~ 7 interplate <span class="hlt">earthquakes</span> prior to and following the 2011 Tohoku-Oki <span class="hlt">earthquake</span> based on numerical simulation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Nakata, Ryoko; Hori, Takane; Hyodo, Mamoru; Ariyoshi, Keisuke</p> <p>2016-01-01</p> <p>We show possible scenarios for the occurrence of M ~ 7 interplate <span class="hlt">earthquakes</span> prior to and following the M ~ 9 <span class="hlt">earthquake</span> along the Japan Trench, such as the 2011 Tohoku-Oki <span class="hlt">earthquake</span>. One such M ~ 7 <span class="hlt">earthquake</span> is so-called the Miyagi-ken-Oki <span class="hlt">earthquake</span>, for which we conducted numerical simulations of <span class="hlt">earthquake</span> generation cycles by using realistic three-dimensional (3D) geometry of the subducting Pacific Plate. In a number of scenarios, the time interval between the M ~ 9 <span class="hlt">earthquake</span> and the subsequent Miyagi-ken-Oki <span class="hlt">earthquake</span> was equal to or shorter than the average <span class="hlt">recurrence</span> interval during the later stage of the M ~ 9 <span class="hlt">earthquake</span> cycle. The scenarios successfully reproduced important characteristics such as the <span class="hlt">recurrence</span> of M ~ 7 <span class="hlt">earthquakes</span>, coseismic slip distribution, afterslip distribution, the largest foreshock, and the largest aftershock of the 2011 <span class="hlt">earthquake</span>. Thus, these results suggest that we should prepare for future M ~ 7 <span class="hlt">earthquakes</span> in the Miyagi-ken-Oki segment even though this segment recently experienced large coseismic slip in 2011. PMID:27161897</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PNAS..114.4893W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PNAS..114.4893W"><span>Reading a 400,000-year record of <span class="hlt">earthquake</span> frequency for an intraplate fault</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, Randolph T.; Goodwin, Laurel B.; Sharp, Warren D.; Mozley, Peter S.</p> <p>2017-05-01</p> <p>Our understanding of the frequency of large <span class="hlt">earthquakes</span> at timescales longer than instrumental and historical records is based mostly on paleoseismic studies of fast-moving plate-boundary faults. Similar study of intraplate faults has been limited until now, because intraplate <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals are generally long (10s to 100s of thousands of years) relative to conventional paleoseismic records determined by trenching. Long-term variations in the <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals of intraplate faults therefore are poorly understood. Longer paleoseismic records for intraplate faults are required both to better quantify their <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals and to test competing models of <span class="hlt">earthquake</span> frequency (e.g., time-dependent, time-independent, and clustered). We present the results of U-Th dating of calcite veins in the Loma Blanca normal fault zone, Rio Grande rift, New Mexico, United States, that constrain <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals over much of the past ˜550 ka—the longest direct record of seismic frequency documented for any fault to date. The 13 distinct seismic events delineated by this effort demonstrate that for >400 ka, the Loma Blanca fault produced periodic large <span class="hlt">earthquakes</span>, consistent with a time-dependent model of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. However, this time-dependent series was interrupted by a cluster of <span class="hlt">earthquakes</span> at ˜430 ka. The carbon isotope composition of calcite formed during this seismic cluster records rapid degassing of CO2, suggesting an interval of anomalous fluid source. In concert with U-Th dates recording decreased <span class="hlt">recurrence</span> intervals, we infer seismicity during this interval records fault-valve behavior. These data provide insight into the long-term seismic behavior of the Loma Blanca fault and, by inference, other intraplate faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70020550','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70020550"><span>Absence of <span class="hlt">earthquake</span> correlation with Earth tides: An indication of high preseismic fault stress <span class="hlt">rate</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Vidale, J.E.; Agnew, D.C.; Johnston, M.J.S.; Oppenheimer, D.H.</p> <p>1998-01-01</p> <p>Because the <span class="hlt">rate</span> of stress change from the Earth tides exceeds that from tectonic stress accumulation, tidal triggering of <span class="hlt">earthquakes</span> would be expected if the final hours of loading of the fault were at the tectonic <span class="hlt">rate</span> and if rupture began soon after the achievement of a critical stress level. We analyze the tidal stresses and stress <span class="hlt">rates</span> on the fault planes and at the times of 13,042 <span class="hlt">earthquakes</span> which are so close to the San Andreas and Calaveras faults in California that we may take the fault plane to be known. We find that the stresses and stress <span class="hlt">rates</span> from Earth tides at the times of <span class="hlt">earthquakes</span> are distributed in the same way as tidal stresses and stress <span class="hlt">rates</span> at random times. While the <span class="hlt">rate</span> of <span class="hlt">earthquakes</span> when the tidal stress promotes failure is 2% higher than when the stress does not, this difference in <span class="hlt">rate</span> is not statistically significant. This lack of tidal triggering implies that preseismic stress <span class="hlt">rates</span> in the nucleation zones of <span class="hlt">earthquakes</span> are at least 0.15 bar/h just preceding seismic failure, much above the long-term tectonic stress <span class="hlt">rate</span> of 10-4 bar/h.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.733..232A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.733..232A"><span><span class="hlt">Earthquake</span> cycle simulations with <span class="hlt">rate</span>-and-state friction and power-law viscoelasticity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allison, Kali L.; Dunham, Eric M.</p> <p>2018-05-01</p> <p>We simulate <span class="hlt">earthquake</span> cycles with <span class="hlt">rate</span>-and-state fault friction and off-fault power-law viscoelasticity for the classic 2D antiplane shear problem of a vertical, strike-slip plate boundary fault. We investigate the interaction between fault slip and bulk viscous flow with experimentally-based flow laws for quartz-diorite and olivine for the crust and mantle, respectively. Simulations using three linear geotherms (dT/dz = 20, 25, and 30 K/km) produce different deformation styles at depth, ranging from significant interseismic fault creep to purely bulk viscous flow. However, they have almost identical <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> interval, nucleation depth, and down-dip coseismic slip limit. Despite these similarities, variations in the predicted surface deformation might permit discrimination of the deformation mechanism using geodetic observations. Additionally, in the 25 and 30 K/km simulations, the crust drags the mantle; the 20 K/km simulation also predicts this, except within 10 km of the fault where the reverse occurs. However, basal tractions play a minor role in the overall force balance of the lithosphere, at least for the flow laws used in our study. Therefore, the depth-integrated stress on the fault is balanced primarily by shear stress on vertical, fault-parallel planes. Because strain <span class="hlt">rates</span> are higher directly below the fault than far from it, stresses are also higher. Thus, the upper crust far from the fault bears a substantial part of the tectonic load, resulting in unrealistically high stresses. In the real Earth, this might lead to distributed plastic deformation or formation of subparallel faults. Alternatively, fault pore pressures in excess of hydrostatic and/or weakening mechanisms such as grain size reduction and thermo-mechanical coupling could lower the strength of the ductile fault root in the lower crust and, concomitantly, off-fault upper crustal stresses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.S11B2240A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S11B2240A"><span>The August 2011 Virginia and Colorado <span class="hlt">Earthquake</span> Sequences: Does Stress Drop Depend on Strain <span class="hlt">Rate</span>?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abercrombie, R. E.; Viegas, G.</p> <p>2011-12-01</p> <p>Our preliminary analysis of the August 2011 Virginia <span class="hlt">earthquake</span> sequence finds the <span class="hlt">earthquakes</span> to have high stress drops, similar to those of recent <span class="hlt">earthquakes</span> in NE USA, while those of the August 2011 Trinidad, Colorado, <span class="hlt">earthquakes</span> are moderate - in between those typical of interplate (California) and the east coast. These <span class="hlt">earthquakes</span> provide an unprecedented opportunity to study such source differences in detail, and hence improve our estimates of seismic hazard. Previously, the lack of well-recorded <span class="hlt">earthquakes</span> in the eastern USA severely limited our resolution of the source processes and hence the expected ground accelerations. Our preliminary findings are consistent with the idea that <span class="hlt">earthquake</span> faults strengthen during longer <span class="hlt">recurrence</span> times and intraplate faults fail at higher stress (and produce higher ground accelerations) than their interplate counterparts. We use the empirical Green's function (EGF) method to calculate source parameters for the Virginia mainshock and three larger aftershocks, and for the Trinidad mainshock and two larger foreshocks using IRIS-available stations. We select time windows around the direct P and S waves at the closest stations and calculate spectral ratios and source time functions using the multi-taper spectral approach (eg. Viegas et al., JGR 2010). Our preliminary results show that the Virginia sequence has high stress drops (~100-200 MPa, using Madariaga (1976) model), and the Colorado sequence has moderate stress drops (~20 MPa). These numbers are consistent with previous work in the regions, for example the Au Sable Forks (2002) <span class="hlt">earthquake</span>, and the 2010 Germantown (MD) <span class="hlt">earthquake</span>. We also calculate the radiated seismic energy and find the energy/moment ratio to be high for the Virginia <span class="hlt">earthquakes</span>, and moderate for the Colorado sequence. We observe no evidence of a breakdown in constant stress drop scaling in this limited number of <span class="hlt">earthquakes</span>. We extend our analysis to a larger number of <span class="hlt">earthquakes</span> and stations</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li class="active"><span>6</span></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_6 --> <div id="page_7" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="121"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1437/b/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1437/b/"><span><span class="hlt">Recurrence</span> Interval and Event Age Data for Type A Faults</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dawson, Timothy E.; Weldon, Ray J.; Biasi, Glenn P.</p> <p>2008-01-01</p> <p>This appendix summarizes available <span class="hlt">recurrence</span> interval, event age, and timing of most recent event data for Type A faults considered in the <span class="hlt">Earthquake</span> <span class="hlt">Rate</span> Model 2 (ERM 2) and used in the ERM 2 Appendix C analysis as well as Appendix N (time-dependent probabilities). These data have been compiled into an Excel workbook named Appendix B A-fault event ages_<span class="hlt">recurrence</span>_V5.0 (herein referred to as the Appendix B workbook). For convenience, the Appendix B workbook is attached to the end of this document as a series of tables. The tables within the Appendix B workbook include site locations, event ages, and <span class="hlt">recurrence</span> data, and in some cases, the interval of time between <span class="hlt">earthquakes</span> is also reported. The Appendix B workbook is organized as individual worksheets, with each worksheet named by fault and paleoseismic site. Each worksheet contains the site location in latitude and longitude, as well as information on event ages, and a summary of <span class="hlt">recurrence</span> data. Because the data has been compiled from different sources with different presentation styles, descriptions of the contents of each worksheet within the Appendix B spreadsheet are summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70170867','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70170867"><span>Likelihood testing of seismicity-based <span class="hlt">rate</span> forecasts of induced <span class="hlt">earthquakes</span> in Oklahoma and Kansas</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Moschetti, Morgan P.; Hoover, Susan M.; Mueller, Charles</p> <p>2016-01-01</p> <p>Likelihood testing of induced <span class="hlt">earthquakes</span> in Oklahoma and Kansas has identified the parameters that optimize the forecasting ability of smoothed seismicity models and quantified the recent temporal stability of the spatial seismicity patterns. Use of the most recent 1-year period of <span class="hlt">earthquake</span> data and use of 10–20-km smoothing distances produced the greatest likelihood. The likelihood that the locations of January–June 2015 <span class="hlt">earthquakes</span> were consistent with optimized forecasts decayed with increasing elapsed time between the catalogs used for model development and testing. Likelihood tests with two additional sets of <span class="hlt">earthquakes</span> from 2014 exhibit a strong sensitivity of the <span class="hlt">rate</span> of decay to the smoothing distance. Marked reductions in likelihood are caused by the nonstationarity of the induced <span class="hlt">earthquake</span> locations. Our results indicate a multiple-fold benefit from smoothed seismicity models in developing short-term <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecasts for induced <span class="hlt">earthquakes</span> in Oklahoma and Kansas, relative to the use of seismic source zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28413911','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28413911"><span><span class="hlt">Recurrence</span> <span class="hlt">rate</span> after thoracoscopic surgery for primary spontaneous pneumothorax.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dagnegård, Hanna H; Rosén, Alice; Sartipy, Ulrik; Bergman, Per</p> <p>2017-08-01</p> <p>There is an on-going discussion regarding the <span class="hlt">recurrence</span> <span class="hlt">rate</span> after surgery for primary spontaneous pneumothorax by video assisted thoracic surgery (VATS) or by thoracotomy access. This study aimed to describe the <span class="hlt">recurrence</span> <span class="hlt">rate</span>, and to identify a possible learning curve, following surgery for primary spontaneous pneumothorax by VATS. All patients who underwent surgery for primary spontaneous pneumothorax by VATS at Karolinska University Hospital 2004-2013 were reviewed. Preoperative and operative characteristics were obtained from medical records. Patients were followed-up through telephone interviews or questionnaires and by review of medical records. The primary outcome of interest was time to <span class="hlt">recurrence</span> of pneumothorax requiring intervention. Outcomes were compared between patients operated during 2004-June 2010 and July 2010-2013. 219 patients who underwent 234 consecutive procedures were included. The mean follow-up times were 6.3 and 2.9 years in the early and late period, respectively. The postoperative <span class="hlt">recurrence</span> <span class="hlt">rate</span> in the early period was 16% (11%-25%), 18% (12%-27%), and 18% (12%-27%), at 1, 3 and 5 years, compared to 1.7% (0.4%-6.8%), 7.6% (3.7%-15%), and 9.8% (4.8%-19%) at 1, 3 and 5 years, in the late period (p = 0.016). We found that the <span class="hlt">recurrence</span> <span class="hlt">rate</span> after thoracoscopic surgery for primary spontaneous pneumothorax decreased significantly during the study period. Our results strongly suggest that thoracoscopic surgery for pneumothorax involve a substantial learning curve.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16361306','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16361306"><span>Phenotype at diagnosis predicts <span class="hlt">recurrence</span> <span class="hlt">rates</span> in Crohn's disease.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wolters, F L; Russel, M G; Sijbrandij, J; Ambergen, T; Odes, S; Riis, L; Langholz, E; Politi, P; Qasim, A; Koutroubakis, I; Tsianos, E; Vermeire, S; Freitas, J; van Zeijl, G; Hoie, O; Bernklev, T; Beltrami, M; Rodriguez, D; Stockbrügger, R W; Moum, B</p> <p>2006-08-01</p> <p>In Crohn's disease (CD), studies associating phenotype at diagnosis and subsequent disease activity are important for patient counselling and health care planning. To calculate disease <span class="hlt">recurrence</span> <span class="hlt">rates</span> and to correlate these with phenotypic traits at diagnosis. A prospectively assembled uniformly diagnosed European population based inception cohort of CD patients was classified according to the Vienna classification for disease phenotype at diagnosis. Surgical and non-surgical <span class="hlt">recurrence</span> <span class="hlt">rates</span> throughout a 10 year follow up period were calculated. Multivariate analysis was performed to classify risk factors present at diagnosis for <span class="hlt">recurrent</span> disease. A total of 358 were classified for phenotype at diagnosis, of whom 262 (73.2%) had a first <span class="hlt">recurrence</span> and 113 patients (31.6%) a first surgical <span class="hlt">recurrence</span> during the first 10 years after diagnosis. Patients with upper gastrointestinal disease at diagnosis had an excess risk of <span class="hlt">recurrence</span> (hazard ratio 1.54 (95% confidence interval (CI) 1.13-2.10)) whereas age >/=40 years at diagnosis was protective (hazard ratio 0.82 (95% CI 0.70-0.97)). Colonic disease was a protective characteristic for resective surgery (hazard ratio 0.38 (95% CI 0.21-0.69)). More frequent resective surgical <span class="hlt">recurrences</span> were reported from Copenhagen (hazard ratio 3.23 (95% CI 1.32-7.89)). A mild course of disease in terms of disease <span class="hlt">recurrence</span> was observed in this European cohort. Phenotype at diagnosis had predictive value for disease <span class="hlt">recurrence</span> with upper gastrointestinal disease being the most important positive predictor. A phenotypic North-South gradient in CD may be present, illustrated by higher surgery risks in some of the Northern European centres.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T43D3039C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T43D3039C"><span>Repeating <span class="hlt">Earthquakes</span> Following an Mw 4.4 <span class="hlt">Earthquake</span> Near Luther, Oklahoma</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clements, T.; Keranen, K. M.; Savage, H. M.</p> <p>2015-12-01</p> <p>An Mw 4.4 <span class="hlt">earthquake</span> on April 16, 2013 near Luther, OK was one of the earliest M4+ <span class="hlt">earthquakes</span> in central Oklahoma, following the Prague sequence in 2011. A network of four local broadband seismometers deployed within a day of the Mw 4.4 event, along with six Oklahoma netquake stations, recorded more than 500 aftershocks in the two weeks following the Luther <span class="hlt">earthquake</span>. Here we use HypoDD (Waldhauser & Ellsworth, 2000) and waveform cross-correlation to obtain precise aftershock locations. The location uncertainty, calculated using the SVD method in HypoDD, is ~15 m horizontally and ~ 35 m vertically. The <span class="hlt">earthquakes</span> define a near vertical, NE-SW striking fault plane. Events occur at depths from 2 km to 3.5 km within the granitic basement, with a small fraction of events shallower, near the sediment-basement interface. <span class="hlt">Earthquakes</span> occur within a zone of ~200 meters thickness on either side of the best-fitting fault surface. We use an equivalency class algorithm to identity clusters of repeating events, defined as event pairs with median three-component correlation > 0.97 across common stations (Aster & Scott, 1993). Repeating events occur as doublets of only two events in over 50% of cases; overall, 41% of <span class="hlt">earthquakes</span> recorded occur as repeating events. The <span class="hlt">recurrence</span> intervals for the repeating events range from minutes to days, with common <span class="hlt">recurrence</span> intervals of less than two minutes. While clusters occur in tight dimensions, commonly of 80 m x 200 m, aftershocks occur in 3 distinct ~2km x 2km-sized patches along the fault. Our analysis suggests that with rapidly deployed local arrays, the plethora of ~Mw 4 <span class="hlt">earthquakes</span> occurring in Oklahoma and Southern Kansas can be used to investigate the <span class="hlt">earthquake</span> rupture process and the role of damage zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS13D..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS13D..03B"><span>Holocene Mass Transport Deposits in Western Norwegian fjords and lakes revealing prehistoric <span class="hlt">earthquake</span> history of Scandinavia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bellwald, B.; Hjelstuen, B. O.; Sejrup, H. P.; Kuvås, J.; Stokowy, T.</p> <p>2016-12-01</p> <p>The sensitivity of fjord sediments to seismic shaking makes fjord systems appropriate study sites when extending regional <span class="hlt">earthquake</span> catalogs back in time and when estimating <span class="hlt">recurrence</span> <span class="hlt">rates</span> of prehistoric <span class="hlt">earthquakes</span> in intraplate settings. In this study we compiled evidence of 140 postglacial mass movement events and their associated mass transport deposits (MTDs) from previously analyzed and new sediment cores and high-resolution seismic profiles from 22 fjord systems and six lakes in Western Norway. Evaluation of trigger mechanisms make us infer that most of these mass movement events were initiated by regional <span class="hlt">earthquakes</span>, and that both climate-related processes and tsunamis most likely can be excluded as trigger mechanism for most of the events. A total of 33 individual <span class="hlt">earthquakes</span> has been identified, which most likely outbalance the historically recorded events in magnitude, thus indicating magnitudes >6. Frequency plots of MTDs suggest high seismic activity in the early Holocene (11000-9700 cal. yrs BP), followed by seismic quiescence in the mid-Holocene before a seismic reactivation took place at 4000 cal. yrs BP. Coevally-triggered MTDs at 8100 cal. yrs BP are identified in all the archives, and are correlating with the age of the offshore Storegga slide. We estimate <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span> of 1/80 years directly after the last deglaciation of Western Norway (12800-11600 ca. yrs BP), 1/200 years for the early Holocene and 1/300 years for the last 4000 years. Our compilation suggests that the mid-Holocene is characterized by low seismic activity, suggesting <span class="hlt">recurrence</span> <span class="hlt">rates</span> of 1/1300 years. Comparisons of the Western Norwegian dataset with paleoseimologic studies of other previously glaciated intraplate settings indicate that both Scandinavia and the Alps show similar trends as Western Norway, whereas Eastern Canada is not correlating with the paleoseismologic trend of this study, which could be explained by different deglaciation histories.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70020668','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70020668"><span>Paleoseismic investigations in the Santa Cruz mountains, California: Implications for <span class="hlt">recurrence</span> of large-magnitude <span class="hlt">earthquakes</span> on the San Andreas fault</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Schwartz, D.P.; Pantosti, D.; Okumura, K.; Powers, T.J.; Hamilton, J.C.</p> <p>1998-01-01</p> <p>Trenching, microgeomorphic mapping, and tree ring analysis provide information on timing of paleoearthquakes and behavior of the San Andreas fault in the Santa Cruz mountains. At the Grizzly Flat site alluvial units dated at 1640-1659 A.D., 1679-1894 A.D., 1668-1893 A.D., and the present ground surface are displaced by a single event. This was the 1906 surface rupture. Combined trench dates and tree ring analysis suggest that the penultimate event occurred in the mid-1600s, possibly in an interval as narrow as 1632-1659 A.D. There is no direct evidence in the trenches for the 1838 or 1865 <span class="hlt">earthquakes</span>, which have been proposed as occurring on this part of the fault zone. In a minimum time of about 340 years only one large surface faulting event (1906) occurred at Grizzly Flat, in contrast to previous <span class="hlt">recurrence</span> estimates of 95-110 years for the Santa Cruz mountains segment. Comparison with dates of the penultimate San Andreas <span class="hlt">earthquake</span> at sites north of San Francisco suggests that the San Andreas fault between Point Arena and the Santa Cruz mountains may have failed either as a sequence of closely timed <span class="hlt">earthquakes</span> on adjacent segments or as a single long rupture similar in length to the 1906 rupture around the mid-1600s. The 1906 coseismic geodetic slip and the late Holocene geologic slip <span class="hlt">rate</span> on the San Francisco peninsula and southward are about 50-70% and 70% of their values north of San Francisco, respectively. The slip gradient along the 1906 rupture section of the San Andreas reflects partitioning of plate boundary slip onto the San Gregorio, Sargent, and other faults south of the Golden Gate. If a mid-1600s event ruptured the same section of the fault that failed in 1906, it supports the concept that long strike-slip faults can contain master rupture segments that repeat in both length and slip distribution. Recognition of a persistent slip <span class="hlt">rate</span> gradient along the northern San Andreas fault and the concept of a master segment remove the requirement that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1856253','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1856253"><span>Phenotype at diagnosis predicts <span class="hlt">recurrence</span> <span class="hlt">rates</span> in Crohn's disease</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wolters, F L; Russel, M G; Sijbrandij, J; Ambergen, T; Odes, S; Riis, L; Langholz, E; Politi, P; Qasim, A; Koutroubakis, I; Tsianos, E; Vermeire, S; Freitas, J; van Zeijl, G; Hoie, O; Bernklev, T; Beltrami, M; Rodriguez, D; Stockbrügger, R W; Moum, B</p> <p>2006-01-01</p> <p>Background In Crohn's disease (CD), studies associating phenotype at diagnosis and subsequent disease activity are important for patient counselling and health care planning. Aims To calculate disease <span class="hlt">recurrence</span> <span class="hlt">rates</span> and to correlate these with phenotypic traits at diagnosis. Methods A prospectively assembled uniformly diagnosed European population based inception cohort of CD patients was classified according to the Vienna classification for disease phenotype at diagnosis. Surgical and non‐surgical <span class="hlt">recurrence</span> <span class="hlt">rates</span> throughout a 10 year follow up period were calculated. Multivariate analysis was performed to classify risk factors present at diagnosis for <span class="hlt">recurrent</span> disease. Results A total of 358 were classified for phenotype at diagnosis, of whom 262 (73.2%) had a first <span class="hlt">recurrence</span> and 113 patients (31.6%) a first surgical <span class="hlt">recurrence</span> during the first 10 years after diagnosis. Patients with upper gastrointestinal disease at diagnosis had an excess risk of <span class="hlt">recurrence</span> (hazard ratio 1.54 (95% confidence interval (CI) 1.13–2.10)) whereas age ⩾40 years at diagnosis was protective (hazard ratio 0.82 (95% CI 0.70–0.97)). Colonic disease was a protective characteristic for resective surgery (hazard ratio 0.38 (95% CI 0.21–0.69)). More frequent resective surgical <span class="hlt">recurrences</span> were reported from Copenhagen (hazard ratio 3.23 (95% CI 1.32–7.89)). Conclusions A mild course of disease in terms of disease <span class="hlt">recurrence</span> was observed in this European cohort. Phenotype at diagnosis had predictive value for disease <span class="hlt">recurrence</span> with upper gastrointestinal disease being the most important positive predictor. A phenotypic North‐South gradient in CD may be present, illustrated by higher surgery risks in some of the Northern European centres. PMID:16361306</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70017139','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70017139"><span><span class="hlt">Earthquake</span> nucleation on faults with <span class="hlt">rate</span>-and state-dependent strength</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dieterich, J.H.</p> <p>1992-01-01</p> <p>Dieterich, J.H., 1992. <span class="hlt">Earthquake</span> nucleation on faults with <span class="hlt">rate</span>- and state-dependent strength. In: T. Mikumo, K. Aki, M. Ohnaka, L.J. Ruff and P.K.P. Spudich (Editors), <span class="hlt">Earthquake</span> Source Physics and <span class="hlt">Earthquake</span> Precursors. Tectonophysics, 211: 115-134. Faults with <span class="hlt">rate</span>- and state-dependent constitutive properties reproduce a range of observed fault slip phenomena including spontaneous nucleation of slip instabilities at stresses above some critical stress level and recovery of strength following slip instability. Calculations with a plane-strain fault model with spatially varying properties demonstrate that accelerating slip precedes instability and becomes localized to a fault patch. The dimensions of the fault patch follow scaling relations for the minimum critical length for unstable fault slip. The critical length is a function of normal stress, loading conditions and constitutive parameters which include Dc, the characteristic slip distance. If slip starts on a patch that exceeds the critical size, the length of the rapidly accelerating zone tends to shrink to the characteristic size as the time of instability approaches. Solutions have been obtained for a uniform, fixed-patch model that are in good agreement with results from the plane-strain model. Over a wide range of conditions, above the steady-state stress, the logarithm of the time to instability linearly decreases as the initial stress increases. Because nucleation patch length and premonitory displacement are proportional to Dc, the moment of premonitory slip scales by D3c. The scaling of Dc is currently an open question. Unless Dc for <span class="hlt">earthquake</span> faults is significantly greater than that observed on laboratory faults, premonitory strain arising from the nucleation process for <span class="hlt">earthquakes</span> may by too small to detect using current observation methods. Excluding the possibility that Dc in the nucleation zone controls the magnitude of the subsequent <span class="hlt">earthquake</span>, then the source dimensions of the smallest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70190039','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70190039"><span>A long-term <span class="hlt">earthquake</span> <span class="hlt">rate</span> model for the central and eastern United States from smoothed seismicity</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Moschetti, Morgan P.</p> <p>2015-01-01</p> <p>I present a long-term <span class="hlt">earthquake</span> <span class="hlt">rate</span> model for the central and eastern United States from adaptive smoothed seismicity. By employing pseudoprospective likelihood testing (L-test), I examined the effects of fixed and adaptive smoothing methods and the effects of catalog duration and composition on the ability of the models to forecast the spatial distribution of recent <span class="hlt">earthquakes</span>. To stabilize the adaptive smoothing method for regions of low seismicity, I introduced minor modifications to the way that the adaptive smoothing distances are calculated. Across all smoothed seismicity models, the use of adaptive smoothing and the use of <span class="hlt">earthquakes</span> from the recent part of the catalog optimizes the likelihood for tests with M≥2.7 and M≥4.0 <span class="hlt">earthquake</span> catalogs. The smoothed seismicity models optimized by likelihood testing with M≥2.7 catalogs also produce the highest likelihood values for M≥4.0 likelihood testing, thus substantiating the hypothesis that the locations of moderate-size <span class="hlt">earthquakes</span> can be forecast by the locations of smaller <span class="hlt">earthquakes</span>. The likelihood test does not, however, maximize the fraction of <span class="hlt">earthquakes</span> that are better forecast than a seismicity <span class="hlt">rate</span> model with uniform <span class="hlt">rates</span> in all cells. In this regard, fixed smoothing models perform better than adaptive smoothing models. The preferred model of this study is the adaptive smoothed seismicity model, based on its ability to maximize the joint likelihood of predicting the locations of recent small-to-moderate-size <span class="hlt">earthquakes</span> across eastern North America. The preferred <span class="hlt">rate</span> model delineates 12 regions where the annual <span class="hlt">rate</span> of M≥5 <span class="hlt">earthquakes</span> exceeds 2×10−3. Although these seismic regions have been previously recognized, the preferred forecasts are more spatially concentrated than the <span class="hlt">rates</span> from fixed smoothed seismicity models, with <span class="hlt">rate</span> increases of up to a factor of 10 near clusters of high seismic activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S23E..04G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S23E..04G"><span>Simulation Based <span class="hlt">Earthquake</span> Forecasting with RSQSim</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gilchrist, J. J.; Jordan, T. H.; Dieterich, J. H.; Richards-Dinger, K. B.</p> <p>2016-12-01</p> <p>We are developing a physics-based forecasting model for <span class="hlt">earthquake</span> ruptures in California. We employ the 3D boundary element code RSQSim to generate synthetic catalogs with millions of events that span up to a million years. The simulations incorporate <span class="hlt">rate</span>-state fault constitutive properties in complex, fully interacting fault systems. The Unified California <span class="hlt">Earthquake</span> Rupture Forecast Version 3 (UCERF3) model and data sets are used for calibration of the catalogs and specification of fault geometry. Fault slip <span class="hlt">rates</span> match the UCERF3 geologic slip <span class="hlt">rates</span> and catalogs are tuned such that <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> matches the UCERF3 model. Utilizing the Blue Waters Supercomputer, we produce a suite of million-year catalogs to investigate the epistemic uncertainty in the physical parameters used in the simulations. In particular, values of the <span class="hlt">rate</span>- and state-friction parameters a and b, the initial shear and normal stress, as well as the <span class="hlt">earthquake</span> slip speed, are varied over several simulations. In addition to testing multiple models with homogeneous values of the physical parameters, the parameters a, b, and the normal stress are varied with depth as well as in heterogeneous patterns across the faults. Cross validation of UCERF3 and RSQSim is performed within the SCEC Collaboratory for Interseismic Simulation and Modeling (CISM) to determine the affect of the uncertainties in physical parameters observed in the field and measured in the lab, on the uncertainties in probabilistic forecasting. We are particularly interested in the short-term hazards of multi-event sequences due to complex faulting and multi-fault ruptures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.mapstore.utah.gov/uga46.html','USGSPUBS'); return false;" href="http://www.mapstore.utah.gov/uga46.html"><span>The history of late holocene surface-faulting <span class="hlt">earthquakes</span> on the central segments of the Wasatch fault zone, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Duross, Christopher; Personius, Stephen; Olig, Susan S; Crone, Anthony J.; Hylland, Michael D.; Lund, William R; Schwartz, David P.</p> <p>2017-01-01</p> <p>The Wasatch fault (WFZ)—Utah’s longest and most active normal fault—forms a prominent eastern boundary to the Basin and Range Province in northern Utah. To provide paleoseismic data for a Wasatch Front regional <span class="hlt">earthquake</span> forecast, we synthesized paleoseismic data to define the timing and displacements of late Holocene surface-faulting <span class="hlt">earthquakes</span> on the central five segments of the WFZ. Our analysis yields revised histories of large (M ~7) surface-faulting <span class="hlt">earthquakes</span> on the segments, as well as estimates of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> and vertical slip <span class="hlt">rate</span>. We constrain the timing of four to six <span class="hlt">earthquakes</span> on each of the central segments, which together yields a history of at least 24 surface-faulting <span class="hlt">earthquakes</span> since ~6 ka. Using <span class="hlt">earthquake</span> data for each segment, inter-event <span class="hlt">recurrence</span> intervals range from about 0.6 to 2.5 kyr, and have a mean of 1.2 kyr. Mean <span class="hlt">recurrence</span>, based on closed seismic intervals, is ~1.1–1.3 kyr per segment, and when combined with mean vertical displacements per segment of 1.7–2.6 m, yield mean vertical slip <span class="hlt">rates</span> of 1.3–2.0 mm/yr per segment. These data refine the late Holocene behavior of the central WFZ; however, a significant source of uncertainty is whether structural complexities that define the segments of the WFZ act as hard barriers to ruptures propagating along the fault. Thus, we evaluate fault rupture models including both single-segment and multi-segment ruptures, and define 3–17-km-wide spatial uncertainties in the segment boundaries. These alternative rupture models and segment-boundary zones honor the WFZ paleoseismic data, take into account the spatial and temporal limitations of paleoseismic data, and allow for complex ruptures such as partial-segment and spillover ruptures. Our data and analyses improve our understanding of the complexities in normal-faulting <span class="hlt">earthquake</span> behavior and provide geological inputs for regional <span class="hlt">earthquake</span>-probability and seismic hazard assessments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70016367','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70016367"><span>The Wasatch fault zone, utah-segmentation and history of Holocene <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Machette, M.N.; Personius, S.F.; Nelson, A.R.; Schwartz, D.P.; Lund, W.R.</p> <p>1991-01-01</p> <p>The Wasatch fault zone (WFZ) forms the eastern boundary of the Basin and Range province and is the longest continuous, active normal fault (343 km) in the United States. It underlies an urban corridor of 1.6 million people (80% of Utah's population) representing the largest <span class="hlt">earthquake</span> risk in the interior of the western United States. We have used paleoseismological data to identify 10 discrete segments of the WFZ. Five are active, medial segments with Holocene slip <span class="hlt">rates</span> of 1-2 mm a-1, <span class="hlt">recurrence</span> intervals of 2000-4000 years and average lengths of about 50 km. Five are less active, distal segments with mostly pre-Holocene surface ruptures, late Quaternary slip <span class="hlt">rates</span> of 6.5 have occurred since 1860. Although the time scale of the clustering is different-130 years vs 1100 years-we consider the central Nevada-eastern California Seismic Belt to be a historic analog for movement on the WFZ during the past 1500 years. We have found no evidence that surface-rupturing events occurred on the WFZ during the past 400 years, a time period which is twice the average intracluster <span class="hlt">recurrence</span> interval and equal to the average Holocene <span class="hlt">recurrence</span> interval. In particular, the Brigham City segment (the northernmost medial segment) has not ruptured in the past 3600 years-a period that is about three times longer than this segment's average <span class="hlt">recurrence</span> interval during the early and middle Holocene. Although the WFZ's seismological record is one of relative quiescence, a comparison with other historic surface-rupturing <span class="hlt">earthquakes</span> in the region suggests that <span class="hlt">earthquakes</span> having moment magnitudes of 7.1-7.4 (or surface-wave magnitudes of 7.5-7.7)-each associated with tens of kilometers of surface rupture and several meters of normal dip slip-have occurred about every four centuries during the Holocene and should be expected in the future. ?? 1991.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUSM.U51A..03G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUSM.U51A..03G"><span>Holocene turbidite and onshore paleoseismic record of great <span class="hlt">earthquakes</span> on the Cascadia Subduction Zone: relevance for the Sumatra 2004 Great <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gutierrez-Pastor, J.; Nelson, C. H.; Goldfinger, C.; Johnson, J.</p> <p>2005-05-01</p> <p>Marine turbidite stratigraphy, onshore paleoseismic records of tsunami sand beds and co-seismic subsidence (Atwater and Hemphill-Haley, 1997; Kelsey et al., 2002; Witter et al., 2003) and tsunami sands of Japan (Satake et al., 1996) all show evidence for great <span class="hlt">earthquakes</span> (M ~ 9) on the Cascadia Subduction Zone. When a great <span class="hlt">earthquake</span> shakes 1000 kilometers of the Cascadia margin, sediment failures occur in all tributary canyons and resulting turbidity currents travel down the canyon systems and deposit synchronous turbidites in abyssal seafloor channels. These turbidite records provide a deepwater paleoseismic record of great <span class="hlt">earthquakes</span>. An onshore paleoseismic record develops from rapid coseismic subsidence resulting in buried marshes and drowned forests, and subsequent tsunami sand layer deposition. The Cascadia Basin provides the longest paleoseismic record of great <span class="hlt">earthquakes</span> that is presently available for a subduction zone. A total of 17 synchronous turbidites have deposited along ~700 km of the Cascadia margin during the Holocene time of ~10,000 cal yr. Because the youngest paleoseismic event in all turbidite and onshore records is 300 AD, the average <span class="hlt">recurrence</span> interval of Great <span class="hlt">Earthquakes</span> is ~ 600 yr. At least 6 smaller events have also ruptured shorter margin segments. Linkage of the rupture length of these events comes from relative dating tools such as the "confluence test" of Adams (1990), radiocarbon ages of onshore and offshore events and physical property correlation of individual event "signatures". We use both 14C ages and analysis of hemipelagic sediment thickness between turbidites (H), where H/sedimentation <span class="hlt">rate</span> = time between turbidite events to develop two <span class="hlt">recurrence</span> histories. Utilizing the most reliable 14C and hemipelagic data sets from turbidites for the past ~ 5000 yr, the minimum <span class="hlt">recurrence</span> time is ~ 300 yr and maximum time is ~ 1300 yr. There also is a <span class="hlt">recurrence</span> pattern through the entire Holocene that consists of a long time</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoJI.198.1159H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoJI.198.1159H"><span>A smoothed stochastic <span class="hlt">earthquake</span> <span class="hlt">rate</span> model considering seismicity and fault moment release for Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hiemer, S.; Woessner, J.; Basili, R.; Danciu, L.; Giardini, D.; Wiemer, S.</p> <p>2014-08-01</p> <p>We present a time-independent gridded <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecast for the European region including Turkey. The spatial component of our model is based on kernel density estimation techniques, which we applied to both past <span class="hlt">earthquake</span> locations and fault moment release on mapped crustal faults and subduction zone interfaces with assigned slip <span class="hlt">rates</span>. Our forecast relies on the assumption that the locations of past seismicity is a good guide to future seismicity, and that future large-magnitude events occur more likely in the vicinity of known faults. We show that the optimal weighted sum of the corresponding two spatial densities depends on the magnitude range considered. The kernel bandwidths and density weighting function are optimized using retrospective likelihood-based forecast experiments. We computed <span class="hlt">earthquake</span> activity <span class="hlt">rates</span> (a- and b-value) of the truncated Gutenberg-Richter distribution separately for crustal and subduction seismicity based on a maximum likelihood approach that considers the spatial and temporal completeness history of the catalogue. The final annual <span class="hlt">rate</span> of our forecast is purely driven by the maximum likelihood fit of activity <span class="hlt">rates</span> to the catalogue data, whereas its spatial component incorporates contributions from both <span class="hlt">earthquake</span> and fault moment-<span class="hlt">rate</span> densities. Our model constitutes one branch of the <span class="hlt">earthquake</span> source model logic tree of the 2013 European seismic hazard model released by the EU-FP7 project `Seismic HAzard haRmonization in Europe' (SHARE) and contributes to the assessment of epistemic uncertainties in <span class="hlt">earthquake</span> activity <span class="hlt">rates</span>. We performed retrospective and pseudo-prospective likelihood consistency tests to underline the reliability of our model and SHARE's area source model (ASM) using the testing algorithms applied in the collaboratory for the study of <span class="hlt">earthquake</span> predictability (CSEP). We comparatively tested our model's forecasting skill against the ASM and find a statistically significant better performance for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRB..119.4448C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRB..119.4448C"><span>Interseismic coupling, seismic potential, and <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> on the southern front of the Eastern Alps (NE Italy)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cheloni, D.; D'Agostino, N.; Selvaggi, G.</p> <p>2014-05-01</p> <p>Here we use continuous GPS observations to document the geodetic strain accumulation across the South-Eastern Alps (NE Italy). We estimate the interseismic coupling on the intracontinental collision thrust fault and discuss the seismic potential and <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. We invert the GPS velocities using the back slip approach to simultaneously estimate the relative angular velocity and the degree of interseismic coupling on the thrust fault that separates the Eastern Alps and the Venetian-Friulian plain. Comparison between the rigid rotation predicted motion and the shortening observed across the area indicates that the South-Eastern Alpine thrust front absorbs about 70% of the total convergence between the Adria and Eurasia plates. The coupling is computed on a north dipping fault following the continuous external seismogenic thrust front of the South-Eastern Alps. The modeled thrust fault is currently locked from the surface to a depth of ≈10 km. The transition zone between locked and creeping portions of the fault roughly corresponds with the belt of microseismicity parallel and to the north of the mountain front. The estimated moment deficit <span class="hlt">rate</span> is 1.3 ± 0.4 × 1017 Nm/yr. The comparison between the estimated moment deficit and that released historically by the <span class="hlt">earthquakes</span> suggests that to account for the moment deficit the following two factors or their combination should be considered: (1) a significant part of the observed interseismic coupling is released aseismically and (2) infrequent "large" events with long return period (> 1000 years) and with magnitudes larger than the value assigned to the largest historical events (Mw≈ 6.7).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70023365','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70023365"><span>Seismic hazard in Hawaii: High <span class="hlt">rate</span> of large <span class="hlt">earthquakes</span> and probabilistics ground-motion maps</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Klein, F.W.; Frankel, A.D.; Mueller, C.S.; Wesson, R.L.; Okubo, P.G.</p> <p>2001-01-01</p> <p>The seismic hazard and <span class="hlt">earthquake</span> occurrence <span class="hlt">rates</span> in Hawaii are locally as high as that near the most hazardous faults elsewhere in the United States. We have generated maps of peak ground acceleration (PGA) and spectral acceleration (SA) (at 0.2, 0.3 and 1.0 sec, 5% critical damping) at 2% and 10% exceedance probabilities in 50 years. The highest hazard is on the south side of Hawaii Island, as indicated by the MI 7.0, MS 7.2, and MI 7.9 <span class="hlt">earthquakes</span>, which occurred there since 1868. Probabilistic values of horizontal PGA (2% in 50 years) on Hawaii's south coast exceed 1.75g. Because some large <span class="hlt">earthquake</span> aftershock zones and the geometry of flank blocks slipping on subhorizontal decollement faults are known, we use a combination of spatially uniform sources in active flank blocks and smoothed seismicity in other areas to model seismicity. <span class="hlt">Rates</span> of <span class="hlt">earthquakes</span> are derived from magnitude distributions of the modem (1959-1997) catalog of the Hawaiian Volcano Observatory's seismic network supplemented by the historic (1868-1959) catalog. Modern magnitudes are ML measured on a Wood-Anderson seismograph or MS. Historic magnitudes may add ML measured on a Milne-Shaw or Bosch-Omori seismograph or MI derived from calibrated areas of MM intensities. Active flank areas, which by far account for the highest hazard, are characterized by distributions with b slopes of about 1.0 below M 5.0 and about 0.6 above M 5.0. The kinked distribution means that large <span class="hlt">earthquake</span> <span class="hlt">rates</span> would be grossly under-estimated by extrapolating small <span class="hlt">earthquake</span> <span class="hlt">rates</span>, and that longer catalogs are essential for estimating or verifying the <span class="hlt">rates</span> of large <span class="hlt">earthquakes</span>. Flank <span class="hlt">earthquakes</span> thus follow a semicharacteristic model, which is a combination of background seismicity and an excess number of large <span class="hlt">earthquakes</span>. Flank <span class="hlt">earthquakes</span> are geometrically confined to rupture zones on the volcano flanks by barriers such as rift zones and the seaward edge of the volcano, which may be expressed by a magnitude</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S21C..03L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S21C..03L"><span><span class="hlt">Earthquake</span> <span class="hlt">Rate</span> Models for Evolving Induced Seismicity Hazard in the Central and Eastern US</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Llenos, A. L.; Ellsworth, W. L.; Michael, A. J.</p> <p>2015-12-01</p> <p>Injection-induced <span class="hlt">earthquake</span> <span class="hlt">rates</span> can vary rapidly in space and time, which presents significant challenges to traditional probabilistic seismic hazard assessment methodologies that are based on a time-independent model of mainshock occurrence. To help society cope with rapidly evolving seismicity, the USGS is developing one-year hazard models for areas of induced seismicity in the central and eastern US to forecast the shaking due to all <span class="hlt">earthquakes</span>, including aftershocks which are generally omitted from hazards assessments (Petersen et al., 2015). However, the spatial and temporal variability of the <span class="hlt">earthquake</span> <span class="hlt">rates</span> make them difficult to forecast even on time-scales as short as one year. An initial approach is to use the previous year's seismicity <span class="hlt">rate</span> to forecast the next year's seismicity <span class="hlt">rate</span>. However, in places such as northern Oklahoma the <span class="hlt">rates</span> vary so rapidly over time that a simple linear extrapolation does not accurately forecast the future, even when the variability in the <span class="hlt">rates</span> is modeled with simulations based on an Epidemic-Type Aftershock Sequence (ETAS) model (Ogata, JASA, 1988) to account for <span class="hlt">earthquake</span> clustering. Instead of relying on a fixed time period for <span class="hlt">rate</span> estimation, we explore another way to determine when the <span class="hlt">earthquake</span> <span class="hlt">rate</span> should be updated. This approach could also objectively identify new areas where the induced seismicity hazard model should be applied. We will estimate the background seismicity <span class="hlt">rate</span> by optimizing a single set of ETAS aftershock triggering parameters across the most active induced seismicity zones -- Oklahoma, Guy-Greenbrier, the Raton Basin, and the Azle-Dallas-Fort Worth area -- with individual background <span class="hlt">rate</span> parameters in each zone. The full seismicity <span class="hlt">rate</span>, with uncertainties, can then be estimated using ETAS simulations and changes in <span class="hlt">rate</span> can be detected by applying change point analysis in ETAS transformed time with methods already developed for Poisson processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26095284','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26095284"><span>Clinical Perineal Streptococcal Infection in Children: Epidemiologic Features, Low Symptomatic <span class="hlt">Recurrence</span> <span class="hlt">Rate</span> after Treatment, and Risk Factors for <span class="hlt">Recurrence</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Clegg, Herbert William; Giftos, Peter Michael; Anderson, William Edward; Kaplan, Edward Lawrence; Johnson, Dwight Richard</p> <p>2015-09-01</p> <p>To evaluate the epidemiology of perineal streptococcal infection and <span class="hlt">recurrence</span> <span class="hlt">rates</span> following amoxicillin treatment. We used laboratory logs in a single pediatric practice to identify patients 0-18 years of age with perineal cultures positive for group A Streptococcus (GAS) and reviewed their medical charts. We described epidemiologic features, determined <span class="hlt">recurrence</span> <span class="hlt">rates</span> following antibiotic treatment, and performed a case-control study to identify possible risk factors for <span class="hlt">recurrence</span> in patients treated with amoxicillin. We found a perineal streptococcal infection <span class="hlt">rate</span> of 4.6 per 10,000 patient encounters and a <span class="hlt">recurrence</span> <span class="hlt">rate</span> in 157 patients with perineal streptococcal infection of 12.4% after amoxicillin. In male patients, the predominant site of involvement was the perianal region (86%), and for female patients, the perivaginal area (62%). Nearly 80% of patients were 2-7 years of age (range 18 days-12.5 years). Perineal streptococcal infection and GAS pharyngitis followed a similar seasonal pattern of occurrence with 65% of perineal streptococcal infection occurring October through March. In patients with perineal streptococcal infection, 95% had a concomitant pharyngeal culture positive for GAS. Best predictive factors for <span class="hlt">recurrence</span> after amoxicillin were longer duration of symptoms prior to diagnosis and having a sibling with perineal streptococcal infection at some time before or after the initial episode. Following treatment with amoxicillin, we found a low <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 12.4%. Amoxicillin can be expected to be reliable first-line therapy for perineal streptococcal infection. Copyright © 2015 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.T13C2619I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.T13C2619I"><span>Statistical analysis of seismicity <span class="hlt">rate</span> change in the Tokyo Metropolitan area due to the 2011 Tohoku <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ishibe, T.; Sakai, S.; Shimazaki, K.; Satake, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.</p> <p>2012-12-01</p> <p>We examined a relationship between the Coulomb Failure Function (ΔCFF) due to the Tohoku <span class="hlt">earthquake</span> (March 11, 2011; MJMA 9.0) and the seismicity <span class="hlt">rate</span> change in Tokyo Metropolitan area following March 2011. Because of large variation in focal mechanism in the Kanto region, the receiver faults for the ΔCFF were assumed to be two nodal planes of small (M ≥ 2.0) <span class="hlt">earthquakes</span> which occurred before and after the Tohoku <span class="hlt">earthquake</span>. The seismicity <span class="hlt">rate</span> changes, particularly the <span class="hlt">rate</span> increase, are well explained by ΔCFF due to the gigantic thrusting, while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration) may also contribute the <span class="hlt">rate</span> changes. Among 30,746 previous events provided by the National Research Institute for Earth Science and Disaster Prevention (M ≥ 2.0, July 1979 - July 2003), we used as receiver faults, almost 16,000 events indicate significant increase in ΔCFF, while about 8,000 events show significant decrease. Positive ΔCFF predicts seismicity <span class="hlt">rate</span> increase in southwestern Ibaraki and northern Chiba prefectures where intermediate-depth <span class="hlt">earthquakes</span> occur, and in shallow crust of the Izu-Oshima and Hakone regions. In these regions, seismicity <span class="hlt">rates</span> significantly increased after the Tohoku <span class="hlt">earthquake</span>. The seismicity has increased since March 2011 with respect to the Epidemic Type of Aftershock Sequence (ETAS) model (Ogata, 1988), indicating that the <span class="hlt">rate</span> change was due to the stress increase by the Tohoku <span class="hlt">earthquake</span>. The activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased <span class="hlt">rate</span> of seismicity in the southwestern Ibaraki and northern Chiba prefectures is still continuing. We also calculated ΔCFF due to the 2011 Tohoku <span class="hlt">earthquake</span> for the focal mechanism solutions of <span class="hlt">earthquakes</span> between April 2008 and October 2011 recorded on the Metropolitan Seismic Observation network (MeSO-net). The ΔCFF values for the <span class="hlt">earthquakes</span> after March 2011 show more</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li class="active"><span>7</span></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_7 --> <div id="page_8" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="141"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70025332','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70025332"><span>Late Holocene <span class="hlt">earthquakes</span> on the Toe Jam Hill fault, Seattle fault zone, Bainbridge Island, Washington</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, A.R.; Johnson, S.Y.; Kelsey, H.M.; Wells, R.E.; Sherrod, B.L.; Pezzopane, S.K.; Bradley, L.A.; Koehler, R. D.; Bucknam, R.C.</p> <p>2003-01-01</p> <p>Five trenches across a Holocene fault scarp yield the first radiocarbon-measured <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals for a crustal fault in western Washington. The scarp, the first to be revealed by laser imagery, marks the Toe Jam Hill fault, a north-dipping backthrust to the Seattle fault. Folded and faulted strata, liquefaction features, and forest soil A horizons buried by hanging-wall-collapse colluvium record three, or possibly four, <span class="hlt">earthquakes</span> between 2500 and 1000 yr ago. The most recent <span class="hlt">earthquake</span> is probably the 1050-1020 cal. (calibrated) yr B.P. (A.D. 900-930) <span class="hlt">earthquake</span> that raised marine terraces and triggered a tsunami in Puget Sound. Vertical deformation estimated from stratigraphic and surface offsets at trench sites suggests late Holocene <span class="hlt">earthquake</span> magnitudes near M7, corresponding to surface ruptures >36 km long. Deformation features recording poorly understood latest Pleistocene <span class="hlt">earthquakes</span> suggest that they were smaller than late Holocene <span class="hlt">earthquakes</span>. Postglacial <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals based on 97 radiocarbon ages, most on detrital charcoal, range from ???12,000 yr to as little as a century or less; corresponding fault-slip <span class="hlt">rates</span> are 0.2 mm/yr for the past 16,000 yr and 2 mm/yr for the past 2500 yr. Because the Toe Jam Hill fault is a backthrust to the Seattle fault, it may not have ruptured during every <span class="hlt">earthquake</span> on the Seattle fault. But the <span class="hlt">earthquake</span> history of the Toe Jam Hill fault is at least a partial proxy for the history of the rest of the Seattle fault zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17.1857C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17.1857C"><span>Methodology for <span class="hlt">earthquake</span> rupture <span class="hlt">rate</span> estimates of fault networks: example for the western Corinth rift, Greece</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chartier, Thomas; Scotti, Oona; Lyon-Caen, Hélène; Boiselet, Aurélien</p> <p>2017-10-01</p> <p>Modeling the seismic potential of active faults is a fundamental step of probabilistic seismic hazard assessment (PSHA). An accurate estimation of the <span class="hlt">rate</span> of <span class="hlt">earthquakes</span> on the faults is necessary in order to obtain the probability of exceedance of a given ground motion. Most PSHA studies consider faults as independent structures and neglect the possibility of multiple faults or fault segments rupturing simultaneously (fault-to-fault, FtF, ruptures). The Uniform California <span class="hlt">Earthquake</span> Rupture Forecast version 3 (UCERF-3) model takes into account this possibility by considering a system-level approach rather than an individual-fault-level approach using the geological, seismological and geodetical information to invert the <span class="hlt">earthquake</span> <span class="hlt">rates</span>. In many places of the world seismological and geodetical information along fault networks is often not well constrained. There is therefore a need to propose a methodology relying on geological information alone to compute <span class="hlt">earthquake</span> <span class="hlt">rates</span> of the faults in the network. In the proposed methodology, a simple distance criteria is used to define FtF ruptures and consider single faults or FtF ruptures as an aleatory uncertainty, similarly to UCERF-3. <span class="hlt">Rates</span> of <span class="hlt">earthquakes</span> on faults are then computed following two constraints: the magnitude frequency distribution (MFD) of <span class="hlt">earthquakes</span> in the fault system as a whole must follow an a priori chosen shape and the <span class="hlt">rate</span> of <span class="hlt">earthquakes</span> on each fault is determined by the specific slip <span class="hlt">rate</span> of each segment depending on the possible FtF ruptures. The modeled <span class="hlt">earthquake</span> <span class="hlt">rates</span> are then compared to the available independent data (geodetical, seismological and paleoseismological data) in order to weight different hypothesis explored in a logic tree.The methodology is tested on the western Corinth rift (WCR), Greece, where recent advancements have been made in the understanding of the geological slip <span class="hlt">rates</span> of the complex network of normal faults which are accommodating the ˜ 15 mm yr-1 north</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70016934','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70016934"><span>Wasatch fault zone, Utah - segmentation and history of Holocene <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Machette, Michael N.; Personius, Stephen F.; Nelson, Alan R.; Schwartz, David P.; Lund, William R.</p> <p>1991-01-01</p> <p>The Wasatch fault zone (WFZ) forms the eastern boundary of the Basin and Range province and is the longest continuous, active normal fault (343 km) in the United States. It underlies an urban corridor of 1.6 million people (80% of Utah's population) representing the largest <span class="hlt">earthquake</span> risk in the interior of the western United States. The authors have used paleoseismological data to identify 10 discrete segments of the WFZ. Five are active, medial segments with Holocene slip <span class="hlt">rates</span> of 1-2 mm a-1, <span class="hlt">recurrence</span> intervals of 2000-4000 years and average lengths of about 50 km. Five are less active, distal segments with mostly pre-Holocene surface ruptures, late Quaternary slip <span class="hlt">rates</span> of <0.5 mm a-1, <span class="hlt">recurrence</span> intervals of ???10,000 years and average lengths of about 20 km. Surface-faulting events on each of the medial segments of the WFZ formed 2-4-m-high scarps repeatedly during the Holocene. Paleoseismological records for the past 6000 years indicate that a major surface-rupturing <span class="hlt">earthquake</span> has occurred along one of the medial segments about every 395 ?? 60 years. However, between about 400 and 1500 years ago, the WFZ experienced six major surface-rupturing events, an average of one event every 220 years, or about twice as often as expected from the 6000-year record. Evidence has been found that surface-rupturing events occurred on the WFZ during the past 400 years, a time period which is twice the average intracluster <span class="hlt">recurrence</span> interval and equal to the average Holocene <span class="hlt">recurrence</span> interval.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S21D..03N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S21D..03N"><span>Variability of <span class="hlt">recurrence</span> interval for New Zealand surface-rupturing paleoearthquakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nicol, A., , Prof; Robinson, R., Jr.; Van Dissen, R. J.; Harvison, A.</p> <p>2015-12-01</p> <p><span class="hlt">Recurrence</span> interval (RI) for successive <span class="hlt">earthquakes</span> on individual faults is recorded by paleoseismic datasets for surface-rupturing <span class="hlt">earthquakes</span> which, in New Zealand, have magnitudes of >Mw ~6 to 7.2 depending on the thickness of the brittle crust. New Zealand faults examined have mean RI of ~130 to 8500 yrs, with an upper bound censored by the sample duration (<30 kyr) and an inverse relationship to fault slip <span class="hlt">rate</span>. Frequency histograms, probability density functions (PDFs) and coefficient of variation (CoV= standard deviation/arithmetic mean) values have been used to quantify RI variability for geological and simulated <span class="hlt">earthquakes</span> on >100 New Zealand active faults. RI for individual faults can vary by more than an order of magnitude. CoV of RI for paleoearthquake data comprising 4-10 events ranges from ~0.2 to 1 with a mean of 0.6±0.2. These values are generally comparable to simulated <span class="hlt">earthquakes</span> (>100 events per fault) and suggest that RI ranges from quasi periodic (e.g., ~0.2-0.5) to random (e.g., ~1.0). Comparison of <span class="hlt">earthquake</span> simulation and paleoearthquake data indicates that the mean and CoV of RI can be strongly influenced by sampling artefacts including; the magnitude of completeness, the dimensionality of spatial sampling and the duration of the sample period. Despite these sampling issues RI for the best of the geological data (i.e. >6 events) and <span class="hlt">earthquake</span> simulations are described by log-normal or Weibull distributions with long <span class="hlt">recurrence</span> tails (~3 times the mean) and provide a basis for quantifying real RI variability (rather than sampling artefacts). Our analysis indicates that CoV of RI is negatively related to fault slip <span class="hlt">rate</span>. These data are consistent with the notion that fault interaction and associated stress perturbations arising from slip on larger faults are more likely to advance or retard future slip on smaller faults than visa versa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.U33C..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.U33C..01R"><span>What Controls Subduction <span class="hlt">Earthquake</span> Size and Occurrence?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ruff, L. J.</p> <p>2008-12-01</p> <p>There is a long history of observational studies on the size and <span class="hlt">recurrence</span> intervals of the large underthrusting <span class="hlt">earthquakes</span> in subduction zones. In parallel with this documentation of the variability in both <span class="hlt">recurrence</span> times and <span class="hlt">earthquake</span> sizes -- both within and amongst subduction zones -- there have been numerous suggestions for what controls size and occurrence. In addition to the intrinsic scientific interest in these issues, there are direct applications to hazards mitigation. In this overview presentation, I review past progress, consider current paradigms, and look toward future studies that offer some resolution of long- standing questions. Given the definition of seismic moment, <span class="hlt">earthquake</span> size is the product of overall static stress drop, down-dip fault width, and along-strike fault length. The long-standing consensus viewpoint is that for the largest <span class="hlt">earthquakes</span> in a subduction zone: stress-drop is constant, fault width is the down-dip extent of the seismogenic portion of the plate boundary, but that along-strike fault length can vary from one large <span class="hlt">earthquake</span> to the next. While there may be semi-permanent segments along a subduction zone, successive large <span class="hlt">earthquakes</span> can rupture different combinations of segments. Many investigations emphasize the role of asperities within the segments, rather than segment edges. Thus, the question of <span class="hlt">earthquake</span> size is translated into: "What controls the along-strike segmentation, and what determines which segments will rupture in a particular <span class="hlt">earthquake</span> cycle?" There is no consensus response to these questions. Over the years, the suggestions for segmentation control include physical features in the subducted plate, physical features in the over-lying plate, and more obscure -- and possibly ever-changing -- properties of the plate interface such as the hydrologic conditions. It seems that the full global answer requires either some unforeseen breakthrough, or the long-term hard work of falsifying all candidate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19890328','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19890328"><span>Long aftershock sequences within continents and implications for <span class="hlt">earthquake</span> hazard assessment.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stein, Seth; Liu, Mian</p> <p>2009-11-05</p> <p>One of the most powerful features of plate tectonics is that the known plate motions give insight into both the locations and average <span class="hlt">recurrence</span> interval of future large <span class="hlt">earthquakes</span> on plate boundaries. Plate tectonics gives no insight, however, into where and when <span class="hlt">earthquakes</span> will occur within plates, because the interiors of ideal plates should not deform. As a result, within plate interiors, assessments of <span class="hlt">earthquake</span> hazards rely heavily on the assumption that the locations of small <span class="hlt">earthquakes</span> shown by the short historical record reflect continuing deformation that will cause future large <span class="hlt">earthquakes</span>. Here, however, we show that many of these recent <span class="hlt">earthquakes</span> are probably aftershocks of large <span class="hlt">earthquakes</span> that occurred hundreds of years ago. We present a simple model predicting that the length of aftershock sequences varies inversely with the <span class="hlt">rate</span> at which faults are loaded. Aftershock sequences within the slowly deforming continents are predicted to be significantly longer than the decade typically observed at rapidly loaded plate boundaries. These predictions are in accord with observations. So the common practice of treating continental <span class="hlt">earthquakes</span> as steady-state seismicity overestimates the hazard in presently active areas and underestimates it elsewhere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70029548','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70029548"><span>Time-dependent <span class="hlt">earthquake</span> probabilities</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gomberg, J.; Belardinelli, M.E.; Cocco, M.; Reasenberg, P.</p> <p>2005-01-01</p> <p>We have attempted to provide a careful examination of a class of approaches for estimating the conditional probability of failure of a single large <span class="hlt">earthquake</span>, particularly approaches that account for static stress perturbations to tectonic loading as in the approaches of Stein et al. (1997) and Hardebeck (2004). We have loading as in the framework based on a simple, generalized <span class="hlt">rate</span> change formulation and applied it to these two approaches to show how they relate to one another. We also have attempted to show the connection between models of seismicity <span class="hlt">rate</span> changes applied to (1) populations of independent faults as in background and aftershock seismicity and (2) changes in estimates of the conditional probability of failures of different members of a the notion of failure <span class="hlt">rate</span> corresponds to successive failures of different members of a population of faults. The latter application requires specification of some probability distribution (density function of PDF) that describes some population of potential <span class="hlt">recurrence</span> times. This PDF may reflect our imperfect knowledge of when past <span class="hlt">earthquakes</span> have occurred on a fault (epistemic uncertainty), the true natural variability in failure times, or some combination of both. We suggest two end-member conceptual single-fault models that may explain natural variability in <span class="hlt">recurrence</span> times and suggest how they might be distinguished observationally. When viewed deterministically, these single-fault patch models differ significantly in their physical attributes, and when faults are immature, they differ in their responses to stress perturbations. Estimates of conditional failure probabilities effectively integrate over a range of possible deterministic fault models, usually with ranges that correspond to mature faults. Thus conditional failure probability estimates usually should not differ significantly for these models. Copyright 2005 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.G34A..04D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.G34A..04D"><span><span class="hlt">Earthquake</span> Clustering in Noisy Viscoelastic Systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dicaprio, C. J.; Simons, M.; Williams, C. A.; Kenner, S. J.</p> <p>2006-12-01</p> <p>Geologic studies show evidence for temporal clustering of <span class="hlt">earthquakes</span> on certain fault systems. Since post- seismic deformation may result in a variable loading <span class="hlt">rate</span> on a fault throughout the inter-seismic period, it is reasonable to expect that the rheology of the non-seismogenic lower crust and mantle lithosphere may play a role in controlling <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> times. Previously, the role of rheology of the lithosphere on the seismic cycle had been studied with a one-dimensional spring-dashpot-slider model (Kenner and Simons [2005]). In this study we use the finite element code PyLith to construct a two-dimensional continuum model a strike-slip fault in an elastic medium overlying one or more linear Maxwell viscoelastic layers loaded in the far field by a constant velocity boundary condition. Taking advantage of the linear properties of the model, we use the finite element solution to one <span class="hlt">earthquake</span> as a spatio-temporal Green's function. Multiple Green's function solutions, scaled by the size of each <span class="hlt">earthquake</span>, are then summed to form an <span class="hlt">earthquake</span> sequence. When the shear stress on the fault reaches a predefined yield stress it is allowed to slip, relieving all accumulated shear stress. Random variation in the fault yield stress from one <span class="hlt">earthquake</span> to the next results in a temporally clustered <span class="hlt">earthquake</span> sequence. The amount of clustering depends on a non-dimensional number, W, called the Wallace number. For models with one viscoelastic layer, W is equal to the standard deviation of the <span class="hlt">earthquake</span> stress drop divided by the viscosity times the tectonic loading <span class="hlt">rate</span>. This definition of W is modified from the original one used in Kenner and Simons [2005] by using the standard deviation of the stress drop instead of the mean stress drop. We also use a new, more appropriate, metric to measure the amount of temporal clustering of the system. W is the ratio of the viscoelastic relaxation <span class="hlt">rate</span> of the system to the tectonic loading <span class="hlt">rate</span> of the system. For values of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17794569','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17794569"><span>The 1985 central chile <span class="hlt">earthquake</span>: a repeat of previous great <span class="hlt">earthquakes</span> in the region?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Comte, D; Eisenberg, A; Lorca, E; Pardo, M; Ponce, L; Saragoni, R; Singh, S K; Suárez, G</p> <p>1986-07-25</p> <p>A great <span class="hlt">earthquake</span> (surface-wave magnitude, 7.8) occurred along the coast of central Chile on 3 March 1985, causing heavy damage to coastal towns. Intense foreshock activity near the epicenter of the main shock occurred for 11 days before the <span class="hlt">earthquake</span>. The aftershocks of the 1985 <span class="hlt">earthquake</span> define a rupture area of 170 by 110 square kilometers. The <span class="hlt">earthquake</span> was forecast on the basis of the nearly constant repeat time (83 +/- 9 years) of great <span class="hlt">earthquakes</span> in this region. An analysis of previous <span class="hlt">earthquakes</span> suggests that the rupture lengths of great shocks in the region vary by a factor of about 3. The nearly constant repeat time and variable rupture lengths cannot be reconciled with time- or slip-predictable models of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. The great <span class="hlt">earthquakes</span> in the region seem to involve a variable rupture mode and yet, for unknown reasons, remain periodic. Historical data suggest that the region south of the 1985 rupture zone should now be considered a gap of high seismic potential that may rupture in a great <span class="hlt">earthquake</span> in the next few tens of years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T43B0689S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T43B0689S"><span>Dynamics of folding: Impact of fault bend folds on <span class="hlt">earthquake</span> cycles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sathiakumar, S.; Barbot, S.; Hubbard, J.</p> <p>2017-12-01</p> <p><span class="hlt">Earthquakes</span> in subduction zones and subaerial convergent margins are some of the largest in the world. So far, forecasts of future <span class="hlt">earthquakes</span> have primarily relied on assessing past <span class="hlt">earthquakes</span> to look for seismic gaps and slip deficits. However, the roles of fault geometry and off-fault plasticity are typically overlooked. We use structural geology (fault-bend folding theory) to inform fault modeling in order to better understand how deformation is accommodated on the geological time scale and through the <span class="hlt">earthquake</span> cycle. Fault bends in megathrusts, like those proposed for the Nepal Himalaya, will induce folding of the upper plate. This introduces changes in the slip <span class="hlt">rate</span> on different fault segments, and therefore on the loading <span class="hlt">rate</span> at the plate interface, profoundly affecting the pattern of <span class="hlt">earthquake</span> cycles. We develop numerical simulations of slip evolution under <span class="hlt">rate</span>-and-state friction and show that this effect introduces segmentation of the <span class="hlt">earthquake</span> cycle. In crustal dynamics, it is challenging to describe the dynamics of fault-bend folds, because the deformation is accommodated by small amounts of slip parallel to bedding planes ("flexural slip"), localized on axial surface, i.e. folding axes pinned to fault bends. We use dislocation theory to describe the dynamics of folding along these axial surfaces, using analytic solutions that provide displacement and stress kernels to simulate the temporal evolution of folding and assess the effects of folding on <span class="hlt">earthquake</span> cycles. Studies of the 2015 Gorkha <span class="hlt">earthquake</span>, Nepal, have shown that fault geometry can affect <span class="hlt">earthquake</span> segmentation. Here, we show that in addition to the fault geometry, the actual geology of the rocks in the hanging wall of the fault also affect critical parameters, including the loading <span class="hlt">rate</span> on parts of the fault, based on fault-bend folding theory. Because loading velocity controls the <span class="hlt">recurrence</span> time of <span class="hlt">earthquakes</span>, these two effects together are likely to have a strong impact on the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910315W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910315W"><span>Controls on the long term <span class="hlt">earthquake</span> behavior of an intraplate fault revealed by U-Th and stable isotope analyses of syntectonic calcite veins</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Williams, Randolph; Goodwin, Laurel; Sharp, Warren; Mozley, Peter</p> <p>2017-04-01</p> <p>U-Th dates on calcite precipitated in coseismic extension fractures in the Loma Blanca normal fault zone, Rio Grande rift, NM, USA, constrain <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals from 150-565 ka. This is the longest direct record of seismicity documented for a fault in any tectonic environment. Combined U-Th and stable isotope analyses of these calcite veins define 13 distinct <span class="hlt">earthquake</span> events. These data show that for more than 400 ka the Loma Blanca fault produced <span class="hlt">earthquakes</span> with a mean <span class="hlt">recurrence</span> interval of 40 ± 7 ka. The coefficient of variation for these events is 0.40, indicating strongly periodic seismicity consistent with a time-dependent model of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. Stochastic statistical analyses further validate the inference that <span class="hlt">earthquake</span> behavior on the Loma Blanca was time-dependent. The time-dependent nature of these <span class="hlt">earthquakes</span> suggests that the seismic cycle was fundamentally controlled by a stress renewal process. However, this periodic cycle was punctuated by an episode of clustered seismicity at 430 ka. <span class="hlt">Recurrence</span> intervals within the <span class="hlt">earthquake</span> cluster were as low as 5-11 ka. Breccia veins formed during this episode exhibit carbon isotope signatures consistent with having formed through pronounced degassing of a CO2 charged brine during post-failure, fault-localized fluid migration. The 40 ka periodicity of the long-term <span class="hlt">earthquake</span> record of the Loma Blanca fault is similar in magnitude to <span class="hlt">recurrence</span> intervals documented through paleoseismic studies of other normal faults in the Rio Grande rift and Basin and Range Province. We propose that it represents a background <span class="hlt">rate</span> of failure in intraplate extension. The short-term, clustered seismicity that occurred on the fault records an interruption of the stress renewal process, likely by elevated fluid pressure in deeper structural levels of the fault, consistent with fault-valve behavior. The relationship between <span class="hlt">recurrence</span> interval and inferred fluid degassing suggests that pore fluid pressure</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T13E..02V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T13E..02V"><span>Aseismic Slip Throughout the <span class="hlt">Earthquake</span> Cycle in Nicoya Peninsula, Costa Rica</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Voss, N. K.; Liu, Z.; Hobbs, T. E.; Schwartz, S. Y.; Malservisi, R.; Dixon, T. H.; Protti, M.</p> <p>2017-12-01</p> <p>Geodetically resolved Slow Slip Events (SSE), a large M7.6 <span class="hlt">earthquake</span>, and afterslip have all been documented in the last 16 years of observation in Nicoya, Costa Rica. We present a synthesis of the observations of observed aseismic slip behavior. SSEs in Nicoya are observed both during the late inter-seismic period and the post-seismic period, despite ongoing post-seismic phenomena. While <span class="hlt">recurrence</span> <span class="hlt">rates</span> appear unchanged by position within <span class="hlt">earthquake</span> cycle, SSE behavior does vary before and after the event. We discuss how afterslip may be responsible for this change in behavior. We also present observations of a pre-<span class="hlt">earthquake</span> transient observed starting 6 months prior to the M7.6 megathrust <span class="hlt">earthquake</span>. This <span class="hlt">earthquake</span> takes place within an asperity that is surrounded by regions which previously underwent slow slip behavior. We compare how this pre-<span class="hlt">earthquake</span> transient, modeled as aseismic slip, differs from observations of typical Nicoya SSEs. Finally, we attempt to explain the segmentation of behaviors in Costa Rica with a simple frictional model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70025174','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70025174"><span>Why <span class="hlt">earthquakes</span> correlate weakly with the solid Earth tides: Effects of periodic stress on the <span class="hlt">rate</span> and probability of <span class="hlt">earthquake</span> occurrence</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Beeler, N.M.; Lockner, D.A.</p> <p>2003-01-01</p> <p>We provide an explanation why <span class="hlt">earthquake</span> occurrence does not correlate well with the daily solid Earth tides. The explanation is derived from analysis of laboratory experiments in which faults are loaded to quasiperiodic failure by the combined action of a constant stressing <span class="hlt">rate</span>, intended to simulate tectonic loading, and a small sinusoidal stress, analogous to the Earth tides. Event populations whose failure times correlate with the oscillating stress show two modes of response; the response mode depends on the stressing frequency. Correlation that is consistent with stress threshold failure models, e.g., Coulomb failure, results when the period of stress oscillation exceeds a characteristic time tn; the degree of correlation between failure time and the phase of the driving stress depends on the amplitude and frequency of the stress oscillation and on the stressing <span class="hlt">rate</span>. When the period of the oscillating stress is less than tn, the correlation is not consistent with threshold failure models, and much higher stress amplitudes are required to induce detectable correlation with the oscillating stress. The physical interpretation of tn is the duration of failure nucleation. Behavior at the higher frequencies is consistent with a second-order dependence of the fault strength on sliding <span class="hlt">rate</span> which determines the duration of nucleation and damps the response to stress change at frequencies greater than 1/tn. Simple extrapolation of these results to the Earth suggests a very weak correlation of <span class="hlt">earthquakes</span> with the daily Earth tides, one that would require >13,000 <span class="hlt">earthquakes</span> to detect. On the basis of our experiments and analysis, the absence of definitive daily triggering of <span class="hlt">earthquakes</span> by the Earth tides requires that for <span class="hlt">earthquakes</span>, tn exceeds the daily tidal period. The experiments suggest that the minimum typical duration of <span class="hlt">earthquake</span> nucleation on the San Andreas fault system is ???1 year.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.H43C1466H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.H43C1466H"><span>Gradual decay of elevated landslide <span class="hlt">rates</span> after a large <span class="hlt">earthquake</span> in the Finisterre Mountains, Papua New Guinea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hovius, N.; Marc, O.</p> <p>2013-12-01</p> <p>Large <span class="hlt">earthquakes</span> can cause widespread mass wasting and landslide <span class="hlt">rates</span> can stay high after a seismic event. The <span class="hlt">rate</span> of decay of seismically enhanced mass wasting determines the total erosional effect of an <span class="hlt">earthquake</span>. It is also an important term in the post-seismic redevelopment of epicentral areas. Using a time series of Landsat images spanning 1990-2010, we have determined the evolution of landslide <span class="hlt">rates</span> in the western Finisterre Mountains, Papua New Guinea. There, two <span class="hlt">earthquakes</span> with Mw 6.7and 6.9 occurred at depth of about 20 km on the range-bounding Ramu-Markam fault in 1993. These <span class="hlt">earthquakes</span> triggered landslides with a total volume of about 0.15 km3. Landslide <span class="hlt">rates</span> were up to four orders of magnitude higher after the <span class="hlt">earthquakes</span> than in preceding years, decaying to background values over a period of 2-3 years. Due to this short decay time, seismically induced landslides added only 5% to the volume of co-seismic landslides. This contrasts with another well-documented example, the 1999 Chi-Chi <span class="hlt">earthquake</span> in Taiwan, where post-seismic landsliding may have increased the total eroded volume by a factor 3-5. In the Finisterre case, landslide <span class="hlt">rates</span> may have been slightly less than normal for up to a decade after the decay period, but this effect is partially obscured by the impact of a smaller <span class="hlt">earthquake</span> in 1997. Regardless, the <span class="hlt">rate</span> of decay of landslide incidence was unrelated to both the seismic moment release in aftershocks and local precipitation. A control on this decay <span class="hlt">rate</span> has not yet been identified.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26220125','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26220125"><span>High-powered microwave ablation of larger hepatocellular carcinoma: evaluation of <span class="hlt">recurrence</span> <span class="hlt">rate</span> and factors related to <span class="hlt">recurrence</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, N N; Lu, W; Cheng, X J; Liu, J Y; Zhou, Y H; Li, F</p> <p>2015-11-01</p> <p>To evaluate the safety and efficacy of high-powered (80-100 W) percutaneous microwave ablation (MWA) at a frequency of 2450±10 MHz for treating larger hepatocellular carcinoma (HCC) and to predict the risk factors of local <span class="hlt">recurrence</span> after high-powered MWA. The study was approved by the Institutional Review Board, and informed consent was waived because of the retrospective study design. Forty-five patients with a total of 60 lesions received high-power (80-100 W) MWA at a frequency of 2450±10 MHz through a percutaneous approach that was guided by ultrasound. Of the 60 lesions with a maximum tumour measuring 3-8 cm, 46 lesions were 3-5 cm and 14 were 5-8 cm. The complete ablation <span class="hlt">rates</span>, local <span class="hlt">recurrence</span> <span class="hlt">rates</span>, complications, and short-term survival were analysed. Ten possible risk factors for local <span class="hlt">recurrence</span> were analysed. The complete ablation <span class="hlt">rates</span> were 82.61% for the first ablation and 100% for the second ablation for 3-5 cm lesions. The complete ablation <span class="hlt">rates</span> were 64.29% (82.61% versus 64.29%, p=0.037) for the first ablation and 85.71% (100% versus 85.71%, p=0.055) for the second ablation for 5-8 cm lesions. Local <span class="hlt">recurrence</span> was observed in 11 out of the 45 (24.44%) successfully treated patients. The 1-year and 2-year survival <span class="hlt">rates</span> were 95.56% (43/45) and 86.67% (39/45), respectively. No procedure-related mortality was observed and no major bleeding, liver rupture, or liver abscesses occurred. Univariate analysis showed that a positive correlation existed between the number of lesions (p=0.022), proximity to the risk area (p=0.001), pre-ablation alpha-fetoprotein (AFP) levels (p=0.025), hepatitis B virus (HBV)-DNA replication (p=0.027) and local <span class="hlt">recurrence</span>. Multivariate analysis identified HBV-DNA (p=0.031) and proximity to the risk area (p=0.039) as the independent prognosis factors causing postoperative HCC local <span class="hlt">recurrence</span>. High-powered MWA of larger hepatocellular carcinomas appears to be a safe and effective treatment. HBV-DNA and proximity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S41C..04W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S41C..04W"><span>Long-term changes in regular and low-frequency <span class="hlt">earthquake</span> inter-event times near Parkfield, CA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, C.; Shelly, D. R.; Johnson, P. A.; Gomberg, J. S.; Peng, Z.</p> <p>2012-12-01</p> <p>The temporal evolution of <span class="hlt">earthquake</span> inter-event time may provide important clues for the timing of future events and underlying physical mechanisms of <span class="hlt">earthquake</span> nucleation. In this study, we examine inter-event times from 12-yr catalogs of ~50,000 <span class="hlt">earthquakes</span> and ~730,000 LFEs in the vicinity of the Parkfield section of the San Andreas Fault. We focus on the long-term evolution of inter-event times after the 2003 Mw6.5 San Simeon and 2004 Mw6.0 Parkfield <span class="hlt">earthquakes</span>. We find that inter-event times decrease by ~4 orders of magnitudes after the Parkfield and San Simeon <span class="hlt">earthquakes</span> and are followed by a long-term recovery with time scales of ~3 years and more than 8 years for <span class="hlt">earthquakes</span> along and to the southwest of the San Andreas fault, respectively. The differing long-term recovery of the <span class="hlt">earthquake</span> inter-event times is likely a manifestation of different aftershock recovery time scales that reflect the different tectonic loading <span class="hlt">rates</span> in the two regions. We also observe a possible decrease of LFE inter-event times in some LFE families, followed by a recovery with time scales of ~4 months to several years. The drop in the <span class="hlt">recurrence</span> time of LFE after the Parkfield <span class="hlt">earthquake</span> is likely caused by a combination of the dynamic and positive static stress induced by the Parkfield <span class="hlt">earthquake</span>, and the long-term recovery in LFE <span class="hlt">recurrence</span> time could be due to post-seismic relaxation or gradual recovery of the fault zone material properties. Our on-going work includes better constraining and understanding the physical mechanisms responsible for the observed long-term recovery in <span class="hlt">earthquake</span> and LFE inter-event times.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.S11B2241W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S11B2241W"><span>Comparing the stress change characteristics and aftershock decay <span class="hlt">rate</span> of the 2011 Mineral, VA, <span class="hlt">earthquake</span> with similar <span class="hlt">earthquakes</span> from a variety of tectonic settings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Walsh, L. S.; Montesi, L. G.; Sauber, J. M.; Watters, T. R.; Kim, W.; Martin, A. J.; Anderson, R.</p> <p>2011-12-01</p> <p>On August 23, 2011, the magnitude 5.8 Mineral, VA, <span class="hlt">earthquake</span> rocked the U.S. national capital region (Washington, DC) drawing worldwide attention to the occurrence of intraplate <span class="hlt">earthquakes</span>. Using regional Coulomb stress change, we evaluate to what extent slip on faults during the Mineral, VA, <span class="hlt">earthquake</span> and its aftershocks may have increased stress on notable Cenozoic fault systems in the DC metropolitan area: the central Virginia seismic zone, the DC fault zone, and the Stafford fault system. Our Coulomb stress maps indicate that the transfer of stress from the Mineral, VA, mainshock was at least 500 times greater than that produced from the magnitude 3.4 Germantown, MD, <span class="hlt">earthquake</span> that occurred northwest of DC on July 16, 2010. Overall, the Mineral, VA, <span class="hlt">earthquake</span> appears to have loaded faults of optimum orientation in the DC metropolitan region, bringing them closer to failure. The distribution of aftershocks of the Mineral, VA, <span class="hlt">earthquake</span> will be compared with Coulomb stress change maps. We further characterize the Mineral, VA, <span class="hlt">earthquake</span> by comparing its aftershock decay <span class="hlt">rate</span> with that of blind thrust <span class="hlt">earthquakes</span> with similar magnitude, focal mechanism, and depth from a variety of tectonic settings. In particular, we compare aftershock decay relations of the Mineral, VA, <span class="hlt">earthquake</span> with two well studied California reverse faulting events, the August 4, 1985 Kettleman Hills (Mw = 6.1) and October 1, 1987 Whittier Narrow (Mw = 5.9) <span class="hlt">earthquakes</span>. Through these relations we test the hypothesis that aftershock duration is inversely proportional to fault stressing <span class="hlt">rate</span>, suggesting that aftershocks in active tectonic margins may last only a few years while aftershocks in intraplate regions could endure for decades to a century.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.738..112K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.738..112K"><span>Temporal slip-<span class="hlt">rate</span> stability and variations on the Hope Fault, New Zealand, during the late Quaternary</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Khajavi, Narges; Nicol, Andrew; Quigley, Mark C.; Langridge, Robert M.</p> <p>2018-07-01</p> <p>The Hope Fault transfers slip from Hikurangi subduction to the Alpine Fault in the northern South Island of New Zealand. It accommodates mainly dextral strike slip and currently carries the highest slip <span class="hlt">rate</span> in the Marlborough Fault System. Displacements, displacement <span class="hlt">rates</span> and <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals have been determined using a combination of high resolution LiDAR for 59 dextral displacements ( 2.5-200 m) together with calibrated radiocarbon ages ( 130 yr to 13,000 yr) for abandoned stream channels, terrace risers and alluvial fans. Mean single-event displacement (SED) of 3 ± 0.6 m (2.2 to 4.6 m for 21 measurements) and mean <span class="hlt">recurrence</span> interval of 266 ± 100 yr (range 128 to 560 yr) have been determined for the five most recent surface-rupturing <span class="hlt">earthquakes</span>. On time scales ≥2300 yr the dextral slip <span class="hlt">rate</span> is uniform at 12.2 ± 2.4 mm/yr, however, when averaged over time intervals of 230 to 1700 yr slip <span class="hlt">rates</span> range from 4 to 46.4 mm/yr. This order-of-magnitude variability in slip <span class="hlt">rate</span> over shorter timescales cannot be fully attributed to errors in displacement and age data, and is at least partly due to variations in <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> interval and inferred SED. Short-term non-characteristic <span class="hlt">earthquake</span> behaviour may be due to changes in fault loading arising from stress interactions between different segments of the Hope Fault and nearby faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012NHESS..12.3191N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012NHESS..12.3191N"><span>Great <span class="hlt">earthquakes</span> along the Western United States continental margin: implications for hazards, stratigraphy and turbidite lithology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nelson, C. H.; Gutiérrez Pastor, J.; Goldfinger, C.; Escutia, C.</p> <p>2012-11-01</p> <p>We summarize the importance of great <span class="hlt">earthquakes</span> (Mw ≳ 8) for hazards, stratigraphy of basin floors, and turbidite lithology along the active tectonic continental margins of the Cascadia subduction zone and the northern San Andreas Transform Fault by utilizing studies of swath bathymetry visual core descriptions, grain size analysis, X-ray radiographs and physical properties. <span class="hlt">Recurrence</span> times of Holocene turbidites as proxies for <span class="hlt">earthquakes</span> on the Cascadia and northern California margins are analyzed using two methods: (1) radiometric dating (14C method), and (2) relative dating, using hemipelagic sediment thickness and sedimentation <span class="hlt">rates</span> (H method). The H method provides (1) the best estimate of minimum <span class="hlt">recurrence</span> times, which are the most important for seismic hazards risk analysis, and (2) the most complete dataset of <span class="hlt">recurrence</span> times, which shows a normal distribution pattern for paleoseismic turbidite frequencies. We observe that, on these tectonically active continental margins, during the sea-level highstand of Holocene time, triggering of turbidity currents is controlled dominantly by <span class="hlt">earthquakes</span>, and paleoseismic turbidites have an average <span class="hlt">recurrence</span> time of ~550 yr in northern Cascadia Basin and ~200 yr along northern California margin. The minimum <span class="hlt">recurrence</span> times for great <span class="hlt">earthquakes</span> are approximately 300 yr for the Cascadia subduction zone and 130 yr for the northern San Andreas Fault, which indicates both fault systems are in (Cascadia) or very close (San Andreas) to the early window for another great <span class="hlt">earthquake</span>. On active tectonic margins with great <span class="hlt">earthquakes</span>, the volumes of mass transport deposits (MTDs) are limited on basin floors along the margins. The maximum run-out distances of MTD sheets across abyssal-basin floors along active margins are an order of magnitude less (~100 km) than on passive margins (~1000 km). The great <span class="hlt">earthquakes</span> along the Cascadia and northern California margins cause seismic strengthening of the sediment, which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.2315C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.2315C"><span>Do submarine landslides and turbidites provide a faithful record of large magnitude <span class="hlt">earthquakes</span> in the Western Mediterranean?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clare, Michael</p> <p>2016-04-01</p> <p>Large <span class="hlt">earthquakes</span> and associated tsunamis pose a potential risk to coastal communities. <span class="hlt">Earthquakes</span> may trigger submarine landslides that mix with surrounding water to produce turbidity currents. Recent studies offshore Algeria have shown that <span class="hlt">earthquake</span>-triggered turbidity currents can break important communication cables. If large <span class="hlt">earthquakes</span> reliably trigger landslides and turbidity currents, then their deposits can be used as a long-term record to understand temporal trends in <span class="hlt">earthquake</span> activity. It is important to understand in which settings this approach can be applied. We provide some suggestions for future Mediterranean palaeoseismic studies, based on learnings from three sites. Two long piston cores from the Balearic Abyssal Plain provide long-term (<150 ka) records of large volume turbidites. The frequency distribution form of turbidite <span class="hlt">recurrence</span> indicates a constant hazard <span class="hlt">rate</span> through time and is similar to the Poisson distribution attributed to large <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> on a regional basis. Turbidite thickness varies in response to sea level, which is attributed to proximity and availability of sediment. While mean turbidite <span class="hlt">recurrence</span> is similar to the seismogenic El Asnam fault in Algeria, geochemical analysis reveals not all turbidites were sourced from the Algerian margin. The basin plain record is instead an amalgamation of flows from Algeria, Sardinia, and river fed systems further to the north, many of which were not <span class="hlt">earthquake</span>-triggered. Thus, such distal basin plain settings are not ideal sites for turbidite palaoeseimology. Boxcores from the eastern Algerian slope reveal a thin silty turbidite dated to ~700 ya. Given its similar appearance across a widespread area and correlative age, the turbidite is inferred to have been <span class="hlt">earthquake</span>-triggered. More recent <span class="hlt">earthquakes</span> that have affected the Algerian slope are not recorded, however. Unlike the central and western Algerian slopes, the eastern part lacks canyons and had limited sediment</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.2963N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.2963N"><span>Hydromechanical <span class="hlt">Earthquake</span> Nucleation Model Forecasts Onset, Peak, and Falling <span class="hlt">Rates</span> of Induced Seismicity in Oklahoma and Kansas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Norbeck, J. H.; Rubinstein, J. L.</p> <p>2018-04-01</p> <p>The <span class="hlt">earthquake</span> activity in Oklahoma and Kansas that began in 2008 reflects the most widespread instance of induced seismicity observed to date. We develop a reservoir model to calculate the hydrologic conditions associated with the activity of 902 saltwater disposal wells injecting into the Arbuckle aquifer. Estimates of basement fault stressing conditions inform a <span class="hlt">rate</span>-and-state friction <span class="hlt">earthquake</span> nucleation model to forecast the seismic response to injection. Our model replicates many salient features of the induced <span class="hlt">earthquake</span> sequence, including the onset of seismicity, the timing of the peak seismicity <span class="hlt">rate</span>, and the reduction in seismicity following decreased disposal activity. We present evidence for variable time lags between changes in injection and seismicity <span class="hlt">rates</span>, consistent with the prediction from <span class="hlt">rate</span>-and-state theory that seismicity <span class="hlt">rate</span> transients occur over timescales inversely proportional to stressing <span class="hlt">rate</span>. Given the efficacy of the hydromechanical model, as confirmed through a likelihood statistical test, the results of this study support broader integration of <span class="hlt">earthquake</span> physics within seismic hazard analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA....13211T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA....13211T"><span><span class="hlt">Earthquake</span> models using <span class="hlt">rate</span> and state friction and fast multipoles</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tullis, T.</p> <p>2003-04-01</p> <p>The most realistic current <span class="hlt">earthquake</span> models employ laboratory-derived non-linear constitutive laws. These are the <span class="hlt">rate</span> and state friction laws having both a non-linear viscous or direct effect and an evolution effect in which frictional resistance depends on time of stationary contact and has a memory of past slip velocity that fades with slip. The frictional resistance depends on the log of the slip velocity as well as the log of stationary hold time, and the fading memory involves an approximately exponential decay with slip. Due to the nonlinearly of these laws, analytical <span class="hlt">earthquake</span> models are not attainable and numerical models are needed. The situation is even more difficult if true dynamic models are sought that deal with inertial forces and slip velocities on the order of 1 m/s as are observed during dynamic <span class="hlt">earthquake</span> slip. Additional difficulties that exist if the dynamic slip phase of <span class="hlt">earthquakes</span> is modeled arise from two sources. First, many physical processes might operate during dynamic slip, but they are only poorly understood, the relative importance of the processes is unknown, and the processes are even more nonlinear than those described by the current <span class="hlt">rate</span> and state laws. Constitutive laws describing such behaviors are still being developed. Second, treatment of inertial forces and the influence that dynamic stresses from elastic waves may have on slip on the fault requires keeping track of the history of slip on remote parts of the fault as far into the past as it takes waves to travel from there. This places even more stringent requirements on computer time. Challenges for numerical modeling of complete <span class="hlt">earthquake</span> cycles are that both time steps and mesh sizes must be small. Time steps must be milliseconds during dynamic slip, and yet models must represent <span class="hlt">earthquake</span> cycles 100 years or more in length; methods using adaptive step sizes are essential. Element dimensions need to be on the order of meters, both to approximate continuum behavior</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.724...80V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.724...80V"><span><span class="hlt">Recurrent</span> slow slip events as a barrier to the northward rupture propagation of the 2016 Pedernales <span class="hlt">earthquake</span> (Central Ecuador)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vaca, Sandro; Vallée, Martin; Nocquet, Jean-Mathieu; Battaglia, Jean; Régnier, Marc</p> <p>2018-01-01</p> <p>The northern Ecuador segment of the Nazca/South America subduction zone shows spatially heterogeneous interseismic coupling. Two highly coupled zones (0.4° S-0.35° N and 0.8° N-4.0° N) are separated by a low coupled area, hereafter referred to as the Punta Galera-Mompiche Zone (PGMZ). Large interplate <span class="hlt">earthquakes</span> repeatedly occurred within the coupled zones in 1958 (Mw 7.7) and 1979 (Mw 8.1) for the northern patch and in 1942 (Mw 7.8) and 2016 (Mw 7.8) for the southern patch, while the whole segment is thought to have rupture during the 1906 Mw 8.4-8.8 great <span class="hlt">earthquake</span>. We find that during the last decade, the PGMZ has experienced regular and frequent seismic swarms. For the best documented sequence (December 2013-January 2014), a joint seismological and geodetic analysis reveals a six-week-long Slow Slip Event (SSE) associated with a seismic swarm. During this period, the microseismicity is organized into families of similar <span class="hlt">earthquakes</span> spatially and temporally correlated with the evolution of the aseismic slip. The moment release (3.4 × 1018 Nm, Mw 6.3), over a 60 × 40 km area, is considerably larger than the moment released by <span class="hlt">earthquakes</span> (5.8 × 1015 Nm, Mw 4.4) during the same time period. In 2007-2008, a similar seismic-aseismic episode occurred, with higher magnitudes both for the seismic and aseismic processes. Cross-correlation analyses of the seismic waveforms over a 15 years-long period further suggest a 2-year repeat time for seismic swarms, which also implies that SSEs <span class="hlt">recurrently</span> affect this area. Such SSEs contribute to release the accumulated stress, likely explaining why the 2016 Pedernales <span class="hlt">earthquake</span> did not propagate northward into the PGMZ.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.T42A..04N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.T42A..04N"><span>Tectonic controls on <span class="hlt">earthquake</span> size distribution and seismicity <span class="hlt">rate</span>: slab buoyancy and slab bending</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nishikawa, T.; Ide, S.</p> <p>2014-12-01</p> <p>There are clear variations in maximum <span class="hlt">earthquake</span> magnitude among Earth's subduction zones. These variations have been studied extensively and attributed to differences in tectonic properties in subduction zones, such as relative plate velocity and subducting plate age [Ruff and Kanamori, 1980]. In addition to maximum <span class="hlt">earthquake</span> magnitude, the seismicity of medium to large <span class="hlt">earthquakes</span> also differs among subduction zones, such as the b-value (i.e., the slope of the <span class="hlt">earthquake</span> size distribution) and the frequency of seismic events. However, the casual relationship between the seismicity of medium to large <span class="hlt">earthquakes</span> and subduction zone tectonics has been unclear. Here we divide Earth's subduction zones into over 100 study regions following Ide [2013] and estimate b-values and the background seismicity rate—the frequency of seismic events excluding aftershocks—for subduction zones worldwide using the maximum likelihood method [Utsu, 1965; Aki, 1965] and the epidemic type aftershock sequence (ETAS) model [Ogata, 1988]. We demonstrate that the b-value varies as a function of subducting plate age and trench depth, and that the background seismicity <span class="hlt">rate</span> is related to the degree of slab bending at the trench. Large <span class="hlt">earthquakes</span> tend to occur relatively frequently (lower b-values) in shallower subduction zones with younger slabs, and more <span class="hlt">earthquakes</span> occur in subduction zones with deeper trench and steeper dip angle. These results suggest that slab buoyancy, which depends on subducting plate age, controls the <span class="hlt">earthquake</span> size distribution, and that intra-slab faults due to slab bending, which increase with the steepness of the slab dip angle, have influence on the frequency of seismic events, because they produce heterogeneity in plate coupling and efficiently inject fluid to elevate pore fluid pressure on the plate interface. This study reveals tectonic factors that control <span class="hlt">earthquake</span> size distribution and seismicity <span class="hlt">rate</span>, and these relationships between seismicity and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S33A2749D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S33A2749D"><span>Reactivity of seismicity <span class="hlt">rate</span> to static Coulomb stress changes of two consecutive large <span class="hlt">earthquakes</span> in the central Philippines</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dianala, J. D. B.; Aurelio, M.; Rimando, J. M.; Taguibao, K.</p> <p>2015-12-01</p> <p>In a region with little understanding in terms of active faults and seismicity, two large-magnitude reverse-fault related <span class="hlt">earthquakes</span> occurred within 100km of each other in separate islands of the Central Philippines—the Mw=6.7 February 2012 Negros <span class="hlt">earthquake</span> and the Mw=7.2 October 2013 Bohol <span class="hlt">earthquake</span>. Based on source faults that were defined using onshore, offshore seismic reflection, and seismicity data, stress transfer models for both <span class="hlt">earthquakes</span> were calculated using the software Coulomb. Coulomb stress triggering between the two main shocks is unlikely as the stress change caused by Negros <span class="hlt">earthquake</span> on the Bohol fault was -0.03 bars. Correlating the stress changes on optimally-oriented reverse faults with seismicity <span class="hlt">rate</span> changes shows that areas that decreased both in static stress and seismicity <span class="hlt">rate</span> after the first <span class="hlt">earthquake</span> were then areas with increased static stress and increased seismicity <span class="hlt">rate</span> caused by the second <span class="hlt">earthquake</span>. These areas with now increased stress, especially those with seismicity showing reactivity to static stress changes caused by the two <span class="hlt">earthquakes</span>, indicate the presence of active structures in the island of Cebu. Comparing the history of instrumentally recorded seismicity and the recent large <span class="hlt">earthquakes</span> of Negros and Bohol, these structures in Cebu have the potential to generate large <span class="hlt">earthquakes</span>. Given that the Philippines' second largest metropolitan area (Metro Cebu) is in close proximity, detailed analysis of the <span class="hlt">earthquake</span> potential and seismic hazards in these areas should be undertaken.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910909C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910909C"><span>Seismic hazard assessment over time: Modelling <span class="hlt">earthquakes</span> in Taiwan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chan, Chung-Han; Wang, Yu; Wang, Yu-Ju; Lee, Ya-Ting</p> <p>2017-04-01</p> <p>To assess the seismic hazard with temporal change in Taiwan, we develop a new approach, combining both the Brownian Passage Time (BPT) model and the Coulomb stress change, and implement the seismogenic source parameters by the Taiwan <span class="hlt">Earthquake</span> Model (TEM). The BPT model was adopted to describe the rupture <span class="hlt">recurrence</span> intervals of the specific fault sources, together with the time elapsed since the last fault-rupture to derive their long-term rupture probability. We also evaluate the short-term seismicity <span class="hlt">rate</span> change based on the static Coulomb stress interaction between seismogenic sources. By considering above time-dependent factors, our new combined model suggests an increased long-term seismic hazard in the vicinity of active faults along the western Coastal Plain and the Longitudinal Valley, where active faults have short <span class="hlt">recurrence</span> intervals and long elapsed time since their last ruptures, and/or short-term elevated hazard levels right after the occurrence of large <span class="hlt">earthquakes</span> due to the stress triggering effect. The stress enhanced by the February 6th, 2016, Meinong ML 6.6 <span class="hlt">earthquake</span> also significantly increased rupture probabilities of several neighbouring seismogenic sources in Southwestern Taiwan and raised hazard level in the near future. Our approach draws on the advantage of incorporating long- and short-term models, to provide time-dependent <span class="hlt">earthquake</span> probability constraints. Our time-dependent model considers more detailed information than any other published models. It thus offers decision-makers and public officials an adequate basis for rapid evaluations of and response to future emergency scenarios such as victim relocation and sheltering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.734..148S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.734..148S"><span>Limit on slip <span class="hlt">rate</span> and timing of recent seismic ground-ruptures on the Jinghong fault, SE of the eastern Himalayan syntaxis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, Xuhua; Weldon, Ray; Liu-Zeng, Jing; Wang, Yu; Weldon, Elise; Sieh, Kerry; Li, Zhigang; Zhang, Jinyu; Yao, Wenqian; Li, Zhanfei</p> <p>2018-06-01</p> <p>Quantifying slip <span class="hlt">rates</span> and <span class="hlt">earthquake</span> occurrence of active faults on the Shan Plateau, southeast of the eastern Himalayan syntaxis, is critical to assessing the seismic hazard and understanding the kinematics and geodynamics of this region. Most previous estimates of slip <span class="hlt">rates</span> are averaged over either many millions of years using offset geological markers or decades using GPS. Well-constrained millennial slip <span class="hlt">rates</span> of these faults remain sparse and constraints on <span class="hlt">recurrence</span> <span class="hlt">rates</span> of damaging <span class="hlt">earthquakes</span> exist only for a few faults. Here we investigate the millennial slip <span class="hlt">rate</span> and timing of recent <span class="hlt">earthquakes</span> on the Jinghong fault, one of the geomorphically most significant sinistral-slip faults on the central Shan Plateau. We map and reconstruct fault offset (18 ± 5 m) of alluvial fan features at Manpa on the central Jinghong fault, using a 0.1 m-resolution digital surface model obtained from an unmanned aerial vehicle survey. We establish a slip <span class="hlt">rate</span>, ≤2.5 ± 0.7 mm/yr over the past 7000 years, using pit-exposed stratigraphy. This millennial slip <span class="hlt">rate</span> is consistent with <span class="hlt">rates</span> averaged over both decadal and million-year timescales. Excavations at three sites near the town of Gelanghe on the northeastern Jinghong fault demonstrate 1) that the last seismic ground-rupture occurred between 482 and 889 cal yr BP, most likely in the narrower window 824-767 cal yr BP, if the lack of large <span class="hlt">earthquakes</span> in the historical <span class="hlt">earthquake</span> record is reliable, and 2) that multiple fault ruptures have occurred since 3618 cal yr BP. Combining this finding with a lack of large <span class="hlt">earthquakes</span> in the 800-year-long Chinese historic record in this region, we suggest an average <span class="hlt">recurrence</span> interval of seismic ground-ruptures on the order of 1000 years. This <span class="hlt">recurrence</span> interval is consistent with the slip <span class="hlt">rate</span> of the Jinghong fault and the size and <span class="hlt">earthquake</span> frequency on other sinistral faults on the Shan Plateau.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1437/d/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1437/d/"><span><span class="hlt">Earthquake</span> <span class="hlt">Rate</span> Model 2 of the 2007 Working Group for California <span class="hlt">Earthquake</span> Probabilities, Magnitude-Area Relationships</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stein, Ross S.</p> <p>2008-01-01</p> <p>The Working Group for California <span class="hlt">Earthquake</span> Probabilities must transform fault lengths and their slip <span class="hlt">rates</span> into <span class="hlt">earthquake</span> moment-magnitudes. First, the down-dip coseismic fault dimension, W, must be inferred. We have chosen the Nazareth and Hauksson (2004) method, which uses the depth above which 99% of the background seismicity occurs to assign W. The product of the observed or inferred fault length, L, with the down-dip dimension, W, gives the fault area, A. We must then use a scaling relation to relate A to moment-magnitude, Mw. We assigned equal weight to the Ellsworth B (Working Group on California <span class="hlt">Earthquake</span> Probabilities, 2003) and Hanks and Bakun (2007) equations. The former uses a single logarithmic relation fitted to the M=6.5 portion of data of Wells and Coppersmith (1994); the latter uses a bilinear relation with a slope change at M=6.65 (A=537 km2) and also was tested against a greatly expanded dataset for large continental transform <span class="hlt">earthquakes</span>. We also present an alternative power law relation, which fits the newly expanded Hanks and Bakun (2007) data best, and captures the change in slope that Hanks and Bakun attribute to a transition from area- to length-scaling of <span class="hlt">earthquake</span> slip. We have not opted to use the alternative relation for the current model. The selections and weights were developed by unanimous consensus of the Executive Committee of the Working Group, following an open meeting of scientists, a solicitation of outside opinions from additional scientists, and presentation of our approach to the Scientific Review Panel. The magnitude-area relations and their assigned weights are unchanged from that used in Working Group (2003).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20804358','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20804358"><span>The method of treatment cessation and <span class="hlt">recurrence</span> <span class="hlt">rate</span> of amblyopia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Walsh, Leah A; Hahn, Erik K; LaRoche, G Robert</p> <p>2009-09-01</p> <p>To date, much of the research regarding amblyopia has been focused on which therapeutic modality is the most efficacious in amblyopia management. Unfortunately, there is a lack of research into which method of treatment cessation is the most appropriate once therapy has been completed. The purpose of this study is to investigate if the cessation method affects the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of amblyopia. This study was a prospective randomized clinical trial of 20 subjects who were wearing full-time occlusion and were at the end point of their therapy. The subjects were randomized into one of two groups: abrupt cessation or therapy tapering. All subjects were followed for 3 consecutive 4-week intervals, for a total of 12 weeks, to assess the short-term <span class="hlt">recurrence</span> <span class="hlt">rate</span> of amblyopia. Subjects who were in the tapered group had their occlusion reduced from full-time occlusion (all waking hours minus one) to 50% of waking hours at study enrollment (i.e., from 12 hours/day to 6 hours per day); occlusion was reduced by an additional 50% at the first 4-week study visit (i.e., from 6 hours/day to 3 hours), with occlusion being discontinued completely at the week 8 visit. All subjects who were in the abrupt cessation group had their full-time occlusion discontinued completely at the start of the study (i.e., from 12 hours/day to none). Additional assessments were also conducted at week 26 and week 52 post-therapy cessation to determine the longer term amblyopia regression <span class="hlt">rate</span>. For the purposes of this study, <span class="hlt">recurrence</span> was defined as a 0.2 (10 letters) or more logarithm of the minimum angle of resolution (logMAR) loss of visual acuity. A <span class="hlt">recurrence</span> of amblyopia occurred in 4 of 17 (24%; CI 9%-47%) participants completing the study by the week 52 study end point. There were 2 subjects from each treatment group who demonstrated a study protocol-defined <span class="hlt">recurrence</span>. There was a 24% risk of amblyopia <span class="hlt">recurrence</span> if therapy was discontinued abruptly or tapered in 8 weeks. In this small</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189611','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189611"><span><span class="hlt">Earthquake</span> geology of the Bulnay Fault (Mongolia)</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Rizza, Magali; Ritz, Jean-Franciois; Prentice, Carol S.; Vassallo, Ricardo; Braucher, Regis; Larroque, Christophe; Arzhannikova, A.; Arzhanikov, S.; Mahan, Shannon; Massault, M.; Michelot, J-L.; Todbileg, M.</p> <p>2015-01-01</p> <p>The Bulnay <span class="hlt">earthquake</span> of July 23, 1905 (Mw 8.3-8.5), in north-central Mongolia, is one of the world's largest recorded intracontinental <span class="hlt">earthquakes</span> and one of four great <span class="hlt">earthquakes</span> that occurred in the region during the 20th century. The 375-km-long surface rupture of the left-lateral, strike-slip, N095°E trending Bulnay Fault associated with this <span class="hlt">earthquake</span> is remarkable for its pronounced expression across the landscape and for the size of features produced by previous <span class="hlt">earthquakes</span>. Our field observations suggest that in many areas the width and geometry of the rupture zone is the result of repeated <span class="hlt">earthquakes</span>; however, in those areas where it is possible to determine that the geomorphic features are the result of the 1905 surface rupture alone, the size of the features produced by this single <span class="hlt">earthquake</span> are singular in comparison to most other historical strike-slip surface ruptures worldwide. Along the 80 km stretch, between 97.18°E and 98.33°E, the fault zone is characterized by several meters width and the mean left-lateral 1905 offset is 8.9 ± 0.6 m with two measured cumulative offsets that are twice the 1905 slip. These observations suggest that the displacement produced during the penultimate event was similar to the 1905 slip. Morphotectonic analyses carried out at three sites along the eastern part of the Bulnay fault, allow us to estimate a mean horizontal slip <span class="hlt">rate</span> of 3.1 ± 1.7 mm/yr over the Late Pleistocene-Holocene period. In parallel, paleoseismological investigations show evidence for two <span class="hlt">earthquakes</span> prior to the 1905 event with <span class="hlt">recurrence</span> intervals of ~2700-4000 years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S21A0231L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S21A0231L"><span>A Virtual Tour of the 1868 Hayward <span class="hlt">Earthquake</span> in Google EarthTM</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lackey, H. G.; Blair, J. L.; Boatwright, J.; Brocher, T.</p> <p>2007-12-01</p> <p>The 1868 Hayward <span class="hlt">earthquake</span> has been overshadowed by the subsequent 1906 San Francisco <span class="hlt">earthquake</span> that destroyed much of San Francisco. Nonetheless, a modern <span class="hlt">recurrence</span> of the 1868 <span class="hlt">earthquake</span> would cause widespread damage to the densely populated Bay Area, particularly in the east Bay communities that have grown up virtually on top of the Hayward fault. Our concern is heightened by paleoseismic studies suggesting that the <span class="hlt">recurrence</span> interval for the past five <span class="hlt">earthquakes</span> on the southern Hayward fault is 140 to 170 years. Our objective is to build an educational web site that illustrates the cause and effect of the 1868 <span class="hlt">earthquake</span> drawing on scientific and historic information. We will use Google EarthTM software to visually illustrate complex scientific concepts in a way that is understandable to a non-scientific audience. This web site will lead the viewer from a regional summary of the plate tectonics and faulting system of western North America, to more specific information about the 1868 Hayward <span class="hlt">earthquake</span> itself. Text and Google EarthTM layers will include modeled shaking of the <span class="hlt">earthquake</span>, relocations of historic photographs, reconstruction of damaged buildings as 3-D models, and additional scientific data that may come from the many scientific studies conducted for the 140th anniversary of the event. <span class="hlt">Earthquake</span> engineering concerns will be stressed, including population density, vulnerable infrastructure, and lifelines. We will also present detailed maps of the Hayward fault, measurements of fault creep, and geologic evidence of its <span class="hlt">recurrence</span>. Understanding the science behind <span class="hlt">earthquake</span> hazards is an important step in preparing for the next significant <span class="hlt">earthquake</span>. We hope to communicate to the public and students of all ages, through visualizations, not only the cause and effect of the 1868 <span class="hlt">earthquake</span>, but also modern seismic hazards of the San Francisco Bay region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15900149','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15900149"><span>Mortality and <span class="hlt">recurrence</span> <span class="hlt">rate</span> after pressure ulcer operation for elderly long-term bedridden patients.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kuwahara, Masamitsu; Tada, Hideyuki; Mashiba, Kumi; Yurugi, Satoshi; Iioka, Hiroshi; Niitsuma, Katsunori; Yasuda, Yukiko</p> <p>2005-06-01</p> <p>We operated on 16 sacral pressure ulcers in elderly and long-term residential patients who were immobile as a result of cerebral vascular disease. The mean age of patients was 76 years. Eight ulcers were treated with local fascial flaps and 8 by simple closure. The follow-up period was from 1 to 4 years. <span class="hlt">Recurrence</span> and mortality <span class="hlt">rates</span> were examined retrospectively. In the 16 patients, <span class="hlt">recurrence</span> occurred in 37.5%, and 43.8% died without <span class="hlt">recurrence</span>. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> was 37.5% for local fascial flaps and 37.5% for simple closure. Overall mortality was 68.8% in the follow-up period. Because postoperative death was common, we should not only focus on reducing local pressure but also pay attention to any underlying disease. Because of this high mortality <span class="hlt">rate</span>, the least invasive procedure possible should be used. Because the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of simple closure was the same as for local fascial flaps, simple closure should be considered as a reconstructive method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1214244K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1214244K"><span>Living with <span class="hlt">earthquakes</span> - development and usage of <span class="hlt">earthquake</span>-resistant construction methods in European and Asian Antiquity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kázmér, Miklós; Major, Balázs; Hariyadi, Agus; Pramumijoyo, Subagyo; Ditto Haryana, Yohanes</p> <p>2010-05-01</p> <p><span class="hlt">Earthquakes</span> are among the most horrible events of nature due to unexpected occurrence, for which no spiritual means are available for protection. The only way of preserving life and property is applying <span class="hlt">earthquake</span>-resistant construction methods. Ancient Greek architects of public buildings applied steel clamps embedded in lead casing to hold together columns and masonry walls during frequent <span class="hlt">earthquakes</span> in the Aegean region. Elastic steel provided strength, while plastic lead casing absorbed minor shifts of blocks without fracturing rigid stone. Romans invented concrete and built all sizes of buildings as a single, unflexible unit. Masonry surrounding and decorating concrete core of the wall did not bear load. Concrete resisted minor shaking, yielding only to forces higher than fracture limits. Roman building traditions survived the Dark Ages and 12th century Crusader castles erected in <span class="hlt">earthquake</span>-prone Syria survive until today in reasonably good condition. Concrete and steel clamping persisted side-by-side in the Roman Empire. Concrete was used for cheap construction as compared to building of masonry. Applying lead-encased steel increased costs, and was avoided whenever possible. Columns of the various forums in Italian Pompeii mostly lack steel fittings despite situated in well-known <span class="hlt">earthquake</span>-prone area. Whether frequent <span class="hlt">recurrence</span> of <span class="hlt">earthquakes</span> in the Naples region was known to inhabitants of Pompeii might be a matter of debate. Seemingly the shock of the AD 62 <span class="hlt">earthquake</span> was not enough to apply well-known protective engineering methods throughout the reconstruction of the city before the AD 79 volcanic catastrophe. An independent engineering tradition developed on the island of Java (Indonesia). The mortar-less construction technique of 8-9th century Hindu masonry shrines around Yogyakarta would allow scattering of blocks during <span class="hlt">earthquakes</span>. To prevent dilapidation an intricate mortise-and-tenon system was carved into adjacent faces of blocks. Only the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70024773','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70024773"><span>Stress triggering of the 1999 Hector Mine <span class="hlt">earthquake</span> by transient deformation following the 1992 Landers <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pollitz, F.F.; Sacks, I.S.</p> <p>2002-01-01</p> <p>The M 7.3 June 28, 1992 Landers and M 7.1 October 16, 1999 Hector Mine <span class="hlt">earthquakes</span>, California, both right lateral strike-slip events on NNW-trending subvertical faults, occurred in close proximity in space and time in a region where <span class="hlt">recurrence</span> times for surface-rupturing <span class="hlt">earthquakes</span> are thousands of years. This suggests a causal role for the Landers <span class="hlt">earthquake</span> in triggering the Hector Mine <span class="hlt">earthquake</span>. Previous modeling of the static stress change associated with the Landers <span class="hlt">earthquake</span> shows that the area of peak Hector Mine slip lies where the Coulomb failure stress promoting right-lateral strike-slip failure was high, but the nucleation point of the Hector Mine rupture was neutrally to weakly promoted, depending on the assumed coefficient of friction. Possible explanations that could account for the 7-year delay between the two ruptures include background tectonic stressing, dissipation of fluid pressure gradients, <span class="hlt">rate</span>- and state-dependent friction effects, and post-Landers viscoelastic relaxation of the lower crust and upper mantle. By employing a viscoelastic model calibrated by geodetic data collected during the time period between the Landers and Hector Mine events, we calculate that postseismic relaxation produced a transient increase in Coulomb failure stress of about 0.7 bars on the impending Hector Mine rupture surface. The increase is greatest over the broad surface that includes the 1999 nucleation point and the site of peak slip further north. Since stress changes of magnitude greater than or equal to 0.1 bar are associated with documented causal fault interactions elsewhere, viscoelastic relaxation likely contributed to the triggering of the Hector Mine <span class="hlt">earthquake</span>. This interpretation relies on the assumption that the faults occupying the central Mojave Desert (i.e., both the Landers and Hector Mine rupturing faults) were critically stressed just prior to the Landers <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991JSG....13..137M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991JSG....13..137M"><span>The Wasatch fault zone, utah—segmentation and history of Holocene <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Machette, Michael N.; Personius, Stephen F.; Nelson, Alan R.; Schwartz, David P.; Lund, William R.</p> <p></p> <p>The Wasatch fault zone (WFZ) forms the eastern boundary of the Basin and Range province and is the longest continuous, active normal fault (343 km) in the United States. It underlies an urban corridor of 1.6 million people (80% of Utah's population) representing the largest <span class="hlt">earthquake</span> risk in the interior of the western United States. We have used paleoseismological data to identify 10 discrete segments of the WFZ. Five are active, medial segments with Holocene slip <span class="hlt">rates</span> of 1-2 mm a -1, <span class="hlt">recurrence</span> intervals of 2000-4000 years and average lengths of about 50 km. Five are less active, distal segments with mostly pre-Holocene surface ruptures, late Quaternary slip <span class="hlt">rates</span> of <0.5 mm a -1 <span class="hlt">recurrence</span> intervals of ≥10,000 years and average lengths of about 20 km. Surface-faulting events on each of the medial segments of the WFZ formed 2-4-m-high scarps repeatedly during the Holocene; latest Pleistocene (14-15 ka) deposits commonly have scarps as much as 15-20 m in height. Segments identified from paleoseismological studies of other major late Quaternary normal faults in the northern Basin and Range province are 20-25 km long, or about half of that proposed for the medial segments of the WFZ. Paleoseismological records for the past 6000 years indicate that a major surface-rupturing <span class="hlt">earthquake</span> has occurred along one of the medial segments about every 395 ± 60 years. However, between about 400 and 1500 years ago, the WFZ experienced six major surface-rupturing events, an average of one event every 220 years, or about twice as often as expected from the 6000-year record. This pattern of temporal clustering is similar to that of the central Nevada—eastern California Seismic Belt in the western part of the Basin and Range province, where 11 <span class="hlt">earthquakes</span> of M > 6.5 have occurred since 1860. Although the time scale of the clustering is different—130 years vs 1100 years—we consider the central Nevada—eastern California Seismic Belt to be a historic analog for movement on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.T11A2276M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.T11A2276M"><span>Structural Constraints and <span class="hlt">Earthquake</span> <span class="hlt">Recurrence</span> Estimates for the West Tahoe-Dollar Point Fault, Lake Tahoe Basin, California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maloney, J. M.; Driscoll, N. W.; Kent, G.; Brothers, D. S.; Baskin, R. L.; Babcock, J. M.; Noble, P. J.; Karlin, R. E.</p> <p>2011-12-01</p> <p>Previous work in the Lake Tahoe Basin (LTB), California, identified the West Tahoe-Dollar Point Fault (WTDPF) as the most hazardous fault in the region. Onshore and offshore geophysical mapping delineated three segments of the WTDPF extending along the western margin of the LTB. The rupture patterns between the three WTDPF segments remain poorly understood. Fallen Leaf Lake (FLL), Cascade Lake, and Emerald Bay are three sub-basins of the LTB, located south of Lake Tahoe, that provide an opportunity to image primary <span class="hlt">earthquake</span> deformation along the WTDPF and associated landslide deposits. We present results from recent (June 2011) high-resolution seismic CHIRP surveys in FLL and Cascade Lake, as well as complete multibeam swath bathymetry coverage of FLL. Radiocarbon dates obtained from the new piston cores acquired in FLL provide age constraints on the older FLL slide deposits and build on and complement previous work that dated the most recent event (MRE) in Fallen Leaf Lake at ~4.1-4.5 k.y. BP. The CHIRP data beneath FLL image slide deposits that appear to correlate with contemporaneous slide deposits in Emerald Bay and Lake Tahoe. A major slide imaged in FLL CHIRP data is slightly younger than the Tsoyowata ash (7950-7730 cal yrs BP) identified in sediment cores and appears synchronous with a major Lake Tahoe slide deposit (7890-7190 cal yrs BP). The equivalent age of these slides suggests the penultimate <span class="hlt">earthquake</span> on the WTDPF may have triggered them. If correct, we postulate a <span class="hlt">recurrence</span> interval of ~3-4 k.y. These results suggest the FLL segment of the WTDPF is near its seismic <span class="hlt">recurrence</span> cycle. Additionally, CHIRP profiles acquired in Cascade Lake image the WTDPF for the first time in this sub-basin, which is located near the transition zone between the FLL and Rubicon Point Sections of the WTDPF. We observe two fault-strands trending N45°W across southern Cascade Lake for ~450 m. The strands produce scarps of ~5 m and ~2.7 m, respectively, on the lake</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030020856','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030020856"><span>Crustal Deformation in Southcentral Alaska: The 1964 Prince William Sound <span class="hlt">Earthquake</span> Subduction Zone</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Cohen, Steven C.; Freymueller, Jeffrey T.</p> <p>2003-01-01</p> <p> throughout the several hundred year <span class="hlt">recurrence</span> time for great <span class="hlt">earthquake</span>. The nearly 10 mm/yr uplift <span class="hlt">rate</span> at Seldovia on the Kenai Peninsula is an example.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRB..122.5691W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRB..122.5691W"><span>A 667 year record of coseismic and interseismic Coulomb stress changes in central Italy reveals the role of fault interaction in controlling irregular <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wedmore, L. N. J.; Faure Walker, J. P.; Roberts, G. P.; Sammonds, P. R.; McCaffrey, K. J. W.; Cowie, P. A.</p> <p>2017-07-01</p> <p>Current studies of fault interaction lack sufficiently long <span class="hlt">earthquake</span> records and measurements of fault slip <span class="hlt">rates</span> over multiple seismic cycles to fully investigate the effects of interseismic loading and coseismic stress changes on the surrounding fault network. We model elastic interactions between 97 faults from 30 <span class="hlt">earthquakes</span> since 1349 A.D. in central Italy to investigate the relative importance of co-seismic stress changes versus interseismic stress accumulation for <span class="hlt">earthquake</span> occurrence and fault interaction. This region has an exceptionally long, 667 year record of historical <span class="hlt">earthquakes</span> and detailed constraints on the locations and slip <span class="hlt">rates</span> of its active normal faults. Of 21 <span class="hlt">earthquakes</span> since 1654, 20 events occurred on faults where combined coseismic and interseismic loading stresses were positive even though 20% of all faults are in "stress shadows" at any one time. Furthermore, the Coulomb stress on the faults that experience <span class="hlt">earthquakes</span> is statistically different from a random sequence of <span class="hlt">earthquakes</span> in the region. We show how coseismic Coulomb stress changes can alter <span class="hlt">earthquake</span> interevent times by 103 years, and fault length controls the intensity of this effect. Static Coulomb stress changes cause greater interevent perturbations on shorter faults in areas characterized by lower strain (or slip) <span class="hlt">rates</span>. The exceptional duration and number of <span class="hlt">earthquakes</span> we model enable us to demonstrate the importance of combining long <span class="hlt">earthquake</span> records with detailed knowledge of fault geometries, slip <span class="hlt">rates</span>, and kinematics to understand the impact of stress changes in complex networks of active faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNH13A1366L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNH13A1366L"><span>Linking giant <span class="hlt">earthquakes</span> with the subduction of oceanic fracture zones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Landgrebe, T. C.; Müller, R. D.; EathByte Group</p> <p>2011-12-01</p> <p>Giant subduction <span class="hlt">earthquakes</span> are known to occur in areas not previously identified as prone to high seismic risk. This highlights the need to better identify subduction zone segments potentially dominated by relatively long (up to 1000 years and more) <span class="hlt">recurrence</span> times of giant <span class="hlt">earthquakes</span>. Global digital data sets represent a promising source of information for a multi-dimensional <span class="hlt">earthquake</span> hazard analysis. We combine the NGDC global Significant <span class="hlt">Earthquakes</span> database with a global strain <span class="hlt">rate</span> map, gridded ages of the ocean floor, and a recently produced digital data set for oceanic fracture zones, major aseismic ridges and volcanic chains to investigate the association of <span class="hlt">earthquakes</span> as a function of magnitude with age of the downgoing slab and convergence <span class="hlt">rates</span>. We use a so-called Top-N recommendation method, a technology originally developed to search, sort, classify, and filter very large and often statistically skewed data sets on the internet, to analyse the association of subduction <span class="hlt">earthquakes</span> sorted by magnitude with key parameters. The Top-N analysis is used to progressively assess how strongly particular "tectonic niche" locations (e.g. locations along subduction zones intersected with aseismic ridges or volcanic chains) are associated with sets of <span class="hlt">earthquakes</span> in sorted order in a given magnitude range. As the total number N of sorted <span class="hlt">earthquakes</span> is increased, by progressively including smaller-magnitude events, the so-called recall is computed, defined as the number of Top-N <span class="hlt">earthquakes</span> associated with particular target areas divided by N. The resultant statistical measure represents an intuitive description of the effectiveness of a given set of parameters to account for the location of significant <span class="hlt">earthquakes</span> on record. We use this method to show that the occurrence of great (magnitude ≥ 8) <span class="hlt">earthquakes</span> on overriding plate segments is strongly biased towards intersections of oceanic fracture zones with subduction zones. These intersection regions are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S21B0704S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S21B0704S"><span>Break of slope in <span class="hlt">earthquake</span> size distribution and creep <span class="hlt">rate</span> along the San Andreas Fault system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shebalin, P.; Narteau, C.; Vorobieva, I.</p> <p>2017-12-01</p> <p>Crustal faults accommodate slip either by a succession of <span class="hlt">earthquakes</span> or continuous slip, andin most instances, both these seismic and aseismic processes coexist. Recorded seismicity and geodeticmeasurements are therefore two complementary data sets that together document ongoing deformationalong active tectonic structures. Here we study the influence of stable sliding on <span class="hlt">earthquake</span> statistics.We show that creep along the San Andreas Fault is responsible for a break of slope in the <span class="hlt">earthquake</span> sizedistribution. This slope increases with an increasing creep <span class="hlt">rate</span> for larger magnitude ranges, whereas itshows no systematic dependence on creep <span class="hlt">rate</span> for smaller magnitude ranges. This is interpreted as a deficitof large events under conditions of faster creep where seismic ruptures are less likely to propagate. Theseresults suggest that the <span class="hlt">earthquake</span> size distribution does not only depend on the level of stress but also onthe type of deformation.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GSL.....4....7H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GSL.....4....7H"><span>Historical <span class="hlt">earthquake</span> research in Austria</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hammerl, Christa</p> <p>2017-12-01</p> <p>Austria has a moderate seismicity, and on average the population feels 40 <span class="hlt">earthquakes</span> per year or approximately three <span class="hlt">earthquakes</span> per month. A severe <span class="hlt">earthquake</span> with light building damage is expected roughly every 2 to 3 years in Austria. Severe damage to buildings ( I 0 > 8° EMS) occurs significantly less frequently, the average period of <span class="hlt">recurrence</span> is about 75 years. For this reason the historical <span class="hlt">earthquake</span> research has been of special importance in Austria. The interest in historical <span class="hlt">earthquakes</span> in the past in the Austro-Hungarian Empire is outlined, beginning with an initiative of the Austrian Academy of Sciences and the development of historical <span class="hlt">earthquake</span> research as an independent research field after the 1978 "Zwentendorf plebiscite" on whether the nuclear power plant will start up. The applied methods are introduced briefly along with the most important studies and last but not least as an example of a recently carried out case study, one of the strongest past <span class="hlt">earthquakes</span> in Austria, the <span class="hlt">earthquake</span> of 17 July 1670, is presented. The research into historical <span class="hlt">earthquakes</span> in Austria concentrates on seismic events of the pre-instrumental period. The investigations are not only of historical interest, but also contribute to the completeness and correctness of the Austrian <span class="hlt">earthquake</span> catalogue, which is the basis for seismic hazard analysis and as such benefits the public, communities, civil engineers, architects, civil protection, and many others.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70025181','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70025181"><span>Unusually large <span class="hlt">earthquakes</span> inferred from tsunami deposits along the Kuril trench</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nanayama, F.; Satake, K.; Furukawa, R.; Shimokawa, K.; Atwater, B.F.; Shigeno, K.; Yamaki, S.</p> <p>2003-01-01</p> <p>The Pacific plate converges with northeastern Eurasia at a <span class="hlt">rate</span> of 8-9 m per century along the Kamchatka, Kuril and Japan trenches. Along the southern Kuril trench, which faces the Japanese island of Hokkaido, this fast subduction has <span class="hlt">recurrently</span> generated <span class="hlt">earthquakes</span> with magnitudes of up to ???8 over the past two centuries. These historical events, on rupture segments 100-200 km long, have been considered characteristic of Hokkaido's plate-boundary <span class="hlt">earthquakes</span>. But here we use deposits of prehistoric tsunamis to infer the infrequent occurrence of larger <span class="hlt">earthquakes</span> generated from longer ruptures. Many of these tsunami deposits form sheets of sand that extend kilometres inland from the deposits of historical tsunamis. Stratigraphic series of extensive sand sheets, intercalated with dated volcanic-ash layers, show that such unusually large tsunamis occurred about every 500 years on average over the past 2,000-7,000 years, most recently ???350 years ago. Numerical simulations of these tsunamis are best explained by <span class="hlt">earthquakes</span> that individually rupture multiple segments along the southern Kuril trench. We infer that such multi-segment <span class="hlt">earthquakes</span> persistently recur among a larger number of single-segment events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T23F0689M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T23F0689M"><span>Stress and Strain <span class="hlt">Rates</span> from Faults Reconstructed by <span class="hlt">Earthquakes</span> Relocalization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morra, G.; Chiaraluce, L.; Di Stefano, R.; Michele, M.; Cambiotti, G.; Yuen, D. A.; Brunsvik, B.</p> <p>2017-12-01</p> <p><span class="hlt">Recurrence</span> of main <span class="hlt">earthquakes</span> on the same fault depends on kinematic setting, hosting lithologies and fault geometry and population. Northern and central Italy transitioned from convergence to post-orogenic extension. This has produced a unique and very complex tectonic setting characterized by superimposed normal faults, crossing different geologic domains, that allows to investigate a variety of seismic manifestations. In the past twenty years three seismic sequences (1997 Colfiorito, 2009 L'Aquila and 2016-17 Amatrice-Norcia-Visso) activated a 150km long normal fault system located between the central and northern apennines and allowing the recordings of thousands of seismic events. Both the 1997 and the 2009 main shocks were preceded by a series of small pre-shocks occurring in proximity to the future largest events. It has been proposed and modelled that the seismicity pattern of the two foreshocks sequences was caused by active dilatancy phenomenon, due to fluid flow in the source area. Seismic activity has continued intensively until three events with 6.0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19162429','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19162429"><span>Low <span class="hlt">rates</span> of loco-regional <span class="hlt">recurrence</span> following extended lymph node dissection for gastric cancer.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Muratore, A; Zimmitti, G; Lo Tesoriere, R; Mellano, A; Massucco, P; Capussotti, L</p> <p>2009-06-01</p> <p>The study by MacDonald et al. [Chemoradiotherapy after surgery compared with surgery alone for adenocarcinoma of the stomach or gastroesophageal junction. N Engl J Med 2001;345:725-30] has reported low loco-regional <span class="hlt">recurrence</span> <span class="hlt">rates</span> (19%) after gastric cancer resection and adjuvant radiotherapy. However, the lymph node dissection was often "inadequate". The aim of this retrospective study is to analyse if an extended lymph node dissection (D2) without adjuvant radiotherapy may achieve comparable loco-regional <span class="hlt">recurrence</span> <span class="hlt">rates</span>. A prospective database of 200 patients who underwent a curative resection for gastric carcinoma from January 2000 to December 2006 was analysed. D2 lymph node dissection was standard. <span class="hlt">Recurrences</span> were categorized as loco-regional, peritoneal, or distant. No patients received neoadjuvant or adjuvant radiotherapy. The in-hospital mortality <span class="hlt">rate</span> was 1% (2 patients). The mean number of dissected lymph nodes was 25.9. Overall and disease-free survival at 5years were 60.7% and 61.2% respectively. During the follow-up, 60 patients (30%) have recurred at 76 sites: 38 (50%) distant metastases, 25 (32.9%) peritoneal metastases, and 13 (17.1%) loco-regional <span class="hlt">recurrences</span>. The loco-regional <span class="hlt">recurrence</span> was isolated in 6 patients and associated with peritoneal or distant metastases in 7 patients. The mean time to the first <span class="hlt">recurrence</span> was 18.9 (95% confidence interval: 15.0-21.9) months. Extended lymph node dissection is safe and warrants low loco-regional <span class="hlt">recurrence</span> <span class="hlt">rates</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70169013','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70169013"><span>Perspectives on <span class="hlt">earthquake</span> hazards in the New Madrid seismic zone, Missouri</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Thenhaus, P.C.</p> <p>1990-01-01</p> <p>A sequence of three great <span class="hlt">earthquakes</span> struck the Central United States during the winter of 1811-1812 in the area of New Madrid, Missouri. they are considered to be the greatest <span class="hlt">earthquakes</span> in the conterminous U.S because they were felt and caused damage at far greater distances than any other <span class="hlt">earthquakes</span> in U.S history. The large population currently living within the damage area of these <span class="hlt">earthquakes</span> means that widespread destruction and loss of life is likely if the sequence were repeated. In contrast to California, where the <span class="hlt">earthquakes</span> are felt frequently, the damaging <span class="hlt">earthquakes</span> that have occurred in the Easter U.S-in 155 (Cape Ann, Mass.), 1811-12 (New Madrid, Mo.), 1886 (Charleston S.C) ,and 1897 (Giles County, Va.- are generally regarded as only historical phenomena (fig. 1). The social memory of these <span class="hlt">earthquakes</span> no longer exists. A fundamental problem in the Eastern U.S, therefore, is that the <span class="hlt">earthquake</span> hazard is not generally considered today in land-use and civic planning. This article offers perspectives on the <span class="hlt">earthquake</span> hazard of the New Madrid seismic zone through discussions of the geology of the Mississippi Embayment, the historical <span class="hlt">earthquakes</span> that have occurred there, the <span class="hlt">earthquake</span> risk, and the "tools" that geoscientists have to study the region. The so-called <span class="hlt">earthquake</span> hazard is defined  by the characterization of the physical attributes of the geological structures that cause <span class="hlt">earthquakes</span>, the estimation of the <span class="hlt">recurrence</span> times of the <span class="hlt">earthquakes</span>, the estimation of the <span class="hlt">recurrence</span> times of the <span class="hlt">earthquakes</span>, their potential size, and the expected ground motions. the term "<span class="hlt">earthquake</span> risk," on the other hand, refers to aspects of the expected damage to manmade strctures and to lifelines as a result of the <span class="hlt">earthquake</span> hazard.  </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.T13A2346M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.T13A2346M"><span>Fault healing and <span class="hlt">earthquake</span> spectra from stick slip sequences in the laboratory and on active faults</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McLaskey, G. C.; Glaser, S. D.; Thomas, A.; Burgmann, R.</p> <p>2011-12-01</p> <p>Repeating <span class="hlt">earthquake</span> sequences (RES) are thought to occur on isolated patches of a fault that fail in repeated stick-slip fashion. RES enable researchers to study the effect of variations in <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> time and the relationship between fault healing and <span class="hlt">earthquake</span> generation. Fault healing is thought to be the physical process responsible for the 'state' variable in widely used <span class="hlt">rate</span>- and state-dependent friction equations. We analyze RES created in laboratory stick slip experiments on a direct shear apparatus instrumented with an array of very high frequency (1KHz - 1MHz) displacement sensors. Tests are conducted on the model material polymethylmethacrylate (PMMA). While frictional properties of this glassy polymer can be characterized with the <span class="hlt">rate</span>- and state- dependent friction laws, the <span class="hlt">rate</span> of healing in PMMA is higher than room temperature rock. Our experiments show that in addition to a modest increase in fault strength and stress drop with increasing healing time, there are distinct spectral changes in the recorded laboratory <span class="hlt">earthquakes</span>. Using the impact of a tiny sphere on the surface of the test specimen as a known source calibration function, we are able to remove the instrument and apparatus response from recorded signals so that the source spectrum of the laboratory <span class="hlt">earthquakes</span> can be accurately estimated. The rupture of a fault that was allowed to heal produces a laboratory <span class="hlt">earthquake</span> with increased high frequency content compared to one produced by a fault which has had less time to heal. These laboratory results are supported by observations of RES on the Calaveras and San Andreas faults, which show similar spectral changes when <span class="hlt">recurrence</span> time is perturbed by a nearby large <span class="hlt">earthquake</span>. Healing is typically attributed to a creep-like relaxation of the material which causes the true area of contact of interacting asperity populations to increase with time in a quasi-logarithmic way. The increase in high frequency seismicity shown here</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29479838','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29479838"><span>Estimating the effect of a rare time-dependent treatment on the <span class="hlt">recurrent</span> event <span class="hlt">rate</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Smith, Abigail R; Zhu, Danting; Goodrich, Nathan P; Merion, Robert M; Schaubel, Douglas E</p> <p>2018-05-30</p> <p>In many observational studies, the objective is to estimate the effect of treatment or state-change on the <span class="hlt">recurrent</span> event <span class="hlt">rate</span>. If treatment is assigned after the start of follow-up, traditional methods (eg, adjustment for baseline-only covariates or fully conditional adjustment for time-dependent covariates) may give biased results. We propose a two-stage modeling approach using the method of sequential stratification to accurately estimate the effect of a time-dependent treatment on the <span class="hlt">recurrent</span> event <span class="hlt">rate</span>. At the first stage, we estimate the pretreatment <span class="hlt">recurrent</span> event trajectory using a proportional <span class="hlt">rates</span> model censored at the time of treatment. Prognostic scores are estimated from the linear predictor of this model and used to match treated patients to as yet untreated controls based on prognostic score at the time of treatment for the index patient. The final model is stratified on matched sets and compares the posttreatment <span class="hlt">recurrent</span> event <span class="hlt">rate</span> to the <span class="hlt">recurrent</span> event <span class="hlt">rate</span> of the matched controls. We demonstrate through simulation that bias due to dependent censoring is negligible, provided the treatment frequency is low, and we investigate a threshold at which correction for dependent censoring is needed. The method is applied to liver transplant (LT), where we estimate the effect of development of post-LT End Stage Renal Disease (ESRD) on <span class="hlt">rate</span> of days hospitalized. Copyright © 2018 John Wiley & Sons, Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189423','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189423"><span>The effects of varying injection <span class="hlt">rates</span> in Osage County, Oklahoma, on the 2016 Mw5.8 Pawnee <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Barbour, Andrew J.; Norbeck, Jack H.; Rubinstein, Justin L.</p> <p>2017-01-01</p> <p>The 2016 Mw 5.8 Pawnee <span class="hlt">earthquake</span> occurred in a region with active wastewater injection into a basal formation group. Prior to the <span class="hlt">earthquake</span>, fluid injection <span class="hlt">rates</span> at most wells were relatively steady, but newly collected data show significant increases in injection <span class="hlt">rate</span> in the years leading up to <span class="hlt">earthquake</span>. For the same time period, the total volumes of injected wastewater were roughly equivalent between variable‐<span class="hlt">rate</span> and constant‐<span class="hlt">rate</span> wells. To understand the possible influence of these changes in injection, we simulate the variable‐<span class="hlt">rate</span> injection history and its constant‐<span class="hlt">rate</span> equivalent in a layered poroelastic half‐space to explore the interplay between pore‐pressure effects and poroelastic effects on the fault leading up to the mainshock. In both cases, poroelastic stresses contribute a significant proportion of Coulomb failure stresses on the fault compared to pore‐pressure increases alone, but the resulting changes in seismicity <span class="hlt">rate</span>, calculated using a rate‐and‐state frictional model, are many times larger when poroelastic effects are included, owing to enhanced stressing <span class="hlt">rates</span>. In particular, the variable‐<span class="hlt">rate</span> simulation predicts more than an order of magnitude increase in seismicity <span class="hlt">rate</span> above background <span class="hlt">rates</span> compared to the constant‐<span class="hlt">rate</span> simulation with equivalent volume. The observed cumulative density of <span class="hlt">earthquakes</span> prior to the mainshock within 10 km of the injection source exhibits remarkable agreement with seismicity predicted by the variable‐<span class="hlt">rate</span> injection case.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70048548','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70048548"><span>Fault healing promotes high-frequency <span class="hlt">earthquakes</span> in laboratory experiments and on natural faults</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McLaskey, Gregory C.; Thomas, Amanda M.; Glaser, Steven D.; Nadeau, Robert M.</p> <p>2012-01-01</p> <p>Faults strengthen or heal with time in stationary contact and this healing may be an essential ingredient for the generation of <span class="hlt">earthquakes</span>. In the laboratory, healing is thought to be the result of thermally activated mechanisms that weld together micrometre-sized asperity contacts on the fault surface, but the relationship between laboratory measures of fault healing and the seismically observable properties of <span class="hlt">earthquakes</span> is at present not well defined. Here we report on laboratory experiments and seismological observations that show how the spectral properties of <span class="hlt">earthquakes</span> vary as a function of fault healing time. In the laboratory, we find that increased healing causes a disproportionately large amount of high-frequency seismic radiation to be produced during fault rupture. We observe a similar connection between <span class="hlt">earthquake</span> spectra and <span class="hlt">recurrence</span> time for repeating <span class="hlt">earthquake</span> sequences on natural faults. Healing <span class="hlt">rates</span> depend on pressure, temperature and mineralogy, so the connection between seismicity and healing may help to explain recent observations of large megathrust <span class="hlt">earthquakes</span> which indicate that energetic, high-frequency seismic radiation originates from locations that are distinct from the geodetically inferred locations of large-amplitude fault slip</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/1995/257/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/1995/257/"><span>Seismic Sources and <span class="hlt">Recurrence</span> <span class="hlt">Rates</span> as Adopted by USGS Staff for the Production of the 1982 and 1990 Probabilistic Ground Motion Maps for Alaska and the Conterminous United States</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hanson, Stanley L.; Perkins, David M.</p> <p>1995-01-01</p> <p>The construction of a probabilistic ground-motion hazard map for a region follows a sequence of analyses beginning with the selection of an <span class="hlt">earthquake</span> catalog and ending with the mapping of calculated probabilistic ground-motion values (Hanson and others, 1992). An integral part of this process is the creation of sources used for the calculation of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span> and ground motions. These sources consist of areas and lines that are representative of geologic or tectonic features and faults. After the design of the sources, it is necessary to arrange the coordinate points in a particular order compatible with the input format for the SEISRISK-III program (Bender and Perkins, 1987). Source zones are usually modeled as a point-rupture source. Where applicable, linear rupture sources are modeled with articulated lines, representing known faults, or a field of parallel lines, representing a generalized distribution of hypothetical faults. Based on the distribution of <span class="hlt">earthquakes</span> throughout the individual source zones (or a collection of several sources), <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span> are computed for each of the sources, and a minimum and maximum magnitude is assigned. Over a period of time from 1978 to 1980 several conferences were held by the USGS to solicit information on regions of the United States for the purpose of creating source zones for computation of probabilistic ground motions (Thenhaus, 1983). As a result of these regional meetings and previous work in the Pacific Northwest, (Perkins and others, 1980), California continental shelf, (Thenhaus and others, 1980), and the Eastern outer continental shelf, (Perkins and others, 1979) a consensus set of source zones was agreed upon and subsequently used to produce a national ground motion hazard map for the United States (Algermissen and others, 1982). In this report and on the accompanying disk we provide a complete list of source areas and line sources as used for the 1982 and later 1990 seismic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.T13D2568M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T13D2568M"><span>New constraints on the late Quaternary slip <span class="hlt">rate</span> and <span class="hlt">earthquake</span> history of the Kalabagh fault from geomorphic mapping: Implications for slip <span class="hlt">rate</span> and <span class="hlt">earthquake</span> potential of the western Salt Range thrust</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Madugo, C. M.; Meigs, A.; Ramzan, S.</p> <p>2013-12-01</p> <p>Whether the basal décollement ruptures in great <span class="hlt">earthquakes</span> and at what <span class="hlt">rate</span> it slips are open questions for the Pakistani Himalaya. The fact that the southern expression of the décollement, the Salt Range thrust (SRT) is localized in a thick evaporate deposit implies the fault has low strength. The lack of a strong motion event in historic records suggests no large <span class="hlt">earthquakes</span> have struck this region in the past 2000 years. Because 101 year GPS geodetic slip <span class="hlt">rates</span> for the SRT (~3 mm/yr) are up to four times lower than 106 year geologic <span class="hlt">rates</span> (9-14 mm/yr), it is unknown whether the convergence <span class="hlt">rate</span> has decreased over time, or whether the geodetic data reflect a transient phenomenon such as fault creep on the SRT. To evaluate these end members, we obtained intermediate term (104 yr) slip <span class="hlt">rates</span> from offset geomorphic markers along the Kalabagh fault (KF). The KF is a structurally complex tear fault and lateral ramp that bounds the western side of the SRT. The bending of the western end of the SRT into the KF, and their similar geologic slip <span class="hlt">rates</span>, suggest the faults are kinematically linked. Thus intermediate-scale slip <span class="hlt">rates</span> and perhaps <span class="hlt">earthquake</span> history for the KF represent a proxy for behavior of the SRT. On a section of the KF that exhibits geomorphic evidence of primarily strike slip motion, we identify two partially eroded alluvial fan apexes that are offset up to 300×25 m and 210×30 m from their source channels. Fan reconstructions suggest the offsets are probably not significantly lower than these values. Optically stimulated luminescence (OSL) ages of 23×3 ka and 16×2 ka constrain fan surface abandonment. Assuming that fan abandonment accompanied offset by the KF, both fans yield nearly identical slip <span class="hlt">rates</span> of 13×3 mm/yr and 13×4 mm/yr for the KF. Within uncertainty, these <span class="hlt">rates</span> are at the high end of the geologic <span class="hlt">rate</span> for the KF and SRT, and at least several times higher than the geodetic <span class="hlt">rate</span> for the SRT. We also identify evidence of liquefaction</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70024397','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70024397"><span>The <span class="hlt">earthquake</span> potential of the New Madrid seismic zone</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Tuttle, Martitia P.; Schweig, Eugene S.; Sims, John D.; Lafferty, Robert H.; Wolf, Lorraine W.; Haynes, Marion L.</p> <p>2002-01-01</p> <p>The fault system responsible for New Madrid seismicity has generated temporally clustered very large <span class="hlt">earthquakes</span> in A.D. 900 ± 100 years and A.D. 1450 ± 150 years as well as in 1811–1812. Given the uncertainties in dating liquefaction features, the time between the past three New Madrid events may be as short as 200 years and as long as 800 years, with an average of 500 years. This advance in understanding the Late Holocene history of the New Madrid seismic zone and thus, the contemporary tectonic behavior of the associated fault system was made through studies of hundreds of <span class="hlt">earthquake</span>-induced liquefaction features at more than 250 sites across the New Madrid region. We have found evidence that prehistoric sand blows, like those that formed during the 1811–1812 <span class="hlt">earthquakes</span>, are probably compound structures resulting from multiple <span class="hlt">earthquakes</span> closely clustered in time or <span class="hlt">earthquake</span> sequences. From the spatial distribution and size of sand blows and their sedimentary units, we infer the source zones and estimate the magnitudes of <span class="hlt">earthquakes</span> within each sequence and thereby characterize the detailed behavior of the fault system. It appears that fault rupture was complex and that the central branch of the seismic zone produced very large <span class="hlt">earthquakes</span> during the A.D. 900 and A.D. 1450 events as well as in 1811–1812. On the basis of a minimum <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 200 years, we are now entering the period during which the next 1811–1812-type event could occur.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25859994','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25859994"><span>Low <span class="hlt">rates</span> of <span class="hlt">recurrence</span> after successful treatment of multidrug-resistant tuberculosis in Tomsk, Russia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gelmanova, I Y; Ahmad Khan, F; Becerra, M C; Zemlyanaya, N A; Unakova, I A; Andreev, Y G; Berezina, V I; Pavlova, V E; Shin, S; Yedilbayev, A B; Krasnov, V A; Keshavjee, S</p> <p>2015-04-01</p> <p>Tomsk, Russia, where multidrug-resistant tuberculosis (MDR-TB) is prevalent. To report <span class="hlt">rates</span> of <span class="hlt">recurrence</span> following successful treatment of MDR-TB in a program providing individualized treatment regimens designed according to the current global standard of care. A retrospective cohort study of 408 adults successfully treated for pulmonary MDR-TB from 10 September 2000 to 1 November 2004, and followed for up to 6 years post-treatment. We used Poisson regression with generalized estimating equations to assess whether <span class="hlt">recurrence</span> <span class="hlt">rates</span> changed significantly with time. We analyzed 399 (97.5%) patients with at least one follow-up visit (15 850 person-months of observation [PMO]). Baseline resistance to second-line drugs was common (65.2%); 398 patients (99.7%) were human immunodeficiency virus (HIV) negative. In the first year of post-treatment follow-up, there were six episodes of <span class="hlt">recurrence</span> (1.4/1000 PMO, 95%CI 0.5-3.0). After the first post-treatment year, there were 21 episodes of <span class="hlt">recurrence</span> (1.8/1000 PMO, 95%CI 1.1-2.8). The <span class="hlt">rate</span> did not change significantly with time. Individualized regimens designed according to the current global standard of care achieved low <span class="hlt">rates</span> of MDR-TB <span class="hlt">recurrence</span> among non-HIV-infected persons treated in a programmatic setting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GSL.....4...26S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GSL.....4...26S"><span>Introduction to thematic collection "Historical and geological studies of <span class="hlt">earthquakes</span>"</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Satake, Kenji; Wang, Jian; Hammerl, Christa; Malik, Javed N.</p> <p>2017-12-01</p> <p>This thematic collection contains eight papers mostly presented at the 2016 AOGS meeting in Beijing. Four papers describe historical <span class="hlt">earthquake</span> studies in Europe, Japan, and China; one paper uses modern instrumental data to examine the effect of giant <span class="hlt">earthquakes</span> on the seismicity <span class="hlt">rate</span>; and three papers describe paleoseismological studies using tsunami deposit in Japan, marine terraces in Philippines, and active faults in Himalayas. Hammerl (Geosci Lett 4:7, 2017) introduced historical seismological studies in Austria, starting from methodology which is state of the art in most European countries, followed by a case study for an <span class="hlt">earthquake</span> of July 17, 1670 in Tyrol. Albini and Rovida (Geosci Lett 3:30, 2016) examined 114 historical records for the <span class="hlt">earthquake</span> on April 6, 1667 on the east coast of the Adriatic Sea, compiled 37 Macroseismic Data Points, and estimated the epicenter and the size of the <span class="hlt">earthquake</span>. Matsu'ura (Geosci Lett 4:3, 2017) summarized historical <span class="hlt">earthquake</span> studies in Japan which resulted in about 8700 Intensity Data Points, assigned epicenters for 214 <span class="hlt">earthquakes</span> between AD 599 and 1872, and estimated focal depth and magnitudes for 134 events. Wang et al. (Geosci Lett 4:4, 2017) introduced historical seismology in China, where historical <span class="hlt">earthquake</span> archives include about 15,000 sources, and parametric catalogs include about 1000 historical <span class="hlt">earthquakes</span> between 2300 BC and AD 1911. Ishibe et al. (Geosci Lett 4:5, 2017) tested the Coulomb stress triggering hypothesis for three giant (M 9) <span class="hlt">earthquakes</span> that occurred in recent years, and found that at least the 2004 Sumatra-Andaman and 2011 Tohoku <span class="hlt">earthquakes</span> caused the seismicity <span class="hlt">rate</span> change. Ishimura (2017) re-estimated the ages of 11 tsunami deposits in the last 4000 years along the Sanriku coast of northern Japan and found that the average <span class="hlt">recurrence</span> interval of those tsunamis as 350-390 years. Ramos et al. (2017) studied 1000-year-old marine terraces on the west coast of Luzon Island, Philippines</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70027839','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70027839"><span>Predecessors of the giant 1960 Chile <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Cisternas, M.; Atwater, B.F.; Torrejon, F.; Sawai, Y.; Machuca, G.; Lagos, M.; Eipert, A.; Youlton, C.; Salgado, I.; Kamataki, T.; Shishikura, M.; Rajendran, C.P.; Malik, J.K.; Rizal, Y.; Husni, M.</p> <p>2005-01-01</p> <p>It is commonly thought that the longer the time since last <span class="hlt">earthquake</span>, the larger the next <span class="hlt">earthquake</span>'s slip will be. But this logical predictor of <span class="hlt">earthquake</span> size, unsuccessful for large <span class="hlt">earthquakes</span> on a strike-slip fault, fails also with the giant 1960 Chile <span class="hlt">earthquake</span> of magnitude 9.5 (ref. 3). Although the time since the preceding <span class="hlt">earthquake</span> spanned 123 years (refs 4, 5), the estimated slip in 1960, which occurred on a fault between the Nazca and South American tectonic plates, equalled 250-350 years' worth of the plate motion. Thus the average interval between such giant <span class="hlt">earthquakes</span> on this fault should span several centuries. Here we present evidence that such long intervals were indeed typical of the last two millennia. We use buried soils and sand layers as records of tectonic subsidence and tsunami inundation at an estuary midway along the 1960 rupture. In these records, the 1960 <span class="hlt">earthquake</span> ended a <span class="hlt">recurrence</span> interval that had begun almost four centuries before, with an <span class="hlt">earthquake</span> documented by Spanish conquistadors in 1575. Two later <span class="hlt">earthquakes</span>, in 1737 and 1837, produced little if any subsidence or tsunami at the estuary and they therefore probably left the fault partly loaded with accumulated plate motion that the 1960 <span class="hlt">earthquake</span> then expended. ?? 2005 Nature Publishing Group.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16163355','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16163355"><span>Predecessors of the giant 1960 Chile <span class="hlt">earthquake</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cisternas, Marco; Atwater, Brian F; Torrejón, Fernando; Sawai, Yuki; Machuca, Gonzalo; Lagos, Marcelo; Eipert, Annaliese; Youlton, Cristián; Salgado, Ignacio; Kamataki, Takanobu; Shishikura, Masanobu; Rajendran, C P; Malik, Javed K; Rizal, Yan; Husni, Muhammad</p> <p>2005-09-15</p> <p>It is commonly thought that the longer the time since last <span class="hlt">earthquake</span>, the larger the next <span class="hlt">earthquake</span>'s slip will be. But this logical predictor of <span class="hlt">earthquake</span> size, unsuccessful for large <span class="hlt">earthquakes</span> on a strike-slip fault, fails also with the giant 1960 Chile <span class="hlt">earthquake</span> of magnitude 9.5 (ref. 3). Although the time since the preceding <span class="hlt">earthquake</span> spanned 123 years (refs 4, 5), the estimated slip in 1960, which occurred on a fault between the Nazca and South American tectonic plates, equalled 250-350 years' worth of the plate motion. Thus the average interval between such giant <span class="hlt">earthquakes</span> on this fault should span several centuries. Here we present evidence that such long intervals were indeed typical of the last two millennia. We use buried soils and sand layers as records of tectonic subsidence and tsunami inundation at an estuary midway along the 1960 rupture. In these records, the 1960 <span class="hlt">earthquake</span> ended a <span class="hlt">recurrence</span> interval that had begun almost four centuries before, with an <span class="hlt">earthquake</span> documented by Spanish conquistadors in 1575. Two later <span class="hlt">earthquakes</span>, in 1737 and 1837, produced little if any subsidence or tsunami at the estuary and they therefore probably left the fault partly loaded with accumulated plate motion that the 1960 <span class="hlt">earthquake</span> then expended.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25614068','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25614068"><span>Definitive radiotherapy for primary vaginal cancer: correlation between treatment patterns and <span class="hlt">recurrence</span> <span class="hlt">rate</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kanayama, Naoyuki; Isohashi, Fumiaki; Yoshioka, Yasuo; Baek, Sungjae; Chatani, Masashi; Kotsuma, Tadayuki; Tanaka, Eiichi; Yoshida, Ken; Seo, Yuji; Suzuki, Osamu; Mabuchi, Seiji; Shiki, Yasuhiko; Tatsumi, Keiji; Kimura, Tadashi; Teshima, Teruki; Ogawa, Kazuhiko</p> <p>2015-03-01</p> <p>The purpose of this study was to determine the outcomes and optimal practice patterns of definitive radiotherapy for primary vaginal cancer. Between 1993 and 2012, 49 patients were treated with definitive radiotherapy for primary vaginal cancer in three hospitals. Of these, 15 patients (31%) had clinically positive regional lymph node metastasis. A total of 34 patients (70%) received external beam radiotherapy with high-dose-<span class="hlt">rate</span> brachytherapy (interstitial or intracavitary), and 8 (16%) (with small superficial Stage I tumors) were treated with local radiotherapy. The median follow-up was 33 months (range: 1-169 months). The 3-year overall survival (OS), disease-free survival (DFS), and loco-regional control (LRC) <span class="hlt">rates</span> were 83%, 59% and 71%, respectively. In multivariate analysis, the histological type (P = 0.044) was significant risk factors for LRC. In Federation of Gynecology and Obstetrics (FIGO) Stage I cases, 3 of 8 patients (38%) who did not undergo prophylactic lymph node irradiation had lymph node <span class="hlt">recurrence</span>, compared with 2 of 12 patients (17%) who underwent prophylactic pelvic irradiation. For Stage III-IV tumors, the local <span class="hlt">recurrence</span> <span class="hlt">rate</span> was 50% and the lymph node <span class="hlt">recurrence</span> <span class="hlt">rate</span> was 40%. Patients with FIGO Stage I/II or clinical Stage N1 had a higher <span class="hlt">recurrence</span> <span class="hlt">rate</span> with treatment using a single modality compared with the <span class="hlt">recurrence</span> <span class="hlt">rate</span> using combined modalities. In conclusion, our treatment outcomes for vaginal cancer were acceptable, but external beam radiotherapy with brachytherapy (interstitial or intracavitary) was needed regardless of FIGO stage. Improvement of treatment outcomes in cases of FIGO Stage III or IV remains a significant challenge. © The Author 2015. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70024267','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70024267"><span>Paleoseismic event dating and the conditional probability of large <span class="hlt">earthquakes</span> on the southern San Andreas fault, California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Biasi, G.P.; Weldon, R.J.; Fumal, T.E.; Seitz, G.G.</p> <p>2002-01-01</p> <p>We introduce a quantitative approach to paleoearthquake dating and apply it to paleoseismic data from the Wrightwood and Pallett Creek sites on the southern San Andreas fault. We illustrate how stratigraphic ordering, sedimentological, and historical data can be used quantitatively in the process of estimating <span class="hlt">earthquake</span> ages. Calibrated radiocarbon age distributions are used directly from layer dating through <span class="hlt">recurrence</span> intervals and <span class="hlt">recurrence</span> probability estimation. The method does not eliminate subjective judgements in event dating, but it does provide a means of systematically and objectively approaching the dating process. Date distributions for the most recent 14 events at Wrightwood are based on sample and contextual evidence in Fumal et al. (2002) and site context and slip history in Weldon et al. (2002). Pallett Creek event and dating descriptions are from published sources. For the five most recent events at Wrightwood, our results are consistent with previously published estimates, with generally comparable or narrower uncertainties. For Pallett Creek, our <span class="hlt">earthquake</span> date estimates generally overlap with previous results but typically have broader uncertainties. Some event date estimates are very sensitive to details of data interpretation. The historical <span class="hlt">earthquake</span> in 1857 ruptured the ground at both sites but is not constrained by radiocarbon data. Radiocarbon ages, peat accumulation <span class="hlt">rates</span>, and historical constraints at Pallett Creek for event X yield a date estimate in the earliest 1800s and preclude a date in the late 1600s. This event is almost certainly the historical 1812 <span class="hlt">earthquake</span>, as previously concluded by Sieh et al. (1989). This <span class="hlt">earthquake</span> also produced ground deformation at Wrightwood. All events at Pallett Creek, except for event T, about A.D. 1360, and possibly event I, about A.D. 960, have corresponding events at Wrightwood with some overlap in age ranges. Event T falls during a period of low sedimentation at Wrightwood when conditions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.9104H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.9104H"><span>An <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecast for Europe based on smoothed seismicity and smoothed fault contribution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hiemer, Stefan; Woessner, Jochen; Basili, Roberto; Wiemer, Stefan</p> <p>2013-04-01</p> <p>The main objective of project SHARE (Seismic Hazard Harmonization in Europe) is to develop a community-based seismic hazard model for the Euro-Mediterranean region. The logic tree of <span class="hlt">earthquake</span> rupture forecasts comprises several methodologies including smoothed seismicity approaches. Smoothed seismicity thus represents an alternative concept to express the degree of spatial stationarity of seismicity and provides results that are more objective, reproducible, and testable. Nonetheless, the smoothed-seismicity approach suffers from the common drawback of being generally based on <span class="hlt">earthquake</span> catalogs alone, i.e. the wealth of knowledge from geology is completely ignored. We present a model that applies the kernel-smoothing method to both past <span class="hlt">earthquake</span> locations and slip <span class="hlt">rates</span> on mapped crustal faults and subductions. The result is mainly driven by the data, being independent of subjective delineation of seismic source zones. The core parts of our model are two distinct location probability densities: The first is computed by smoothing past seismicity (using variable kernel smoothing to account for varying data density). The second is obtained by smoothing fault moment <span class="hlt">rate</span> contributions. The fault moment <span class="hlt">rates</span> are calculated by summing the moment <span class="hlt">rate</span> of each fault patch on a fully parameterized and discretized fault as available from the SHARE fault database. We assume that the regional frequency-magnitude distribution of the entire study area is well known and estimate the a- and b-value of a truncated Gutenberg-Richter magnitude distribution based on a maximum likelihood approach that considers the spatial and temporal completeness history of the seismic catalog. The two location probability densities are linearly weighted as a function of magnitude assuming that (1) the occurrence of past seismicity is a good proxy to forecast occurrence of future seismicity and (2) future large-magnitude events occur more likely in the vicinity of known faults. Consequently</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.appliedgeologybook.com/','USGSPUBS'); return false;" href="http://www.appliedgeologybook.com/"><span><span class="hlt">Earthquake</span> geology and paleoseismology of major strands of the San Andreas fault system: Chapter 38</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Rockwell, Thomas; Scharer, Katherine M.; Dawson, Timothy E.</p> <p>2016-01-01</p> <p>The San Andreas fault system in California is one of the best-studied faults in the world, both in terms of the long-term geologic history and paleoseismic study of past surface ruptures. In this paper, we focus on the Quaternary to historic data that have been collected from the major strands of the San Andreas fault system, both on the San Andreas Fault itself, and the major subparallel strands that comprise the plate boundary, including the Calaveras-Hayward- Rogers Creek-Maacama fault zone and the Concord-Green Valley-Bartlett Springs fault zone in northern California, and the San Jacinto and Elsinore faults in southern California. The majority of the relative motion between the Pacific and North American lithospheric plates is accommodated by these faults, with the San Andreas slipping at about 34 mm/yr in central California, decreasing to about 20 mm/yr in northern California north of its juncture with the Calaveras and Concord faults. The Calaveras-Hayward-Rogers Creek-Maacama fault zone exhibits a slip <span class="hlt">rate</span> of 10-15 mm/yr, whereas the <span class="hlt">rate</span> along the Concord-Green Valley-Bartlett Springs fault zone is lower at about 5 mm/yr. In southern California, the San Andreas exhibits a slip <span class="hlt">rate</span> of about 35 mm/yr along the Mojave section, decreasing to as low as 10-15 mm/yr along its juncture with the San Jacinto fault, and about 20 mm/yr in the Coachella Valley. The San Jacinto and Elsinore fault zones exhibit <span class="hlt">rates</span> of about 15 and 5 mm/yr, respectively. The average <span class="hlt">recurrence</span> interval for surface-rupturing <span class="hlt">earthquakes</span> along individual elements of the San Andreas fault system range from 100-500 years and is consistent with slip <span class="hlt">rate</span> at those sites: higher slip <span class="hlt">rates</span> produce more frequent or larger <span class="hlt">earthquakes</span>. There is also evidence of short-term variations in strain release (slip <span class="hlt">rate</span>) along various fault sections, as expressed as “flurries” or clusters of <span class="hlt">earthquakes</span> as well as periods of relatively fewer surface ruptures in these relatively short records. This</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911903S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911903S"><span>Aseismic blocks and destructive <span class="hlt">earthquakes</span> in the Aegean</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stiros, Stathis</p> <p>2017-04-01</p> <p>Aseismic areas are not identified only in vast, geologically stable regions, but also within regions of active, intense, distributed deformation such as the Aegean. In the latter, "aseismic blocks" about 200m wide were recognized in the 1990's on the basis of the absence of instrumentally-derived <span class="hlt">earthquake</span> foci, in contrast to surrounding areas. This pattern was supported by the available historical seismicity data, as well as by geologic evidence. Interestingly, GPS evidence indicates that such blocks are among the areas characterized by small deformation <span class="hlt">rates</span> relatively to surrounding areas of higher deformation. Still, the largest and most destructive <span class="hlt">earthquake</span> of the 1990's, the 1995 M6.6 <span class="hlt">earthquake</span> occurred at the center of one of these "aseismic" zones at the northern part of Greece, found unprotected against seismic hazard. This case was indeed a repeat of the case of the tsunami-associated 1956 Amorgos Island M7.4 <span class="hlt">earthquake</span>, the largest 20th century event in the Aegean back-arc region: the 1956 <span class="hlt">earthquake</span> occurred at the center of a geologically distinct region (Cyclades Massif in Central Aegean), till then assumed aseismic. Interestingly, after 1956, the overall idea of aseismic regions remained valid, though a "promontory" of <span class="hlt">earthquake</span> prone-areas intruding into the aseismic central Aegean was assumed. Exploitation of the archaeological excavation evidence and careful, combined analysis of historical and archaeological data and other palaeoseismic, mostly coastal data, indicated that destructive and major <span class="hlt">earthquakes</span> have left their traces in previously assumed aseismic blocks. In the latter <span class="hlt">earthquakes</span> typically occur with relatively low <span class="hlt">recurrence</span> intervals, >200-300 years, much smaller than in adjacent active areas. Interestingly, areas assumed a-seismic in antiquity are among the most active in the last centuries, while areas hit by major <span class="hlt">earthquakes</span> in the past are usually classified as areas of low seismic risk in official maps. Some reasons</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUSMNH41A..02C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUSMNH41A..02C"><span>Complexity in Size, <span class="hlt">Recurrence</span> and Source of Historical <span class="hlt">Earthquakes</span> and Tsunamis in Central Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cisternas, M.</p> <p>2013-05-01</p> <p>Central Chile has a 470-year-long written <span class="hlt">earthquake</span> history, the longest of any part of the country. Thanks to the early and continuous Spanish settlement of this part of Chile (32°- 35° S), records document destructive <span class="hlt">earthquakes</span> and tsunamis in 1575, 1647, 1730, 1822, 1906 and 1985. This sequence has promoted the idea that central Chile's large subduction inter-plate <span class="hlt">earthquakes</span> recur at regular intervals of about 80 years. The last of these <span class="hlt">earthquakes</span>, in 1985, was even forecast as filling a seismic gap on the thrust boundary between the subducting Nazca Plate and the overriding South America Plate. Following this logic, the next large <span class="hlt">earthquake</span> in metropolitan Chile will not occur until late in the 21st century. However, here I challenge this conclusion by reporting recently discovered historical evidence in Spain, Japan, Peru, and Chile. This new evidence augments the historical catalog in central Chile, strongly suggests that one of these <span class="hlt">earthquakes</span> previously assumed to occur on the inter-plate interface in fact occurred elsewhere, and forces the conclusion that another of these <span class="hlt">earthquakes</span> (and its accompanying tsunami) dwarfed the others. These findings complicate the task of assessing the hazard of future <span class="hlt">earthquakes</span> in Chile's most populated region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27979023','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27979023"><span><span class="hlt">Rate</span> of <span class="hlt">recurrent</span> anaphylaxis and associated risk factors among Olmsted County, Minnesota, residents: A population-based study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Sangil; Bashore, Curtis; Lohse, Christine M; Bellolio, M Fernanda; Chamberlain, Alanna; Yuki, Kumi; Hess, Erik P; Campbell, Ronna L</p> <p>2016-12-01</p> <p>The <span class="hlt">rate</span> and risk factors for <span class="hlt">recurrence</span> of anaphylaxis are not well known. To measure the <span class="hlt">rate</span> and risk factors for <span class="hlt">recurrent</span> anaphylaxis in a population-based cohort in Olmsted County, Minnesota. We conducted a population-based cohort study using the Rochester Epidemiology Project, a comprehensive medical records linkage system, to obtain records of patients who presented to medical centers within the Olmsted County area with anaphylaxis from January 1, 2001, through December 31, 2010. We evaluated the <span class="hlt">rate</span> and associations of risk factors with anaphylaxis <span class="hlt">recurrence</span>. Among the 611 patients with anaphylaxis, 50 (8%) experienced a total of 60 <span class="hlt">recurrences</span> within the 10-year period, resulting in a <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 2.6 per 100 person-years. A history of atopic dermatitis (hazard ratio [HR], 5.6; 95% confidence interval [CI], 2.0-16.1; P = .001), presenting symptoms of cough (HR, 4.7; 95% CI, 2.1-10.7; P < .001) oral pruritus (HR, 9.9; 95% CI, 4.3-23.2; P < .001), and receiving corticosteroids (HR, 5.2; 95% CI, 2.3-11.7; P < .001) were associated with an increased risk of <span class="hlt">recurrence</span>. The cardiovascular symptom of chest pain (HR, 0.24; 95% CI, 0.07-0.79; P = .02) was associated with a decreased risk of <span class="hlt">recurrence</span>. In this epidemiologic study, the <span class="hlt">rate</span> of <span class="hlt">recurrence</span> was 8% during the 10-year study period (<span class="hlt">recurrence</span> <span class="hlt">rate</span> of 2.6 per 100 person-years). Those with atopic dermatitis and mucocutaneous or respiratory symptoms were more likely to have a <span class="hlt">recurrent</span> anaphylactic event. Our findings underscore the importance of early patient access to self-injectable epinephrine and referral to an allergist/immunologist for additional testing and education. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920055210&hterms=probability+statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dprobability%2Bstatistics','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920055210&hterms=probability+statistics&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dprobability%2Bstatistics"><span>An application of synthetic seismicity in <span class="hlt">earthquake</span> statistics - The Middle America Trench</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ward, Steven N.</p> <p>1992-01-01</p> <p>The way in which seismicity calculations which are based on the concept of fault segmentation incorporate the physics of faulting through static dislocation theory can improve <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> statistics and hone the probabilities of hazard is shown. For the Middle America Trench, the spread parameters of the best-fitting lognormal or Weibull distributions (about 0.75) are much larger than the 0.21 intrinsic spread proposed in the Nishenko Buland (1987) hypothesis. Stress interaction between fault segments disrupts time or slip predictability and causes <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> to be far more aperiodic than has been suggested.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18642208','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18642208"><span>[<span class="hlt">Recurrence</span> <span class="hlt">rate</span> following adjuvant strontium-90 brachytherapy after excision of conjunctival melanoma].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Krause, L; Ritter, C; Wachtlin, J; Kreusel, K-M; Höcht, S; Foerster, M H; Bechrakis, N E</p> <p>2008-07-01</p> <p>Because of the high local <span class="hlt">recurrence</span> <span class="hlt">rates</span> after excision of conjunctival melanomas, adjuvant local chemotherapy or irradiation is recommended. Strontium-90 brachytherapy is one radiotherapeutic option due to its low penetration depth. 15 patients with conjunctival melanoma were treated with adjuvant strontium-90 brachytherapy after tumour excision. The treatment was fractionated into 9 irradiation sessions with 6 Gy each. The mean follow-up was 35 months (12-60 months). Seven patients (46%) had no <span class="hlt">recurrence</span> during the follow-up. Three patients (20%) had a <span class="hlt">recurrence</span> in the treated or adjacent area. Eight patients (53%) developed new tumours in non-treated areas. Strontium-90 brachytherapy is a useful adjuvant in the treatment of conjunctival melanomas. Regular ophthalmoscopic controls are necessary because of the high <span class="hlt">rate</span> of new tumours in non-irradiated areas, especially in cases with primary acquired melanosis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EP%26S...68...40S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EP%26S...68...40S"><span>Fatality <span class="hlt">rates</span> of the M w ~8.2, 1934, Bihar-Nepal <span class="hlt">earthquake</span> and comparison with the April 2015 Gorkha <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sapkota, Soma Nath; Bollinger, Laurent; Perrier, Frédéric</p> <p>2016-03-01</p> <p>Large Himalayan <span class="hlt">earthquakes</span> expose rapidly growing populations of millions of people to high levels of seismic hazards, in particular in northeast India and Nepal. Calibrating vulnerability models specific to this region of the world is therefore crucial to the development of reliable mitigation measures. Here, we reevaluate the >15,700 casualties (8500 in Nepal and 7200 in India) from the M w ~8.2, 1934, Bihar-Nepal <span class="hlt">earthquake</span> and calculate the fatality <span class="hlt">rates</span> for this <span class="hlt">earthquake</span> using an estimation of the population derived from two census held in 1921 and 1942. Values reach 0.7-1 % in the epicentral region, located in eastern Nepal, and 2-5 % in the urban areas of the Kathmandu valley. Assuming a constant vulnerability, we obtain, if the same <span class="hlt">earthquake</span> would have repeated in 2011, fatalities of 33,000 in Nepal and 50,000 in India. Fast-growing population in India indeed must unavoidably lead to increased levels of casualty compared with Nepal, where the population growth is smaller. Aside from that probably robust fact, extrapolations have to be taken with great caution. Among other effects, building and life vulnerability could depend on population concentration and evolution of construction methods. Indeed, fatalities of the April 25, 2015, M w 7.8 Gorkha <span class="hlt">earthquake</span> indicated on average a reduction in building vulnerability in urban areas, while rural areas remained highly vulnerable. While effective scaling laws, function of the building stock, seem to describe these differences adequately, vulnerability in the case of an M w >8.2 <span class="hlt">earthquake</span> remains largely unknown. Further research should be carried out urgently so that better prevention strategies can be implemented and building codes reevaluated on, adequately combining detailed ancient and modern data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/7271755-new-madrid-seismic-zone-recurrence-intervals','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/7271755-new-madrid-seismic-zone-recurrence-intervals"><span>New Madrid seismic zone <span class="hlt">recurrence</span> intervals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Schweig, E.S.; Ellis, M.A.</p> <p>1993-03-01</p> <p>Frequency-magnitude relations in the New Madrid seismic zone suggest that great <span class="hlt">earthquakes</span> should occur every 700--1,200 yrs, implying relatively high strain <span class="hlt">rates</span>. These estimates are supported by some geological and GPS results. <span class="hlt">Recurrence</span> intervals of this order should have produced about 50 km of strike-slip offset since Miocene time. No subsurface evidence for such large displacements is known within the seismic zone. Moreover, the irregular fault pattern forming a compressive step that one sees today is not compatible with large displacements. There are at least three possible interpretations of the observations of short <span class="hlt">recurrence</span> intervals and high strain <span class="hlt">rates</span>, butmore » apparently youthful fault geometry and lack of major post-Miocene deformation. One is that the seismological and geodetic evidence are misleading. A second possibility is that activity in the region is cyclic. That is, the geological and geodetic observations that suggest relatively short <span class="hlt">recurrence</span> intervals reflect a time of high, but geologically temporary, pore-fluid pressure. Zoback and Zoback have suggested such a model for intraplate seismicity in general. Alternatively, the New Madrid seismic zone is geologically young feature that has been active for only the last few tens of thousands of years. In support of this, observe an irregular fault geometry associated with a unstable compressive step, a series of en echelon and discontinuous lineaments that may define the position of a youthful linking fault, and the general absence of significant post-Eocene faulting or topography.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70014341','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70014341"><span>Retardations in fault creep <span class="hlt">rates</span> before local moderate <span class="hlt">earthquakes</span> along the San Andreas fault system, central California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Burford, R.O.</p> <p>1988-01-01</p> <p>Records of shallow aseismic slip (fault creep) obtained along parts of the San Andreas and Calaveras faults in central California demonstrate that significant changes in creep <span class="hlt">rates</span> often have been associated with local moderate <span class="hlt">earthquakes</span>. An immediate postearthquake increase followed by gradual, long-term decay back to a previous background <span class="hlt">rate</span> is generally the most obvious <span class="hlt">earthquake</span> effect on fault creep. This phenomenon, identified as aseismic afterslip, usually is characterized by above-average creep <span class="hlt">rates</span> for several months to a few years. In several cases, minor step-like movements, called coseismic slip events, have occurred at or near the times of mainshocks. One extreme case of coseismic slip, recorded at Cienega Winery on the San Andreas fault 17.5 km southeast of San Juan Bautista, consisted of 11 mm of sudden displacement coincident with <span class="hlt">earthquakes</span> of ML=5.3 and ML=5.2 that occurred 2.5 minutes apart on 9 April 1961. At least one of these shocks originated on the main fault beneath the winery. Creep activity subsequently stopped at the winery for 19 months, then gradually returned to a nearly steady <span class="hlt">rate</span> slightly below the previous long-term average. The phenomena mentioned above can be explained in terms of simple models consisting of relatively weak material along shallow reaches of the fault responding to changes in load imposed by sudden slip within the underlying seismogenic zone. In addition to coseismic slip and afterslip phenomena, however, pre-<span class="hlt">earthquake</span> retardations in creep <span class="hlt">rates</span> also have been observed. Onsets of significant, persistent decreases in creep <span class="hlt">rates</span> have occurred at several sites 12 months or more before the times of moderate <span class="hlt">earthquakes</span>. A 44-month retardation before the 1979 ML=5.9 Coyote Lake <span class="hlt">earthquake</span> on the Calaveras fault was recorded at the Shore Road creepmeter site 10 km northwest of Hollister. Creep retardation on the San Andreas fault near San Juan Bautista has been evident in records from one creepmeter site for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988PApGe.126..499B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988PApGe.126..499B"><span>Retardations in fault creep <span class="hlt">rates</span> before local moderate <span class="hlt">earthquakes</span> along the San Andreas fault system, central California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Burford, Robert O.</p> <p>1988-06-01</p> <p>Records of shallow aseismic slip (fault creep) obtained along parts of the San Andreas and Calaveras faults in central California demonstrate that significant changes in creep <span class="hlt">rates</span> often have been associated with local moderate <span class="hlt">earthquakes</span>. An immediate postearthquake increase followed by gradual, long-term decay back to a previous background <span class="hlt">rate</span> is generally the most obvious <span class="hlt">earthquake</span> effect on fault creep. This phenomenon, identified as aseismic afterslip, usually is characterized by above-average creep <span class="hlt">rates</span> for several months to a few years. In several cases, minor step-like movements, called coseismic slip events, have occurred at or near the times of mainshocks. One extreme case of coseismic slip, recorded at Cienega Winery on the San Andreas fault 17.5 km southeast of San Juan Bautista, consisted of 11 mm of sudden displacement coincident with <span class="hlt">earthquakes</span> of M L =5.3 and M L =5.2 that occurred 2.5 minutes apart on 9 April 1961. At least one of these shocks originated on the main fault beneath the winery. Creep activity subsequently stopped at the winery for 19 months, then gradually returned to a nearly steady <span class="hlt">rate</span> slightly below the previous long-term average. The phenomena mentioned above can be explained in terms of simple models consisting of relatively weak material along shallow reaches of the fault responding to changes in load imposed by sudden slip within the underlying seismogenic zone. In addition to coseismic slip and afterslip phenomena, however, pre-<span class="hlt">earthquake</span> retardations in creep <span class="hlt">rates</span> also have been observed. Onsets of significant, persistent decreases in creep <span class="hlt">rates</span> have occurred at several sites 12 months or more before the times of moderate <span class="hlt">earthquakes</span>. A 44-month retardation before the 1979 M L =5.9 Coyote Lake <span class="hlt">earthquake</span> on the Calaveras fault was recorded at the Shore Road creepmeter site 10 km northwest of Hollister. Creep retardation on the San Andreas fault near San Juan Bautista has been evident in records from one creepmeter</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5426798','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5426798"><span>When do correlations increase with firing <span class="hlt">rates</span> in <span class="hlt">recurrent</span> networks?</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2017-01-01</p> <p>A central question in neuroscience is to understand how noisy firing patterns are used to transmit information. Because neural spiking is noisy, spiking patterns are often quantified via pairwise correlations, or the probability that two cells will spike coincidentally, above and beyond their baseline firing <span class="hlt">rate</span>. One observation frequently made in experiments, is that correlations can increase systematically with firing <span class="hlt">rate</span>. Theoretical studies have determined that stimulus-dependent correlations that increase with firing <span class="hlt">rate</span> can have beneficial effects on information coding; however, we still have an incomplete understanding of what circuit mechanisms do, or do not, produce this correlation-firing <span class="hlt">rate</span> relationship. Here, we studied the relationship between pairwise correlations and firing <span class="hlt">rates</span> in <span class="hlt">recurrently</span> coupled excitatory-inhibitory spiking networks with conductance-based synapses. We found that with stronger excitatory coupling, a positive relationship emerged between pairwise correlations and firing <span class="hlt">rates</span>. To explain these findings, we used linear response theory to predict the full correlation matrix and to decompose correlations in terms of graph motifs. We then used this decomposition to explain why covariation of correlations with firing rate—a relationship previously explained in feedforward networks driven by correlated input—emerges in some <span class="hlt">recurrent</span> networks but not in others. Furthermore, when correlations covary with firing <span class="hlt">rate</span>, this relationship is reflected in low-rank structure in the correlation matrix. PMID:28448499</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Tectp.733...73Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Tectp.733...73Y"><span>Modeling <span class="hlt">earthquake</span> sequences along the Manila subduction zone: Effects of three-dimensional fault geometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yu, Hongyu; Liu, Yajing; Yang, Hongfeng; Ning, Jieyuan</p> <p>2018-05-01</p> <p>To assess the potential of catastrophic megathrust <span class="hlt">earthquakes</span> (MW > 8) along the Manila Trench, the eastern boundary of the South China Sea, we incorporate a 3D non-planar fault geometry in the framework of <span class="hlt">rate</span>-state friction to simulate <span class="hlt">earthquake</span> rupture sequences along the fault segment between 15°N-19°N of northern Luzon. Our simulation results demonstrate that the first-order fault geometry heterogeneity, the transitional-segment (possibly related to the subducting Scarborough seamount chain) connecting the steeper south segment and the flatter north segment, controls <span class="hlt">earthquake</span> rupture behaviors. The strong along-strike curvature at the transitional-segment typically leads to partial ruptures of MW 8.3 and MW 7.8 along the southern and northern segments respectively. The entire fault occasionally ruptures in MW 8.8 events when the cumulative stress in the transitional-segment is sufficiently high to overcome the geometrical inhibition. Fault shear stress evolution, represented by the S-ratio, is clearly modulated by the width of seismogenic zone (W). At a constant plate convergence <span class="hlt">rate</span>, a larger W indicates on average lower interseismic stress loading <span class="hlt">rate</span> and longer rupture <span class="hlt">recurrence</span> period, and could slow down or sometimes stop ruptures that initiated from a narrower portion. Moreover, the modeled interseismic slip <span class="hlt">rate</span> before whole-fault rupture events is comparable with the coupling state that was inferred from the interplate seismicity distribution, suggesting the Manila trench could potentially rupture in a M8+ <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27286443','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27286443"><span>Physiological growth hormone replacement and <span class="hlt">rate</span> of <span class="hlt">recurrence</span> of craniopharyngioma: the Genentech National Cooperative Growth Study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Smith, Timothy R; Cote, David J; Jane, John A; Laws, Edward R</p> <p>2016-10-01</p> <p>OBJECTIVE The object of this study was to establish <span class="hlt">recurrence</span> <span class="hlt">rates</span> in patients with craniopharyngioma postoperatively treated with recombinant human growth hormone (rhGH) as a basis for determining the risk of rhGH therapy in the development of <span class="hlt">recurrent</span> tumor. METHODS The study included 739 pediatric patients with craniopharyngioma who were naïve to GH upon entering the Genentech National Cooperative Growth Study (NCGS) for treatment. Reoperation for tumor <span class="hlt">recurrence</span> was documented as an adverse event. Cox proportional-hazards regression models were developed for time to <span class="hlt">recurrence</span>, using age as the outcome and enrollment date as the predictor. Patients without <span class="hlt">recurrence</span> were treated as censored. Multivariate logistic regression was used to examine the incidence of <span class="hlt">recurrence</span> with adjustment for the amount of time at risk. RESULTS Fifty <span class="hlt">recurrences</span> in these 739 surgically treated patients were recorded. The overall craniopharyngioma <span class="hlt">recurrence</span> <span class="hlt">rate</span> in the NCGS was 6.8%, with a median follow-up time of 4.3 years (range 0.7-6.4 years.). Age at the time of study enrollment was statistically significant according to both Cox (p = 0.0032) and logistic (p < 0.001) models, with patients under 9 years of age more likely to suffer <span class="hlt">recurrence</span> (30 patients [11.8%], 0.025 <span class="hlt">recurrences</span>/yr of observation, p = 0.0097) than those ages 9-13 years (17 patients [6.0%], 0.17 <span class="hlt">recurrences</span>/yr of observation) and children older than 13 years (3 patients [1.5%], 0.005 <span class="hlt">recurrences</span>/yr of observation). CONCLUSIONS Physiological doses of GH do not appear to increase the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of craniopharyngioma after surgery in children, but long-term follow-up of GH-treated patients is required to establish a true natural history in the GH treatment era.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018Icar..303..273L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018Icar..303..273L"><span>Empirical <span class="hlt">recurrence</span> <span class="hlt">rates</span> for ground motion signals on planetary surfaces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lorenz, Ralph D.; Panning, Mark</p> <p>2018-03-01</p> <p>We determine the <span class="hlt">recurrence</span> <span class="hlt">rates</span> of ground motion events as a function of sensed velocity amplitude at several terrestrial locations, and make a first interplanetary comparison with measurements on the Moon, Mars, Venus and Titan. This empirical approach gives an intuitive order-of-magnitude guide to the observed ground motion (including both tectonic and ocean- and atmosphere-forced signals) of these locations as a guide to instrument expectations on future missions, without invoking interior models and specific sources: for example a Venera-14 observation of possible ground motion indicates a microseismic environment mid-way between noisy and quiet terrestrial locations. Quiet terrestrial regions see a peak velocity amplitude in mm/s roughly equal to 0.3*N(-0.7), where N is the number of "events" (half-hour intervals in which a given peak ground motion is exceeded) observed per year. The Apollo data show endogenous seismic signals for a given <span class="hlt">recurrence</span> <span class="hlt">rate</span> that are typically about 10,000 times smaller in amplitude than a quiet site on Earth, although local thermally-induced moonquakes are much more common. Viking data masked for low-wind periods appear comparable with a quiet terrestrial site, whereas a Venera observation of microseisms suggests ground motion more similar to a more active terrestrial location. <span class="hlt">Recurrence</span> <span class="hlt">rate</span> plots from in-situ measurements provide a context for seismic instrumentation on future planetary missions, e.g. to guide formulation of data compression schemes. While even small geophones can discriminate terrestrial activity <span class="hlt">rates</span>, observations with guidance accelerometers are typically too insensitive to provide meaningful constraints (i.e. a non-zero number of "events") on actual ground motion observations unless operated for very long periods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70001345','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70001345"><span><span class="hlt">Recurrence</span> of seismic migrations along the central California segment of the San Andreas fault system</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wood, M.D.; Allen, S.S.</p> <p>1973-01-01</p> <p>VERIFICATIONS of tectonic concepts1 concerning seafloor spreading are emerging in a manner that has direct bearing on <span class="hlt">earthquake</span> prediction. Although the gross pattern of worldwide seismicity contributed to the formulation of the plate tectonic hypothesis, it is the space-time characteristics of this seismicity that may contribute more toward understanding the kinematics and dynamics of the driving mechanism long speculated to originate in the mantle. If the lithosphere is composed of plates that move essentially as rigid bodies, then there should be seismic edge effects associated with this movement. It is these interplate effects, especially seismic migration patterns, that we discuss here. The unidirectional propagation at constant velocity (80 km yr-1 east to west) for <span class="hlt">earthquakes</span> (M???7.2) on the Antblian fault for the period 1939 to 1956 (ref. 2) is one of the earliest observations of such a phenomenon. Similar studies3,4 of the Alaska Aleutian seismic zone and certain regions of the west coast of South America suggest unidirectional and recurring migrations of <span class="hlt">earthquakes</span> (M???7.7) occur in these areas. Between these two regions along the great transform faults of the west coast of North America, there is some evidence 5 for unidirectional, constant velocity and <span class="hlt">recurrent</span> migration of great <span class="hlt">earthquakes</span>. The small population of <span class="hlt">earthquakes</span> (M>7.2) in Savage's investigation5 indicates a large spatial gap along the San Andreas system in central California from 1830 to 1970. Previous work on the seismicity of this gap in central California indicates that the <span class="hlt">recurrence</span> curves remain relatively constant, independent of large <span class="hlt">earthquakes</span>, for periods up to a century6. <span class="hlt">Recurrence</span> intervals for <span class="hlt">earthquakes</span> along the San Andreas Fault have been calculated empirically by Wallace7 on the basis of geological evidence, surface measurements and assumptions restricted to the surficial seismic layer. Here we examine the evidence for <span class="hlt">recurrence</span> of seismic migrations along</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22938804','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22938804"><span>Correction of contracture and <span class="hlt">recurrence</span> <span class="hlt">rates</span> of Dupuytren contracture following invasive treatment: the importance of clear definitions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Werker, Paul M N; Pess, Gary M; van Rijssen, Annet L; Denkler, Keith</p> <p>2012-10-01</p> <p>To call attention to the wide variety of definitions for <span class="hlt">recurrence</span> that have been employed in studies of different invasive procedures for the treatment of Dupuytren contracture and how this important limitation has contributed to the wide range of reported results. This study reviewed definitions and <span class="hlt">rates</span> of contracture correction and <span class="hlt">recurrence</span> in patients undergoing invasive treatment of Dupuytren contracture. A literature search was carried out in January 2011 using the terms "Dupuytren" AND ("fasciectomy" OR "fasciotomy" OR "dermofasciectomy" OR "aponeurotomy" OR "aponeurectomy") and limited to studies in English. The search returned 218 studies, of which 21 had definitions, quantitative results for contracture correction and <span class="hlt">recurrence</span>, and a sample size of at least 20 patients. Definitions for correction of contracture and <span class="hlt">recurrence</span> varied greatly among articles and were almost always qualitative. Percentages of patients who achieved correction of contracture (ie, responder <span class="hlt">rate</span>) when evaluated at various times after completion of surgery ranged from 15% to 96% for fasciectomy/aponeurectomy. Responder <span class="hlt">rates</span> were not reported for fasciotomy/aponeurotomy. <span class="hlt">Recurrence</span> <span class="hlt">rates</span> ranged from 12% to 73% for patients treated with fasciectomy/aponeurectomy and from 33% to 100% for fasciotomy/aponeurotomy. Review of these reports underscored the difficulty involved in comparing correction of contracture and <span class="hlt">recurrence</span> <span class="hlt">rates</span> for different surgical interventions because of differences in definition and duration of follow-up. Clearly defined objective definitions for correction of contracture and for <span class="hlt">recurrence</span> are needed for more meaningful comparisons of results achieved with different surgical interventions. <span class="hlt">Recurrence</span> after surgical intervention for Dupuytren contracture is common. This study, which evaluated reported <span class="hlt">rates</span> of <span class="hlt">recurrence</span> following surgical treatment of Dupuytren contracture, provides clinicians with practical information regarding expected long</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29643366','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29643366"><span>Constant strain accumulation <span class="hlt">rate</span> between major <span class="hlt">earthquakes</span> on the North Anatolian Fault.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hussain, Ekbal; Wright, Tim J; Walters, Richard J; Bekaert, David P S; Lloyd, Ryan; Hooper, Andrew</p> <p>2018-04-11</p> <p><span class="hlt">Earthquakes</span> are caused by the release of tectonic strain accumulated between events. Recent advances in satellite geodesy mean we can now measure this interseismic strain accumulation with a high degree of accuracy. But it remains unclear how to interpret short-term geodetic observations, measured over decades, when estimating the seismic hazard of faults accumulating strain over centuries. Here, we show that strain accumulation <span class="hlt">rates</span> calculated from geodetic measurements around a major transform fault are constant for its entire 250-year interseismic period, except in the ~10 years following an <span class="hlt">earthquake</span>. The shear strain <span class="hlt">rate</span> history requires a weak fault zone embedded within a strong lower crust with viscosity greater than ~10 20  Pa s. The results support the notion that short-term geodetic observations can directly contribute to long-term seismic hazard assessment and suggest that lower-crustal viscosities derived from postseismic studies are not representative of the lower crust at all spatial and temporal scales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189777','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189777"><span>Late Holocene slip <span class="hlt">rate</span> and ages of prehistoric <span class="hlt">earthquakes</span> along the Maacama Fault near Willits, Mendocino County, northern California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Prentice, Carol S.; Larsen, Martin C.; Kelsey, Harvey M.; Zachariasen, Judith</p> <p>2014-01-01</p> <p>The Maacama fault is the northward continuation of the Hayward–Rodgers Creek fault system and creeps at a <span class="hlt">rate</span> of 5.7±0.1  mm/yr (averaged over the last 20 years) in Willits, California. Our paleoseismic studies at Haehl Creek suggest that the Maacama fault has produced infrequent large <span class="hlt">earthquakes</span> in addition to creep. Fault terminations observed in several excavations provide evidence that a prehistoric surface‐rupturing <span class="hlt">earthquake</span> occurred between 1060 and 1180 calibrated years (cal) B.P. at the Haehl Creek site. A folding event, which we attribute to a more recent large <span class="hlt">earthquake</span>, occurred between 790 and 1060 cal B.P. In the last 560–690 years, a buried channel deposit has been offset 4.6±0.2  m, giving an average slip <span class="hlt">rate</span> of 6.4–8.6  mm/yr, which is higher than the creep <span class="hlt">rate</span> over the last 20 years. The difference between this slip <span class="hlt">rate</span> and the creep <span class="hlt">rate</span> suggests that coseismic slip up to 1.7 m could have occurred after the formation of the channel deposit and could be due to a paleoearthquake known from paleoseismic studies in the Ukiah Valley, about 25 km to the southeast. Therefore, we infer that at least two, and possibly three, large <span class="hlt">earthquakes</span> have occurred at the Haehl Creek site since 1180 cal B.P. (770 C.E.), consistent with earlier studies suggesting infrequent, large <span class="hlt">earthquakes</span> on the Maacama fault. The short‐term geodetic slip <span class="hlt">rate</span> across the Maacama fault zone is approximately twice the slip <span class="hlt">rate</span> that we have documented at the Haehl Creek site, which is averaged over the last approximately 600 years. If the geodetic <span class="hlt">rate</span> represents the long‐term slip accumulation across the fault zone, then we infer that, in the last ∼1200 years, additional <span class="hlt">earthquakes</span> may have occurred either on the Haehl Creek segment of the Maacama fault or on other active faults within the Maacama fault zone at this latitude.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21372172-high-dose-rate-intraoperative-radiation-therapy-recurrent-head-neck-cancer','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21372172-high-dose-rate-intraoperative-radiation-therapy-recurrent-head-neck-cancer"><span>High-Dose-<span class="hlt">Rate</span> Intraoperative Radiation Therapy for <span class="hlt">Recurrent</span> Head-and-Neck Cancer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Perry, David J.; Chan, Kelvin; Wolden, Suzanne</p> <p>2010-03-15</p> <p>Purpose: To report the use of high-dose-<span class="hlt">rate</span> intraoperative radiation therapy (HDR-IORT) for <span class="hlt">recurrent</span> head-and-neck cancer (HNC) at a single institution. Methods and Materials: Between July 1998 and February 2007, 34 patients with <span class="hlt">recurrent</span> HNC received 38 HDR-IORT treatments using a Harrison-Anderson-Mick applicator with Iridium-192. A single fraction (median, 15 Gy; range, 10-20 Gy) was delivered intraoperatively after surgical resection to the region considered at risk for close or positive margins. In all patients, the target region was previously treated with external beam radiation therapy (median dose, 63 Gy; range, 24-74 Gy). The 1- and 2-year estimates for in-field local progression-freemore » survival (LPFS), locoregional progression-free survival (LRPFS), distant metastases-free survival (DMFS), and overall survival (OS) were calculated. Results: With a median follow-up for surviving patients of 23 months (range, 6-54 months), 8 patients (24%) are alive and without evidence of disease. The 1- and 2-year LPFS <span class="hlt">rates</span> are 66% and 56%, respectively, with 13 (34%) in-field <span class="hlt">recurrences</span>. The 1- and 2-year DMFS <span class="hlt">rates</span> are 81% and 62%, respectively, with 10 patients (29%) developing distant failure. The 1- and 2-year OS <span class="hlt">rates</span> are 73% and 55%, respectively, with a median time to OS of 24 months. Severe complications included cellulitis (5 patients), fistula or wound complications (3 patients), osteoradionecrosis (1 patient), and radiation-induced trigeminal neuralgia (1 patient). Conclusions: HDR-IORT has shown encouraging local control outcomes in patients with <span class="hlt">recurrent</span> HNC with acceptable <span class="hlt">rates</span> of treatment-related morbidity. Longer follow-up with a larger cohort of patients is needed to fully assess the benefit of this procedure.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.S21A2146L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S21A2146L"><span>The Active Fault Parameters for Time-Dependent <span class="hlt">Earthquake</span> Hazard Assessment in Taiwan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Y.; Cheng, C.; Lin, P.; Shao, K.; Wu, Y.; Shih, C.</p> <p>2011-12-01</p> <p>Taiwan is located at the boundary between the Philippine Sea Plate and the Eurasian Plate, with a convergence <span class="hlt">rate</span> of ~ 80 mm/yr in a ~N118E direction. The plate motion is so active that <span class="hlt">earthquake</span> is very frequent. In the Taiwan area, disaster-inducing <span class="hlt">earthquakes</span> often result from active faults. For this reason, it's an important subject to understand the activity and hazard of active faults. The active faults in Taiwan are mainly located in the Western Foothills and the Eastern longitudinal valley. Active fault distribution map published by the Central Geological Survey (CGS) in 2010 shows that there are 31 active faults in the island of Taiwan and some of which are related to <span class="hlt">earthquake</span>. Many researchers have investigated these active faults and continuously update new data and results, but few people have integrated them for time-dependent <span class="hlt">earthquake</span> hazard assessment. In this study, we want to gather previous researches and field work results and then integrate these data as an active fault parameters table for time-dependent <span class="hlt">earthquake</span> hazard assessment. We are going to gather the seismic profiles or <span class="hlt">earthquake</span> relocation of a fault and then combine the fault trace on land to establish the 3D fault geometry model in GIS system. We collect the researches of fault source scaling in Taiwan and estimate the maximum magnitude from fault length or fault area. We use the characteristic <span class="hlt">earthquake</span> model to evaluate the active fault <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> interval. In the other parameters, we will collect previous studies or historical references and complete our parameter table of active faults in Taiwan. The WG08 have done the time-dependent <span class="hlt">earthquake</span> hazard assessment of active faults in California. They established the fault models, deformation models, <span class="hlt">earthquake</span> <span class="hlt">rate</span> models, and probability models and then compute the probability of faults in California. Following these steps, we have the preliminary evaluated probability of <span class="hlt">earthquake</span>-related hazards in certain</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24943955','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24943955"><span>Possible control of subduction zone slow-<span class="hlt">earthquake</span> periodicity by silica enrichment.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Audet, Pascal; Bürgmann, Roland</p> <p>2014-06-19</p> <p>Seismic and geodetic observations in subduction zone forearcs indicate that slow <span class="hlt">earthquakes</span>, including episodic tremor and slip, recur at intervals of less than six months to more than two years. In Cascadia, slow slip is segmented along strike and tremor data show a gradation from large, infrequent slip episodes to small, frequent slip events with increasing depth of the plate interface. Observations and models of slow slip and tremor require the presence of near-lithostatic pore-fluid pressures in slow-<span class="hlt">earthquake</span> source regions; however, direct evidence of factors controlling the variability in <span class="hlt">recurrence</span> times is elusive. Here we compile seismic data from subduction zone forearcs exhibiting recurring slow <span class="hlt">earthquakes</span> and show that the average ratio of compressional (P)-wave velocity to shear (S)-wave velocity (vP/vS) of the overlying forearc crust ranges between 1.6 and 2.0 and is linearly related to the average <span class="hlt">recurrence</span> time of slow <span class="hlt">earthquakes</span>. In northern Cascadia, forearc vP/vS values decrease with increasing depth of the plate interface and with decreasing tremor-episode <span class="hlt">recurrence</span> intervals. Low vP/vS values require a large addition of quartz in a mostly mafic forearc environment. We propose that silica enrichment varying from 5 per cent to 15 per cent by volume from slab-derived fluids and upward mineralization in quartz veins can explain the range of observed vP/vS values as well as the downdip decrease in vP/vS. The solubility of silica depends on temperature, and deposition prevails near the base of the forearc crust. We further propose that the strong temperature dependence of healing and permeability reduction in silica-rich fault gouge via dissolution-precipitation creep can explain the reduction in tremor <span class="hlt">recurrence</span> time with progressive silica enrichment. Lower gouge permeability at higher temperatures leads to faster fluid overpressure development and low effective fault-normal stress, and therefore shorter <span class="hlt">recurrence</span> times. Our results also</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.9867G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.9867G"><span>The Rurrand Fault, Germany: A Holocene surface rupture and new slip <span class="hlt">rate</span> estimates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Grützner, Christoph; Fischer, Peter; Reicherter, Klaus</p> <p>2016-04-01</p> <p>Very low deformation <span class="hlt">rates</span> in continental interiors are a challenge for research on active tectonics and seismic hazard. Faults tend to have very long <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals and morphological evidence of surface faulting is often obliterated by erosion and sedimentation. The Lower Rhine Graben in Central Europe is characterized by slow active faults with individual slip <span class="hlt">rates</span> of well less than 0.1 mm/a. As a consequence, most geodetic techniques fail to record tectonic motions and the morphological expression of the faults is subtle. Although damaging events are known from this region, e.g. the 1755/56 Düren <span class="hlt">earthquakes</span> series, there is no account for surface rupturing events in instrumental and historical records. Owing to the short temporal coverage with respect to the fault <span class="hlt">recurrence</span> intervals, these records probably fail to depict the maximum possible magnitudes. In this study we used morphological evidence from a 1 m airborne LiDAR survey, near surface geophysics, and paleoseismological trenching to identify surface rupturing <span class="hlt">earthquakes</span> at the Rurrand Fault between Cologne and Aachen in W Germany. LiDAR data allowed identifying a young fault strand parallel to the already known main fault with the subtle morphological expression of recent surface faulting. In the paleoseismological trenches we found evidence for two surface rupturing <span class="hlt">earthquakes</span>. The most recent event occurred in the Holocene, and a previous <span class="hlt">earthquake</span> probably happened in the last 150 ka. Geophysical data allowed us to estimate a minimum slip <span class="hlt">rate</span> of 0.03 mm/a from an offset gravel horizon. We estimate paleomagnitudes of MW5.9-6.8 based on the observed offsets in the trench (<0.5 m per event) and fault scaling relationships. Our data imply that the Rurrand Fault did not creep during the last 150 ka, but rather failed in large <span class="hlt">earthquakes</span>. These events were much stronger than those known from historical sources. We are able to show that the Rurrand Fault did not rupture the surface</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007NPGeo..14..455A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007NPGeo..14..455A"><span><span class="hlt">Recurrence</span> and interoccurrence behavior of self-organized complex phenomena</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abaimov, S. G.; Turcotte, D. L.; Shcherbakov, R.; Rundle, J. B.</p> <p>2007-08-01</p> <p>The sandpile, forest-fire and slider-block models are said to exhibit self-organized criticality. Associated natural phenomena include landslides, wildfires, and <span class="hlt">earthquakes</span>. In all cases the frequency-size distributions are well approximated by power laws (fractals). Another important aspect of both the models and natural phenomena is the statistics of interval times. These statistics are particularly important for <span class="hlt">earthquakes</span>. For <span class="hlt">earthquakes</span> it is important to make a distinction between interoccurrence and <span class="hlt">recurrence</span> times. Interoccurrence times are the interval times between <span class="hlt">earthquakes</span> on all faults in a region whereas <span class="hlt">recurrence</span> times are interval times between <span class="hlt">earthquakes</span> on a single fault or fault segment. In many, but not all cases, interoccurrence time statistics are exponential (Poissonian) and the events occur randomly. However, the distribution of <span class="hlt">recurrence</span> times are often Weibull to a good approximation. In this paper we study the interval statistics of slip events using a slider-block model. The behavior of this model is sensitive to the stiffness α of the system, α=kC/kL where kC is the spring constant of the connector springs and kL is the spring constant of the loader plate springs. For a soft system (small α) there are no system-wide events and interoccurrence time statistics of the larger events are Poissonian. For a stiff system (large α), system-wide events dominate the energy dissipation and the statistics of the <span class="hlt">recurrence</span> times between these system-wide events satisfy the Weibull distribution to a good approximation. We argue that this applicability of the Weibull distribution is due to the power-law (scale invariant) behavior of the hazard function, i.e. the probability that the next event will occur at a time t0 after the last event has a power-law dependence on t0. The Weibull distribution is the only distribution that has a scale invariant hazard function. We further show that the onset of system-wide events is a well defined</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.464...35C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.464...35C"><span>Seismicity <span class="hlt">rate</span> increases associated with slow slip episodes prior to the 2012 Mw 7.4 Ometepec <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Colella, Harmony V.; Sit, Stefany M.; Brudzinski, Michael R.; Graham, Shannon E.; DeMets, Charles; Holtkamp, Stephen G.; Skoumal, Robert J.; Ghouse, Noorulann; Cabral-Cano, Enrique; Kostoglodov, Vladimir; Arciniega-Ceballos, Alejandra</p> <p>2017-04-01</p> <p>The March 20, 2012 Mw 7.4 Ometepec <span class="hlt">earthquake</span> in the Oaxaca region of Southern Mexico provides a unique opportunity to examine whether subtle changes in seismicity, tectonic tremor, or slow slip can be observed prior to a large <span class="hlt">earthquake</span> that may illuminate changes in stress or background slip <span class="hlt">rate</span>. Continuous Global Positioning System (cGPS) data reveal a 5-month-long slow slip event (SSE) between ∼20 and 35 km depth that migrated toward and reached the vicinity of the mainshock a few weeks prior to the <span class="hlt">earthquake</span>. Seismicity in Oaxaca is examined using single station tectonic tremor detection and multi-station waveform template matching of <span class="hlt">earthquake</span> families. An increase in seismic activity, detected with template matching using aftershock waveforms, is only observed in the weeks prior to the mainshock in the region between the SSE and mainshock. In contrast, a SSE ∼15 months earlier occurred at ∼25-40 km depth and was primarily associated with an increase in tectonic tremor. Together, these observations indicate that in the Oaxaca region of Mexico shallower slow slip promotes elevated seismicity <span class="hlt">rates</span>, and deeper slow slip promotes tectonic tremor. Results from this study add to a growing number of published accounts that indicate slow slip may be a common pre-<span class="hlt">earthquake</span> signature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70191351','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70191351"><span>Evaluating spatial and temporal relationships between an <span class="hlt">earthquake</span> cluster near Entiat, central Washington, and the large December 1872 Entiat <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brocher, Thomas M.; Blakely, Richard J.; Sherrod, Brian</p> <p>2017-01-01</p> <p>We investigate spatial and temporal relations between an ongoing and prolific seismicity cluster in central Washington, near Entiat, and the 14 December 1872 Entiat <span class="hlt">earthquake</span>, the largest historic crustal <span class="hlt">earthquake</span> in Washington. A fault scarp produced by the 1872 <span class="hlt">earthquake</span> lies within the Entiat cluster; the locations and areas of both the cluster and the estimated 1872 rupture surface are comparable. Seismic intensities and the 1–2 m of coseismic displacement suggest a magnitude range between 6.5 and 7.0 for the 1872 <span class="hlt">earthquake</span>. Aftershock forecast models for (1) the first several hours following the 1872 <span class="hlt">earthquake</span>, (2) the largest felt <span class="hlt">earthquakes</span> from 1900 to 1974, and (3) the seismicity within the Entiat cluster from 1976 through 2016 are also consistent with this magnitude range. Based on this aftershock modeling, most of the current seismicity in the Entiat cluster could represent aftershocks of the 1872 <span class="hlt">earthquake</span>. Other <span class="hlt">earthquakes</span>, especially those with long <span class="hlt">recurrence</span> intervals, have long‐lived aftershock sequences, including the Mw">MwMw 7.5 1891 Nobi <span class="hlt">earthquake</span> in Japan, with aftershocks continuing 100 yrs after the mainshock. Although we do not rule out ongoing tectonic deformation in this region, a long‐lived aftershock sequence can account for these observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRB..122.5417C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRB..122.5417C"><span>Temporal variation of tectonic tremor activity in southern Taiwan around the 2010 ML6.4 Jiashian <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chao, Kevin; Peng, Zhigang; Hsu, Ya-Ju; Obara, Kazushige; Wu, Chunquan; Ching, Kuo-En; van der Lee, Suzan; Pu, Hsin-Chieh; Leu, Peih-Lin; Wech, Aaron</p> <p>2017-07-01</p> <p>Deep tectonic tremor, which is extremely sensitive to small stress variations, could be used to monitor fault zone processes during large <span class="hlt">earthquake</span> cycles and aseismic processes before large <span class="hlt">earthquakes</span>. In this study, we develop an algorithm for the automatic detection and location of tectonic tremor beneath the southern Central Range of Taiwan and examine the spatiotemporal relationship between tremor and the 4 March 2010 ML6.4 Jiashian <span class="hlt">earthquake</span>, located about 20 km from active tremor sources. We find that tremor in this region has a relatively short duration, short <span class="hlt">recurrence</span> time, and no consistent correlation with surface GPS data. We find a short-term increase in the tremor <span class="hlt">rate</span> 19 days before the Jiashian main shock, and around the time when the tremor <span class="hlt">rate</span> began to rise one GPS station recorded a flip in its direction of motion. We hypothesize that tremor is driven by a slow-slip event that preceded the occurrence of the shallower Jiashian main shock, even though the inferred slip is too small to be observed by all GPS stations. Our study shows that tectonic tremor may reflect stress variation during the prenucleation process of a nearby <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRB..118.5699B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRB..118.5699B"><span>Active accommodation of plate convergence in Southern Iran: <span class="hlt">Earthquake</span> locations, triggered aseismic slip, and regional strain <span class="hlt">rates</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Barnhart, William D.; Lohman, Rowena B.; Mellors, Robert J.</p> <p>2013-10-01</p> <p>We present a catalog of interferometric synthetic aperture radar (InSAR) constraints on deformation that occurred during <span class="hlt">earthquake</span> sequences in southern Iran between 1992 and 2011, and explore the implications on the accommodation of large-scale continental convergence between Saudi Arabia and Eurasia within the Zagros Mountains. The Zagros Mountains, a salt-laden fold-and-thrust belt involving ~10 km of sedimentary rocks overlying Precambrian basement rocks, have formed as a result of ongoing continental collision since 10-20 Ma that is currently occurring at a <span class="hlt">rate</span> of ~3 cm/yr. We first demonstrate that there is a biased misfit in <span class="hlt">earthquake</span> locations in global catalogs that likely results from neglect of 3-D velocity structure. Previous work involving two M ~ 6 <span class="hlt">earthquakes</span> with well-recorded aftershocks has shown that the deformation observed with InSAR may represent triggered slip on faults much shallower than the primary <span class="hlt">earthquake</span>, which likely occurred within the basement rocks (>10 km depth). We explore the hypothesis that most of the deformation observed with InSAR spanning <span class="hlt">earthquake</span> sequences is also due to shallow, triggered slip above a deeper <span class="hlt">earthquake</span>, effectively doubling the moment release for each event. We quantify the effects that this extra moment release would have on the discrepancy between seismically and geodetically constrained moment <span class="hlt">rates</span> in the region, finding that even with the extra triggered fault slip, significant aseismic deformation during the interseismic period is necessary to fully explain the convergence between Eurasia and Saudi Arabia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatGe...9..834I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatGe...9..834I"><span><span class="hlt">Earthquake</span> potential revealed by tidal influence on <span class="hlt">earthquake</span> size-frequency statistics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ide, Satoshi; Yabe, Suguru; Tanaka, Yoshiyuki</p> <p>2016-11-01</p> <p>The possibility that tidal stress can trigger <span class="hlt">earthquakes</span> is long debated. In particular, a clear causal relationship between small <span class="hlt">earthquakes</span> and the phase of tidal stress is elusive. However, tectonic tremors deep within subduction zones are highly sensitive to tidal stress levels, with tremor <span class="hlt">rate</span> increasing at an exponential <span class="hlt">rate</span> with rising tidal stress. Thus, slow deformation and the possibility of <span class="hlt">earthquakes</span> at subduction plate boundaries may be enhanced during periods of large tidal stress. Here we calculate the tidal stress history, and specifically the amplitude of tidal stress, on a fault plane in the two weeks before large <span class="hlt">earthquakes</span> globally, based on data from the global, Japanese, and Californian <span class="hlt">earthquake</span> catalogues. We find that very large <span class="hlt">earthquakes</span>, including the 2004 Sumatran, 2010 Maule <span class="hlt">earthquake</span> in Chile and the 2011 Tohoku-Oki <span class="hlt">earthquake</span> in Japan, tend to occur near the time of maximum tidal stress amplitude. This tendency is not obvious for small <span class="hlt">earthquakes</span>. However, we also find that the fraction of large <span class="hlt">earthquakes</span> increases (the b-value of the Gutenberg-Richter relation decreases) as the amplitude of tidal shear stress increases. The relationship is also reasonable, considering the well-known relationship between stress and the b-value. This suggests that the probability of a tiny rock failure expanding to a gigantic rupture increases with increasing tidal stress levels. We conclude that large <span class="hlt">earthquakes</span> are more probable during periods of high tidal stress.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JGRB..120..290K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JGRB..120..290K"><span>Nanoseismicity and picoseismicity <span class="hlt">rate</span> changes from static stress triggering caused by a Mw 2.2 <span class="hlt">earthquake</span> in Mponeng gold mine, South Africa</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kozłowska, Maria; Orlecka-Sikora, Beata; Kwiatek, Grzegorz; Boettcher, Margaret S.; Dresen, Georg</p> <p>2015-01-01</p> <p>Static stress changes following large <span class="hlt">earthquakes</span> are known to affect the <span class="hlt">rate</span> and distribution of aftershocks, yet this process has not been thoroughly investigated for nanoseismicity and picoseismicity at centimeter length scales. Here we utilize a unique data set of M ≥ -3.4 <span class="hlt">earthquakes</span> following a Mw 2.2 <span class="hlt">earthquake</span> in Mponeng gold mine, South Africa, that was recorded during a quiet interval in the mine to investigate if <span class="hlt">rate</span>- and state-based modeling is valid for shallow, mining-induced seismicity. We use Dieterich's (1994) <span class="hlt">rate</span>- and state-dependent formulation for <span class="hlt">earthquake</span> productivity, which requires estimation of four parameters: (1) Coulomb stress changes due to the main shock, (2) the reference seismicity <span class="hlt">rate</span>, (3) frictional resistance parameter, and (4) the duration of aftershock relaxation time. Comparisons of the modeled spatiotemporal patterns of seismicity based on two different source models with the observed distribution show that while the spatial patterns match well, the <span class="hlt">rate</span> of modeled aftershocks is lower than the observed <span class="hlt">rate</span>. To test our model, we used three metrics of the goodness-of-fit evaluation. The null hypothesis, of no significant difference between modeled and observed seismicity <span class="hlt">rates</span>, was only rejected in the depth interval containing the main shock. Results show that mining-induced <span class="hlt">earthquakes</span> may be followed by a stress relaxation expressed through aftershocks located on the rupture plane and in regions of positive Coulomb stress change. Furthermore, we demonstrate that the main features of the temporal and spatial distributions of very small, mining-induced <span class="hlt">earthquakes</span> can be successfully determined using <span class="hlt">rate</span>- and state-based stress modeling.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMOS11A1180K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMOS11A1180K"><span>Dense Ocean Floor Network for <span class="hlt">Earthquakes</span> and Tsunamis; DONET/ DONET2, Part2 -Development and data application for the mega thrust <span class="hlt">earthquakes</span> around the Nankai trough-</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaneda, Y.; Kawaguchi, K.; Araki, E.; Matsumoto, H.; Nakamura, T.; Nakano, M.; Kamiya, S.; Ariyoshi, K.; Baba, T.; Ohori, M.; Hori, T.; Takahashi, N.; Kaneko, S.; Donet Research; Development Group</p> <p>2010-12-01</p> <p>Yoshiyuki Kaneda Katsuyoshi Kawaguchi*, Eiichiro Araki*, Shou Kaneko*, Hiroyuki Matsumoto*, Takeshi Nakamura*, Masaru Nakano*, Shinichirou Kamiya*, Keisuke Ariyoshi*, Toshitaka Baba*, Michihiro Ohori*, Narumi Takakahashi*, and Takane Hori** * <span class="hlt">Earthquake</span> and Tsunami Research Project for Disaster Prevention, Leading Project , Japan Agency for Marine-Earth Science and Technology (JAMSTEC) **Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology (JAMSTEC) DONET (Dense Ocean Floor Network for <span class="hlt">Earthquakes</span> and Tsunamis) is the real time monitoring system of the Tonankai seismogenic zones around the Nankai trough southwestern Japan. We were starting to develop DONET to perform real time monitoring of crustal activities over there and the advanced early warning system. DONET will provide important and useful data to understand the Nankai trough maga thrust <span class="hlt">earthquake</span> seismogenic zones and to improve the accuracy of the <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> cycle simulation. Details of DONET concept are as follows. 1) Redundancy, Extendable function and advanced maintenance system using the looped cable system, junction boxes and the ROV/AUV. DONET has 20 observatories and incorporated in a double land stations concept. Also, we are developed ROV for the 10km cable extensions and heavy weight operations. 2) Multi kinds of sensors to observe broad band phenomena such as long period tremors, very low frequency <span class="hlt">earthquakes</span> and strong motions of mega thrust <span class="hlt">earthquakes</span> over M8: Therefore, sensors such as a broadband seismometer, an accelerometer, a hydrophone, a precise pressure gauge, a differential pressure gauge and a thermometer are equipped with each observatory in DONET. 3) For speedy detections, evaluations and notifications of <span class="hlt">earthquakes</span> and tsunamis: DONET system will be deployed around the Tonankai seismogenic zone. 4) Provide data of ocean floor crustal deformations derived from pressure sensors: Simultaneously, the development of data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.464..175C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.464..175C"><span>A plate boundary <span class="hlt">earthquake</span> record from a wetland adjacent to the Alpine fault in New Zealand refines hazard estimates</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cochran, U. A.; Clark, K. J.; Howarth, J. D.; Biasi, G. P.; Langridge, R. M.; Villamor, P.; Berryman, K. R.; Vandergoes, M. J.</p> <p>2017-04-01</p> <p>Discovery and investigation of millennial-scale geological records of past large <span class="hlt">earthquakes</span> improve understanding of <span class="hlt">earthquake</span> frequency, <span class="hlt">recurrence</span> behaviour, and likelihood of future rupture of major active faults. Here we present a ∼2000 year-long, seven-event <span class="hlt">earthquake</span> record from John O'Groats wetland adjacent to the Alpine fault in New Zealand, one of the most active strike-slip faults in the world. We linked this record with the 7000 year-long, 22-event <span class="hlt">earthquake</span> record from Hokuri Creek (20 km along strike to the north) to refine estimates of <span class="hlt">earthquake</span> frequency and <span class="hlt">recurrence</span> behaviour for the South Westland section of the plate boundary fault. Eight cores from John O'Groats wetland revealed a sequence that alternated between organic-dominated and clastic-dominated sediment packages. Transitions from a thick organic unit to a thick clastic unit that were sharp, involved a significant change in depositional environment, and were basin-wide, were interpreted as evidence of past surface-rupturing <span class="hlt">earthquakes</span>. Radiocarbon dates of short-lived organic fractions either side of these transitions were modelled to provide estimates for <span class="hlt">earthquake</span> ages. Of the seven events recognised at the John O'Groats site, three post-date the most recent event at Hokuri Creek, two match events at Hokuri Creek, and two events at John O'Groats occurred in a long interval during which the Hokuri Creek site may not have been recording <span class="hlt">earthquakes</span> clearly. The preferred John O'Groats-Hokuri Creek <span class="hlt">earthquake</span> record consists of 27 events since ∼6000 BC for which we calculate a mean <span class="hlt">recurrence</span> interval of 291 ± 23 years, shorter than previously estimated for the South Westland section of the fault and shorter than the current interseismic period. The revised 50-year conditional probability of a surface-rupturing <span class="hlt">earthquake</span> on this fault section is 29%. The coefficient of variation is estimated at 0.41. We suggest the low <span class="hlt">recurrence</span> variability is likely to be a feature of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70155520','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70155520"><span><span class="hlt">Earthquake</span> shaking hazard estimates and exposure changes in the conterminous United States</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jaiswal, Kishor S.; Petersen, Mark D.; Rukstales, Kenneth S.; Leith, William S.</p> <p>2015-01-01</p> <p>A large portion of the population of the United States lives in areas vulnerable to <span class="hlt">earthquake</span> hazards. This investigation aims to quantify population and infrastructure exposure within the conterminous U.S. that are subjected to varying levels of <span class="hlt">earthquake</span> ground motions by systematically analyzing the last four cycles of the U.S. Geological Survey's (USGS) National Seismic Hazard Models (published in 1996, 2002, 2008 and 2014). Using the 2013 LandScan data, we estimate the numbers of people who are exposed to potentially damaging ground motions (peak ground accelerations at or above 0.1g). At least 28 million (~9% of the total population) may experience 0.1g level of shaking at relatively frequent intervals (annual <span class="hlt">rate</span> of 1 in 72 years or 50% probability of exceedance (PE) in 50 years), 57 million (~18% of the total population) may experience this level of shaking at moderately frequent intervals (annual <span class="hlt">rate</span> of 1 in 475 years or 10% PE in 50 years), and 143 million (~46% of the total population) may experience such shaking at relatively infrequent intervals (annual <span class="hlt">rate</span> of 1 in 2,475 years or 2% PE in 50 years). We also show that there is a significant number of critical infrastructure facilities located in high <span class="hlt">earthquake</span>-hazard areas (Modified Mercalli Intensity ≥ VII with moderately frequent <span class="hlt">recurrence</span> interval).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S33A2754M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S33A2754M"><span>Evidence of Multiple Ground-rupturing <span class="hlt">Earthquakes</span> in the Past 4000 Years along the Pasuruan Fault, East Java, Indonesia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marliyani, G. I.; Arrowsmith, R.; Helmi, H.</p> <p>2015-12-01</p> <p>Instrumental and historical records of <span class="hlt">earthquakes</span>, supplemented by paleoeseismic constraints can help reveal the <span class="hlt">earthquake</span> potential of an area. The Pasuruan fault is a high angle normal fault with prominent youthful scarps cutting young deltaic sediments in the north coast of East Java, Indonesia and may pose significant hazard to the densely populated region. This fault has not been considered a significant structure, and mapped as a lineament with no sense of motion. Information regarding past <span class="hlt">earthquakes</span> along this fault is not available. The fault is well defined both in the imagery and in the field as a ~13km long, 2-50m-high scarp. Open and filled fractures and natural exposures of the south-dipping fault plane indicate normal sense of motion. We excavated two fault-perpendicular trenches across a relay ramp identified during our surface mapping. Evidence for past <span class="hlt">earthquakes</span> (documented in both trenches) includes upward fault termination with associated fissure fills, colluvial wedges and scarp-derived debris, folding, and angular unconformities. The ages of the events are constrained by 23 radiocarbon dates on detrital charcoal. We calibrated the dates using IntCal13 and used Oxcal to build the age model of the events. Our preliminary age model indicates that since 2006±134 B.C., there has been at least five ground rupturing <span class="hlt">earthquakes</span> along the fault. The oldest event identified in the trench however, is not well-dated. Our modeled 95th percentile ranges of the next four earlier <span class="hlt">earthquakes</span> (and their mean) are A.D. 1762-1850 (1806), A.D. 1646-1770 (1708), A.D. 1078-1648 (1363), and A.D. 726-1092 (909), yielding a rough <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 302±63 yrs. These new data imply that Pasuruan fault is more active than previously thought. Additional well-dated <span class="hlt">earthquakes</span> are necessary to build a solid <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> model. Rupture along the whole section implies a minimum <span class="hlt">earthquake</span> magnitude of 6.3, considering 13km as the minimum surface rupture</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://dx.doi.org/10.1785/0120110102','USGSPUBS'); return false;" href="http://dx.doi.org/10.1785/0120110102"><span>Integration of paleoseismic data from multiple sites to develop an objective <span class="hlt">earthquake</span> chronology: Application to the Weber segment of the Wasatch fault zone, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>DuRoss, Christopher B.; Personius, Stephen F.; Crone, Anthony J.; Olig, Susan S.; Lund, William R.</p> <p>2011-01-01</p> <p>We present a method to evaluate and integrate paleoseismic data from multiple sites into a single, objective measure of <span class="hlt">earthquake</span> timing and <span class="hlt">recurrence</span> on discrete segments of active faults. We apply this method to the Weber segment (WS) of the Wasatch fault zone using data from four fault-trench studies completed between 1981 and 2009. After systematically reevaluating the stratigraphic and chronologic data from each trench site, we constructed time-stratigraphic OxCal models that yield site probability density functions (PDFs) of the times of individual <span class="hlt">earthquakes</span>. We next qualitatively correlated the site PDFs into a segment-wide <span class="hlt">earthquake</span> chronology, which is supported by overlapping site PDFs, large per-event displacements, and prominent segment boundaries. For each segment-wide <span class="hlt">earthquake</span>, we computed the product of the site PDF probabilities in common time bins, which emphasizes the overlap in the site <span class="hlt">earthquake</span> times, and gives more weight to the narrowest, best-defined PDFs. The product method yields smaller <span class="hlt">earthquake</span>-timing uncertainties compared to taking the mean of the site PDFs, but is best suited to <span class="hlt">earthquakes</span> constrained by broad, overlapping site PDFs. We calculated segment-wide <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals and uncertainties using a Monte Carlo model. Five surface-faulting <span class="hlt">earthquakes</span> occurred on the WS at about 5.9, 4.5, 3.1, 1.1, and 0.6 ka. With the exception of the 1.1-ka event, we used the product method to define the <span class="hlt">earthquake</span> times. The revised WS chronology yields a mean <span class="hlt">recurrence</span> interval of 1.3 kyr (0.7–1.9-kyr estimated two-sigma [2δ] range based on interevent <span class="hlt">recurrence</span>). These data help clarify the paleoearthquake history of the WS, including the important question of the timing and rupture extent of the most recent <span class="hlt">earthquake</span>, and are essential to the improvement of <span class="hlt">earthquake</span>-probability assessments for the Wasatch Front region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70032226','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70032226"><span>Integration of paleoseismic data from multiple sites to develop an objective <span class="hlt">earthquake</span> chronology: Application to the Weber segment of the Wasatch fault zone, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>DuRoss, C.B.; Personius, S.F.; Crone, A.J.; Olig, S.S.; Lund, W.R.</p> <p>2011-01-01</p> <p>We present a method to evaluate and integrate paleoseismic data from multiple sites into a single, objective measure of <span class="hlt">earthquake</span> timing and <span class="hlt">recurrence</span> on discrete segments of active faults. We apply this method to the Weber segment (WS) of the Wasatch fault zone using data from four fault-trench studies completed between 1981 and 2009. After systematically reevaluating the stratigraphic and chronologic data from each trench site, we constructed time-stratigraphic OxCal models that yield site probability density functions (PDFs) of the times of individual <span class="hlt">earthquakes</span>. We next qualitatively correlated the site PDFs into a segment-wide <span class="hlt">earthquake</span> chronology, which is supported by overlapping site PDFs, large per-event displacements, and prominent segment boundaries. For each segment-wide <span class="hlt">earthquake</span>, we computed the product of the site PDF probabilities in common time bins, which emphasizes the overlap in the site <span class="hlt">earthquake</span> times, and gives more weight to the narrowest, best-defined PDFs. The product method yields smaller <span class="hlt">earthquake</span>-timing uncertainties compared to taking the mean of the site PDFs, but is best suited to <span class="hlt">earthquakes</span> constrained by broad, overlapping site PDFs. We calculated segment-wide <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals and uncertainties using a Monte Carlo model. Five surface-faulting <span class="hlt">earthquakes</span> occurred on the WS at about 5.9, 4.5, 3.1, 1.1, and 0.6 ka. With the exception of the 1.1-ka event, we used the product method to define the <span class="hlt">earthquake</span> times. The revised WS chronology yields a mean <span class="hlt">recurrence</span> interval of 1.3 kyr (0.7-1.9-kyr estimated two-sigma [2??] range based on interevent <span class="hlt">recurrence</span>). These data help clarify the paleoearthquake history of the WS, including the important question of the timing and rupture extent of the most recent <span class="hlt">earthquake</span>, and are essential to the improvement of <span class="hlt">earthquake</span>-probability assessments for the Wasatch Front region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.212.1627R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.212.1627R"><span>Surface rupture of the 1933 M 7.5 Diexi <span class="hlt">earthquake</span> in eastern Tibet: implications for seismogenic tectonics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ren, Junjie; Xu, Xiwei; Zhang, Shimin; Yeats, Robert S.; Chen, Jiawei; Zhu, Ailan; Liu, Shao</p> <p>2018-03-01</p> <p>The 1933 M 7.5 Diexi <span class="hlt">earthquake</span> is another catastrophic event with the loss of over 10 000 lives in eastern Tibet comparable to the 2008 Mw 7.9 Wenchuan <span class="hlt">earthquake</span>. Because of its unknown surface rupture, the seismogenic tectonics of the 1933 <span class="hlt">earthquake</span> remains controversial. We collected unpublished reports, literatures and old photos associated with the 1933 <span class="hlt">earthquake</span> and conducted field investigations based on high-resolution Google Earth imagery. Combined with palaeoseismological analysis, radiocarbon dating and relocated <span class="hlt">earthquakes</span>, our results demonstrate that the source of the 1933 <span class="hlt">earthquake</span> is the northwest-trending Songpinggou fault. This quake produced a > 30 km long normal-faulting surface rupture with the coseismic offset of 0.9-1.7 m. Its moment magnitude (Mw) is ˜6.8. The Songpinggou fault undergoes an average vertical slip <span class="hlt">rate</span> of ˜0.25 mm yr-1 and has a <span class="hlt">recurrence</span> interval of ˜6700 yr of large <span class="hlt">earthquakes</span>. The normal-faulting surface rupture of this quake is probably the reactivation of the Mesozoic Jiaochang tectonic belt in gravitational adjustment of eastern Tibet. Besides the major boundary faults, minor structures within continental blocks may take a role in strain partitioning of eastern Tibet and have the potential of producing large <span class="hlt">earthquake</span>. This study contributes to a full understanding of seismotectonics of large <span class="hlt">earthquakes</span> and strain partitioning in eastern Tibet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.T12A..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.T12A..01R"><span>On the feedback between forearc morphotectonics and megathrust <span class="hlt">earthquakes</span> in subduction zones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosenau, M.; Oncken, O.</p> <p>2008-12-01</p> <p>An increasing number of observations suggest an intrinsic relationship between short- and long-term deformation processes in subduction zones. These include the global correlation between megathrust <span class="hlt">earthquake</span> slip patterns with morphotectonic forearc features, the historical predominance of giant <span class="hlt">earthquakes</span> (M > 9) along accretionary margins and the occurrence of (slow and shallow) tsunami <span class="hlt">earthquakes</span> along erosive margins. To gain insight into the interplay between seismogenesis and tectonics in subduction settings we have developed a new modeling technique which joins analog and elastic dislocation approaches. Using elastoplastic wedges overlying a <span class="hlt">rate</span>- and state-dependent interface, we demonstrate how analog <span class="hlt">earthquakes</span> drive permanent wedge deformation consistent with the dynamic Coulomb wedge theory and how wedge deformation in turn controls basal "seismicity". During an experimental run, elastoplastic wedges evolve from those comparable to accretionary margins, characterized by plastic wedge shortening, to those mimicking erosive margins, characterized by minor plastic deformation. Permanent shortening localizes at the periphery of the "seismogenic" zone leading to a "morphotectonic" segmentation of the upper plate. Along with the evolving segmentation of the wedge, the magnitude- frequency relationship and <span class="hlt">recurrence</span> distribution of analog <span class="hlt">earthquakes</span> develop towards more periodic events of similar size (i.e. characteristic <span class="hlt">earthquakes</span>). From the experiments we infer a positive feedback between short- and long-term deformation processes which tends to stabilize the spatiotemporal patterns of elastoplastic deformation in subduction settings. We suggest (1) that forearc anatomy reflects the distribution of seismic and aseismic slip at depth, (2) that morphotectonic segmentation assists the occurrence of more characteristic <span class="hlt">earthquakes</span>, (3) that postseismic near-trench shortening relaxes coseismic compression by megathrust <span class="hlt">earthquakes</span> and thus reduces</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFMPA24A..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFMPA24A..03B"><span>Urban <span class="hlt">Earthquakes</span> - Reducing Building Collapse Through Education</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bilham, R.</p> <p>2004-12-01</p> <p>Fatalities from <span class="hlt">earthquakes</span> rose from 6000k to 9000k/year in the past decade, yet the ratio of numbers of <span class="hlt">earthquake</span> fatalities to instantaneous population continues to fall. Since 1950 the ratio declined worldwide by a factor of three, but in some countries the ratio has changed little. E.g in Iran, 1 in 3000 people can expect to die in an <span class="hlt">earthquake</span>, a percentage that has not changed significantly since 1890. Fatalities from <span class="hlt">earthquakes</span> remain high in those countries that have traditionally suffered from frequent large <span class="hlt">earthquakes</span> (Turkey, Iran, Japan, and China), suggesting that the exposure time of recently increased urban populations in other countries may be too short to have interacted with <span class="hlt">earthquakes</span> with long <span class="hlt">recurrence</span> intervals. This in turn, suggests that disasters of unprecendented size will occur (more than 1 million fatalities) when future large <span class="hlt">earthquakes</span> occur close to megacities. However, population growth is most rapid in cities of less than 1 million people in the developing nations, where the financial ability to implement <span class="hlt">earthquake</span> resistant construction methods is limited. In that structural collapse can often be traced to ignorance about the forces at work in an <span class="hlt">earthquake</span>, the future collapse of buildings presently under construction could be much reduced were contractors, builders and occupants educated in the principles of <span class="hlt">earthquake</span> resistant assembly. Education of builders who are tempted to cut assembly costs is likely to be more cost effective than material aid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17576069','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17576069"><span>Long-term <span class="hlt">recurrence</span> <span class="hlt">rate</span> of pleomorphic adenoma and postoperative facial nerve paresis (in parotid surgery).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zernial, Oliver; Springer, Ingo N; Warnke, Patrick; Härle, Franz; Risick, Christian; Wiltfang, Jörg</p> <p>2007-04-01</p> <p>The purpose of this study was to evaluate <span class="hlt">recurrence</span> <span class="hlt">rates</span> and comorbidity in patients with pleomorphic adenomas of patients after superficial and total conservative parotidectomy. Localization of pleomorphic adenomas, age, sex distribution and facial nerve function of 73 patients were examined in this retrospective study. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> could be determined in 43 of these patients. The interval between surgery and last recall varied between 2 and 20 years (median: 8.1 years). Most of the patients were female (67%) with a parotid pleomorphic adenoma. No <span class="hlt">recurrence</span> was found regard less of whether a superficial or total conservative parotidectomy had been performed. Our data did show that the total conservative parotidectomy is associated with a higher incidence of temporary impaired facial nerve function, which was seen in 42% of this group. Temporary decreased nerve function after superficial parotidectomy was rare being apparent in only 16% of this group. A more radical procedure does not significantly lower the <span class="hlt">recurrence</span> <span class="hlt">rate</span>. We suggest that the indication for a total conservative parotidectomy in cases of superficial adenomas should be considered carefully.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRA..122.2973B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRA..122.2973B"><span>Substorm occurrence <span class="hlt">rates</span>, substorm <span class="hlt">recurrence</span> times, and solar wind structure</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borovsky, Joseph E.; Yakymenko, Kateryna</p> <p>2017-03-01</p> <p>Two collections of substorms are created: 28,464 substorms identified with jumps in the SuperMAG AL index in the years 1979-2015 and 16,025 substorms identified with electron injections into geosynchronous orbit in the years 1989-2007. Substorm occurrence <span class="hlt">rates</span> and substorm <span class="hlt">recurrence</span>-time distributions are examined as functions of the phase of the solar cycle, the season of the year, the Russell-McPherron favorability, the type of solar wind plasma at Earth, the geomagnetic-activity level, and as functions of various solar and solar wind properties. Three populations of substorm occurrences are seen: (1) quasiperiodically occurring substorms with <span class="hlt">recurrence</span> times (waiting times) of 2-4 h, (2) randomly occurring substorms with <span class="hlt">recurrence</span> times of about 6-15 h, and (3) long intervals wherein no substorms occur. A working model is suggested wherein (1) the period of periodic substorms is set by the magnetosphere with variations in the actual <span class="hlt">recurrence</span> times caused by the need for a solar wind driving interval to occur, (2) the mesoscale structure of the solar wind magnetic field triggers the occurrence of the random substorms, and (3) the large-scale structure of the solar wind plasma is responsible for the long intervals wherein no substorms occur. Statistically, the <span class="hlt">recurrence</span> period of periodically occurring substorms is slightly shorter when the ram pressure of the solar wind is high, when the magnetic field strength of the solar wind is strong, when the Mach number of the solar wind is low, and when the polar-cap potential saturation parameter is high.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2006/1020/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2006/1020/"><span>Sensitivity of <span class="hlt">Earthquake</span> Loss Estimates to Source Modeling Assumptions and Uncertainty</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Reasenberg, Paul A.; Shostak, Nan; Terwilliger, Sharon</p> <p>2006-01-01</p> <p>Introduction: This report explores how uncertainty in an <span class="hlt">earthquake</span> source model may affect estimates of <span class="hlt">earthquake</span> economic loss. Specifically, it focuses on the <span class="hlt">earthquake</span> source model for the San Francisco Bay region (SFBR) created by the Working Group on California <span class="hlt">Earthquake</span> Probabilities. The loss calculations are made using HAZUS-MH, a publicly available computer program developed by the Federal Emergency Management Agency (FEMA) for calculating future losses from <span class="hlt">earthquakes</span>, floods and hurricanes within the United States. The database built into HAZUS-MH includes a detailed building inventory, population data, data on transportation corridors, bridges, utility lifelines, etc. <span class="hlt">Earthquake</span> hazard in the loss calculations is based upon expected (median value) ground motion maps called ShakeMaps calculated for the scenario <span class="hlt">earthquake</span> sources defined in WGCEP. The study considers the effect of relaxing certain assumptions in the WG02 model, and explores the effect of hypothetical reductions in epistemic uncertainty in parts of the model. For example, it addresses questions such as what would happen to the calculated loss distribution if the uncertainty in slip <span class="hlt">rate</span> in the WG02 model were reduced (say, by obtaining additional geologic data)? What would happen if the geometry or amount of aseismic slip (creep) on the region's faults were better known? And what would be the effect on the calculated loss distribution if the time-dependent <span class="hlt">earthquake</span> probability were better constrained, either by eliminating certain probability models or by better constraining the inherent randomness in <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>? The study does not consider the effect of reducing uncertainty in the hazard introduced through models of attenuation and local site characteristics, although these may have a comparable or greater effect than does source-related uncertainty. Nor does it consider sources of uncertainty in the building inventory, building fragility curves, and other assumptions</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70027442','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70027442"><span><span class="hlt">Earthquake</span> nucleation by transient deformations caused by the M = 7.9 Denali, Alaska, <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gomberg, J.; Bodin, P.; Larson, K.; Dragert, H.</p> <p>2004-01-01</p> <p>The permanent and dynamic (transient) stress changes inferred to trigger <span class="hlt">earthquakes</span> are usually orders of magnitude smaller than the stresses relaxed by the <span class="hlt">earthquakes</span> themselves, implying that triggering occurs on critically stressed faults. Triggered seismicity <span class="hlt">rate</span> increases may therefore be most likely to occur in areas where loading <span class="hlt">rates</span> are highest and elevated pore pressures, perhaps facilitated by high-temperature fluids, reduce frictional stresses and promote failure. Here we show that the 2002 magnitude M = 7.9 Denali, Alaska, <span class="hlt">earthquake</span> triggered wide-spread seismicity <span class="hlt">rate</span> increases throughout British Columbia and into the western United States. Dynamic triggering by seismic waves should be enhanced in directions where rupture directivity focuses radiated energy, and we verify this using seismic and new high-sample GPS recordings of the Denali mainshock. These observations are comparable in scale only to the triggering caused by the 1992 M = 7.4 Landers, California, <span class="hlt">earthquake</span>, and demonstrate that Landers triggering did not reflect some peculiarity of the region or the <span class="hlt">earthquake</span>. However, the <span class="hlt">rate</span> increases triggered by the Denali <span class="hlt">earthquake</span> occurred in areas not obviously tectonically active, implying that even in areas of low ambient stressing <span class="hlt">rates</span>, faults may still be critically stressed and that dynamic triggering may be ubiquitous and unpredictable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70023299','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70023299"><span><span class="hlt">Earthquake</span> triggering by seismic waves following the landers and hector mine <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gomberg, J.; Reasenberg, P.A.; Bodin, P.; Harris, R.A.</p> <p>2001-01-01</p> <p>The proximity and similarity of the 1992, magnitude 7.3 Landers and 1999, magnitude 7.1 Hector Mine <span class="hlt">earthquakes</span> in California permit testing of <span class="hlt">earthquake</span> triggering hypotheses not previously possible. The Hector Mine <span class="hlt">earthquake</span> confirmed inferences that transient, oscillatory 'dynamic' deformations radiated as seismic waves can trigger seismicity <span class="hlt">rate</span> increases, as proposed for the Landers <span class="hlt">earthquake</span>1-6. Here we quantify the spatial and temporal patterns of the seismicity <span class="hlt">rate</span> changes7. The seismicity <span class="hlt">rate</span> increase was to the north for the Landers <span class="hlt">earthquake</span> and primarily to the south for the Hector Mine <span class="hlt">earthquake</span>. We suggest that rupture directivity results in elevated dynamic deformations north and south of the Landers and Hector Mine faults, respectively, as evident in the asymmetry of the recorded seismic velocity fields. Both dynamic and static stress changes seem important for triggering in the near field with dynamic stress changes dominating at greater distances. Peak seismic velocities recorded for each <span class="hlt">earthquake</span> suggest the existence of, and place bounds on, dynamic triggering thresholds. These thresholds vary from a few tenths to a few MPa in most places, depend on local conditions, and exceed inferred static thresholds by more than an order of magnitude. At some sites, the onset of triggering was delayed until after the dynamic deformations subsided. Physical mechanisms consistent with all these observations may be similar to those that give rise to liquefaction or cyclic fatigue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.8573G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.8573G"><span>Late Holocene megathrust <span class="hlt">earthquakes</span> in south central Chile</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garrett, Ed; Shennan, Ian; Gulliver, Pauline; Woodroffe, Sarah</p> <p>2013-04-01</p> <p>A lack of comprehensive understanding of the seismic hazards associated with a subduction zone can lead to inadequate anticipation of <span class="hlt">earthquake</span> and tsunami magnitudes. Four hundred and fifty years of Chilean historical documents record the effects of numerous great <span class="hlt">earthquakes</span>; however, with <span class="hlt">recurrence</span> intervals between the largest megathrust <span class="hlt">earthquakes</span> approaching 300 years, seismic hazard assessment requires longer chronologies. This research seeks to verify and extend historical records in south central Chile using a relative-sea level approach to palaeoseismology. Our quantitative, diatom-based approaches to relative sea-level reconstruction are successful in reconstructing the magnitude of coseismic deformation during recent, well documented Chilean <span class="hlt">earthquakes</span>. The few disparities between my estimates and independent data highlight the possibility of shaking-induced sediment consolidation in tidal marshes. Following this encouraging confirmation of the approach, we quantify land-level changes in longer sedimentary records from the centre of the rupture zone of the 1960 Valdivia <span class="hlt">earthquake</span>. Here, laterally extensive marsh soils abruptly overlain by low intertidal sediments attest to the occurrence of four megathrust <span class="hlt">earthquakes</span>. Sites preserve evidence of the 1960 and 1575 <span class="hlt">earthquakes</span> and we constrain the timing of two predecessors to 1270 to 1410 and 1050 to 1200. The sediments and biostratigraphy lack evidence for the historically documented 1737 and 1837 <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22224406-local-recurrence-after-uveal-melanoma-proton-beam-therapy-recurrence-types-prognostic-consequences','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22224406-local-recurrence-after-uveal-melanoma-proton-beam-therapy-recurrence-types-prognostic-consequences"><span>Local <span class="hlt">Recurrence</span> After Uveal Melanoma Proton Beam Therapy: <span class="hlt">Recurrence</span> Types and Prognostic Consequences</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Caujolle, Jean-Pierre, E-mail: ncaujolle@aol.com; Paoli, Vincent; Chamorey, Emmanuel</p> <p></p> <p>Purpose: To study the prognosis of the different types of uveal melanoma <span class="hlt">recurrences</span> treated by proton beam therapy (PBT). Methods and Materials: This retrospective study analyzed 61 cases of uveal melanoma local <span class="hlt">recurrences</span> on a total of 1102 patients treated by PBT between June 1991 and December 2010. Survival <span class="hlt">rates</span> have been determined by using Kaplan-Meier curves. Prognostic factors have been evaluated by using log-rank test or Cox model. Results: Our local <span class="hlt">recurrence</span> <span class="hlt">rate</span> was 6.1% at 5 years. These <span class="hlt">recurrences</span> were divided into 25 patients with marginal <span class="hlt">recurrences</span>, 18 global <span class="hlt">recurrences</span>, 12 distant <span class="hlt">recurrences</span>, and 6 extrascleral extensions. Fivemore » factors have been identified as statistically significant risk factors of local <span class="hlt">recurrence</span> in the univariate analysis: large tumoral diameter, small tumoral volume, low ratio of tumoral volume over eyeball volume, iris root involvement, and safety margin inferior to 1 mm. In the local <span class="hlt">recurrence</span>-free population, the overall survival <span class="hlt">rate</span> was 68.7% at 10 years and the specific survival <span class="hlt">rate</span> was 83.6% at 10 years. In the local <span class="hlt">recurrence</span> population, the overall survival <span class="hlt">rate</span> was 43.1% at 10 years and the specific survival <span class="hlt">rate</span> was 55% at 10 years. The multivariate analysis of death risk factors has shown a better prognosis for marginal <span class="hlt">recurrences</span>. Conclusion: Survival <span class="hlt">rate</span> of marginal <span class="hlt">recurrences</span> is superior to that of the other <span class="hlt">recurrences</span>. The type of <span class="hlt">recurrence</span> is a clinical prognostic value to take into account. The influence of local <span class="hlt">recurrence</span> retreatment by proton beam therapy should be evaluated by novel studies.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20068358','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20068358"><span>Geographic variation in one-year <span class="hlt">recurrent</span> ischemic stroke <span class="hlt">rates</span> for elderly Medicare beneficiaries in the USA.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Allen, Norrina B; Holford, Theodore R; Bracken, Michael B; Goldstein, Larry B; Howard, George; Wang, Yun; Lichtman, Judith H</p> <p>2010-01-01</p> <p>While geographic disparities in stroke mortality are well documented, there are no data describing geographic variation in <span class="hlt">recurrent</span> stroke. Accordingly, we evaluated geographic variations in 1-year <span class="hlt">recurrent</span> ischemic stroke <span class="hlt">rates</span> in the USA with adjustment for patient characteristics. One-year <span class="hlt">recurrent</span> stroke <span class="hlt">rates</span> for ischemic stroke (International Classification of Diseases, 9th Revision codes 433, 434 and 436) following hospital discharge were calculated by county for all fee-for-service Medicare beneficiaries from 2000 to 2002. The <span class="hlt">rates</span> were standardized and smoothed using a bayesian conditional autoregressive model that was risk-standardized for patients' age, gender, race/ethnicity, prior hospitalizations, Deyo comorbidity score, acute myocardial infarction, congestive heart failure, diabetes, hypertension, dementia, cancer, chronic obstructive pulmonary disease and obesity. The overall 1-year <span class="hlt">recurrent</span> stroke <span class="hlt">rate</span> was 9.4% among 895,916 ischemic stroke patients (mean age: 78 years; 56.6% women; 86.6% White, 9.7% Black and 1.2% Latino/Hispanic). The <span class="hlt">rates</span> varied by geographic region and were highest in the South and in parts of the West and Midwest. Regional variation was present for all racial/ethnic subgroups and persisted after adjustment for individual patient characteristics. Almost 1 in 10 hospitalized ischemic stroke patients was readmitted for an ischemic stroke within 1 year. There was heterogeneity in <span class="hlt">recurrence</span> patterns by geographic region. Further work is needed to understand the reasons for this regional variability. Copyright 2010 S. Karger AG, Basel.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018ApJ...860..110S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018ApJ...860..110S"><span>The Masses and Accretion <span class="hlt">Rates</span> of White Dwarfs in Classical and <span class="hlt">Recurrent</span> Novae</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shara, Michael M.; Prialnik, Dina; Hillman, Yael; Kovetz, Attay</p> <p>2018-06-01</p> <p>Models have long predicted that the frequency-averaged masses of white dwarfs (WDs) in Galactic classical novae are twice as large as those of field WDs. Only a handful of dynamically well-determined nova WDs masses have been published, leaving the theoretical predictions poorly tested. The <span class="hlt">recurrence</span> time distributions and mass accretion <span class="hlt">rate</span> distributions of novae are even more poorly known. To address these deficiencies, we have combined our extensive simulations of nova eruptions with the Strope et al. and Schaefer databases of outburst characteristics of Galactic classical and <span class="hlt">recurrent</span> novae (RNe) to determine the masses of 92 WDs in novae. We find that the mean mass (frequency-averaged mean mass) of 82 Galactic classical novae is 1.06 (1.13) M ⊙, while the mean mass of 10 RNe is 1.31 M ⊙. These masses, and the observed nova outburst amplitude and decline time distributions allow us to determine the long-term mass accretion <span class="hlt">rate</span> distribution of classical novae. Remarkably, that value is just 1.3 × 10‑10 M ⊙ yr‑1, which is an order of magnitude smaller than that of cataclysmic binaries in the decades before and after classical nova eruptions. This predicts that old novae become low-mass transfer <span class="hlt">rate</span> systems, and hence dwarf novae, for most of the time between nova eruptions. We determine the mass accretion <span class="hlt">rates</span> of each of the 10 known Galactic <span class="hlt">recurrent</span> nova, finding them to be in the range of 10‑7–10‑8 M ⊙ yr‑1. We are able to predict the <span class="hlt">recurrence</span> time distribution of novae and compare it with the predictions of population synthesis models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19216690','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19216690"><span>Decreased <span class="hlt">recurrence</span> <span class="hlt">rate</span> in the laparoscopic herniorraphy in children: comparison between two techniques.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marte, Antonio; Sabatino, Maria D; Borrelli, Micaela; Parmeggiani, Pio</p> <p>2009-04-01</p> <p>The laparoscopic herniorraphy in children is still associated to a high <span class="hlt">recurrence</span> <span class="hlt">rate</span>. The aim of this study was to assess whether the addition of the lateral incision of the sac to the sole suture of the inner inguinal ring could reduce the <span class="hlt">recurrence</span> <span class="hlt">rate</span>. A retrospective review was performed of the collected data of 248 laparoscopic inguinal hernia repairs in 224 children (175 males, 49 females) between 8 months and 11 years of age (mean age, 5 years; median, 4) in our institution from January 2004 to December 2007. The hernia was unilateral in 204 patients (133 on the right side, 71 on the left) and bilateral in 20 patients. A 5-mm umbilical camera port for a 0-degree laparoscopic optics and two operative 2- or 3-mm reusable trocars inserted in the lower right and left quadrants of the abdominal wall were utilized. In a group of 123 patients, the inner inguinal ring was closed, adopting a W-shaped suture (inguinal ring suture; IRS). In the other group of 101 patients, a lateral incision of the sac of 1-2 cm was carried out before the W-shaped suture of the inner inguinal ring (inguinal ring incision suture; IRIS). At a mean follow-up of 24 months (range, 6-36), 5 of 133 (3.76%) hernias recurred between 6 and 12 months after surgery in the IRS group. In the IRIS group, none of the patients presented with <span class="hlt">recurrence</span>. The <span class="hlt">rate</span> of <span class="hlt">recurrences</span> in the two groups was compared and analyzed with the x2 test. The resulting difference was statistically significant (P < 0.05). In our experience, the incision of the peritoneum lateral to the internal inguinal ring and the W-shaped suture, compared to the sole W-shaped suture, is safe and effective in preventing hernia <span class="hlt">recurrence</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.6654D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.6654D"><span>Turkish Compulsory <span class="hlt">Earthquake</span> Insurance and "Istanbul <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Durukal, E.; Sesetyan, K.; Erdik, M.</p> <p>2009-04-01</p> <p>The city of Istanbul will likely experience substantial direct and indirect losses as a result of a future large (M=7+) <span class="hlt">earthquake</span> with an annual probability of occurrence of about 2%. This paper dwells on the expected building losses in terms of probable maximum and average annualized losses and discusses the results from the perspective of the compulsory <span class="hlt">earthquake</span> insurance scheme operational in the country. The TCIP system is essentially designed to operate in Turkey with sufficient penetration to enable the accumulation of funds in the pool. Today, with only 20% national penetration, and about approximately one-half of all policies in highly <span class="hlt">earthquake</span> prone areas (one-third in Istanbul) the system exhibits signs of adverse selection, inadequate premium structure and insufficient funding. Our findings indicate that the national compulsory <span class="hlt">earthquake</span> insurance pool in Turkey will face difficulties in covering incurring building losses in Istanbul in the occurrence of a large <span class="hlt">earthquake</span>. The annualized <span class="hlt">earthquake</span> losses in Istanbul are between 140-300 million. Even if we assume that the deductible is raised to 15%, the <span class="hlt">earthquake</span> losses that need to be paid after a large <span class="hlt">earthquake</span> in Istanbul will be at about 2.5 Billion, somewhat above the current capacity of the TCIP. Thus, a modification to the system for the insured in Istanbul (or Marmara region) is necessary. This may mean an increase in the premia and deductible <span class="hlt">rates</span>, purchase of larger re-insurance covers and development of a claim processing system. Also, to avoid adverse selection, the penetration <span class="hlt">rates</span> elsewhere in Turkey need to be increased substantially. A better model would be introduction of parametric insurance for Istanbul. By such a model the losses will not be indemnified, however will be directly calculated on the basis of indexed ground motion levels and damages. The immediate improvement of a parametric insurance model over the existing one will be the elimination of the claim processing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.S71B1083R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.S71B1083R"><span><span class="hlt">Earthquake</span> Potential Models for China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rong, Y.; Jackson, D. D.</p> <p>2002-12-01</p> <p>We present three <span class="hlt">earthquake</span> potential estimates for magnitude 5.4 and larger <span class="hlt">earthquakes</span> for China. The potential is expressed as the <span class="hlt">rate</span> density (probability per unit area, magnitude and time). The three methods employ smoothed seismicity-, geologic slip <span class="hlt">rate</span>-, and geodetic strain <span class="hlt">rate</span> data. We tested all three estimates, and the published Global Seismic Hazard Assessment Project (GSHAP) model, against <span class="hlt">earthquake</span> data. We constructed a special <span class="hlt">earthquake</span> catalog which combines previous catalogs covering different times. We used the special catalog to construct our smoothed seismicity model and to evaluate all models retrospectively. All our models employ a modified Gutenberg-Richter magnitude distribution with three parameters: a multiplicative ``a-value," the slope or ``b-value," and a ``corner magnitude" marking a strong decrease of <span class="hlt">earthquake</span> <span class="hlt">rate</span> with magnitude. We assumed the b-value to be constant for the whole study area and estimated the other parameters from regional or local geophysical data. The smoothed seismicity method assumes that the <span class="hlt">rate</span> density is proportional to the magnitude of past <span class="hlt">earthquakes</span> and approximately as the reciprocal of the epicentral distance out to a few hundred kilometers. We derived the upper magnitude limit from the special catalog and estimated local a-values from smoothed seismicity. <span class="hlt">Earthquakes</span> since January 1, 2000 are quite compatible with the model. For the geologic forecast we adopted the seismic source zones (based on geological, geodetic and seismicity data) of the GSHAP model. For each zone, we estimated a corner magnitude by applying the Wells and Coppersmith [1994] relationship to the longest fault in the zone, and we determined the a-value from fault slip <span class="hlt">rates</span> and an assumed locking depth. The geological model fits the <span class="hlt">earthquake</span> data better than the GSHAP model. We also applied the Wells and Coppersmith relationship to individual faults, but the results conflicted with the <span class="hlt">earthquake</span> record. For our geodetic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018AIPC.1967d0056C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018AIPC.1967d0056C"><span>Ads' click-through <span class="hlt">rates</span> predicting based on gated <span class="hlt">recurrent</span> unit neural networks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Qiaohong; Guo, Zixuan; Dong, Wen; Jin, Lingzi</p> <p>2018-05-01</p> <p>In order to improve the effect of online advertising and to increase the revenue of advertising, the gated <span class="hlt">recurrent</span> unit neural networks(GRU) model is used as the ads' click through <span class="hlt">rates</span>(CTR) predicting. Combined with the characteristics of gated unit structure and the unique of time sequence in data, using BPTT algorithm to train the model. Furthermore, by optimizing the step length algorithm of the gated unit <span class="hlt">recurrent</span> neural networks, making the model reach optimal point better and faster in less iterative rounds. The experiment results show that the model based on the gated <span class="hlt">recurrent</span> unit neural networks and its optimization of step length algorithm has the better effect on the ads' CTR predicting, which helps advertisers, media and audience achieve a win-win and mutually beneficial situation in Three-Side Game.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7695K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7695K"><span><span class="hlt">Earthquake</span> Hazard Assessment: Basics of Evaluation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kossobokov, Vladimir</p> <p>2016-04-01</p> <p>Seismic hazard assessment (SHA) is not an easy task that implies a delicate application of statistics to data of limited size and different accuracy. <span class="hlt">Earthquakes</span> follow the Unified Scaling Law that generalizes the Gutenberg-Richter relationship by taking into account naturally fractal distribution of their sources. Moreover, <span class="hlt">earthquakes</span>, including the great and mega events, are clustered in time and their sequences have irregular <span class="hlt">recurrence</span> intervals. Furthermore, <span class="hlt">earthquake</span> related observations are limited to the recent most decades (or centuries in just a few rare cases). Evidently, all this complicates reliable assessment of seismic hazard and associated risks. Making SHA claims, either termless or time dependent (so-called t-DASH), quantitatively probabilistic in the frames of the most popular objectivists' viewpoint on probability requires a long series of "yes/no" trials, which cannot be obtained without an extended rigorous testing of the method predictions against real observations. Therefore, we reiterate the necessity and possibility of applying the modified tools of <span class="hlt">Earthquake</span> Prediction Strategies, in particular, the Error Diagram, introduced by G.M. Molchan in early 1990ies for evaluation of SHA, and the Seismic Roulette null-hypothesis as a measure of the alerted space. The set of errors, i.e. the <span class="hlt">rates</span> of failure and of the alerted space-time volume, compared to those obtained in the same number of random guess trials permits evaluating the SHA method effectiveness and determining the optimal choice of the parameters in regard to specified cost-benefit functions. These and other information obtained in such a testing supplies us with a realistic estimate of confidence in SHA results and related recommendations on the level of risks for decision making in regard to engineering design, insurance, and emergency management. These basics of SHA evaluation are exemplified in brief with a few examples, which analyses in more detail are given in a poster of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27085125','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27085125"><span>Drug treatment <span class="hlt">rates</span> with beta-blockers and ACE-inhibitors/angiotensin receptor blockers and <span class="hlt">recurrences</span> in takotsubo cardiomyopathy: A meta-regression analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brunetti, Natale Daniele; Santoro, Francesco; De Gennaro, Luisa; Correale, Michele; Gaglione, Antonio; Di Biase, Matteo</p> <p>2016-07-01</p> <p>In a recent paper Singh et al. analyzed the effect of drug treatment on <span class="hlt">recurrence</span> of takotsubo cardiomyopathy (TTC) in a comprehensive meta-analysis. The study found that <span class="hlt">recurrence</span> <span class="hlt">rates</span> were independent of clinic utilization of BB prescription, but inversely correlated with ACEi/ARB prescription: authors therefore conclude that ACEi/ARB rather than BB may reduce risk of <span class="hlt">recurrence</span>. We aimed to re-analyze data reported in the study, now weighted for populations' size, in a meta-regression analysis. After multiple meta-regression analysis, we found a significant regression between <span class="hlt">rates</span> of prescription of ACEi and <span class="hlt">rates</span> of <span class="hlt">recurrence</span> of TTC; regression was not statistically significant for BBs. On the bases of our re-analysis, we confirm that <span class="hlt">rates</span> of <span class="hlt">recurrence</span> of TTC are lower in populations of patients with higher <span class="hlt">rates</span> of treatment with ACEi/ARB. That could not necessarily imply that ACEi may prevent <span class="hlt">recurrence</span> of TTC, but barely that, for example, <span class="hlt">rates</span> of <span class="hlt">recurrence</span> are lower in cohorts more compliant with therapy or more prescribed with ACEi because more carefully followed. Randomized prospective studies are surely warranted. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T23D..04A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T23D..04A"><span><span class="hlt">Earthquake</span> Cycle Simulations with <span class="hlt">Rate</span>-and-State Friction and Linear and Nonlinear Viscoelasticity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allison, K. L.; Dunham, E. M.</p> <p>2016-12-01</p> <p>We have implemented a parallel code that simultaneously models both <span class="hlt">rate</span>-and-state friction on a strike-slip fault and off-fault viscoelastic deformation throughout the <span class="hlt">earthquake</span> cycle in 2D. Because we allow fault slip to evolve with a <span class="hlt">rate</span>-and-state friction law and do not impose the depth of the brittle-to-ductile transition, we are able to address: the physical processes limiting the depth of large ruptures (with hazard implications); the degree of strain localization with depth; the relative partitioning of fault slip and viscous deformation in the brittle-to-ductile transition zone; and the relative contributions of afterslip and viscous flow to postseismic surface deformation. The method uses a discretization that accommodates variable off-fault material properties, depth-dependent frictional properties, and linear and nonlinear viscoelastic rheologies. All phases of the <span class="hlt">earthquake</span> cycle are modeled, allowing the model to spontaneously generate <span class="hlt">earthquakes</span>, and to capture afterslip and postseismic viscous flow. We compare the effects of a linear Maxwell rheology, often used in geodetic models, with those of a nonlinear power law rheology, which laboratory data indicates more accurately represents the lower crust and upper mantle. The viscosity of the Maxwell rheology is set by power law rheological parameters with an assumed a geotherm and strain <span class="hlt">rate</span>, producing a viscosity that exponentially decays with depth and is constant in time. In contrast, the power law rheology will evolve an effective viscosity that is a function of the temperature profile and the stress state, and therefore varies both spatially and temporally. We will also integrate the energy equation for the thermomechanical problem, capturing frictional heat generation on the fault and off-fault viscous shear heating, and allowing these in turn to alter the effective viscosity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70042310','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70042310"><span>Global <span class="hlt">earthquake</span> fatalities and population</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Holzer, Thomas L.; Savage, James C.</p> <p>2013-01-01</p> <p>Modern global <span class="hlt">earthquake</span> fatalities can be separated into two components: (1) fatalities from an approximately constant annual background <span class="hlt">rate</span> that is independent of world population growth and (2) fatalities caused by <span class="hlt">earthquakes</span> with large human death tolls, the frequency of which is dependent on world population. <span class="hlt">Earthquakes</span> with death tolls greater than 100,000 (and 50,000) have increased with world population and obey a nonstationary Poisson distribution with <span class="hlt">rate</span> proportional to population. We predict that the number of <span class="hlt">earthquakes</span> with death tolls greater than 100,000 (50,000) will increase in the 21st century to 8.7±3.3 (20.5±4.3) from 4 (7) observed in the 20th century if world population reaches 10.1 billion in 2100. Combining fatalities caused by the background <span class="hlt">rate</span> with fatalities caused by catastrophic <span class="hlt">earthquakes</span> (>100,000 fatalities) indicates global fatalities in the 21st century will be 2.57±0.64 million if the average post-1900 death toll for catastrophic <span class="hlt">earthquakes</span> (193,000) is assumed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.S51F..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S51F..08M"><span>Insight into the rupture process of a rare tsunami <span class="hlt">earthquake</span> from near-field high-<span class="hlt">rate</span> GPS</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Macpherson, K. A.; Hill, E. M.; Elosegui, P.; Banerjee, P.; Sieh, K. E.</p> <p>2011-12-01</p> <p>We investigated the rupture duration and velocity of the October 25, 2010 Mentawai <span class="hlt">earthquake</span> by examining high-<span class="hlt">rate</span> GPS displacement data. This Mw=7.8 <span class="hlt">earthquake</span> appears to have ruptured either an up-dip part of the Sumatran megathrust or a fore-arc splay fault, and produced tsunami run-ups on nearby islands that were out of proportion with its magnitude. It has been described as a so-called "slow tsunami <span class="hlt">earthquake</span>", characterised by a dearth of high-frequency signal and long rupture duration in low-strength, near-surface media. The event was recorded by the Sumatran GPS Array (SuGAr), a network of high-<span class="hlt">rate</span> (1 sec) GPS sensors located on the nearby islands of the Sumatran fore-arc. For this study, the 1 sec time series from 8 SuGAr stations were selected for analysis due to their proximity to the source and high-quality recordings of both static displacements and dynamic waveforms induced by surface waves. The stations are located at epicentral distances of between 50 and 210 km, providing a unique opportunity to observe the dynamic source processes of a tsunami <span class="hlt">earthquake</span> from near-source, high-<span class="hlt">rate</span> GPS. We estimated the rupture duration and velocity by simulating the rupture using the spectral finite-element method SPECFEM and comparing the synthetic time series to the observed surface waves. A slip model from a previous study, derived from the inversion of GPS static offsets and tsunami data, and the CRUST2.0 3D velocity model were used as inputs for the simulations. Rupture duration and velocity were varied for a suite of simulations in order to determine the parameters that produce the best-fitting waveforms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S33A2816W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S33A2816W"><span>Modeling temporal changes of low-frequency <span class="hlt">earthquake</span> bursts near Parkfield, CA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, C.; Daub, E. G.</p> <p>2016-12-01</p> <p>Tectonic tremor and low-frequency <span class="hlt">earthquakes</span> (LFE) are found in the deeper crust of various tectonic environments in the last decade. LFEs are presumed to be caused by failure of deep fault patches during a slow slip event, and the long-term variation in LFE <span class="hlt">recurrence</span> could provide crucial insight into the deep fault zone processes that may lead to future large <span class="hlt">earthquakes</span>. However, the physical mechanisms causing the temporal changes of LFE <span class="hlt">recurrence</span> are still under debate. In this study, we combine observations of long-term changes in LFE burst activities near Parkfield, CA with a brittle and ductile friction (BDF) model, and use the model to constrain the possible physical mechanisms causing the observed long-term changes in LFE burst activities after the 2004 M6 Parkfield <span class="hlt">earthquake</span>. The BDF model mimics the slipping of deep fault patches by a spring-drugged block slider with both brittle and ductile friction components. We use the BDF model to test possible mechanisms including static stress imposed by the Parkfield <span class="hlt">earthquake</span>, changes in pore pressure, tectonic force, afterslip, brittle friction strength, and brittle contact failure distance. The simulation results suggest that changes in brittle friction strength and failure distance are more likely to cause the observed changes in LFE bursts than other mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5617512','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5617512"><span>Colorectal adenoma <span class="hlt">recurrence</span> <span class="hlt">rates</span> among post-polypectomy patients in the placebo-controlled groups of randomized clinical trials: a meta-analysis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Shi, Xin; Yang, Zhiping; Wu, Qiong; Fan, Daiming</p> <p>2017-01-01</p> <p>Background Evidence regarding the benefit of therapy to prevent the post-polypectomy <span class="hlt">recurrence</span> of colorectal adenoma is limited. Endoscopic <span class="hlt">recurrence</span> is the main outcome according to an evaluation of trials involving <span class="hlt">recurrence</span> prevention. Aim To estimate the <span class="hlt">recurrence</span> <span class="hlt">rates</span> of post-polypectomy colorectal adenoma in placebo-controlled arms of randomized clinical trials and to identify the prognostic factors influencing these <span class="hlt">rates</span>. Methods We combined data from all randomized controlled trials evaluating therapies for colorectal adenoma using placebo from 1988 to 2016. The data were combined in a random-effects model. Primary outcomes were endoscopic adenoma and advanced adenoma <span class="hlt">recurrence</span> of colorectal adenoma. Results The pooled estimates of the adenoma <span class="hlt">recurrence</span> <span class="hlt">rates</span> were 37% (95% confidence interval [CI], 33%-41%; range, 33%-52%) at 1 year, 47% (95% CI, 41%-54%; range, 46%-51%) at 2 years, 41% (95% CI, 33%-48%; range, 20%-61%) at 3 years, 48% (95% CI, 38%-57%; range, 37%-53%) at 4 years, and 60% (95% CI, 52%-68%; range, 48%-68%) at 5 years. The pooled estimates of the advanced adenoma <span class="hlt">recurrence</span> <span class="hlt">rates</span> were 10% (95% CI, 6%-15%; range, 7%-13%) at 1 year, 12% (95% CI, 8%-16%; range, 3%-19%) at 3 years, 14% (95% CI, 10%-18%; range, 13%-16%) at 4 years, and 14% (95% CI, 10%-19%; range, 9%-21%) at 5 years. Significant heterogeneity among the randomized clinical trials (P < 0.001) was observed for each <span class="hlt">recurrence</span> <span class="hlt">rate</span>. Conclusions This meta-analysis confirms the heterogeneity of <span class="hlt">recurrence</span> <span class="hlt">rates</span> among post-polypectomy colorectal adenoma patients who received placebo. No single design variable was identified that might explain the heterogeneity. PMID:28977952</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PApGe.tmp...52A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PApGe.tmp...52A"><span>What Can We Learn from a Simple Physics-Based <span class="hlt">Earthquake</span> Simulator?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Artale Harris, Pietro; Marzocchi, Warner; Melini, Daniele</p> <p>2018-03-01</p> <p>Physics-based <span class="hlt">earthquake</span> simulators are becoming a popular tool to investigate on the <span class="hlt">earthquake</span> occurrence process. So far, the development of <span class="hlt">earthquake</span> simulators is commonly led by the approach "the more physics, the better". However, this approach may hamper the comprehension of the outcomes of the simulator; in fact, within complex models, it may be difficult to understand which physical parameters are the most relevant to the features of the seismic catalog at which we are interested. For this reason, here, we take an opposite approach and analyze the behavior of a purposely simple <span class="hlt">earthquake</span> simulator applied to a set of California faults. The idea is that a simple simulator may be more informative than a complex one for some specific scientific objectives, because it is more understandable. Our <span class="hlt">earthquake</span> simulator has three main components: the first one is a realistic tectonic setting, i.e., a fault data set of California; the second is the application of quantitative laws for <span class="hlt">earthquake</span> generation on each single fault, and the last is the fault interaction modeling through the Coulomb Failure Function. The analysis of this simple simulator shows that: (1) the short-term clustering can be reproduced by a set of faults with an almost periodic behavior, which interact according to a Coulomb failure function model; (2) a long-term behavior showing supercycles of the seismic activity exists only in a markedly deterministic framework, and quickly disappears introducing a small degree of stochasticity on the <span class="hlt">recurrence</span> of <span class="hlt">earthquakes</span> on a fault; (3) faults that are strongly coupled in terms of Coulomb failure function model are synchronized in time only in a marked deterministic framework, and as before, such a synchronization disappears introducing a small degree of stochasticity on the <span class="hlt">recurrence</span> of <span class="hlt">earthquakes</span> on a fault. Overall, the results show that even in a simple and perfectly known <span class="hlt">earthquake</span> occurrence world, introducing a small degree of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036286','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036286"><span>Tremor reveals stress shadowing, deep postseismic creep, and depth-dependent slip <span class="hlt">recurrence</span> on the lower-crustal San Andreas fault near Parkfield</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Shelly, David R.; Johnson, Kaj M.</p> <p>2011-01-01</p> <p>The 2003 magnitude 6.5 San Simeon and the 2004 magnitude 6.0 Parkfield <span class="hlt">earthquakes</span> induced small, but significant, static stress changes in the lower crust on the central San Andreas fault, where recently detected tectonic tremor sources provide new constraints on deep fault creep processes. We find that these <span class="hlt">earthquakes</span> affect tremor <span class="hlt">rates</span> very differently, consistent with their differing transferred static shear stresses. The San Simeon event appears to have cast a "stress shadow" north of Parkfield, where tremor activity was stifled for 3-6 weeks. In contrast, the 2004 Parkfield <span class="hlt">earthquake</span> dramatically increased tremor activity <span class="hlt">rates</span> both north and south of Parkfield, allowing us to track deep postseismic slip. Following this event, <span class="hlt">rates</span> initially increased by up to two orders of magnitude for the relatively shallow tremor sources closest to the rupture, with activity in some sources persisting above background <span class="hlt">rates</span> for more than a year. We also observe strong depth dependence in tremor <span class="hlt">recurrence</span> patterns, with shallower sources generally exhibiting larger, less-frequent bursts, possibly signaling a transition toward steady creep with increasing temperature and depth. Copyright 2011 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030759','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030759"><span>Paleoearthquakes on the southern San Andreas Fault, Wrightwood, California, 3000 to 1500 B.C.: A new method for evaluating paleoseismic evidence and <span class="hlt">earthquake</span> horizons</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Scharer, K.M.; Weldon, R.J.; Fumal, T.E.; Biasi, G.P.</p> <p>2007-01-01</p> <p>We present evidence of 11-14 <span class="hlt">earthquakes</span> that occurred between 3000 and 1500 B.C. on the San Andreas fault at the Wrightwood paleoseismic site. <span class="hlt">Earthquake</span> evidence is presented in a novel form in which we rank (high, moderate, poor, or low) the quality of all evidence of ground deformation, which are called "event indicators." Event indicator quality reflects our confidence that the morphologic and sedimentologic evidence can be attributable to a ground-deforming <span class="hlt">earthquake</span> and that the <span class="hlt">earthquake</span> horizon is accurately identified by the morphology of the feature. In four vertical meters of section exposed in ten trenches, we document 316 event indicators attributable to 32 separate stratigraphic horizons. Each stratigraphic horizon is evaluated based on the sum of rank (Rs), maximum rank (Rm), average rank (Ra), number of observations (Obs), and sum of higher-quality event indicators (Rs>1). Of the 32 stratigraphic horizons, 14 contain 83% of the event indicators and are qualified based on the number and quality of event indicators; the remaining 18 do not have satisfactory evidence for further consideration. Eleven of the 14 stratigraphic horizons have sufficient number and quality of event indicators to be qualified as "probable" to "very likely" <span class="hlt">earthquakes</span>; the remaining three stratigraphic horizons are associated with somewhat ambiguous features and are qualified as "possible" <span class="hlt">earthquakes</span>. Although no single measurement defines an obvious threshold for designation as an <span class="hlt">earthquake</span> horizon, Rs, Rm, and Rs>1 correlate best with the interpreted <span class="hlt">earthquake</span> quality. <span class="hlt">Earthquake</span> age distributions are determined from radio-carbon ages of peat samples using a Bayesian approach to layer dating. The average <span class="hlt">recurrence</span> interval for the 10 consecutive and highest-quality <span class="hlt">earthquakes</span> is 111 (93-131) years and individual intervals are ??50% of the average. With comparison with the previously published 14-15 <span class="hlt">earthquake</span> record between A.D. 500 and present, we find no evidence</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23550908','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23550908"><span>Correlating precursory declines in groundwater radon with <span class="hlt">earthquake</span> magnitude.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kuo, T</p> <p>2014-01-01</p> <p>Both studies at the Antung hot spring in eastern Taiwan and at the Paihe spring in southern Taiwan confirm that groundwater radon can be a consistent tracer for strain changes in the crust preceding an <span class="hlt">earthquake</span> when observed in a low-porosity fractured aquifer surrounded by a ductile formation. <span class="hlt">Recurrent</span> anomalous declines in groundwater radon were observed at the Antung D1 monitoring well in eastern Taiwan prior to the five <span class="hlt">earthquakes</span> of magnitude (Mw ): 6.8, 6.1, 5.9, 5.4, and 5.0 that occurred on December 10, 2003; April 1, 2006; April 15, 2006; February 17, 2008; and July 12, 2011, respectively. For <span class="hlt">earthquakes</span> occurring on the longitudinal valley fault in eastern Taiwan, the observed radon minima decrease as the <span class="hlt">earthquake</span> magnitude increases. The above correlation has been proven to be useful for early warning local large <span class="hlt">earthquakes</span>. In southern Taiwan, radon anomalous declines prior to the 2010 Mw 6.3 Jiasian, 2012 Mw 5.9 Wutai, and 2012 ML 5.4 Kaohsiung <span class="hlt">earthquakes</span> were also recorded at the Paihe spring. For <span class="hlt">earthquakes</span> occurring on different faults in southern Taiwan, the correlation between the observed radon minima and the <span class="hlt">earthquake</span> magnitude is not yet possible. © 2013, National Ground Water Association.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23855226','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23855226"><span>[A case of "oneiroid Erlebnisform" influenced by the Great East Japan <span class="hlt">Earthquake</span>].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hori, Takafumi; Ishii, Terumi; Hisanaga, Akihito; Tatsuki, Aeka; Tachikawa, Hirokazu; Asada, Takashi</p> <p>2013-01-01</p> <p>Following the Great East Japan <span class="hlt">Earthquake</span>, although there are a growing number of reports on the care of the mental health of victims and supporters, the influence of this disaster on individuals with mental disorders has not yet been sufficiently clarified. Here, we present a case of "oneiroid Erlebnisform" (Mayer-Gross, W.), which was influenced by the disaster and relapsed one year after the <span class="hlt">earthquake</span>. We discussed the meaning of this experience and the factors leading to <span class="hlt">recurrence</span> in this case. A male international student in his thirties had repeatedly suffered from acute episodic alteration of consciousness. Although he had experienced anxiety just after the disaster, he showed improvement during his temporary evacuation to Western Japan. Nearly one year after the disaster, however, he relapsed, with symptoms characteristic of an oneiroid state. The patient stated that he was a fuel rod in the Fukushima nuclear power plant, and he then immersed himself in a bathtub full of water in order to avoid meltdown. According to ICD-10, the patient was diagnosed with acute polymorphic psychotic disorder without symptoms of schizophrenia (F23.0). In addition to the alteration of consciousness as the main symptom, since there was no decrease in the level of personolity function, it was also considered that the diagnosis of this case was atypical psychosis, as proposed by Mitsuda and Hatotani. In the oneiroid experience, a variety of visual hallucinations, illusions, and images had appeared one after another. We can find catastrophe and salvation as the main themes in this state, related to the disaster and nuclear accident. Unloading situation after thesis defense, insufficient sleep, poor medication adherence, and the increased frequency of <span class="hlt">earthquakes</span> were important factors in the <span class="hlt">recurrence</span> of the present case. To continue research in Japan after the <span class="hlt">earthquake</span>, the decision was accompanied by anxiety for the patient. One year after the <span class="hlt">earthquake</span>, the patient was</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Tectp.672..228Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Tectp.672..228Q"><span>The 2010-2011 Canterbury <span class="hlt">Earthquake</span> Sequence: Environmental effects, seismic triggering thresholds and geologic legacy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quigley, Mark C.; Hughes, Matthew W.; Bradley, Brendon A.; van Ballegooy, Sjoerd; Reid, Catherine; Morgenroth, Justin; Horton, Travis; Duffy, Brendan; Pettinga, Jarg R.</p> <p>2016-03-01</p> <p> characteristics. However, the severity of a given environmental response at any given site related predominantly to ground shaking characteristics (PGA, peak ground velocities) and site conditions (water table depth, soil type, geomorphic and topographic setting) rather than <span class="hlt">earthquake</span> Mw. In most cases, the most severe liquefaction, rockfall, cliff collapse, subsidence, flooding, tree damage, and biologic habitat changes were triggered by proximal, moderate magnitude (Mw ≤ 6.2) <span class="hlt">earthquakes</span> on blind faults. CES environmental effects will be incompletely preserved in the geologic record and variably diagnostic of spatial and temporal <span class="hlt">earthquake</span> clustering. Liquefaction feeder dikes in areas of severe and <span class="hlt">recurrent</span> liquefaction will provide the best preserved and potentially most diagnostic CES features. Rockfall talus deposits and boulders will be well preserved and potentially diagnostic of the strong intensity of CES shaking, but challenging to decipher in terms of single versus multiple events. Most other phenomena will be transient (e.g., distal groundwater responses), not uniquely diagnostic of <span class="hlt">earthquakes</span> (e.g., flooding), or more ambiguous (e.g. biologic changes). Preliminary palaeoseismic investigations in the CES region indicate <span class="hlt">recurrence</span> of liquefaction in susceptible sediments of 100 to 300 yr, <span class="hlt">recurrence</span> of severe rockfall event(s) of ca. 6000 to 8000 yr, and <span class="hlt">recurrence</span> of surface rupturing on the largest CES source fault of ca. 20,000 to 30,000 yr. These data highlight the importance of utilising multiple proxy datasets in palaeoearthquake studies. The severity of environmental effects triggered during the strongest CES <span class="hlt">earthquakes</span> was as great as or equivalent to any historic or prehistoric effects recorded in the geologic record. We suggest that the shaking caused by rupture of local blind faults in the CES comprised a 'worst case' seismic shaking scenario for parts of the Christchurch urban area. Moderate Mw blind fault <span class="hlt">earthquakes</span> may contribute the highest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.458..170R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.458..170R"><span><span class="hlt">Recurrence</span> <span class="hlt">rate</span> and magma effusion <span class="hlt">rate</span> for the latest volcanism on Arsia Mons, Mars</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, Jacob A.; Wilson, James A.; Connor, Charles B.; Bleacher, Jacob E.; Kiyosugi, Koji</p> <p>2017-01-01</p> <p>Magmatism and volcanism have evolved the Martian lithosphere, surface, and climate throughout the history of Mars. Constraining the <span class="hlt">rates</span> of magma generation and timing of volcanism on the surface clarifies the ways in which magma and volcanic activity have shaped these Martian systems. The ages of lava flows on other planets are often estimated using impact crater counts, assuming that the number and size-distribution of impact craters per unit area reflect the time the lava flow has been on the surface and exposed to potential impacts. Here we show that impact crater age model uncertainty is reduced by adding stratigraphic information observed at locations where neighboring lavas abut each other, and demonstrate the significance of this reduction in age uncertainty for understanding the history of a volcanic field comprising 29 vents in the 110-km-diameter caldera of Arsia Mons, Mars. Each vent within this caldera produced lava flows several to tens of kilometers in length; these vents are likely among the youngest on Mars, since no impact craters in their lava flows are larger than 1 km in diameter. First, we modeled the age of each vent with impact crater counts performed on their corresponding lava flows and found very large age uncertainties for the ages of individual vents, often spanning the estimated age for the entire volcanic field. The age model derived from impact crater counts alone is broad and unimodal, with estimated peak activity in the field around 130 Ma. Next we applied our volcano event age model (VEAM), which uses a directed graph of stratigraphic relationships and random sampling of the impact crater age determinations to create alternative age models. Monte Carlo simulation was used to create 10,000 possible vent age sets. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> of volcanism is calculated for each possible age set, and these <span class="hlt">rates</span> are combined to calculate the median <span class="hlt">recurrence</span> <span class="hlt">rate</span> of all simulations. Applying this approach to the 29 volcanic vents, volcanism</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20170002329&hterms=koji&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dkoji','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20170002329&hterms=koji&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dkoji"><span><span class="hlt">Recurrence</span> <span class="hlt">Rate</span> and Magma Effusion <span class="hlt">Rate</span> for the Latest Volcanism on Arsia Mons, Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, Jacob A.; Wilson, James A.; Connor, Charles B.; Bleacher, Jacob E.; Kiyosugi, Koji</p> <p>2016-01-01</p> <p>Magmatism and volcanism have evolved the Martian lithosphere, surface, and climate throughout the history of Mars. Constraining the <span class="hlt">rates</span> of magma generation and timing of volcanism on the surface clarifies the ways in which magma and volcanic activity have shaped these Martian systems. The ages of lava flows on other planets are often estimated using impact crater counts, assuming that the number and size-distribution of impact craters per unit area reflect the time the lava flow has been on the surface and exposed to potential impacts. Here we show that impact crater age model uncertainty is reduced by adding stratigraphic information observed at locations where neighboring lavas abut each other, and demonstrate the significance of this reduction in age uncertainty for understanding the history of a volcanic field comprising 29 vents in the 110-kilometer-diameter caldera of Arsia Mons, Mars. Each vent within this caldera produced lava flows several to tens of kilometers in length; these vents are likely among the youngest on Mars, since no impact craters in their lava flows are larger than 1 kilometer in diameter. First, we modeled the age of each vent with impact crater counts performed on their corresponding lava flows and found very large age uncertainties for the ages of individual vents, often spanning the estimated age for the entire volcanic field. The age model derived from impact crater counts alone is broad and unimodal, with estimated peak activity in the field around 130Ma (megaannum, 1 million years). Next we applied our volcano event age model (VEAM), which uses a directed graph of stratigraphic relationships and random sampling of the impact crater age determinations to create alternative age models. Monte Carlo simulation was used to create 10,000 possible vent age sets. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> of volcanism is calculated for each possible age set, and these <span class="hlt">rates</span> are combined to calculate the median <span class="hlt">recurrence</span> <span class="hlt">rate</span> of all simulations. Applying this</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018E%26PSL.482..377C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018E%26PSL.482..377C"><span><span class="hlt">Earthquake</span> induced variations in extrusion <span class="hlt">rate</span>: A numerical modeling approach to the 2006 eruption of Merapi Volcano (Indonesia)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carr, Brett B.; Clarke, Amanda B.; de'Michieli Vitturi, Mattia</p> <p>2018-01-01</p> <p>Extrusion <span class="hlt">rates</span> during lava dome-building eruptions are variable and eruption sequences at these volcanoes generally have multiple phases. Merapi Volcano, Java, Indonesia, exemplifies this common style of activity. Merapi is one of Indonesia's most active volcanoes and during the 20th and early 21st centuries effusive activity has been characterized by long periods of very slow (<0.1 m3 s-1) extrusion <span class="hlt">rate</span> interrupted every few years by short episodes of elevated extrusion <span class="hlt">rates</span> (1-4 m3 s-1) lasting weeks to months. One such event occurred in May-July 2006, and previous research has identified multiple phases with different extrusion <span class="hlt">rates</span> and styles of activity. Using input values established in the literature, we apply a 1D, isothermal, steady-state numerical model of magma ascent in a volcanic conduit to explain the variations and gain insight into corresponding conduit processes. The peak phase of the 2006 eruption occurred in the two weeks following the May 27 Mw 6.4 <span class="hlt">earthquake</span> 50 km to the south. Previous work has suggested that the peak extrusion <span class="hlt">rates</span> observed in early June were triggered by the <span class="hlt">earthquake</span> through either dynamic stress-induced overpressure or the addition of CO2 due to decarbonation and gas escape from new fractures in the bedrock. We use the numerical model to test the feasibility of these proposed hypotheses and show that, in order to explain the observed change in extrusion <span class="hlt">rate</span>, an increase of approximately 5-7 MPa in magma storage zone overpressure is required. We also find that the addition of ∼1000 ppm CO2 to some portion of the magma in the storage zone following the <span class="hlt">earthquake</span> reduces water solubility such that gas exsolution is sufficient to generate the required overpressure. Thus, the proposed mechanism of CO2 addition is a viable explanation for the peak phase of the Merapi 2006 eruption. A time-series of extrusion <span class="hlt">rate</span> shows a sudden increase three days following the <span class="hlt">earthquake</span>. We explain this three-day delay by the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5667647-perspectives-earthquake-hazards-new-madrid-seismic-zone-missouri','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5667647-perspectives-earthquake-hazards-new-madrid-seismic-zone-missouri"><span>Perspectives on <span class="hlt">earthquake</span> hazards in the New Madrid seismic zone, Missouri</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Thenhaus, P.C.</p> <p>1990-01-01</p> <p>A sequence of three great <span class="hlt">earthquakes</span> struck the Central United States during the winter of 1811-12 in the area of New Madrid, Missouri. They are considered to be the greatest <span class="hlt">earthquakes</span> in the conterminous U.S. because they were felt and caused damage at far greater distances than any other <span class="hlt">earthquakes</span> in US history. In contrast to California, where <span class="hlt">earthquakes</span> are felt frequently, the damaging <span class="hlt">earthquakes</span> that have occurred in the Eastern US are generally regarded as only historical phenomena. A fundamental problem in the Eastern US, therefore, is that the <span class="hlt">earthquake</span> hazard is not generally considered today in land-use andmore » civic planning. This article offers perspectives on the <span class="hlt">earthquake</span> hazard of the New Madrid seismic zone through discussions of the geology of the Mississippi Embayment, the historical <span class="hlt">earthquakes</span> that have occurred there, the <span class="hlt">earthquake</span> risk, and the tools that geoscientists have to study the region. The so-called <span class="hlt">earthquake</span> hazard is defined by the characterization of the physical attributes of the geological structures that cause <span class="hlt">earthquakes</span>, the estimation of the <span class="hlt">recurrence</span> times of the <span class="hlt">earthquakes</span>, their potential size, and the expected ground motions. The term <span class="hlt">earthquake</span> risk, on the other hand, refers to aspects of the expected damage to manmade structures and to lifelines as a result of the <span class="hlt">earthquake</span> hazard.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhDT.......116R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhDT.......116R"><span>Evaluation of <span class="hlt">earthquake</span> potential in China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rong, Yufang</p> <p></p> <p>I present three <span class="hlt">earthquake</span> potential estimates for magnitude 5.4 and larger <span class="hlt">earthquakes</span> for China. The potential is expressed as the <span class="hlt">rate</span> density (that is, the probability per unit area, magnitude and time). The three methods employ smoothed seismicity-, geologic slip <span class="hlt">rate</span>-, and geodetic strain <span class="hlt">rate</span> data. I test all three estimates, and another published estimate, against <span class="hlt">earthquake</span> data. I constructed a special <span class="hlt">earthquake</span> catalog which combines previous catalogs covering different times. I estimated moment magnitudes for some events using regression relationships that are derived in this study. I used the special catalog to construct the smoothed seismicity model and to test all models retrospectively. In all the models, I adopted a kind of Gutenberg-Richter magnitude distribution with modifications at higher magnitude. The assumed magnitude distribution depends on three parameters: a multiplicative " a-value," the slope or "b-value," and a "corner magnitude" marking a rapid decrease of <span class="hlt">earthquake</span> <span class="hlt">rate</span> with magnitude. I assumed the "b-value" to be constant for the whole study area and estimated the other parameters from regional or local geophysical data. The smoothed seismicity method assumes that the <span class="hlt">rate</span> density is proportional to the magnitude of past <span class="hlt">earthquakes</span> and declines as a negative power of the epicentral distance out to a few hundred kilometers. I derived the upper magnitude limit from the special catalog, and estimated local "a-values" from smoothed seismicity. I have begun a "prospective" test, and <span class="hlt">earthquakes</span> since the beginning of 2000 are quite compatible with the model. For the geologic estimations, I adopted the seismic source zones that are used in the published Global Seismic Hazard Assessment Project (GSHAP) model. The zones are divided according to geological, geodetic and seismicity data. Corner magnitudes are estimated from fault length, while fault slip <span class="hlt">rates</span> and an assumed locking depth determine <span class="hlt">earthquake</span> <span class="hlt">rates</span>. The geological model</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70028656','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70028656"><span>Slip on the San Andreas fault at Parkfield, California, over two <span class="hlt">earthquake</span> cycles, and the implications for seismic hazard</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Murray, J.; Langbein, J.</p> <p>2006-01-01</p> <p>Parkfield, California, which experienced M 6.0 <span class="hlt">earthquakes</span> in 1934, 1966, and 2004, is one of the few locales for which geodetic observations span multiple <span class="hlt">earthquake</span> cycles. We undertake a comprehensive study of deformation over the most recent <span class="hlt">earthquake</span> cycle and explore the results in the context of geodetic data collected prior to the 1966 event. Through joint inversion of the variety of Parkfield geodetic measurements (trilateration, two-color laser, and Global Positioning System), including previously unpublished two-color data, we estimate the spatial distribution of slip and slip <span class="hlt">rate</span> along the San Andreas using a fault geometry based on precisely relocated seismicity. Although the three most recent Parkfield <span class="hlt">earthquakes</span> appear complementary in their along-strike distributions of slip, they do not produce uniform strain release along strike over multiple seismic cycles. Since the 1934 <span class="hlt">earthquake</span>, more than 1 m of slip deficit has accumulated on portions of the fault that slipped in the 1966 and 2004 <span class="hlt">earthquakes</span>, and an average of 2 m of slip deficit exists on the 33 km of the fault southeast of Gold Hill to be released in a future, perhaps larger, <span class="hlt">earthquake</span>. It appears that the fault is capable of partially releasing stored strain in moderate <span class="hlt">earthquakes</span>, maintaining a disequilibrium through multiple <span class="hlt">earthquake</span> cycles. This complicates the application of simple <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> models that assume only the strain accumulated since the most recent event is relevant to the size or timing of an upcoming <span class="hlt">earthquake</span>. Our findings further emphasize that accumulated slip deficit is not sufficient for <span class="hlt">earthquake</span> nucleation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25952091','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25952091"><span><span class="hlt">Rate</span> of duodenal-biliary reflux increases in patients with <span class="hlt">recurrent</span> common bile duct stones: evidence from barium meal examination.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhang, Rongchun; Luo, Hui; Pan, Yanglin; Zhao, Lina; Dong, Junqiang; Liu, Zhiguo; Wang, Xiangping; Tao, Qin; Lu, Guohua; Guo, Xuegang</p> <p>2015-10-01</p> <p>Stone <span class="hlt">recurrence</span> is a common late adverse event after ERCP in patients with common bile duct stones (CBDS). Duodenal-biliary reflux (DBR) is considered a major cause of CBDS <span class="hlt">recurrence</span>. However, specific evidence is still lacking. To investigate the DBR <span class="hlt">rate</span> in patients with <span class="hlt">recurrent</span> CBDS after ERCP. A prospective case-control study. A tertiary center. During follow-up, patients with a history of either <span class="hlt">recurrent</span> CBDS (<span class="hlt">recurrence</span> group) or nonrecurrent CBDS (control group) were invited to participate in the study. All patients had previously undergone successful CBDS removal by ERCP. Patients in the control group were matched with the <span class="hlt">recurrence</span> group by age and gender in a 1:1 ratio. Patients with gallbladder stones, hepatolithiasis, remnant CBDS, CBD strictures, or stents were excluded. Standard barium meal examination, MRCP, and enhanced abdominal CT. DBR. Thirty-two patients with a history of <span class="hlt">recurrent</span> CBDS and 32 matched control subjects were enrolled. Baseline characteristics and parameters regarding the first ERCP were comparable between the 2 groups. The DBR <span class="hlt">rate</span> was significantly higher in the <span class="hlt">recurrent</span> than in the control group (68.8% vs 15.6%, P < .001). Multivariate analysis indicated that DBR (OR, 9.59; 95% CI, 2.65-34.76) and acute distal CBD angulation (OR, 5.48; 95% CI, 1.52-19.78) were independent factors associated with CBDS <span class="hlt">recurrence</span>. DBR <span class="hlt">rates</span> in patients with no, single, or multiple <span class="hlt">recurrences</span> were 15.6%, 60.9%, and 88.9%, respectively (P < .001). Intrahepatic bile duct reflux was more common in patients with multiple <span class="hlt">recurrences</span>. Small sample size. DBR is correlated with CBDS <span class="hlt">recurrence</span> in patients who had previously undergone ERCP. DBR and acute distal CBD angulation are 2 independent risk factors related to stone <span class="hlt">recurrence</span>. ( NCT02329977.) Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70101108','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70101108"><span>Missing great <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hough, Susan E.</p> <p>2013-01-01</p> <p>The occurrence of three <span class="hlt">earthquakes</span> with moment magnitude (Mw) greater than 8.8 and six <span class="hlt">earthquakes</span> larger than Mw 8.5, since 2004, has raised interest in the long-term global <span class="hlt">rate</span> of great <span class="hlt">earthquakes</span>. Past studies have focused on the analysis of <span class="hlt">earthquakes</span> since 1900, which roughly marks the start of the instrumental era in seismology. Before this time, the catalog is less complete and magnitude estimates are more uncertain. Yet substantial information is available for <span class="hlt">earthquakes</span> before 1900, and the catalog of historical events is being used increasingly to improve hazard assessment. Here I consider the catalog of historical <span class="hlt">earthquakes</span> and show that approximately half of all Mw ≥ 8.5 <span class="hlt">earthquakes</span> are likely missing or underestimated in the 19th century. I further present a reconsideration of the felt effects of the 8 February 1843, Lesser Antilles <span class="hlt">earthquake</span>, including a first thorough assessment of felt reports from the United States, and show it is an example of a known historical <span class="hlt">earthquake</span> that was significantly larger than initially estimated. The results suggest that incorporation of best available catalogs of historical <span class="hlt">earthquakes</span> will likely lead to a significant underestimation of seismic hazard and/or the maximum possible magnitude in many regions, including parts of the Caribbean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70023066','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70023066"><span>Viscoelastic shear zone model of a strike-slip <span class="hlt">earthquake</span> cycle</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pollitz, F.F.</p> <p>2001-01-01</p> <p>I examine the behavior of a two-dimensional (2-D) strike-slip fault system embedded in a 1-D elastic layer (schizosphere) overlying a uniform viscoelastic half-space (plastosphere) and within the boundaries of a finite width shear zone. The viscoelastic coupling model of Savage and Prescott [1978] considers the viscoelastic response of this system, in the absence of the shear zone boundaries, to an <span class="hlt">earthquake</span> occurring within the upper elastic layer, steady slip beneath a prescribed depth, and the superposition of the responses of multiple <span class="hlt">earthquakes</span> with characteristic slip occurring at regular intervals. So formulated, the viscoelastic coupling model predicts that sufficiently long after initiation of the system, (1) average fault-parallel velocity at any point is the average slip <span class="hlt">rate</span> of that side of the fault and (2) far-field velocities equal the same constant <span class="hlt">rate</span>. Because of the sensitivity to the mechanical properties of the schizosphere-plastosphere system (i.e., elastic layer thickness, plastosphere viscosity), this model has been used to infer such properties from measurements of interseismic velocity. Such inferences exploit the predicted behavior at a known time within the <span class="hlt">earthquake</span> cycle. By modifying the viscoelastic coupling model to satisfy the additional constraint that the absolute velocity at prescribed shear zone boundaries is constant, I find that even though the time-averaged behavior remains the same, the spatiotemporal pattern of surface deformation (particularly its temporal variation within an <span class="hlt">earthquake</span> cycle) is markedly different from that predicted by the conventional viscoelastic coupling model. These differences are magnified as plastosphere viscosity is reduced or as the <span class="hlt">recurrence</span> interval of periodic <span class="hlt">earthquakes</span> is lengthened. Application to the interseismic velocity field along the Mojave section of the San Andreas fault suggests that the region behaves mechanically like a ???600-km-wide shear zone accommodating 50 mm/yr fault</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/1111713-new-constraints-slip-rates-recurrence-intervals-strain-partitioning-beneath-pyramid-lake-nevada','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/1111713-new-constraints-slip-rates-recurrence-intervals-strain-partitioning-beneath-pyramid-lake-nevada"><span>New constraints on slip-<span class="hlt">rates</span>, <span class="hlt">recurrence</span> intervals, and strain partitioning beneath Pyramid Lake, Nevada</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Eisses, Amy</p> <p></p> <p>A high-resolution CHIRP seismic survey of Pyramid Lake, Nevada, located within the northern Walker Lane Deformation Belt, was conducted in summer 2010. Seismic CHIRP data with submeter vertical accuracy, together with piston and gravity cores, were used to calculate Holocene vertical slip <span class="hlt">rates</span>, relative <span class="hlt">earthquake</span> timing, and produce the first complete fault map beneath the lake. More than 500 line-kilometers of CHIRP data imaged complex fault patterns throughout the basin. Fault architecture beneath Pyramid Lake highlights a polarity flip, where down-to-the west patterns of sedimentation near the dextral Pyramid Lake fault to the south give way to down-to-the-east geometries tomore » the north within a mostly normal (i.e., Lake Range fault) and transtensional environment. The Lake Range fault predominantly controls extensional deformation within the northern two-thirds of the basin and exhibits varying degrees of asymmetric tilting and divergence due to along-strike segmentation. This observation is likely a combination of fault segments splaying onshore moving the focus of extension away from the lake coupled with some true along-strike differences in slip-<span class="hlt">rate</span>. The combination of normal and oblique-slip faults in the northern basin gives Pyramid Lake its distinctive “fanning open to the north” tectonic geometry. The dense network of oblique-slip faults in the northwestern region of the lake, in contrast to the well-defined Lake Range fault, are short and discontinuous in nature, and possible represent a nascent shear zone. Preliminary vertical slip-<span class="hlt">rates</span> measured across the Lake Range and other faults provide new estimates on the extension across the Pyramid Lake basin. A minimum vertical slip <span class="hlt">rate</span> of ~1.0 mm/yr is estimated along the Lake Range fault, which yields a potential <span class="hlt">earthquake</span> magnitude range between M6.4 and M7.0. A rapid influx of sediment was deposited shortly after the end of the Tioga glaciation somewhere between 12.5 ka to 9.5 ka and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhyA..419..203N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhyA..419..203N"><span>Intra-day response of foreign exchange markets after the Tohoku-Oki <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakano, Shuhei; Hirata, Yoshito; Iwayama, Koji; Aihara, Kazuyuki</p> <p>2015-02-01</p> <p>Although an economy is influenced by a natural disaster, the market response to the disaster during the first 24 hours is not clearly understood. Here we show that an <span class="hlt">earthquake</span> quickly causes temporal changes in a foreign exchange market by examining the case of the Tohoku-Oki <span class="hlt">earthquake</span>. <span class="hlt">Recurrence</span> plots and statistical change point detection independently show that the United States dollar-Japanese yen market responded to the <span class="hlt">earthquake</span> activity without delay and with the delay of about 2 minutes, respectively. These findings support that the efficient market hypothesis nearly holds now in the time scale of minutes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70159467','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70159467"><span>A century of induced <span class="hlt">earthquakes</span> in Oklahoma?</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hough, Susan E.; Page, Morgan T.</p> <p>2015-01-01</p> <p>Seismicity <span class="hlt">rates</span> have increased sharply since 2009 in the central and eastern United States, with especially high <span class="hlt">rates</span> of activity in the state of Oklahoma. Growing evidence indicates that many of these events are induced, primarily by injection of wastewater in deep disposal wells. The upsurge in activity has raised two questions: What is the background <span class="hlt">rate</span> of tectonic <span class="hlt">earthquakes</span> in Oklahoma? How much has the <span class="hlt">rate</span> varied throughout historical and early instrumental times? In this article, we show that (1) seismicity <span class="hlt">rates</span> since 2009 surpass previously observed <span class="hlt">rates</span> throughout the twentieth century; (2) several lines of evidence suggest that most of the significant <span class="hlt">earthquakes</span> in Oklahoma during the twentieth century were likely induced by oil production activities, as they exhibit statistically significant temporal and spatial correspondence with disposal wells, and intensity measurements for the 1952 El Reno <span class="hlt">earthquake</span> and possibly the 1956 Tulsa County <span class="hlt">earthquake</span> follow the pattern observed in other induced <span class="hlt">earthquakes</span>; and (3) there is evidence for a low level of tectonic seismicity in southeastern Oklahoma associated with the Ouachita structural belt. The 22 October 1882 Choctaw Nation <span class="hlt">earthquake</span>, for which we estimate Mw 4.8, occurred in this zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21334827','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21334827"><span>Analysis of the burns profile and the admission <span class="hlt">rate</span> of severely burned adult patient to the National Burn Center of Chile after the 2010 <span class="hlt">earthquake</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Albornoz, Claudia; Villegas, Jorge; Sylvester, Marilu; Peña, Veronica; Bravo, Iside</p> <p>2011-06-01</p> <p>Chile is located in the Ring of Fire, in South America. An <span class="hlt">earthquake</span> 8.8° affected 80% of the population in February 27th, 2010. This study was conducted to assess any change in burns profile caused by the <span class="hlt">earthquake</span>. This was an ecologic study. We compared the 4 months following the <span class="hlt">earthquake</span> in 2009 and 2010. age, TBSA, deep TBSA, agent, specific mortality <span class="hlt">rate</span> and <span class="hlt">rate</span> of admissions to the National burn Center of Chile. Mann-Whitney test and a Poisson regression were performed. Age, agent, TBSA and deep TBSA percentages did not show any difference. Mortality <span class="hlt">rate</span> was lower in 2010 (0.52 versus 1.22 per 1,000,000 habitants) but no meaningful difference was found (Poisson regression p = 0.06). Admission <span class="hlt">rate</span> was lower in 2010, 4.6 versus 5.6 per 1,000,000 habitants, but no differences were found (p = 0.26). There was not any admissions directly related to the <span class="hlt">earthquake</span>. As we do not have incidence registries in Chile, we propose to use the <span class="hlt">rate</span> of admission to the National Burn Reference Center as an incidence estimator. There was not any significant difference in the burn profile, probably because of the time of the <span class="hlt">earthquake</span> (3 am). We conclude the <span class="hlt">earthquake</span> did not affect the way the Chilean people get burned. Copyright © 2011 Elsevier Ltd and ISBI. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22458646-patterns-recurrence-after-low-dose-rate-prostate-brachytherapy-population-based-study-consecutive-low-intermediate-risk-patients','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22458646-patterns-recurrence-after-low-dose-rate-prostate-brachytherapy-population-based-study-consecutive-low-intermediate-risk-patients"><span>Patterns of <span class="hlt">Recurrence</span> After Low-Dose-<span class="hlt">Rate</span> Prostate Brachytherapy: A Population-Based Study of 2223 Consecutive Low- and Intermediate-Risk Patients</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Lo, Andrea C.; Morris, W. James, E-mail: JMorris@bccancer.bc.ca; Pickles, Tom</p> <p></p> <p>Objectives: This study examined patterns of <span class="hlt">recurrence</span> after low–dose-<span class="hlt">rate</span> prostate brachytherapy (LDR-PB), estimated local <span class="hlt">recurrence</span> <span class="hlt">rate</span> and compared that <span class="hlt">rate</span> to the estimated local <span class="hlt">recurrence</span> <span class="hlt">rate</span> after radical prostatectomy (RP). Methods and Materials: A prospective database was maintained with clinical, dosimetric, and outcome data for all LDR-PB implantation procedures performed at our institution. From 1998 to 2008, 2223 patients with prostate cancer received LDR-PB without supplemental external beam radiation therapy. Patients who developed Phoenix-defined biochemical failure were reviewed for sites of relapse and investigations completed. Results: At a median follow-up of 5 years, 108 of 2223 patients (4.8%) developed biochemical relapse.more » In 1 additional patient, local relapse was found on transurethral prostate resection, but his prostate-specific antigen concentration was well short of triggering Phoenix-defined failure. Of the 109 patients with disease relapse, 18 of 2223 (0.8%) had a proven local <span class="hlt">recurrence</span>, and 30 of 2223 (1.3%) had a proven distant <span class="hlt">recurrence</span>. The remaining 61 of 2223 patients (2.7%) had unidentified sites of <span class="hlt">recurrence</span>; of these, 57 patients (93%) had digital rectal examinations (DREs), 18 (30%) had post-treatment biopsies, 45 (74%) had bone scans, and 34 (56%) had computed tomography imaging of the abdomen and pelvis. If every biochemical failure were local, the local <span class="hlt">recurrence</span> <span class="hlt">rate</span> would be as high as 4.9%; however, by excluding those with proven distant failure and those with both a negative DRE and biopsy, we estimate that the local <span class="hlt">recurrence</span> <span class="hlt">rate</span> is 2.7% or less. Conclusions: In the context of limitations of the study design, our population-based analysis indicates that the local <span class="hlt">recurrence</span> <span class="hlt">rate</span> after LDR-PB is as low or lower than that after RP in our jurisdiction.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25308517','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25308517"><span>Reducing sojourn points from <span class="hlt">recurrence</span> plots to improve transition detection: Application to fetal heart <span class="hlt">rate</span> transitions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zaylaa, Amira; Charara, Jamal; Girault, Jean-Marc</p> <p>2015-08-01</p> <p>The analysis of biomedical signals demonstrating complexity through <span class="hlt">recurrence</span> plots is challenging. Quantification of <span class="hlt">recurrences</span> is often biased by sojourn points that hide dynamic transitions. To overcome this problem, time series have previously been embedded at high dimensions. However, no one has quantified the elimination of sojourn points and <span class="hlt">rate</span> of detection, nor the enhancement of transition detection has been investigated. This paper reports our on-going efforts to improve the detection of dynamic transitions from logistic maps and fetal hearts by reducing sojourn points. Three signal-based <span class="hlt">recurrence</span> plots were developed, i.e. embedded with specific settings, derivative-based and m-time pattern. Determinism, cross-determinism and percentage of reduced sojourn points were computed to detect transitions. For logistic maps, an increase of 50% and 34.3% in sensitivity of detection over alternatives was achieved by m-time pattern and embedded <span class="hlt">recurrence</span> plots with specific settings, respectively, and with a 100% specificity. For fetal heart <span class="hlt">rates</span>, embedded <span class="hlt">recurrence</span> plots with specific settings provided the best performance, followed by derivative-based <span class="hlt">recurrence</span> plot, then unembedded <span class="hlt">recurrence</span> plot using the determinism parameter. The relative errors between healthy and distressed fetuses were 153%, 95% and 91%. More than 50% of sojourn points were eliminated, allowing better detection of heart transitions triggered by gaseous exchange factors. This could be significant in improving the diagnosis of fetal state. Copyright © 2014 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5449222','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5449222"><span>17-alpha Hydroxyprogesterone Caproate did not reduce the <span class="hlt">rate</span> of <span class="hlt">recurrent</span> preterm birth in a prospective cohort study</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Nelson, David B.; McIntire, Donald D.; McDonald, Jeffrey; Gard, John; Turrichi, Paula; Leveno, Kenneth J.</p> <p>2017-01-01</p> <p>Background 17-alpha hydroxyprogesterone caproate for prevention of <span class="hlt">recurrent</span> preterm birth is recommended for use in the United States. Objective To assess the clinical effectiveness of 17-alpha hydroxyprogesterone caproate to prevent <span class="hlt">recurrent</span> preterm birth ≤ 35 weeks compared to similar births in our obstetric population prior to the implementation of 17-alpha hydroxyprogesterone caproate. Study Design This was a prospective cohort study of 17-alpha hydroxyprogesterone caproate in our obstetric population. The primary outcome was the <span class="hlt">recurrence</span> of birth ≤ 35 weeks for the entire study cohort compared to a historical referent <span class="hlt">rate</span> of 16.8% of <span class="hlt">recurrent</span> preterm birth in our population. There were three secondary outcomes. First, did 17-alpha hydroxyprogesterone caproate modify a woman’s history of preterm birth when taking into account her prior number and sequence of preterm and term births? Second, was <span class="hlt">recurrence</span> of preterm birth related to 17-alpha hydroxyprogesterone caproate plasma concentration? Third, was duration of pregnancy modified by 17-alpha hydroxyprogesterone caproate treatment compared to a prior preterm birth? Results Between January 2012 and March 2016, 430 consecutive women with prior births ≤ 35 weeks were treated with 17-alpha hydroxyprogesterone caproate. Nearly two-thirds of the women (N=267) began injections ≤ 18 weeks and 394 (92%) received a scheduled weekly injection within 10 days of reaching 35 weeks or delivery. The overall <span class="hlt">rate</span> of <span class="hlt">recurrent</span> preterm birth was 25% (N=106) for the entire cohort compared to the 16.8% expected <span class="hlt">rate</span> (P = 1.0). The three secondary outcomes were also negative. First, 17-alpha hydroxyprogesterone caproate did not significantly reduce the <span class="hlt">rates</span> of <span class="hlt">recurrence</span> regardless of prior preterm birth number or sequence. Second, plasma concentrations of 17-alpha hydroxyprogesterone caproate were not different (P=0.17 at 24 weeks; P=0.38 at 32 weeks) between women delivered ≤ 35 weeks and those delivered later</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T31G..03F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T31G..03F"><span><span class="hlt">Earthquake</span>-driven fluid flow <span class="hlt">rates</span> inferred from borehole temperature measurements within the Japan Trench plate boundary fault zone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fulton, P. M.; Brodsky, E. E.</p> <p>2016-12-01</p> <p>Using borehole sub-seafloor temperature measurements, we have recently identified signatures suggestive of <span class="hlt">earthquake</span>-driven fluid pulses within the Japan Trench plate boundary fault zone during a major aftershock sequence. Here we use numerical models to show that these signatures are consistent with time-varying fluid flow <span class="hlt">rates</span> out of permeable zones within the formation into the borehole annulus. In addition, we also identify an apparent time-varying sensitivity of whether suspected fluid pulses occur in response to <span class="hlt">earthquakes</span> of a given magnitude and distance. The results suggest a damage and healing process and therefore provides a mechanism to allow for a disproportionate amount of heat and chemical transport in the short time frame after an <span class="hlt">earthquake</span>. Our observations come from an observatory installed across the main plate boundary fault as part of IODP's Japan Trench Fast Drilling Project (JFAST) following the March 2011 Mw 9.0 Tohoku-oki <span class="hlt">earthquake</span>. It operated from July 2012 - April 2013 during which a Mw 7.3 <span class="hlt">earthquake</span> and numerous aftershocks occurred. High-resolution temperature time series data reveal spatially correlated transients in response to <span class="hlt">earthquakes</span> with distinct patterns interpreted to reflect advection by transient pulses of fluid flow from permeable zones into the borehole annulus. Typical transients involve perturbations over 12 m with increases of 10 mK that build over 0.1 days at shallower depths and decreases at deeper depths. They are consistently centered around 792.5 m below seafloor (mbsf) where a secondary fault and permeable zone have been independently identified within the damage zone above the main plate boundary fault at 820 mbsf . Model simulations suggest transient flow <span class="hlt">rates</span> of up to 10-3m/s from the formation that quickly decrease. Comparison of characteristics of <span class="hlt">earthquakes</span> identified in nearby ocean bottom pressure measurements suggest there is not a clear relationship between fluid pulses and static strain. There</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.9202L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.9202L"><span>Stress Field Variation after the 2001 Skyros <span class="hlt">Earthquake</span>, Greece, Derived from Seismicity <span class="hlt">Rate</span> Changes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leptokaropoulos, K.; Papadimitriou, E.; Orlecka-Sikora, B.; Karakostas, V.</p> <p>2012-04-01</p> <p>The spatial variation of the stress field (ΔCFF) after the 2001 strong (Mw=6.4) Skyros <span class="hlt">earthquake</span> in North Aegean Sea, Greece, is investigated in association with the changes of <span class="hlt">earthquake</span> production <span class="hlt">rates</span>. A detailed slip model is considered in which the causative fault is consisted of several sub-faults with different coseismic slip onto each one of them. First the spatial distribution of aftershock productivity is compared with the static stress changes due to the coseismic slip. Calculations of ΔCFF are performed at different depths inside the seismogenic layer, defined from the vertical distribution of the aftershocks. Seismicity <span class="hlt">rates</span> of the smaller magnitude events with M≥Mc for different time increments before and after the main shock are then derived from the application of a Probability Density Function (PDF). These <span class="hlt">rates</span> are computed by spatially smoothing the seismicity and for this purpose a normal grid of rectangular cells is superimposed onto the area and the PDF determines seismicity <span class="hlt">rate</span> values at the center of each cell. The differences between the <span class="hlt">earthquake</span> occurrence <span class="hlt">rates</span> before and after the main shock are compared and used as input data in a stress inversion algorithm based upon the <span class="hlt">Rate</span>/State dependent friction concept in order to provide an independent estimation of stress changes. This model incorporates the physical properties of the fault zones (characteristic relaxation time, fault constitutive parameters, effective friction coefficient) with a probabilistic estimation of the spatial distribution of seismicity <span class="hlt">rates</span>, derived from the application of the PDF. The stress patterns derived from the previously mentioned approaches are compared and the quantitative correlation between the respective results is accomplished by the evaluation of Pearson linear correlation coefficient and its confidence intervals to quantify their significance. Different assumptions and combinations of the physical and statistical parameters are tested for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.S41A1892Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.S41A1892Z"><span>Uranium/Thorium Dating and Growth Laminae Counting of Stalagmites Reveal a Record of Major <span class="hlt">Earthquakes</span> in the Midwestern US</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Z.; Lundstrom, C.; Panno, S.; Hackley, K. C.; Fouke, B. W.; Curry, B.</p> <p>2009-12-01</p> <p>The <span class="hlt">recurrence</span> interval of large New Madrid Seismic Zone (NMSZ) <span class="hlt">earthquakes</span> is uncertain because of the limited number and likely incomplete nature of the record of dated seismic events. Data on paleoseismicity in this area is necessary for refining estimates of a <span class="hlt">recurrence</span> interval for these <span class="hlt">earthquakes</span> and for characterizing the geophysical nature of the NMSZ. Studies of the paleoseismic history of the NMSZ have previously used liquefaction features and flood plain deposits along the Mississippi River to estimate <span class="hlt">recurrence</span> interval with considerable uncertainties. More precise estimates of the number and ages of paleoseismic events would enhance the ability of federal, state, and local agencies to make critical preparedness decisions. Initiation of new speleothems (cave deposits) has been shown in several localities to record large <span class="hlt">earthquake</span> events. Our ongoing work in caves of southwestern Illinois, Missouri, Indiana and Arkansas has used both U/Th age dating techniques and growth laminae counting of actively growing stalagmites to determine the age of initiation of stalagmites in caves across the Midwestern U.S. These age initiations cluster around two known events, the great NMSZ <span class="hlt">earthquakes</span> of 1811-1812 and the Missouri <span class="hlt">earthquake</span> of 1917, suggesting that cave deposits in this region constitute a unique record of paleo-seismic history of the NMSZ. Furthermore, the U-Th disequilibria growth laminae ages of young, white stalagmites and of older stalagmites on which they grew, plus published Holocene stalagmite ages of initiation and regrowth from Missouri caves, are all coincident with suspected NMSZ <span class="hlt">earthquakes</span> based on liquefaction and other paleoseimic techniques. We hypothesize that these speleothems were initiated by <span class="hlt">earthquake</span>-induced opening/closing of fracture-controlled flowpaths in the ceilings of cave passages.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28059915','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28059915"><span>Bio-Thiersch as an Adjunct to Perineal Proctectomy Reduces <span class="hlt">Rates</span> of <span class="hlt">Recurrent</span> Rectal Prolapse.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eftaiha, Saleh M; Calata, Jed F; Sugrue, Jeremy J; Marecik, Slawomir J; Prasad, Leela M; Mellgren, Anders; Nordenstam, Johan; Park, John J</p> <p>2017-02-01</p> <p>The <span class="hlt">rates</span> of <span class="hlt">recurrent</span> prolapse after perineal proctectomy vary widely in the literature, with incidences ranging between 0% and 50%. The Thiersch procedure, first described in 1891 for the treatment of rectal prolapse, involves encircling the anus with a foreign material with the goal of confining the prolapsing rectum above the anus. The Bio-Thiersch procedure uses biological mesh for anal encirclement and can be used as an adjunct to perineal proctectomy for rectal prolapse to reduce <span class="hlt">recurrence</span>. The aim of this study was to evaluate the Bio-Thiersch procedure as an adjunct to perineal proctectomy and its impact on <span class="hlt">recurrence</span> compared with perineal proctectomy alone. A retrospective review of consecutive patients undergoing perineal proctectomy with and without Bio-Thiersch was performed. Procedures took place in the Division of Colon and Rectal Surgery at a tertiary academic teaching hospital. Patients who had undergone perineal proctectomy and those who received perineal proctectomy with Bio-Thiersch were evaluated and compared. All of the patients with rectal prolapse received perineal proctectomy with levatorplasty, and a proportion of those patients had a Bio-Thiersch placed as an adjunct. The incidence of <span class="hlt">recurrent</span> rectal prolapse after perineal proctectomy alone or perineal proctectomy with Bio-Thiersch was documented. Sixty-two patients underwent perineal proctectomy (8 had a previous prolapse procedure), and 25 patients underwent perineal proctectomy with Bio-Thiersch (12 had a previous prolapse procedure). Patients who received perineal proctectomy with Bio-Thiersch had a lower <span class="hlt">rate</span> of <span class="hlt">recurrent</span> rectal prolapse (p < 0.05) despite a higher proportion of them having had a previous prolapse procedure (p < 0.01). Perineal proctectomy with Bio-Thiersch had a lower <span class="hlt">recurrence</span> over time versus perineal proctectomy alone (p < 0.05). This study was limited by nature of being a retrospective review. Bio-Thiersch as an adjunct to perineal proctectomy may reduce</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S11B0578G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S11B0578G"><span>Conditional Probabilities of Large <span class="hlt">Earthquake</span> Sequences in California from the Physics-based Rupture Simulator RSQSim</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gilchrist, J. J.; Jordan, T. H.; Shaw, B. E.; Milner, K. R.; Richards-Dinger, K. B.; Dieterich, J. H.</p> <p>2017-12-01</p> <p>Within the SCEC Collaboratory for Interseismic Simulation and Modeling (CISM), we are developing physics-based forecasting models for <span class="hlt">earthquake</span> ruptures in California. We employ the 3D boundary element code RSQSim (<span class="hlt">Rate</span>-State <span class="hlt">Earthquake</span> Simulator of Dieterich & Richards-Dinger, 2010) to generate synthetic catalogs with tens of millions of events that span up to a million years each. This code models rupture nucleation by <span class="hlt">rate</span>- and state-dependent friction and Coulomb stress transfer in complex, fully interacting fault systems. The Uniform California <span class="hlt">Earthquake</span> Rupture Forecast Version 3 (UCERF3) fault and deformation models are used to specify the fault geometry and long-term slip <span class="hlt">rates</span>. We have employed the Blue Waters supercomputer to generate long catalogs of simulated California seismicity from which we calculate the forecasting statistics for large events. We have performed probabilistic seismic hazard analysis with RSQSim catalogs that were calibrated with system-wide parameters and found a remarkably good agreement with UCERF3 (Milner et al., this meeting). We build on this analysis, comparing the conditional probabilities of sequences of large events from RSQSim and UCERF3. In making these comparisons, we consider the epistemic uncertainties associated with the RSQSim parameters (e.g., <span class="hlt">rate</span>- and state-frictional parameters), as well as the effects of model-tuning (e.g., adjusting the RSQSim parameters to match UCERF3 <span class="hlt">recurrence</span> <span class="hlt">rates</span>). The comparisons illustrate how physics-based rupture simulators might assist forecasters in understanding the short-term hazards of large aftershocks and multi-event sequences associated with complex, multi-fault ruptures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/5291961-late-quaternary-history-owens-valley-fault-zone-eastern-california-surface-rupture-associated-earthquake','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/5291961-late-quaternary-history-owens-valley-fault-zone-eastern-california-surface-rupture-associated-earthquake"><span>Late Quaternary history of the Owens Valley fault zone, eastern California, and surface rupture associated with the 1872 <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Beanland, S.; Clark, M.M.</p> <p>1993-04-01</p> <p>The right-lateral Owens Valley fault zone (OVFZ) in eastern California extends north about 100 km from near the northwest shore of Owens Lake to beyond Big Pine. It passes through Lone Pine near the eastern base of the Alabama Hills and follows the floor of Owens Valley northward to the Poverty Hills, where it steps 3 km to the left and continues northwest across Crater Mountain and through Big Pine. Data from one site suggest an average net slip <span class="hlt">rate</span> for the OVFZ of 1.5 [+-] 1 mm/yr for the past 300 ky. Several other sites yield an average Holocenemore » net slip <span class="hlt">rate</span> of 2 [+-] 1 mm/yr. The OVFZ apparently has experienced three major Holocene <span class="hlt">earthquakes</span>. The minimum average <span class="hlt">recurrence</span> interval is 5,000 years at the subsidiary Lone Pine fault, whereas it is 3,300 to 5,000 years elsewhere along the OVFZ. The prehistoric <span class="hlt">earthquakes</span> are not dated, so an average <span class="hlt">recurrence</span> interval need not apply. However, roughly equal (characteristic) displacement apparently happened during each Holocene <span class="hlt">earthquake</span>. The Owens Valley fault zone accommodates some of the relative motion (dextral shear) between the North American and Pacific plates along a discrete structure. This shear occurs in the Walker Lane belt of normal and strike-slip faults within the mainly extensional Basin and Range Province. In Owens Valley displacement is partitioned between the OVFZ and the nearby, subparallel, and purely normal range-front faults of the Sierra Nevada. Compared to the OVFZ, these range-front normal faults are very discontinuous and have smaller Holocene slip <span class="hlt">rates</span> of 0.1 to 0.8 mm/yr, dip slip. Contemporary activity on adjacent faults of such contrasting styles suggests large temporal fluctuations in the relative magnitudes of the maximum and intermediate principal stresses while the extension direction remains consistently east-west.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28285056','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28285056"><span>Unilateral Salpingectomy and Methotrexate Are Associated With a Similar <span class="hlt">Recurrence</span> <span class="hlt">Rate</span> of Ectopic Pregnancy in Patients Undergoing In Vitro Fertilization.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Irani, Mohamad; Robles, Alex; Gunnala, Vinay; Spandorfer, Steven D</p> <p></p> <p>To determine whether different treatment approaches of ectopic pregnancy (EP), particularly unilateral salpingectomy and methotrexate, affect its <span class="hlt">recurrence</span> <span class="hlt">rate</span> in patients undergoing in vitro fertilization (IVF). A retrospective cohort study (Canadian Task Force classification II-2). An academic medical center. Patients with a history of a previous EP who achieved pregnancy after IVF cycles between January 2004 and August 2015 were included. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> of EP was compared between patients who underwent different treatment approaches for a previous EP. IVF. A total of 594 patients were included. Seventeen patients had a <span class="hlt">recurrence</span> of EP (2.9%). Patients with a history of ≥2 EPs were associated with a significantly higher <span class="hlt">recurrence</span> <span class="hlt">rate</span> of EP than those with 1 previous EP (8.5% vs. 1.8%; p = .01; odds ratio [OR] = 2.2; 95% confidence interval [CI], 1.2-4.4). Patients who underwent unilateral salpingectomy (n = 245) had a comparable <span class="hlt">recurrence</span> <span class="hlt">rate</span> of EP after IVF with those who received methotrexate (n = 283) (3.6% vs. 2.8%; p = .5; OR = 1.3; 95% CI, 0.4-3.4). This OR remained unchanged after adjusting for patient's age, number of previous EPs, number of transferred embryos, and peak estradiol level during stimulation (adjusted OR = 1.4; 95% CI, 0.5-3.8). None of the patients who underwent bilateral salpingectomy (n = 45) or salpingostomy (n = 21) had a <span class="hlt">recurrence</span> of EP after IVF. The <span class="hlt">recurrence</span> <span class="hlt">rate</span> of EP significantly correlates with the number of previous EPs. Treatment of EP with methotrexate has a comparable <span class="hlt">recurrence</span> <span class="hlt">rate</span> of EP after IVF with unilateral salpingectomy. Therefore, the risk of <span class="hlt">recurrence</span> should not be a reason to favor salpingectomy over methotrexate in this population. Copyright © 2017 AAGL. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70191859','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70191859"><span>Ground-rupturing <span class="hlt">earthquakes</span> on the northern Big Bend of the San Andreas Fault, California, 800 A.D. to Present</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Scharer, Katherine M.; Weldon, Ray; Biasi, Glenn; Streig, Ashley; Fumal, Thomas E.</p> <p>2017-01-01</p> <p>Paleoseismic data on the timing of ground-rupturing <span class="hlt">earthquakes</span> constrain the <span class="hlt">recurrence</span> behavior of active faults and can provide insight on the rupture history of a fault if <span class="hlt">earthquakes</span> dated at neighboring sites overlap in age and are considered correlative. This study presents the evidence and ages for 11 <span class="hlt">earthquakes</span> that occurred along the Big Bend section of the southern San Andreas Fault at the Frazier Mountain paleoseismic site. The most recent <span class="hlt">earthquake</span> to rupture the site was the Mw7.7–7.9 Fort Tejon <span class="hlt">earthquake</span> of 1857. We use over 30 trench excavations to document the structural and sedimentological evolution of a small pull-apart basin that has been repeatedly faulted and folded by ground-rupturing <span class="hlt">earthquakes</span>. A sedimentation <span class="hlt">rate</span> of 0.4 cm/yr and abundant organic material for radiocarbon dating contribute to a record that is considered complete since 800 A.D. and includes 10 paleoearthquakes. <span class="hlt">Earthquakes</span> have ruptured this location on average every ~100 years over the last 1200 years, but individual intervals range from ~22 to 186 years. The coefficient of variation of the length of time between <span class="hlt">earthquakes</span> (0.7) indicates quasiperiodic behavior, similar to other sites along the southern San Andreas Fault. Comparison with the <span class="hlt">earthquake</span> chronology at neighboring sites along the fault indicates that only one other 1857-size <span class="hlt">earthquake</span> could have occurred since 1350 A.D., and since 800 A.D., the Big Bend and Mojave sections have ruptured together at most 50% of the time in Mw ≥ 7.3 <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS21G..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS21G..01M"><span>Direct and indirect evidence for <span class="hlt">earthquakes</span>; an example from the Lake Tahoe Basin, California-Nevada</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maloney, J. M.; Noble, P. J.; Driscoll, N. W.; Kent, G.; Schmauder, G. C.</p> <p>2012-12-01</p> <p>High-resolution seismic CHIRP data can image direct evidence of <span class="hlt">earthquakes</span> (i.e., offset strata) beneath lakes and the ocean. Nevertheless, direct evidence often is not imaged due to conditions such as gas in the sediments, or steep basement topography. In these cases, indirect evidence for <span class="hlt">earthquakes</span> (i.e., debris flows) may provide insight into the paleoseismic record. The four sub-basins of the tectonically active Lake Tahoe Basin provide an ideal opportunity to image direct evidence for <span class="hlt">earthquake</span> deformation and compare it to indirect <span class="hlt">earthquake</span> proxies. We present results from high-resolution seismic CHIRP surveys in Emerald Bay, Fallen Leaf Lake, and Cascade Lake to constrain the <span class="hlt">recurrence</span> interval on the West Tahoe Dollar Point Fault (WTDPF), which was previously identified as potentially the most hazardous fault in the Lake Tahoe Basin. Recently collected CHIRP profiles beneath Fallen Leaf Lake image slide deposits that appear synchronous with slides in other sub-basins. The temporal correlation of slides between multiple basins suggests triggering by events on the WTDPF. If correct, we postulate a <span class="hlt">recurrence</span> interval for the WTDPF of ~3-4 k.y., indicating that the WTDPF is near its seismic <span class="hlt">recurrence</span> cycle. In addition, CHIRP data beneath Cascade Lake image strands of the WTDPF that offset the lakefloor as much as ~7 m. The Cascade Lake data combined with onshore LiDAR allowed us to map the geometry of the WTDPF continuously across the southern Lake Tahoe Basin and yielded an improved geohazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/20641368-time-decreasing-hazard-increasing-time-until-next-earthquake','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/20641368-time-decreasing-hazard-increasing-time-until-next-earthquake"><span>Time-decreasing hazard and increasing time until the next <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Corral, Alvaro</p> <p>2005-01-01</p> <p>The existence of a slowly always decreasing probability density for the <span class="hlt">recurrence</span> times of <span class="hlt">earthquakes</span> in the stationary case implies that the occurrence of an event at a given instant becomes more unlikely as time since the previous event increases. Consequently, the expected waiting time to the next <span class="hlt">earthquake</span> increases with the elapsed time, that is, the event moves away fast to the future. We have found direct empirical evidence of this counterintuitive behavior in two worldwide catalogs as well as in diverse regional catalogs. Universal scaling functions describe the phenomenon well.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.6648E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.6648E"><span>Turkish Compulsory <span class="hlt">Earthquake</span> Insurance (TCIP)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Erdik, M.; Durukal, E.; Sesetyan, K.</p> <p>2009-04-01</p> <p>Through a World Bank project a government-sponsored Turkish Catastrophic Insurance Pool (TCIP) is created in 2000 with the essential aim of transferring the government's financial burden of replacing <span class="hlt">earthquake</span>-damaged housing to international reinsurance and capital markets. Providing coverage to about 2.9 Million homeowners TCIP is the largest insurance program in the country with about 0.5 Billion USD in its own reserves and about 2.3 Billion USD in total claims paying capacity. The total payment for <span class="hlt">earthquake</span> damage since 2000 (mostly small, 226 <span class="hlt">earthquakes</span>) amounts to about 13 Million USD. The country-wide penetration <span class="hlt">rate</span> is about 22%, highest in the Marmara region (30%) and lowest in the south-east Turkey (9%). TCIP is the sole-source provider of <span class="hlt">earthquake</span> loss coverage up to 90,000 USD per house. The annual premium, categorized on the basis of <span class="hlt">earthquake</span> zones type of structure, is about US90 for a 100 square meter reinforced concrete building in the most hazardous zone with 2% deductible. The <span class="hlt">earthquake</span> engineering related shortcomings of the TCIP is exemplified by fact that the average <span class="hlt">rate</span> of 0.13% (for reinforced concrete buildings) with only 2% deductible is rather low compared to countries with similar <span class="hlt">earthquake</span> exposure. From an <span class="hlt">earthquake</span> engineering point of view the risk underwriting (Typification of housing units to be insured, <span class="hlt">earthquake</span> intensity zonation and the sum insured) of the TCIP needs to be overhauled. Especially for large cities, models can be developed where its expected <span class="hlt">earthquake</span> performance (and consequently the insurance premium) can be can be assessed on the basis of the location of the unit (microzoned <span class="hlt">earthquake</span> hazard) and basic structural attributes (<span class="hlt">earthquake</span> vulnerability relationships). With such an approach, in the future the TCIP can contribute to the control of construction through differentiation of premia on the basis of <span class="hlt">earthquake</span> vulnerability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25338317','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25338317"><span>Changes in suicide <span class="hlt">rates</span> in disaster-stricken areas following the Great East Japan <span class="hlt">Earthquake</span> and their effect on economic factors: an ecological study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Orui, Masatsugu; Harada, Shuichiro; Hayashi, Mizuho</p> <p>2014-11-01</p> <p>Devastating disasters may increase suicide <span class="hlt">rates</span> due to mental distress. Previous domestic studies have reported decreased suicide <span class="hlt">rates</span> among men following disasters. Few reports are available regarding factors associated with disasters, making it difficult to discuss how these events affect suicide <span class="hlt">rates</span>. This study aimed to observe changes in suicide <span class="hlt">rates</span> in disaster-stricken and neighboring areas following the Great East Japan <span class="hlt">Earthquake</span>, and examine associations between suicide <span class="hlt">rates</span> and economic factors. Monthly suicide <span class="hlt">rates</span> were observed from March 2009 to February 2013, during which time the <span class="hlt">earthquake</span> occurred on March, 2011. Data were included from disaster-stricken (Iwate, Miyagi, and Fukushima Prefectures) and neighboring (control: Aomori, Akita, and Yamagata Prefectures) areas. The association between changes in suicide <span class="hlt">rates</span> and economic variables was evaluated based on the number of bankruptcy cases and ratio of effective job offers. In disaster-stricken areas, post-disaster male suicide <span class="hlt">rates</span> decreased during the 24 months following the <span class="hlt">earthquake</span>. This trend differed relative to control areas. Female suicide <span class="hlt">rates</span> increased during the first seven months. Multiple regression analysis showed that bankruptcy cases (β = 0.386, p = 0.038) and ratio of effective job offers (β = -0.445, p = 0.018) were only significantly associated with male post-disaster suicide <span class="hlt">rates</span> in control areas. Post-disaster suicide <span class="hlt">rates</span> differed by gender following the <span class="hlt">earthquake</span>. Our findings suggest that considering gender differences might be important for developing future post-disaster suicide prevention measures. This ecological study revealed that increasing effective job offers and decreasing bankruptcy cases can affect protectively male suicide <span class="hlt">rates</span> in control areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70188387','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70188387"><span>Accelerating slip <span class="hlt">rates</span> on the puente hills blind thrust fault system beneath metropolitan Los Angeles, California, USA</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bergen, Kristian J.; Shaw, John H.; Leon, Lorraine A.; Dolan, James F.; Pratt, Thomas L.; Ponti, Daniel J.; Morrow, Eric; Barrera, Wendy; Rhodes, Edward J.; Murari, Madhav K.; Owen, Lewis A.</p> <p>2017-01-01</p> <p>Slip <span class="hlt">rates</span> represent the average displacement across a fault over time and are essential to estimating <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> for proba-bilistic seismic hazard assessments. We demonstrate that the slip <span class="hlt">rate</span> on the western segment of the Puente Hills blind thrust fault system, which is beneath downtown Los Angeles, California (USA), has accel-erated from ~0.22 mm/yr in the late Pleistocene to ~1.33 mm/yr in the Holocene. Our analysis is based on syntectonic strata derived from the Los Angeles River, which has continuously buried a fold scarp above the blind thrust. Slip on the fault beneath our field site began during the late-middle Pleistocene and progressively increased into the Holocene. This increase in <span class="hlt">rate</span> implies that the magnitudes and/or the frequency of <span class="hlt">earthquakes</span> on this fault segment have increased over time. This challenges the characteristic <span class="hlt">earthquake</span> model and presents an evolving and potentially increasing seismic hazard to metropolitan Los Angeles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70033423','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70033423"><span>Effects of acoustic waves on stick-slip in granular media and implications for <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Johnson, P.A.; Savage, H.; Knuth, M.; Gomberg, J.; Marone, Chris</p> <p>2008-01-01</p> <p>It remains unknown how the small strains induced by seismic waves can trigger <span class="hlt">earthquakes</span> at large distances, in some cases thousands of kilometres from the triggering <span class="hlt">earthquake</span>, with failure often occurring long after the waves have passed. <span class="hlt">Earthquake</span> nucleation is usually observed to take place at depths of 10-20 km, and so static overburden should be large enough to inhibit triggering by seismic-wave stress perturbations. To understand the physics of dynamic triggering better, as well as the influence of dynamic stressing on <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>, we have conducted laboratory studies of stick-slip in granular media with and without applied acoustic vibration. Glass beads were used to simulate granular fault zone material, sheared under constant normal stress, and subject to transient or continuous perturbation by acoustic waves. Here we show that small-magnitude failure events, corresponding to triggered aftershocks, occur when applied sound-wave amplitudes exceed several microstrain. These events are frequently delayed or occur as part of a cascade of small events. Vibrations also cause large slip events to be disrupted in time relative to those without wave perturbation. The effects are observed for many large-event cycles after vibrations cease, indicating a strain memory in the granular material. Dynamic stressing of tectonic faults may play a similar role in determining the complexity of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. ??2007 Nature Publishing Group.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/pp/1360/report.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/pp/1360/report.pdf"><span>Evaluating <span class="hlt">earthquake</span> hazards in the Los Angeles region; an earth-science perspective</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Ziony, Joseph I.</p> <p>1985-01-01</p> <p>Potentially destructive <span class="hlt">earthquakes</span> are inevitable in the Los Angeles region of California, but hazards prediction can provide a basis for reducing damage and loss. This volume identifies the principal geologically controlled <span class="hlt">earthquake</span> hazards of the region (surface faulting, strong shaking, ground failure, and tsunamis), summarizes methods for characterizing their extent and severity, and suggests opportunities for their reduction. Two systems of active faults generate <span class="hlt">earthquakes</span> in the Los Angeles region: northwest-trending, chiefly horizontal-slip faults, such as the San Andreas, and west-trending, chiefly vertical-slip faults, such as those of the Transverse Ranges. Faults in these two systems have produced more than 40 damaging <span class="hlt">earthquakes</span> since 1800. Ninety-five faults have slipped in late Quaternary time (approximately the past 750,000 yr) and are judged capable of generating future moderate to large <span class="hlt">earthquakes</span> and displacing the ground surface. Average <span class="hlt">rates</span> of late Quaternary slip or separation along these faults provide an index of their relative activity. The San Andreas and San Jacinto faults have slip <span class="hlt">rates</span> measured in tens of millimeters per year, but most other faults have <span class="hlt">rates</span> of about 1 mm/yr or less. Intermediate <span class="hlt">rates</span> of as much as 6 mm/yr characterize a belt of Transverse Ranges faults that extends from near Santa Barbara to near San Bernardino. The dimensions of late Quaternary faults provide a basis for estimating the maximum sizes of likely future <span class="hlt">earthquakes</span> in the Los Angeles region: moment magnitude .(M) 8 for the San Andreas, M 7 for the other northwest-trending elements of that fault system, and M 7.5 for the Transverse Ranges faults. Geologic and seismologic evidence along these faults, however, suggests that, for planning and designing noncritical facilities, appropriate sizes would be M 8 for the San Andreas, M 7 for the San Jacinto, M 6.5 for other northwest-trending faults, and M 6.5 to 7 for the Transverse Ranges faults. The</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70025540','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70025540"><span>Intraplate triggered <span class="hlt">earthquakes</span>: Observations and interpretation</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hough, S.E.; Seeber, L.; Armbruster, J.G.</p> <p>2003-01-01</p> <p>We present evidence that at least two of the three 1811-1812 New Madrid, central United States, mainshocks and the 1886 Charleston, South Carolina, <span class="hlt">earthquake</span> triggered <span class="hlt">earthquakes</span> at regional distances. In addition to previously published evidence for triggered <span class="hlt">earthquakes</span> in the northern Kentucky/southern Ohio region in 1812, we present evidence suggesting that triggered events might have occurred in the Wabash Valley, to the south of the New Madrid Seismic Zone, and near Charleston, South Carolina. We also discuss evidence that <span class="hlt">earthquakes</span> might have been triggered in northern Kentucky within seconds of the passage of surface waves from the 23 January 1812 New Madrid mainshock. After the 1886 Charleston <span class="hlt">earthquake</span>, accounts suggest that triggered events occurred near Moodus, Connecticut, and in southern Indiana. Notwithstanding the uncertainty associated with analysis of historical accounts, there is evidence that at least three out of the four known Mw 7 <span class="hlt">earthquakes</span> in the central and eastern United States seem to have triggered <span class="hlt">earthquakes</span> at distances beyond the typically assumed aftershock zone of 1-2 mainshock fault lengths. We explore the possibility that remotely triggered <span class="hlt">earthquakes</span> might be common in low-strain-<span class="hlt">rate</span> regions. We suggest that in a low-strain-<span class="hlt">rate</span> environment, permanent, nonelastic deformation might play a more important role in stress accumulation than it does in interplate crust. Using a simple model incorporating elastic and anelastic strain release, we show that, for realistic parameter values, faults in intraplate crust remain close to their failure stress for a longer part of the <span class="hlt">earthquake</span> cycle than do faults in high-strain-<span class="hlt">rate</span> regions. Our results further suggest that remotely triggered <span class="hlt">earthquakes</span> occur preferentially in regions of recent and/or future seismic activity, which suggests that faults are at a critical stress state in only some areas. Remotely triggered <span class="hlt">earthquakes</span> may thus serve as beacons that identify regions of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70003714','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70003714"><span>An empirical model for global <span class="hlt">earthquake</span> fatality estimation</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jaiswal, Kishor; Wald, David</p> <p>2010-01-01</p> <p>We analyzed mortality <span class="hlt">rates</span> of <span class="hlt">earthquakes</span> worldwide and developed a country/region-specific empirical model for <span class="hlt">earthquake</span> fatality estimation within the U.S. Geological Survey's Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER) system. The <span class="hlt">earthquake</span> fatality <span class="hlt">rate</span> is defined as total killed divided by total population exposed at specific shaking intensity level. The total fatalities for a given <span class="hlt">earthquake</span> are estimated by multiplying the number of people exposed at each shaking intensity level by the fatality <span class="hlt">rates</span> for that level and then summing them at all relevant shaking intensities. The fatality <span class="hlt">rate</span> is expressed in terms of a two-parameter lognormal cumulative distribution function of shaking intensity. The parameters are obtained for each country or a region by minimizing the residual error in hindcasting the total shaking-related deaths from <span class="hlt">earthquakes</span> recorded between 1973 and 2007. A new global regionalization scheme is used to combine the fatality data across different countries with similar vulnerability traits.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22939327','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22939327"><span>Idiopathic bone cavities of the mandible: an update on <span class="hlt">recurrence</span> <span class="hlt">rates</span> and case report.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Horne, Robert P; Meara, Daniel J; Granite, Edwin L</p> <p>2014-02-01</p> <p>Idiopathic bone cavities (IBCs) are usually an incidental finding, often found in long bones but also in the craniofacial skeleton. Typically solitary, IBCs can present at multiple sites. Surgical exploration alone has proved effective, although <span class="hlt">recurrence</span> does occur, particularly in cases with multiple lesions. The average time necessary to observe either <span class="hlt">recurrence</span> or complete healing has been reported to be more than 3 years. Previously reported low <span class="hlt">recurrence</span> <span class="hlt">rates</span> for IBCs in the craniofacial skeleton may have been artificially low because of insufficient long-term follow-up. Providers should be prepared for long-term follow-up and care of these patients. The case of the patient presented here supports the need for long-term follow-up. Copyright © 2014 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23070583','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23070583"><span>Importance of <span class="hlt">recurrence</span> <span class="hlt">rating</span>, morphology, hernial gap size, and risk factors in ventral and incisional hernia classification.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dietz, U A; Winkler, M S; Härtel, R W; Fleischhacker, A; Wiegering, A; Isbert, C; Jurowich, Ch; Heuschmann, P; Germer, C-T</p> <p>2014-02-01</p> <p>There is limited evidence on the natural course of ventral and incisional hernias and the results of hernia repair, what might partially be explained by the lack of an accepted classification system. The aim of the present study is to investigate the association of the criteria included in the Wuerzburg classification system of ventral and incisional hernias with postoperative complications and long-term <span class="hlt">recurrence</span>. In a retrospective cohort study, the data on 330 consecutive patients who underwent surgery to repair ventral and incisional hernias were analyzed. The following four classification criteria were applied: (a) <span class="hlt">recurrence</span> <span class="hlt">rating</span> (ventral, incisional or incisional <span class="hlt">recurrent</span>); (b) morphology (location); (c) size of the hernial gap; and (d) risk factors. The primary endpoint was the occurrence of a <span class="hlt">recurrence</span> during follow-up. Secondary endpoints were incidence of postoperative complications. Independent association between classification criteria, type of surgical procedures and postoperative complications was calculated by multivariate logistic regression analysis and between classification criteria, type of surgical procedures and risk of long-term <span class="hlt">recurrence</span> by Cox regression analysis. Follow-up lasted a mean 47.7 ± 23.53 months (median 45 months) or 3.9 ± 1.96 years. The criterion "<span class="hlt">recurrence</span> <span class="hlt">rating</span>" was found as predictive factor for postoperative complications in the multivariate analysis (OR 2.04; 95 % CI 1.09-3.84; incisional vs. ventral hernia). The criterion "morphology" had influence neither on the incidence of the critical event "<span class="hlt">recurrence</span> during follow-up" nor on the incidence of postoperative complications. Hernial gap "width" predicted postoperative complications in the multivariate analysis (OR 1.98; 95 % CI 1.19-3.29; ≤5 vs. >5 cm). Length of the hernial gap was found to be an independent prognostic factor for the critical event "<span class="hlt">recurrence</span> during follow-up" (HR 2.05; 95 % CI 1.25-3.37; ≤5 vs. >5 cm). The presence of 3 or more risk</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017OGeo....9....4P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017OGeo....9....4P"><span>Probabilities of <span class="hlt">Earthquake</span> Occurrences along the Sumatra-Andaman Subduction Zone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pailoplee, Santi</p> <p>2017-03-01</p> <p><span class="hlt">Earthquake</span> activities along the Sumatra-Andaman Subduction Zone (SASZ) were clarified using the derived frequency-magnitude distribution in terms of the (i) most probable maximum magnitudes, (ii) return periods and (iii) probabilities of <span class="hlt">earthquake</span> occurrences. The northern segment of SASZ, along the western coast of Myanmar to southern Nicobar, was found to be capable of generating an <span class="hlt">earthquake</span> of magnitude 6.1-6.4 Mw in the next 30-50 years, whilst the southern segment of offshore of the northwestern and western parts of Sumatra (defined as a high hazard region) had a short <span class="hlt">recurrence</span> interval of 6-12 and 10-30 years for a 6.0 and 7.0 Mw magnitude <span class="hlt">earthquake</span>, respectively, compared to the other regions. Throughout the area along the SASZ, there are 70- almost 100% probabilities of the <span class="hlt">earthquake</span> with Mw up to 6.0 might be generated in the next 50 years whilst the northern segment had less than 50% chance of occurrence of a 7.0 Mw <span class="hlt">earthquake</span> in the next 50 year. Although Rangoon was defined as the lowest hazard among the major city in the vicinity of SASZ, there is 90% chance of a 6.0 Mw <span class="hlt">earthquake</span> in the next 50 years. Therefore, the effective mitigation plan of seismic hazard should be contributed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S41C0781M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S41C0781M"><span><span class="hlt">Earthquake</span> sequence simulations of a fault in a viscoelastic material with a spectral boundary integral equation method: The effect of interseismic stress relaxation on a behavior of a <span class="hlt">rate</span>-weakening patch</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miyake, Y.; Noda, H.</p> <p>2017-12-01</p> <p><span class="hlt">Earthquake</span> sequences involve many processes in a wide range of time scales, from quasistatic loading to dynamic rupture. At a depth of brittle-plastic transitional and deeper, rock behaves as a viscous fluid in a long timescale, but as an elastic material in a short timescale. Viscoelastic stress relaxation may be important in the interseismic periods at the depth, near the deeper limit of the seismogenic layer or the region of slow slip events (SSEs) [Namiki et al., 2014 and references therein]. In the present study, we implemented the viscoelastic effect (Maxwell material) in fully-dynamic <span class="hlt">earthquake</span> sequence simulations using a spectral boundary integral equation method (SBIEM) [e.g., Lapusta et al., 2000]. SBIEM is efficient in calculation of convolutional terms for dynamic stress transfer, and the problem size is limited by the amount of memory available. Linear viscoelasticity could be implemented by convolution of slip <span class="hlt">rate</span> history and Green's function, but this method requires additional memory and thus not suitable for the implementation to the present code. Instead, we integrated the evolution of "effective slip" distribution, which gives static stress distribution when convolved with static elastic Green's function. This method works only for simple viscoelastic property distributions, but such models are suitable for numerical experiments aiming basic understanding of the system behavior because of the virtue of SBIEM, the ability of fine on-fault spatial resolution and efficient computation utilizing the fast Fourier transformation. In the present study, we examined the effect of viscoelasticity on <span class="hlt">earthquake</span> sequences of a fault with a <span class="hlt">rate</span>-weakening patch. A series of simulations with various relaxation time tc revealed that as decreasing tc, <span class="hlt">recurrence</span> intervals of <span class="hlt">earthquakes</span> increases and seismicity ultimately disappears. As long as studied, this transition to aseismic behavior is NOT associated with SSEs. In a case where the <span class="hlt">rate</span>-weakening patch</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.jstor.org/stable/2881298','USGSPUBS'); return false;" href="http://www.jstor.org/stable/2881298"><span>Near-field investigations of the Landers <span class="hlt">earthquake</span> sequence, April to July 1992</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Sieh, K.; Jones, L.; Hauksson, E.; Hudnut, K.; Eberhart-Phillips, D.; Heaton, T.; Hough, S.; Hutton, K.; Kanamori, H.; Lilje, A.; Lindvall, Scott; McGill, S.F.; Mori, J.; Rubin, C.; Spotila, J.A.; Stock, J.; Thio, H.K.; Treiman, J.; Wernicke, B.; Zachariasen, J.</p> <p>1993-01-01</p> <p>The Landers <span class="hlt">earthquake</span>, which had a moment magnitude (Mw) of 7.3, was the largest <span class="hlt">earthquake</span> to strike the contiguous United States in 40 years. This <span class="hlt">earthquake</span> resulted from the rupture of five major and many minor right-lateral faults near the southern end of the eastern California shear zone, just north of the San Andreas fault. Its Mw 6.1 preshock and Mw 6.2 aftershock had their own aftershocks and foreshocks. Surficial geological observations are consistent with local and far-field seismologic observations of the <span class="hlt">earthquake</span>. Large surficial offsets (as great as 6 meters) and a relatively short rupture length (85 kilometers) are consistent with seismological calculations of a high stress drop (200 bars), which is in turn consistent with an apparently long <span class="hlt">recurrence</span> interval for these faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH21A1812Q','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH21A1812Q"><span><span class="hlt">Earthquake</span> Forecasting Through Semi-periodicity Analysis of Labeled Point Processes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Quinteros Cartaya, C. B. M.; Nava Pichardo, F. A.; Glowacka, E.; Gomez-Trevino, E.</p> <p>2015-12-01</p> <p>Large <span class="hlt">earthquakes</span> have semi-periodic behavior as result of critically self-organized processes of stress accumulation and release in some seismogenic region. Thus, large <span class="hlt">earthquakes</span> in a region constitute semi-periodic sequences with <span class="hlt">recurrence</span> times varying slightly from periodicity. Nava et al., 2013 and Quinteros et al., 2013 realized that not all <span class="hlt">earthquakes</span> in a given region need belong to the same sequence, since there can be more than one process of stress accumulation and release in it; they also proposed a method to identify semi-periodic sequences through analytic Fourier analysis. This work presents improvements on the above-mentioned method: the influence of <span class="hlt">earthquake</span> size on the spectral analysis, and its importance in semi-periodic events identification, which means that <span class="hlt">earthquake</span> occurrence times are treated as a labeled point process; the estimation of appropriate upper limit uncertainties to use in forecasts; and the use of Bayesian analysis to evaluate the forecast performance. This improved method is applied to specific regions: the southwestern coast of Mexico, the northeastern Japan Arc, the San Andreas Fault zone at Parkfield, and northeastern Venezuela.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH33A0239F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH33A0239F"><span>Very High-<span class="hlt">rate</span> (50 Hz) GPS for Detection of <span class="hlt">Earthquake</span> Ground Motions : How High Do We Need to Go?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fang, R.</p> <p>2017-12-01</p> <p>The GPS variometric approach can measure displacements using broadcast ephemeris and a single receiver, with comparable precision to relative positioning and PPP within a short period of time. We evaluate the performance of the variometric approach to measure displacements using very high-<span class="hlt">rate</span> (50 Hz) GPS data, which recorded from the 2013 Mw 6.6 Lushan <span class="hlt">earthquake</span> and the 2011 Mw 9.0 Tohoku-Oki <span class="hlt">earthquake</span>. To remove the nonlinear drift due to integration process, we present to apply a high-pass filter to reconstruct displacements using the variometric approach. Comparison between 50 Hz and 1 Hz coseismic displacements demonstrates that 1 Hz solutions often fail to faithfully manifest the seismic waves containing high-frequency (> 0.5 Hz) seismic signals, which is common for near-field stations during a moderate-magnitude <span class="hlt">earthquake</span>. Therefore, in order to reconstruct near-field seismic waves caused by moderate or large <span class="hlt">earthquakes</span>, it is helpful to equip monitoring stations with very high-<span class="hlt">rate</span> GPS receivers. Results derived using the variometric approach are compared with PPP results. They display very good consistence within only a few millimeters both in static and seismic periods. High-frequency (above 10 Hz) noises of displacements derived using the variometric approach are smaller than PPP displacements in three components.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018EP%26S...70...92K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018EP%26S...70...92K"><span>Kinetic effect of heating <span class="hlt">rate</span> on the thermal maturity of carbonaceous material as an indicator of frictional heat during <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kaneki, Shunya; Hirono, Tetsuro</p> <p>2018-06-01</p> <p>Because the maximum temperature reached in the slip zone is significant information for understanding slip behaviors during an <span class="hlt">earthquake</span>, the maturity of carbonaceous material (CM) is widely used as a proxy for detecting frictional heat recorded by fault rocks. The degree of maturation of CM is controlled not only by maximum temperature but also by the heating <span class="hlt">rate</span>. Nevertheless, maximum slip zone temperature has been estimated previously by comparing the maturity of CM in natural fault rocks with that of synthetic products heated at <span class="hlt">rates</span> of about 1 °C s-1, even though this <span class="hlt">rate</span> is much lower than the actual heating <span class="hlt">rate</span> during an <span class="hlt">earthquake</span>. In this study, we investigated the kinetic effect of the heating <span class="hlt">rate</span> on the CM maturation process by performing organochemical analyses of CM heated at slow (1 °C s-1) and fast (100 °C s-1) <span class="hlt">rates</span>. The results clearly showed that a higher heating <span class="hlt">rate</span> can inhibit the maturation reactions of CM; for example, extinction of aliphatic hydrocarbon chains occurred at 600 °C at a heating <span class="hlt">rate</span> of 1 °C s-1 and at 900 °C at a heating <span class="hlt">rate</span> of 100 °C s-1. However, shear-enhanced mechanochemical effects can also promote CM maturation reactions and may offset the effect of a high heating <span class="hlt">rate</span>. We should thus consider simultaneously the effects of both heating <span class="hlt">rate</span> and mechanochemistry on CM maturation to establish CM as a more rigorous proxy for frictional heat recorded by fault rocks and for estimating slip behaviors during <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..474..312C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..474..312C"><span>A model-free characterization of <span class="hlt">recurrences</span> in stationary time series</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chicheportiche, Rémy; Chakraborti, Anirban</p> <p>2017-05-01</p> <p>Study of <span class="hlt">recurrences</span> in <span class="hlt">earthquakes</span>, climate, financial time-series, etc. is crucial to better forecast disasters and limit their consequences. Most of the previous phenomenological studies of <span class="hlt">recurrences</span> have involved only a long-ranged autocorrelation function, and ignored the multi-scaling properties induced by potential higher order dependencies. We argue that copulas is a natural model-free framework to study non-linear dependencies in time series and related concepts like <span class="hlt">recurrences</span>. Consequently, we arrive at the facts that (i) non-linear dependences do impact both the statistics and dynamics of <span class="hlt">recurrence</span> times, and (ii) the scaling arguments for the unconditional distribution may not be applicable. Hence, fitting and/or simulating the intertemporal distribution of <span class="hlt">recurrence</span> intervals is very much system specific, and cannot actually benefit from universal features, in contrast to the previous claims. This has important implications in epilepsy prognosis and financial risk management applications.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JAESc..67..153Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JAESc..67..153Y"><span>Repeating aftershocks of the great 2004 Sumatra and 2005 Nias <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yu, Wen-che; Song, Teh-Ru Alex; Silver, Paul G.</p> <p>2013-05-01</p> <p>We investigate repeating aftershocks associated with the great 2004 Sumatra-Andaman (Mw 9.2) and 2005 Nias-Simeulue (Mw 8.6) <span class="hlt">earthquakes</span> by cross-correlating waveforms recorded by the regional seismographic station PSI and teleseismic stations. We identify 10 and 18 correlated aftershock sequences associated with the great 2004 Sumatra and 2005 Nias <span class="hlt">earthquakes</span>, respectively. The majority of the correlated aftershock sequences are located near the down-dip end of a large afterslip patch. We determine the precise relative locations of event pairs among these sequences and estimate the source rupture areas. The correlated event pairs identified are appropriately referred to as repeating aftershocks, in that the source rupture areas are comparable and significantly overlap within a sequence. We use the repeating aftershocks to estimate afterslip based on the slip-seismic moment scaling relationship and to infer the temporal decay <span class="hlt">rate</span> of the <span class="hlt">recurrence</span> interval. The estimated afterslip resembles that measured from the near-field geodetic data to the first order. The decay <span class="hlt">rate</span> of repeating aftershocks as a function of lapse time t follows a power-law decay 1/tp with the exponent p in the range 0.8-1.1. Both types of observations indicate that repeating aftershocks are governed by post-seismic afterslip.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70044014','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70044014"><span><span class="hlt">Earthquake</span> casualty models within the USGS Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER) system</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jaiswal, Kishor; Wald, David J.; Earle, Paul S.; Porter, Keith A.; Hearne, Mike</p> <p>2011-01-01</p> <p>Since the launch of the USGS’s Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER) system in fall of 2007, the time needed for the U.S. Geological Survey (USGS) to determine and comprehend the scope of any major <span class="hlt">earthquake</span> disaster anywhere in the world has been dramatically reduced to less than 30 min. PAGER alerts consist of estimated shaking hazard from the ShakeMap system, estimates of population exposure at various shaking intensities, and a list of the most severely shaken cities in the epicentral area. These estimates help government, scientific, and relief agencies to guide their responses in the immediate aftermath of a significant <span class="hlt">earthquake</span>. To account for wide variability and uncertainty associated with inventory, structural vulnerability and casualty data, PAGER employs three different global <span class="hlt">earthquake</span> fatality/loss computation models. This article describes the development of the models and demonstrates the loss estimation capability for <span class="hlt">earthquakes</span> that have occurred since 2007. The empirical model relies on country-specific <span class="hlt">earthquake</span> loss data from past <span class="hlt">earthquakes</span> and makes use of calibrated casualty <span class="hlt">rates</span> for future prediction. The semi-empirical and analytical models are engineering-based and rely on complex datasets including building inventories, time-dependent population distributions within different occupancies, the vulnerability of regional building stocks, and casualty <span class="hlt">rates</span> given structural collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S53A2794B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S53A2794B"><span><span class="hlt">Earthquake</span> Fingerprints: Representing <span class="hlt">Earthquake</span> Waveforms for Similarity-Based Detection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bergen, K.; Beroza, G. C.</p> <p>2016-12-01</p> <p>New <span class="hlt">earthquake</span> detection methods, such as Fingerprint and Similarity Thresholding (FAST), use fast approximate similarity search to identify similar waveforms in long-duration data without templates (Yoon et al. 2015). These methods have two key components: fingerprint extraction and an efficient search algorithm. Fingerprint extraction converts waveforms into fingerprints, compact signatures that represent short-duration waveforms for identification and search. <span class="hlt">Earthquakes</span> are detected using an efficient indexing and search scheme, such as locality-sensitive hashing, that identifies similar waveforms in a fingerprint database. The quality of the search results, and thus the <span class="hlt">earthquake</span> detection results, is strongly dependent on the fingerprinting scheme. Fingerprint extraction should map similar <span class="hlt">earthquake</span> waveforms to similar waveform fingerprints to ensure a high detection <span class="hlt">rate</span>, even under additive noise and small distortions. Additionally, fingerprints corresponding to noise intervals should have mutually dissimilar fingerprints to minimize false detections. In this work, we compare the performance of multiple fingerprint extraction approaches for the <span class="hlt">earthquake</span> waveform similarity search problem. We apply existing audio fingerprinting (used in content-based audio identification systems) and time series indexing techniques and present modified versions that are specifically adapted for seismic data. We also explore data-driven fingerprinting approaches that can take advantage of labeled or unlabeled waveform data. For each fingerprinting approach we measure its ability to identify similar waveforms in a low signal-to-noise setting, and quantify the trade-off between true and false detection <span class="hlt">rates</span> in the presence of persistent noise sources. We compare the performance using known event waveforms from eight independent stations in the Northern California Seismic Network.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S31D4454M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S31D4454M"><span>Dual Megathrust Slip Behaviors of the 2014 Iquique <span class="hlt">Earthquake</span> Sequence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, L.; Huang, H.; Burgmann, R.; Ampuero, J. P.; Strader, A. E.</p> <p>2014-12-01</p> <p>The transition between seismic rupture and aseismic creep is of central interest to better understand the mechanics of subduction processes. A M 8.2 <span class="hlt">earthquake</span> occurred on April 1st, 2014 in the Iquique seismic gap of Northern Chile. This event was preceded by a 2-week-long foreshock sequence including a M 6.7 <span class="hlt">earthquake</span>. Repeating <span class="hlt">earthquakes</span> are found among the foreshock sequence that migrated towards the mainshock area, suggesting a large scale slow-slip event on the megathrust preceding the mainshock. The variations of the <span class="hlt">recurrence</span> time of repeating <span class="hlt">earthquakes</span> highlights the diverse seismic and aseismic slip behaviors on different megathrust segments. The repeaters that were active only before the mainshock recurred more often and were distributed in areas of substantial coseismic slip, while other repeaters occurred both before and after the mainshock in the area complementary to the mainshock rupture. The spatial and temporal distribution of the repeating <span class="hlt">earthquakes</span> illustrate the essential role of propagating aseismic slip in leading up to the mainshock and aftershock activities. Various finite fault models indicate that the coseismic slip generally occurred down-dip from the foreshock activity and the mainshock hypocenter. Source imaging by teleseismic back-projection indicates an initial down-dip propagation stage followed by a rupture-expansion stage. In the first stage, the finite fault models show slow initiation with low amplitude moment <span class="hlt">rate</span> at low frequency (< 0.1 Hz), while back-projection shows a steady initiation at high frequency (> 0.5 Hz). This indicates frequency-dependent manifestations of seismic radiation in the low-stress foreshock region. In the second stage, the high-frequency rupture remains within an area of low gravity anomaly, suggesting possible upper-crustal structures that promote high-frequency generation. Back-projection also shows an episode of reverse rupture propagation which suggests a delayed failure of asperities in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S41C0801S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S41C0801S"><span>The Effect of <span class="hlt">Earthquakes</span> on Episodic Tremor and Slip Events on the Southern Cascadia Subduction Zone</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sainvil, A. K.; Schmidt, D. A.; Nuyen, C.</p> <p>2017-12-01</p> <p>The goal of this study is to explore how slow slip events on the southern Cascadia Subduction Zone respond to nearby, offshore <span class="hlt">earthquakes</span> by examining GPS and tremor data. At intermediate depths on the plate interface ( 40 km), transient fault slip is observed in the form of Episodic Tremor and Slip (ETS) events. These ETS events occur regularly (every 10 months), and have a longer duration than normal <span class="hlt">earthquakes</span>. Researchers have been documenting slow slip events through data obtained by continuously running GPS stations in the Pacific Northwest. Some studies have proposed that pore fluid may play a role in these ETS events by lowering the effective stress on the fault. The interaction of <span class="hlt">earthquakes</span> and ETS can provide constraints on the strength of the fault and the level of stress needed to alter ETS behavior. <span class="hlt">Earthquakes</span> can trigger ETS events, but the connection between these events and <span class="hlt">earthquake</span> activity is less understood. We originally hypothesized that ETS events would be affected by <span class="hlt">earthquakes</span> in southern Cascadia, and could result in a shift in the <span class="hlt">recurrence</span> interval of ETS events. ETS events were cataloged using GPS time series provided by PANGA, in conjunction with tremor positions, in Southern Cascadia for stations YBHB and DDSN from 1997 to 2017. We looked for evidence of change from three offshore <span class="hlt">earthquakes</span> that occurred near the Mendocino Triple Junction with moment magnitudes of 7.2 in 2005, 6.5 in 2010, and 6.8 in 2014. Our results showed that the <span class="hlt">recurrence</span> interval of ETS for stations YBHB and DDSN was not altered by the three <span class="hlt">earthquake</span> events. Future is needed to explore whether this lack of interaction is explained by the non-optimal orientation of the receiver fault for the <span class="hlt">earthquake</span> focal mechanisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T42A..04R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T42A..04R"><span>Slip-accumulation patterns and <span class="hlt">earthquake</span> <span class="hlt">recurrences</span> along the Talas-Fergana Fault - Contributions of high-resolution geomorphic offsets.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rizza, M.; Dubois, C.; Fleury, J.; Abdrakhmatov, K.; Pousse, L.; Baikulov, S.; Vezinet, A.</p> <p>2017-12-01</p> <p>In the western Tien-Shan Range, the largest intracontinental strike-slip fault is the Karatau-Talas Fergana Fault system. This dextral fault system is subdivided into two main segments: the Karatau fault to the north and the Talas-Fergana fault (TFF) to the south. Kinematics and <span class="hlt">rates</span> of deformation for the TFF during the Quaternary period are still debated and are poorly constrained. Only a few paleoseismological investigations are availabe along the TFF (Burtman et al., 1996; Korjenkov et al., 2010) and no systematic quantifications of the dextral displacements along the TFF has been undertaken. As such, the appraisal of the TFF behavior demands new tectonic information. In this study, we present the first detailed analysis of the morphology and the segmentation of the TFF and an offset inventory of morphological markers along the TFF. To discuss temporal and spatial <span class="hlt">recurrence</span> patterns of slip accumulated over multiple seismic events, our study focused on a 60 km-long section of the TFF (Chatkal segment). Using tri-stereo Pleiades satellite images, high-resolution DEMs (1*1 m pixel size) have been generated in order to (i) analyze the fine-scale fault geometry and (ii) thoroughly measure geomorphic offsets. Photogrammetry data obtained from our drone survey on high interest sites, provide higher-resolution DEMs of 0.5 * 0.5 m pixel size.Our remote sensing mapping allows an unprecedented subdivision - into five distinct segments - of the study area. About 215 geomorphic markers have been measured and offsets range from 4.5m to 180 m. More than 80% of these offsets are smaller than 60 m, suggesting landscape reset during glacial maximum. Calculations of Cumulative Offset Probability Density (COPD) for the whole 60 km-long section as well as for each segments support distinct behavior from a segment to another and thus variability in slip-accumulation patterns. Our data argue for uniform slip model behavior along this section of the TFF. Moreover, we excavated a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1692b0024G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1692b0024G"><span>Valuation of Indonesian catastrophic <span class="hlt">earthquake</span> bonds with generalized extreme value (GEV) distribution and Cox-Ingersoll-Ross (CIR) interest <span class="hlt">rate</span> model</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gunardi, Setiawan, Ezra Putranda</p> <p>2015-12-01</p> <p>Indonesia is a country with high risk of <span class="hlt">earthquake</span>, because of its position in the border of earth's tectonic plate. An <span class="hlt">earthquake</span> could raise very high amount of damage, loss, and other economic impacts. So, Indonesia needs a mechanism for transferring the risk of <span class="hlt">earthquake</span> from the government or the (reinsurance) company, as it could collect enough money for implementing the rehabilitation and reconstruction program. One of the mechanisms is by issuing catastrophe bond, `act-of-God bond', or simply CAT bond. A catastrophe bond issued by a special-purpose-vehicle (SPV) company, and then sold to the investor. The revenue from this transaction is joined with the money (premium) from the sponsor company and then invested in other product. If a catastrophe happened before the time-of-maturity, cash flow from the SPV to the investor will discounted or stopped, and the cash flow is paid to the sponsor company to compensate their loss because of this catastrophe event. When we consider the <span class="hlt">earthquake</span> only, the amount of discounted cash flow could determine based on the <span class="hlt">earthquake</span>'s magnitude. A case study with Indonesian <span class="hlt">earthquake</span> magnitude data show that the probability of maximum magnitude can model by generalized extreme value (GEV) distribution. In pricing this catastrophe bond, we assumed stochastic interest <span class="hlt">rate</span> that following the Cox-Ingersoll-Ross (CIR) interest <span class="hlt">rate</span> model. We develop formulas for pricing three types of catastrophe bond, namely zero coupon bonds, `coupon only at risk' bond, and `principal and coupon at risk' bond. Relationship between price of the catastrophe bond and CIR model's parameter, GEV's parameter, percentage of coupon, and discounted cash flow rule then explained via Monte Carlo simulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1813189G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1813189G"><span>Geological evidence for Holocene <span class="hlt">earthquakes</span> and tsunamis along the Nankai-Suruga Trough, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Garrett, Ed; Fujiwara, Osamu; Garrett, Philip; Heyvaert, Vanessa M. A.; Shishikura, Masanobu; Yokoyama, Yusuke; Hubert-Ferrari, Aurélia; Brückner, Helmut; Nakamura, Atsunori; De Batist, Marc</p> <p>2016-04-01</p> <p>The Nankai-Suruga Trough, lying immediately south of Japan's densely populated and highly industrialised southern coastline, generates devastating great <span class="hlt">earthquakes</span> (magnitude > 8). Intense shaking, crustal deformation and tsunami generation accompany these ruptures. Forecasting the hazards associated with future <span class="hlt">earthquakes</span> along this >700 km long fault requires a comprehensive understanding of past fault behaviour. While the region benefits from a long and detailed historical record, palaeoseismology has the potential to provide a longer-term perspective and additional insights. Here, we summarise the current state of knowledge regarding geological evidence for past <span class="hlt">earthquakes</span> and tsunamis, incorporating literature originally published in both Japanese and English. This evidence comes from a wide variety of sources, including uplifted marine terraces and biota, marine and lacustrine turbidites, liquefaction features, subsided marshes and tsunami deposits in coastal lakes and lowlands. We enhance available results with new age modelling approaches. While publications describe proposed evidence from > 70 sites, only a limited number provide compelling, well-dated evidence. The best available records allow us to map the most likely rupture zones of eleven <span class="hlt">earthquakes</span> occurring during the historical period. Our spatiotemporal compilation suggests the AD 1707 <span class="hlt">earthquake</span> ruptured almost the full length of the subduction zone and that <span class="hlt">earthquakes</span> in AD 1361 and 684 were predecessors of similar magnitude. Intervening <span class="hlt">earthquakes</span> were of lesser magnitude, highlighting variability in rupture mode. <span class="hlt">Recurrence</span> intervals for ruptures of the a single seismic segment range from less than 100 to more than 450 years during the historical period. Over longer timescales, palaeoseismic evidence suggests intervals ranging from 100 to 700 years. However, these figures reflect thresholds of evidence creation and preservation as well as genuine <span class="hlt">recurrence</span> intervals. At present, we have</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030235','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030235"><span>12 May 2008 M = 7.9 Wenchuan, China, <span class="hlt">earthquake</span> calculated to increase failure stress and seismicity <span class="hlt">rate</span> on three major fault systems</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Toda, S.; Lin, J.; Meghraoui, M.; Stein, R.S.</p> <p>2008-01-01</p> <p>The Wenchuan <span class="hlt">earthquake</span> on the Longmen Shan fault zone devastated cities of Sichuan, claiming at least 69,000 lives. We calculate that the <span class="hlt">earthquake</span> also brought the Xianshuihe, Kunlun and Min Jiang faults 150-400 km from the mainshock rupture in the eastern Tibetan Plateau 0.2-0.5 bars closer to Coulomb failure. Because some portions of these stressed faults have not ruptured in more than a century, the <span class="hlt">earthquake</span> could trigger or hasten additional M > 7 <span class="hlt">earthquakes</span>, potentially subjecting regions from Kangding to Daofu and Maqin to Rangtag to strong shaking. We use the calculated stress changes and the observed background seismicity to forecast the <span class="hlt">rate</span> and distribution of damaging shocks. The <span class="hlt">earthquake</span> probability in the region is estimated to be 57-71% for M ??? 6 shocks during the next decade, and 8-12% for M ??? 7 shocks. These are up to twice the probabilities for the decade before the Wenchuan <span class="hlt">earthquake</span> struck. Copyright 2008 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/21587720-failure-rates-patterns-recurrence-patients-resected-n1-non-small-cell-lung-cancer','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/21587720-failure-rates-patterns-recurrence-patients-resected-n1-non-small-cell-lung-cancer"><span>Failure <span class="hlt">Rates</span> and Patterns of <span class="hlt">Recurrence</span> in Patients With Resected N1 Non-Small-Cell Lung Cancer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Varlotto, John M., E-mail: jvarlotto@hmc.psu.edu; Medford-Davis, Laura Nyshel; Recht, Abram</p> <p>2011-10-01</p> <p>Purpose: To examine the local and distant <span class="hlt">recurrence</span> <span class="hlt">rates</span> and patterns of failure in patients undergoing potentially curative resection of N1 non-small-cell lung cancer. Methods and Materials: The study included 60 consecutive unirradiated patients treated from 2000 to 2006. Median follow-up was 30 months. Failure <span class="hlt">rates</span> were calculated by the Kaplan-Meier method. A univariate Cox proportional hazard model was used to assess factors associated with <span class="hlt">recurrence</span>. Results: Local and distant failure <span class="hlt">rates</span> (as the first site of failure) at 2, 3, and 5 years were 33%, 33%, and 46%; and 26%, 26%, and 32%, respectively. The most common site ofmore » local failure was in the mediastinum; 12 of 18 local <span class="hlt">recurrences</span> would have been included within proposed postoperative radiotherapy fields. Patients who received chemotherapy were found to be at increased risk of local failure, whereas those who underwent pneumonectomy or who had more positive nodes had significantly increased risks of distant failure. Conclusions: Patients with resected non-small-cell lung cancer who have N1 disease are at substantial risk of local <span class="hlt">recurrence</span> as the first site of relapse, which is greater than the risk of distant failure. The role of postoperative radiotherapy in such patients should be revisited in the era of adjuvant chemotherapy.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29543959','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29543959"><span>Single-Stage Mastoid Obliteration in Cholesteatoma Surgery and <span class="hlt">Recurrent</span> and Residual Disease <span class="hlt">Rates</span>: A Systematic Review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>van der Toom, Hylke F E; van der Schroeff, Marc P; Pauw, Robert J</p> <p>2018-05-01</p> <p>The ideal surgical treatment of cholesteatoma has been subject to discussion for years because both traditional surgical techniques (canal wall down [CWD] and canal wall up [CWU] tympanoplasty) have their own advantages and disadvantages. A more recently propagated surgical approach, to combine the CWD or CWU tympanoplasty technique with obliteration of the mastoid and epitympanum, is showing promising results. To systematically review the literature on <span class="hlt">recurrent</span> and residual cholesteatoma <span class="hlt">rates</span> after single-stage CWU and CWD tympanoplasty with mastoid obliteration. A systematic search of literature was performed to identify relevant publications in multiple electronic databases. The initial search was conducted in December 2016 and was updated in July 2017. Each study was reviewed by 2 independent reviewers on predetermined eligibility criteria. The methodological quality was determined using the methodological index for nonrandomized studies (MINORS) scale, and the relevance to the current topic was determined using a 4-criterion checklist. The searches identified a total of 336 potentially relevant publications; 190 articles were excluded based on title and abstract. The full-text articles of the remaining 146 citations were assessed for eligibility, resulting in 22 articles. After assessing these remaining articles for methodological quality and relevance to the current topic, another 8 studies were excluded, and a total of 13 studies (1534 patients) were included. Of the 1534 patients who underwent CWD or CWU tympanoplasty with mastoid obliteration, the <span class="hlt">rate</span> of <span class="hlt">recurrent</span> disease was 4.6%, and the <span class="hlt">rate</span> of residual disease was 5.4%. In CWU tympanoplasty with mastoid obliteration, these <span class="hlt">rates</span> were 0.28% and 4.2%, respectively and in CWD tympanoplasty with mastoid obliteration, 5.9% and 5.8%, respectively. We show the <span class="hlt">recurrent</span> and residual disease <span class="hlt">rates</span> after either CWU or CWD tympanoplasty with mastoid obliteration to be qualitatively similar to, if not better</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985JGR....90.3589N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985JGR....90.3589N"><span>Seismic potential for large and great interplate <span class="hlt">earthquakes</span> along the Chilean and Southern Peruvian Margins of South America: A quantitative reappraisal</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nishenko, Stuart P.</p> <p>1985-04-01</p> <p>The seismic potential of the Chilean and southern Peruvian margins of South America is reevaluated to delineate those areas or segments of the margin that may be expected to experience large or great interplate <span class="hlt">earthquakes</span> within the next 20 years (1984-2004). Long-term estimates of seismic potential (or the conditional probability of <span class="hlt">recurrence</span> within a specified period of time) are based on (1) statistical analysis of historic repeat time data using Weibull distributions and (2) deterministic estimates of <span class="hlt">recurrence</span> times based on the time-predictable model of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>. Both methods emphasize the periodic nature of large and great <span class="hlt">earthquake</span> <span class="hlt">recurrence</span>, and are compared with estimates of probability based on the assumption of Poisson-type behavior. The estimates of seismic potential presented in this study are long-term forecasts only, as the temporal resolution (or standard deviation) of both methods is taken to range from ±15% to ±25% of the average or estimated repeat time. At present, the Valparaiso region of central Chile (32°-35°S) has a high potential or probability of <span class="hlt">recurrence</span> in the next 20 years. Coseismic uplift data associated with previous shocks in 1822 and 1906 suggest that this area may have already started to rerupture in 1971-1973. Average repeat times also suggest this area is due for a great shock within the next 20 years. Flanking segments of the Chilean margin, Coquimbo-Illapel (30°-32°S) and Talca-Concepcion (35°-38°S), presently have poorly constrained but possibly quite high potentials for a series of large or great shocks within the next 20 years. In contrast, the rupture zone of the great 1960 <span class="hlt">earthquake</span> (37°-46°S) has the lowest potential along the margin and is not expected to rerupture in a great <span class="hlt">earthquake</span> within the next 100 years. In the north, the seismic potentials of the Mollendo-Arica (17°-18°S) and Arica-Antofagasta (18°-24°S) segments (which last ruptured during great <span class="hlt">earthquakes</span> in 1868 and 1877</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1811006N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1811006N"><span>Spatial Distribution of the Coefficient of Variation and Bayesian Forecast for the Paleo-<span class="hlt">Earthquakes</span> in Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nomura, Shunichi; Ogata, Yosihiko</p> <p>2016-04-01</p> <p>We propose a Bayesian method of probability forecasting for <span class="hlt">recurrent</span> <span class="hlt">earthquakes</span> of inland active faults in Japan. Renewal processes with the Brownian Passage Time (BPT) distribution are applied for over a half of active faults in Japan by the Headquarters for <span class="hlt">Earthquake</span> Research Promotion (HERP) of Japan. Long-term forecast with the BPT distribution needs two parameters; the mean and coefficient of variation (COV) for <span class="hlt">recurrence</span> intervals. The HERP applies a common COV parameter for all of these faults because most of them have very few specified paleoseismic events, which is not enough to estimate reliable COV values for respective faults. However, different COV estimates are proposed for the same paleoseismic catalog by some related works. It can make critical difference in forecast to apply different COV estimates and so COV should be carefully selected for individual faults. <span class="hlt">Recurrence</span> intervals on a fault are, on the average, determined by the long-term slip <span class="hlt">rate</span> caused by the tectonic motion but fluctuated by nearby seismicities which influence surrounding stress field. The COVs of <span class="hlt">recurrence</span> intervals depend on such stress perturbation and so have spatial trends due to the heterogeneity of tectonic motion and seismicity. Thus we introduce a spatial structure on its COV parameter by Bayesian modeling with a Gaussian process prior. The COVs on active faults are correlated and take similar values for closely located faults. It is found that the spatial trends in the estimated COV values coincide with the density of active faults in Japan. We also show Bayesian forecasts by the proposed model using Markov chain Monte Carlo method. Our forecasts are different from HERP's forecast especially on the active faults where HERP's forecasts are very high or low.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.U33A..04A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.U33A..04A"><span>Salient Features of the 2015 Gorkha, Nepal <span class="hlt">Earthquake</span> in Relation to <span class="hlt">Earthquake</span> Cycle and Dynamic Rupture Models</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ampuero, J. P.; Meng, L.; Hough, S. E.; Martin, S. S.; Asimaki, D.</p> <p>2015-12-01</p> <p>Two salient features of the 2015 Gorkha, Nepal, <span class="hlt">earthquake</span> provide new opportunities to evaluate models of <span class="hlt">earthquake</span> cycle and dynamic rupture. The Gorkha <span class="hlt">earthquake</span> broke only partially across the seismogenic depth of the Main Himalayan Thrust: its slip was confined in a narrow depth range near the bottom of the locked zone. As indicated by the belt of background seismicity and decades of geodetic monitoring, this is an area of stress concentration induced by deep fault creep. Previous conceptual models attribute such intermediate-size events to rheological segmentation along-dip, including a fault segment with intermediate rheology in between the stable and unstable slip segments. We will present results from <span class="hlt">earthquake</span> cycle models that, in contrast, highlight the role of stress loading concentration, rather than frictional segmentation. These models produce "super-cycles" comprising <span class="hlt">recurrent</span> characteristic events interspersed by deep, smaller non-characteristic events of overall increasing magnitude. Because the non-characteristic events are an intrinsic component of the <span class="hlt">earthquake</span> super-cycle, the notion of Coulomb triggering or time-advance of the "big one" is ill-defined. The high-frequency (HF) ground motions produced in Kathmandu by the Gorkha <span class="hlt">earthquake</span> were weaker than expected for such a magnitude and such close distance to the rupture, as attested by strong motion recordings and by macroseismic data. Static slip reached close to Kathmandu but had a long rise time, consistent with control by the along-dip extent of the rupture. Moreover, the HF (1 Hz) radiation sources, imaged by teleseismic back-projection of multiple dense arrays calibrated by aftershock data, was deep and far from Kathmandu. We argue that HF rupture imaging provided a better predictor of shaking intensity than finite source inversion. The deep location of HF radiation can be attributed to rupture over heterogeneous initial stresses left by the background seismic activity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JSAES..33..102C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JSAES..33..102C"><span>Amending and complicating Chile’s seismic catalog with the Santiago <span class="hlt">earthquake</span> of 7 August 1580</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cisternas, Marco; Torrejón, Fernando; Gorigoitia, Nicolás</p> <p>2012-02-01</p> <p>Historical <span class="hlt">earthquakes</span> of Chile's metropolitan region include a previously uncatalogued <span class="hlt">earthquake</span> that occurred on 7 August 1580 in the Julian calendar. We found an authoritative account of this <span class="hlt">earthquake</span> in a letter written four days later in Santiago and now archived in Spain. The letter tells of a destructive <span class="hlt">earthquake</span> that struck Santiago and its environs. In its reported effects it surpassed the one in the same city in 1575, until now presumed to be the only <span class="hlt">earthquake</span> in the first century of central Chile's written history. It is not yet possible to identify the source of the 1580 <span class="hlt">earthquake</span> but viable candidates include both the plate boundary and Andean faults at shallows depths around Santiago. By occurring just five years after another large <span class="hlt">earthquake</span>, the 1580 <span class="hlt">earthquake</span> casts doubt on the completeness of the region's historical <span class="hlt">earthquake</span> catalog and the periodicity of its large <span class="hlt">earthquakes</span>. That catalog, based on eyewitness accounts compiled mainly by Alexander Perrey and Fernand Montessus de Ballore, tells of large Chile's metropolitan region <span class="hlt">earthquakes</span> in 1575, 1647, 1730, 1822, 1906 and 1985. The addition of a large <span class="hlt">earthquake</span> in 1580 implies greater variability in <span class="hlt">recurrence</span> intervals and may also mean greater variety in <span class="hlt">earthquake</span> sources.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18439133','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18439133"><span>Exact solutions for <span class="hlt">rate</span> and synchrony in <span class="hlt">recurrent</span> networks of coincidence detectors.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mikula, Shawn; Niebur, Ernst</p> <p>2008-11-01</p> <p>We provide analytical solutions for mean firing <span class="hlt">rates</span> and cross-correlations of coincidence detector neurons in <span class="hlt">recurrent</span> networks with excitatory or inhibitory connectivity, with <span class="hlt">rate</span>-modulated steady-state spiking inputs. We use discrete-time finite-state Markov chains to represent network state transition probabilities, which are subsequently used to derive exact analytical solutions for mean firing <span class="hlt">rates</span> and cross-correlations. As illustrated in several examples, the method can be used for modeling cortical microcircuits and clarifying single-neuron and population coding mechanisms. We also demonstrate that increasing firing <span class="hlt">rates</span> do not necessarily translate into increasing cross-correlations, though our results do support the contention that firing <span class="hlt">rates</span> and cross-correlations are likely to be coupled. Our analytical solutions underscore the complexity of the relationship between firing <span class="hlt">rates</span> and cross-correlations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2722920','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2722920"><span>Exact Solutions for <span class="hlt">Rate</span> and Synchrony in <span class="hlt">Recurrent</span> Networks of Coincidence Detectors</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mikula, Shawn; Niebur, Ernst</p> <p>2009-01-01</p> <p>We provide analytical solutions for mean firing <span class="hlt">rates</span> and cross-correlations of coincidence detector neurons in <span class="hlt">recurrent</span> networks with excitatory or inhibitory connectivity with <span class="hlt">rate</span>-modulated steady-state spiking inputs. We use discrete-time finite-state Markov chains to represent network state transition probabilities, which are subsequently used to derive exact analytical solutions for mean firing <span class="hlt">rates</span> and cross-correlations. As illustrated in several examples, the method can be used for modeling cortical microcircuits and clarifying single-neuron and population coding mechanisms. We also demonstrate that increasing firing <span class="hlt">rates</span> do not necessarily translate into increasing cross-correlations, though our results do support the contention that firing <span class="hlt">rates</span> and cross-correlations are likely to be coupled. Our analytical solutions underscore the complexity of the relationship between firing <span class="hlt">rates</span> and cross-correlations. PMID:18439133</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1162/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1162/"><span><span class="hlt">Earthquake</span> <span class="hlt">Rate</span> Model 2.2 of the 2007 Working Group for California <span class="hlt">Earthquake</span> Probabilities, Appendix D: Magnitude-Area Relationships</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stein, Ross S.</p> <p>2007-01-01</p> <p>Summary To estimate the down-dip coseismic fault dimension, W, the Executive Committee has chosen the Nazareth and Hauksson (2004) method, which uses the 99% depth of background seismicity to assign W. For the predicted <span class="hlt">earthquake</span> magnitude-fault area scaling used to estimate the maximum magnitude of an <span class="hlt">earthquake</span> rupture from a fault's length, L, and W, the Committee has assigned equal weight to the Ellsworth B (Working Group on California <span class="hlt">Earthquake</span> Probabilities, 2003) and Hanks and Bakun (2002) (as updated in 2007) equations. The former uses a single relation; the latter uses a bilinear relation which changes slope at M=6.65 (A=537 km2).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70141609','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70141609"><span>The 2011 Mineral, Virginia, <span class="hlt">earthquake</span> and its significance for seismic hazards in eastern North America: overview and synthesis</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Horton, J. Wright; Chapman, Martin C.; Green, Russell A.</p> <p>2015-01-01</p> <p>The <span class="hlt">earthquake</span> and aftershocks occurred in crystalline rocks within Paleozoic thrust sheets of the Chopawamsic terrane. The main shock and majority of aftershocks delineated the newly named Quail fault zone in the subsurface, and shallow aftershocks defined outlying faults. The <span class="hlt">earthquake</span> induced minor liquefaction sand boils, but notably there was no evidence of a surface fault rupture. <span class="hlt">Recurrence</span> intervals, and evidence for larger <span class="hlt">earthquakes</span> in the Quaternary in this area, remain important unknowns. This event, along with similar events during historical time, is a reminder that <span class="hlt">earthquakes</span> of similar or larger magnitude pose a real hazard in eastern North America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70019406','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70019406"><span>An <span class="hlt">earthquake</span> history derived from stratigraphic and microfossil evidence of relative sea-level change at Coos Bay, southern coastal Oregon</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, A.R.; Jennings, A.E.; Kashima, K.</p> <p>1996-01-01</p> <p>Much of the uncertainty in determining the number and magnitude of past great <span class="hlt">earthquakes</span> in the Cascadia subduction zone of western North America stems from difficulties in using estuarine stratigraphy to infer the size and <span class="hlt">rate</span> of late Holocene relative sea-level changes. A sequence of interbedded peaty and muddy intertidal sediment beneath a small, protected tidal marsh in a narrow inlet of Coos Bay, Oregon, records ten rapid to instantaneous rises in relative sea level. Each rise is marked by a contact that records an upward transition from peaty to muddy sediment. But only two contacts, dating from about 1700 and 2300 yr ago, show the site-wide extent and abrupt changes in lithology and foraminiferal and diatom assemblages that can be used to infer at least half a meter of sudden coseismic subsidence. Although the characteristics of a third, gradual contact do not differ from those of some contacts produced by nonseismic processes, regional correlation with other similar sequences and high-precision 14C dating suggest that the third contact records a great plate-boundary <span class="hlt">earthquake</span> about 300 yr ago. A fourth contact formed too slowly to have been caused by coseismic subsidence. Because lithologic and microfossil data are not sufficient to distinguish a coseismic from a nonseismic origin for the other six peatmud contacts, we cannot determine <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals at this site. Similar uncertainties in great <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> and magnitude prevail at similar sites elsewhere in the Cascadia subduction zone, except those with sequences showing changes in fossils indicative of > 1 m of sudden subsidence, sand sheets deposited by tsunamis, or liquefaction features.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22184228','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22184228"><span>Global risk of big <span class="hlt">earthquakes</span> has not recently increased.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shearer, Peter M; Stark, Philip B</p> <p>2012-01-17</p> <p>The recent elevated <span class="hlt">rate</span> of large <span class="hlt">earthquakes</span> has fueled concern that the underlying global <span class="hlt">rate</span> of <span class="hlt">earthquake</span> activity has increased, which would have important implications for assessments of seismic hazard and our understanding of how faults interact. We examine the timing of large (magnitude M≥7) <span class="hlt">earthquakes</span> from 1900 to the present, after removing local clustering related to aftershocks. The global <span class="hlt">rate</span> of M≥8 <span class="hlt">earthquakes</span> has been at a record high roughly since 2004, but <span class="hlt">rates</span> have been almost as high before, and the <span class="hlt">rate</span> of smaller <span class="hlt">earthquakes</span> is close to its historical average. Some features of the global catalog are improbable in retrospect, but so are some features of most random sequences--if the features are selected after looking at the data. For a variety of magnitude cutoffs and three statistical tests, the global catalog, with local clusters removed, is not distinguishable from a homogeneous Poisson process. Moreover, no plausible physical mechanism predicts real changes in the underlying global <span class="hlt">rate</span> of large events. Together these facts suggest that the global risk of large <span class="hlt">earthquakes</span> is no higher today than it has been in the past.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3271898','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3271898"><span>Global risk of big <span class="hlt">earthquakes</span> has not recently increased</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Shearer, Peter M.; Stark, Philip B.</p> <p>2012-01-01</p> <p>The recent elevated <span class="hlt">rate</span> of large <span class="hlt">earthquakes</span> has fueled concern that the underlying global <span class="hlt">rate</span> of <span class="hlt">earthquake</span> activity has increased, which would have important implications for assessments of seismic hazard and our understanding of how faults interact. We examine the timing of large (magnitude M≥7) <span class="hlt">earthquakes</span> from 1900 to the present, after removing local clustering related to aftershocks. The global <span class="hlt">rate</span> of M≥8 <span class="hlt">earthquakes</span> has been at a record high roughly since 2004, but <span class="hlt">rates</span> have been almost as high before, and the <span class="hlt">rate</span> of smaller <span class="hlt">earthquakes</span> is close to its historical average. Some features of the global catalog are improbable in retrospect, but so are some features of most random sequences—if the features are selected after looking at the data. For a variety of magnitude cutoffs and three statistical tests, the global catalog, with local clusters removed, is not distinguishable from a homogeneous Poisson process. Moreover, no plausible physical mechanism predicts real changes in the underlying global <span class="hlt">rate</span> of large events. Together these facts suggest that the global risk of large <span class="hlt">earthquakes</span> is no higher today than it has been in the past. PMID:22184228</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.1569J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.1569J"><span>Identified EM <span class="hlt">Earthquake</span> Precursors</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jones, Kenneth, II; Saxton, Patrick</p> <p>2014-05-01</p> <p> <span class="hlt">recurrence</span>, duration, and frequency response. At the Southern California field sites, one loop antenna was positioned for omni-directional reception and also detected a strong First Schumann Resonance; however, additional Schumann Resonances were absent. At the Timpson, TX field sites, loop antennae were positioned for directional reception, due to <span class="hlt">earthquake</span>-induced, hydraulic fracturing activity currently conducted by the oil and gas industry. Two strong signals, one moderately strong signal, and approximately 6-8 weaker signals were detected in the immediate vicinity. The three stronger signals were mapped by a biangulation technique, followed by a triangulation technique for confirmation. This was the first antenna mapping technique ever performed for determining possible <span class="hlt">earthquake</span> epicenters. Six and a half months later, Timpson experienced two M4 (M4.1 and M4.3) <span class="hlt">earthquakes</span> on September 2, 2013 followed by a M2.4 <span class="hlt">earthquake</span> three days later, all occurring at a depth of five kilometers. The Timpson <span class="hlt">earthquake</span> activity now has a cyclical <span class="hlt">rate</span> and a forecast was given to the proper authorities. As a result, the Southern California and Timpson, TX field results led to an improved design and construction of a third prototype antenna. With a loop antenna array, a viable communication system, and continuous monitoring, a full fracture cycle can be established and observed in real-time. In addition, field data could be reviewed quickly for assessment and lead to a much more improved <span class="hlt">earthquake</span> forecasting capability. The EM precursors determined by this method appear to surpass all prior precursor claims, and the general public will finally receive long overdue forecasting.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28423231','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28423231"><span>Direct-acting antiviral therapy decreases hepatocellular carcinoma <span class="hlt">recurrence</span> <span class="hlt">rate</span> in cirrhotic patients with chronic hepatitis C.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Virlogeux, Victor; Pradat, Pierre; Hartig-Lavie, Kerstin; Bailly, François; Maynard, Marianne; Ouziel, Guillaume; Poinsot, Domitille; Lebossé, Fanny; Ecochard, Marie; Radenne, Sylvie; Benmakhlouf, Samir; Koffi, Joseph; Lack, Philippe; Scholtes, Caroline; Uhres, Anne-Claire; Ducerf, Christian; Mabrut, Jean-Yves; Rode, Agnès; Levrero, Massimo; Combet, Christophe; Merle, Philippe; Zoulim, Fabien</p> <p>2017-08-01</p> <p>Arrival of direct-acting antiviral agents against hepatitis C virus with high-sustained virological response <span class="hlt">rates</span> and very few side effects has drastically changed the management of hepatitis C virus infection. The impact of direct-acting antiviral exposure on hepatocellular carcinoma <span class="hlt">recurrence</span> after a first remission in patients with advanced fibrosis remains to be clarified. 68 consecutive hepatitis C virus patients with a first hepatocellular carcinoma diagnosis and under remission, subsequently treated or not with a direct-acting antiviral combination, were included. Clinical, biological and virological data were collected at first hepatocellular carcinoma diagnosis, at remission and during the surveillance period. All patients were cirrhotic. Median age was 62 years and 76% of patients were male. Twenty-three patients (34%) were treated with direct-acting antivirals and 96% of them achieved sustained virological response. Median time between hepatocellular carcinoma remission and direct-acting antivirals initiation was 7.2 months (IQR: 3.6-13.5; range: 0.3-71.4) and median time between direct-acting antivirals start and hepatocellular carcinoma <span class="hlt">recurrence</span> was 13.0 months (IQR: 9.2-19.6; range: 3.0-24.7). <span class="hlt">Recurrence</span> <span class="hlt">rate</span> was 1.7/100 person-months among treated patients vs 4.2/100 person-months among untreated patients (P=.008). In multivariate survival analysis, the hazard ratio for hepatocellular carcinoma <span class="hlt">recurrence</span> after direct-acting antivirals exposure was 0.24 (95% confidence interval: 0.10-0.55; P<.001). Hepatocellular carcinoma <span class="hlt">recurrence</span> <span class="hlt">rate</span> was significantly lower among patients treated with direct-acting antivirals compared with untreated patients. Given the potential impact of our observation, large-scale prospective cohort studies are needed to confirm these results. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhyD..171..249B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhyD..171..249B"><span>Assessing nonlinear structures in real exchange <span class="hlt">rates</span> using <span class="hlt">recurrence</span> plot strategies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Belaire-Franch, Jorge; Contreras, Dulce; Tordera-Lledó, Lorena</p> <p>2002-11-01</p> <p>Purchasing power parity (PPP) is an important theory at the basis of a large number of economic models. However, the implication derived from the theory that real exchange <span class="hlt">rates</span> must follow stationary processes is not conclusively supported by empirical studies. In a recent paper, Serletis and Gogas [Appl. Finance Econ. 10 (2000) 615] show evidence of deterministic chaos in several OECD exchange <span class="hlt">rates</span>. As a consequence, PPP rejections could be spurious. In this work, we follow a two-stage testing procedure to test for nonlinearities and chaos in real exchange <span class="hlt">rates</span>, using a new set of techniques designed by Webber and Zbilut [J. Appl. Physiol. 76 (1994) 965], called <span class="hlt">recurrence</span> quantification analysis (RQA). Our conclusions differ slightly from Serletis and Gogas [Appl. Finance Econ. 10 (2000) 615], but they are also supportive of chaos for some exchange <span class="hlt">rates</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/30080','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/30080"><span>Relationship of host <span class="hlt">recurrence</span> in fungi to <span class="hlt">rates</span> of tropical leaf decomposition</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Mirna E. Santanaa; JeanD. Lodgeb; Patricia Lebowc</p> <p>2004-01-01</p> <p>Here we explore the significance of fungal diversity on ecosystem processes by testing whether microfungal ‘preferences’ for (i.e., host <span class="hlt">recurrence</span>) different tropical leaf species increases the <span class="hlt">rate</span> of decomposition. We used pairwise combinations of girradiated litter of five tree species with cultures of two dominant microfungi derived from each plant in a microcosm...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.fs.usda.gov/treesearch/pubs/27114','TREESEARCH'); return false;" href="https://www.fs.usda.gov/treesearch/pubs/27114"><span>Relationship of host <span class="hlt">recurrence</span> in fungi to <span class="hlt">rates</span> of tropical leaf decomposition</span></a></p> <p><a target="_blank" href="http://www.fs.usda.gov/treesearch/">Treesearch</a></p> <p>Mirna E. Santana; D. Jean Lodge; Patricia Lebow</p> <p>2005-01-01</p> <p>Here we explore the significance of fungal diversity on ecosystem processes by testing whether microfungal ‘preferences’ for (i.e., host <span class="hlt">recurrence</span>) different tropical leaf species increases the <span class="hlt">rate</span> of decomposition. We used pairwise combinations of [gamma]-irradiated litter of five tree species with cultures of two dominant microfungi derived from each plant in a...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S31G..01K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S31G..01K"><span>Testing hypotheses of <span class="hlt">earthquake</span> occurrence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kagan, Y. Y.; Jackson, D. D.; Schorlemmer, D.; Gerstenberger, M.</p> <p>2003-12-01</p> <p>We present a relatively straightforward likelihood method for testing those <span class="hlt">earthquake</span> hypotheses that can be stated as vectors of <span class="hlt">earthquake</span> <span class="hlt">rate</span> density in defined bins of area, magnitude, and time. We illustrate the method as it will be applied to the Regional <span class="hlt">Earthquake</span> Likelihood Models (RELM) project of the Southern California <span class="hlt">Earthquake</span> Center (SCEC). Several <span class="hlt">earthquake</span> forecast models are being developed as part of this project, and additional contributed forecasts are welcome. Various models are based on fault geometry and slip <span class="hlt">rates</span>, seismicity, geodetic strain, and stress interactions. We would test models in pairs, requiring that both forecasts in a pair be defined over the same set of bins. Thus we offer a standard "menu" of bins and ground rules to encourage standardization. One menu category includes five-year forecasts of magnitude 5.0 and larger. Forecasts would be in the form of a vector of yearly <span class="hlt">earthquake</span> <span class="hlt">rates</span> on a 0.05 degree grid at the beginning of the test. Focal mechanism forecasts, when available, would be also be archived and used in the tests. The five-year forecast category may be appropriate for testing hypotheses of stress shadows from large <span class="hlt">earthquakes</span>. Interim progress will be evaluated yearly, but final conclusions would be made on the basis of cumulative five-year performance. The second category includes forecasts of <span class="hlt">earthquakes</span> above magnitude 4.0 on a 0.05 degree grid, evaluated and renewed daily. Final evaluation would be based on cumulative performance over five years. Other types of forecasts with different magnitude, space, and time sampling are welcome and will be tested against other models with shared characteristics. All <span class="hlt">earthquakes</span> would be counted, and no attempt made to separate foreshocks, main shocks, and aftershocks. <span class="hlt">Earthquakes</span> would be considered as point sources located at the hypocenter. For each pair of forecasts, we plan to compute alpha, the probability that the first would be wrongly rejected in favor of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19039163','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19039163"><span>The effect of orthostasis on <span class="hlt">recurrence</span> quantification analysis of heart <span class="hlt">rate</span> and blood pressure dynamics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Javorka, M; Turianikova, Z; Tonhajzerova, I; Javorka, K; Baumert, M</p> <p>2009-01-01</p> <p>The purpose of this paper is to investigate the effect of orthostatic challenge on <span class="hlt">recurrence</span> plot based complexity measures of heart <span class="hlt">rate</span> and blood pressure variability (HRV and BPV). HRV and BPV complexities were assessed in 28 healthy subjects over 15 min in the supine and standing positions. The complexity of HRV and BPV was assessed based on <span class="hlt">recurrence</span> quantification analysis. HRV complexity was reduced along with the HRV magnitude after changing from the supine to the standing position. In contrast, the BPV magnitude increased and BPV complexity decreased upon standing. <span class="hlt">Recurrence</span> quantification analysis (RQA) of HRV and BPV is sensitive to orthostatic challenge and might therefore be suited to assess changes in autonomic neural outflow to the cardiovascular system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70019043','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70019043"><span>The 1992 M=7 Cape Mendocino, California, <span class="hlt">earthquake</span>: Coseismic deformation at the south end of the Cascadia megathrust</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Murray, M.H.; Marshall, G.A.; Lisowski, M.; Stein, R.S.</p> <p>1996-01-01</p> <p>We invert geodetic measurements of coseismic surface displacements to determine a dislocation model for the April 25, 1992, M=7 Cape Mendocino, California, <span class="hlt">earthquake</span>. The orientation of the model slip vector, which nearly parallels North America-Juan de Fuca relative plate convergence, and the location and orientation of the model fault relative to the offshore Cascadia megathrust, suggest that the 1992 Cape Mendocino <span class="hlt">earthquake</span> is the first well-recorded event to relieve strain associated with the Cascadia subduction zone. We use data from three geodetic techniques: (1) the horizontal and vertical displacements of 13 monuments surveyed with the Global Positioning System, corrected for observed horizontal interseismic strain accumulation, (2) 88 section-elevation differences between leveling monuments, and (3) the uplift of 12 coastal sites observed from the die-off of intertidal marine organisms. Maximum observed displacements are 0.4 m of horizontal movement and 1.5 m of uplift along the coast. We use Monte Carlo techniques to estimate an optimal uniform slip rectangular fault geometry and its uncertainties. The optimal model using all the data resolves 4.9 m of slip on a 14 by 15 km fault that dips 28?? SE. The fault extends from 1.5 to 8.7 km in depth and the main-shock hypocenter is close to the downdip projection of the fault. The shallowly dipping fault plane is consistent with the observed aftershock locations, and the estimated geodetic moment is 3.1??1019 N m, 70% of the seismic moment. Other models that exclude leveling data collected in 1935 and 1942 are more consistent with seismological estimates of the fault geometry. If the <span class="hlt">earthquake</span> is characteristic for this segment, the estimated horizontal slip vector compared with plate convergence <span class="hlt">rates</span> suggests a <span class="hlt">recurrence</span> interval of 140 years, with a 95% confidence range of 100-670 years. The coseismic uplift occurred in a region that also has high Quaternary uplift <span class="hlt">rates</span> determined from marine terrace</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.211..335K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.211..335K"><span><span class="hlt">Earthquake</span> number forecasts testing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kagan, Yan Y.</p> <p>2017-10-01</p> <p>We study the distributions of <span class="hlt">earthquake</span> numbers in two global <span class="hlt">earthquake</span> catalogues: Global Centroid-Moment Tensor and Preliminary Determinations of Epicenters. The properties of these distributions are especially required to develop the number test for our forecasts of future seismic activity <span class="hlt">rate</span>, tested by the Collaboratory for Study of <span class="hlt">Earthquake</span> Predictability (CSEP). A common assumption, as used in the CSEP tests, is that the numbers are described by the Poisson distribution. It is clear, however, that the Poisson assumption for the <span class="hlt">earthquake</span> number distribution is incorrect, especially for the catalogues with a lower magnitude threshold. In contrast to the one-parameter Poisson distribution so widely used to describe <span class="hlt">earthquake</span> occurrences, the negative-binomial distribution (NBD) has two parameters. The second parameter can be used to characterize the clustering or overdispersion of a process. We also introduce and study a more complex three-parameter beta negative-binomial distribution. We investigate the dependence of parameters for both Poisson and NBD distributions on the catalogue magnitude threshold and on temporal subdivision of catalogue duration. First, we study whether the Poisson law can be statistically rejected for various catalogue subdivisions. We find that for most cases of interest, the Poisson distribution can be shown to be rejected statistically at a high significance level in favour of the NBD. Thereafter, we investigate whether these distributions fit the observed distributions of seismicity. For this purpose, we study upper statistical moments of <span class="hlt">earthquake</span> numbers (skewness and kurtosis) and compare them to the theoretical values for both distributions. Empirical values for the skewness and the kurtosis increase for the smaller magnitude threshold and increase with even greater intensity for small temporal subdivision of catalogues. The Poisson distribution for large <span class="hlt">rate</span> values approaches the Gaussian law, therefore its skewness</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70028819','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70028819"><span>The 1923 Kanto <span class="hlt">earthquake</span> reevaluated using a newly augmented geodetic data set</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nyst, M.; Nishimura, T.; Pollitz, F.F.; Thatcher, W.</p> <p>2006-01-01</p> <p>This study revisits the mechanism of the 1923 Ms = 7.9 Kanto <span class="hlt">earthquake</span> in Japan. We derive a new source model and use it to assess quantitative and qualitative aspects of the accommodation of plate motion in the Kanto region. We use a new geodetic data set that consists of displacements from leveling and angle changes from triangulation measurements obtained in surveys between 1883 and 1927. Two unique aspects of our analysis are the inclusion of a large number of second-order triangulation measurements and the application of a correction to remove interseismic deformation. The geometry of the fault planes is adopted from a recent seismic reflection study of the Kanto region. We evaluate the minimum complexity necessary in the model to fit the data optimally. Our final uniform-slip elastic dislocation model consists of two adjacent ???20?? dipping low-angle planes accommodating reverse dextral slip of 6.0 in on the larger, eastern plane and 9.5 m on the smaller, western plane with azimuths of 163?? and 121??, respectively. The <span class="hlt">earthquake</span> was located in the Sagami trough, where the Philippine Sea plate subducts under Honshu. Compared to the highly oblique angle of plate convergence, the coseismic slip on the large fault plane has a more orthogonal orientation to the strike of the plate boundary, suggesting that slip partitioning plays a role in accommodation of plate motion. What other structure is involved in the partitioning is unclear. Uplift records of marine coastal terraces in Sagami Bay document 7500 years of <span class="hlt">earthquake</span> activity and predict average <span class="hlt">recurrence</span> intervals of 400 years for events with vertical displacement profiles similar to those of the 1923 <span class="hlt">earthquake</span>. This means that the average slip deficit per <span class="hlt">recurrence</span> interval is ???50% of the relative plate convergence. These findings of plate motion partitioning and slip deficit lead us to suggest that instead of a simple <span class="hlt">recurrence</span> model with characteristic <span class="hlt">earthquakes</span>, additional mechanisms are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.1339B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.1339B"><span>Volcanic Eruption Forecasts From Accelerating <span class="hlt">Rates</span> of Drumbeat Long-Period <span class="hlt">Earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bell, Andrew F.; Naylor, Mark; Hernandez, Stephen; Main, Ian G.; Gaunt, H. Elizabeth; Mothes, Patricia; Ruiz, Mario</p> <p>2018-02-01</p> <p>Accelerating <span class="hlt">rates</span> of quasiperiodic "drumbeat" long-period <span class="hlt">earthquakes</span> (LPs) are commonly reported before eruptions at andesite and dacite volcanoes, and promise insights into the nature of fundamental preeruptive processes and improved eruption forecasts. Here we apply a new Bayesian Markov chain Monte Carlo gamma point process methodology to investigate an exceptionally well-developed sequence of drumbeat LPs preceding a recent large vulcanian explosion at Tungurahua volcano, Ecuador. For more than 24 hr, LP <span class="hlt">rates</span> increased according to the inverse power law trend predicted by material failure theory, and with a retrospectively forecast failure time that agrees with the eruption onset within error. LPs resulted from repeated activation of a single characteristic source driven by accelerating loading, rather than a distributed failure process, showing that similar precursory trends can emerge from quite different underlying physics. Nevertheless, such sequences have clear potential for improving forecasts of eruptions at Tungurahua and analogous volcanoes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRB..122.4584J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRB..122.4584J"><span>Sediment gravity flows triggered by remotely generated <span class="hlt">earthquake</span> waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Johnson, H. Paul; Gomberg, Joan S.; Hautala, Susan L.; Salmi, Marie S.</p> <p>2017-06-01</p> <p>Recent great <span class="hlt">earthquakes</span> and tsunamis around the world have heightened awareness of the inevitability of similar events occurring within the Cascadia Subduction Zone of the Pacific Northwest. We analyzed seafloor temperature, pressure, and seismic signals, and video stills of sediment-enveloped instruments recorded during the 2011-2015 Cascadia Initiative experiment, and seafloor morphology. Our results led us to suggest that thick accretionary prism sediments amplified and extended seismic wave durations from the 11 April 2012 Mw8.6 Indian Ocean <span class="hlt">earthquake</span>, located more than 13,500 km away. These waves triggered a sequence of small slope failures on the Cascadia margin that led to sediment gravity flows culminating in turbidity currents. Previous studies have related the triggering of sediment-laden gravity flows and turbidite deposition to local <span class="hlt">earthquakes</span>, but this is the first study in which the originating seismic event is extremely distant (> 10,000 km). The possibility of remotely triggered slope failures that generate sediment-laden gravity flows should be considered in inferences of <span class="hlt">recurrence</span> intervals of past great Cascadia <span class="hlt">earthquakes</span> from turbidite sequences. Future similar studies may provide new understanding of submarine slope failures and turbidity currents and the hazards they pose to seafloor infrastructure and tsunami generation in regions both with and without local <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189210','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189210"><span>Sediment gravity flows triggered by remotely generated <span class="hlt">earthquake</span> waves</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Johnson, H. Paul; Gomberg, Joan S.; Hautala, Susan; Salmi, Marie</p> <p>2017-01-01</p> <p>Recent great <span class="hlt">earthquakes</span> and tsunamis around the world have heightened awareness of the inevitability of similar events occurring within the Cascadia Subduction Zone of the Pacific Northwest. We analyzed seafloor temperature, pressure, and seismic signals, and video stills of sediment-enveloped instruments recorded during the 2011–2015 Cascadia Initiative experiment, and seafloor morphology. Our results led us to suggest that thick accretionary prism sediments amplified and extended seismic wave durations from the 11 April 2012 Mw8.6 Indian Ocean <span class="hlt">earthquake</span>, located more than 13,500 km away. These waves triggered a sequence of small slope failures on the Cascadia margin that led to sediment gravity flows culminating in turbidity currents. Previous studies have related the triggering of sediment-laden gravity flows and turbidite deposition to local <span class="hlt">earthquakes</span>, but this is the first study in which the originating seismic event is extremely distant (> 10,000 km). The possibility of remotely triggered slope failures that generate sediment-laden gravity flows should be considered in inferences of <span class="hlt">recurrence</span> intervals of past great Cascadia <span class="hlt">earthquakes</span> from turbidite sequences. Future similar studies may provide new understanding of submarine slope failures and turbidity currents and the hazards they pose to seafloor infrastructure and tsunami generation in regions both with and without local <span class="hlt">earthquakes</span>.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22743956','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22743956"><span>A systematic review of complication and <span class="hlt">recurrence</span> <span class="hlt">rates</span> of musculocutaneous, fasciocutaneous, and perforator-based flaps for treatment of pressure sores.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sameem, Mojib; Au, Michael; Wood, Thomas; Farrokhyar, Forough; Mahoney, James</p> <p>2012-07-01</p> <p>Management of pressure sores poses a significant reconstructive challenge for plastic surgeons. Currently, there is no consensus on whether musculocutaneous, fasciocutaneous, or perforator-based flaps provide superior results for treating pressure sores. The following databases were searched: Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, LILACS (January of 1950 to November of 2010), MEDLINE (January of 1950 to November of 2010), and EMBASE (January of 1980 to November of 2010). Only articles reporting on the use of musculocutaneous, fasciocutaneous, and perforator-based flaps were included. The primary study outcomes were complication and <span class="hlt">recurrence</span> <span class="hlt">rates</span>. Fifty-five articles were included in the final analysis (kappa = 0.78). From this total, 28 were categorized as pertaining to musculocutaneous flaps, 13 studied fasciocutaneous flaps, and 14 evaluated perforator-based flaps. The authors' review revealed <span class="hlt">recurrence</span> and complication <span class="hlt">rates</span> of 8.9 and 18.6 percent, respectively, following reconstruction with musculocutaneous flaps, 11.2 and 11.7 percent following reconstruction with fasciocutaneous flaps, and 5.6 and 19.6 percent following reconstruction with perforator-based flaps. Overall, statistical analysis revealed no significant difference in complication or <span class="hlt">recurrence</span> <span class="hlt">rates</span> among these three techniques. The authors' review revealed that there was no statistically significant difference with regard to <span class="hlt">recurrence</span> or complication <span class="hlt">rates</span> among musculocutaneous, fasciocutaneous, or perforator-based flaps. This suggests that surgeons performing such reconstructive procedures may choose to consider the advantages of a specific approach rather than the complication and <span class="hlt">recurrence</span> <span class="hlt">rates</span>. Therapeutic, IV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27299734','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27299734"><span>Association of the <span class="hlt">recurrence</span> and canceration <span class="hlt">rate</span> of vocal leukoplakia with interleukin-10 promoter variants over a 2-year period.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhou, Jian; Zhang, Duo; Zhou, Liang; Yang, Yue; Liu, Fei; Tao, Lei; Lu, Li-Ming</p> <p>2016-11-01</p> <p>Conclusion This study indicates that IL-10 promoter polymorphism variants, smoking, and alcohol consumption increase the risk of <span class="hlt">recurrence</span> and canceration in vocal leukoplakia. Objective This prospective, clinical trial was performed to evaluate the association of interleukin (IL)-10 promoter polymorphism variants and canceration and <span class="hlt">recurrence</span> <span class="hlt">rates</span> in vocal leukoplakia (a pre-cancerous laryngeal carcinoma lesion) over a 2-year period. Participants and method Sixty-one post-operative patients with vocal leukoplakia were enrolled in this prospective, observational study and genotyped for the IL-10 promoter gene (IL-10-1082 A/G, -819 T/C and -592 A/C) using pyrosequencing, and responded to a 2-year follow-up survey. <span class="hlt">Recurrence</span> and canceration <span class="hlt">rates</span> were used to evaluate the association between the genotype variants and the clinical outcome. Results There was an increased canceration <span class="hlt">rate</span> in the variant genotype group compared to that in the normal genotype group in the 2-year follow-up period (18.4% vs 0%, p-value = 0.038). Compared with the non-smoker group, the smoker group had a higher <span class="hlt">recurrence</span> <span class="hlt">rate</span> of vocal leukoplakia (29.3% vs 5%, p-value =0.044). Likewise, the <span class="hlt">recurrence</span> <span class="hlt">rate</span> in the alcohol consumption group was also higher (30.6% vs 8%, p-value =0.034). The percentage of cancerization in the alcohol consumption group was significantly higher than that in the non-alcohol consumption group (19.4% vs 0%, p-value =0.035).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70012441','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70012441"><span>Evidence for the <span class="hlt">recurrence</span> of large-magnitude <span class="hlt">earthquakes</span> along the Makran coast of Iran and Pakistan</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Page, W.D.; Alt, J.N.; Cluff, L.S.; Plafker, G.</p> <p>1979-01-01</p> <p>The presence of raised beaches and marine terraces along the Makran coast indicates episodic uplift of the continental margin resulting from large-magnitude <span class="hlt">earthquakes</span>. The uplift occurs as incremental steps similar in height to the 1-3 m of measured uplift resulting from the November 28, 1945 (M 8.3) <span class="hlt">earthquake</span> at Pasni and Ormara, Pakistan. The data support an E-W-trending, active subduction zone off the Makran coast. The raised beaches and wave-cut terraces along the Makran coast are extensive with some terraces 1-2 km wide, 10-15 m long and up to 500 m in elevation. The terraces are generally capped with shelly sandstones 0.5-5 m thick. Wave-cut cliffs, notches, and associated boulder breccia and swash troughs are locally preserved. Raised Holocene accretion beaches, lagoonal deposits, and tombolos are found up to 10 m in elevation. The number and elevation of raised wave-cut terraces along the Makran coast increase eastward from one at Jask, the entrance to the Persian Gulf, at a few meters elevation, to nine at Konarak, 250 km to the east. Multiple terraces are found on the prominent headlands as far east as Karachi. The wave-cut terraces are locally tilted and cut by faults with a few meters of displacement. Long-term, average <span class="hlt">rates</span> of uplift were calculated from present elevation, estimated elevation at time of deposition, and 14C and U-Th dates obtained on shells. Uplift <span class="hlt">rates</span> in centimeters per year at various locations from west to east are as follows: Jask, 0 (post-Sangamon); Konarak, 0.031-0.2 (Holocene), 0.01 (post-Sangamon); Ormara 0.2 (Holocene). ?? 1979.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.S52A..08J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.S52A..08J"><span>Geophysical Anomalies and <span class="hlt">Earthquake</span> Prediction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jackson, D. D.</p> <p>2008-12-01</p> <p>Finding anomalies is easy. Predicting <span class="hlt">earthquakes</span> convincingly from such anomalies is far from easy. Why? Why have so many beautiful geophysical abnormalities not led to successful prediction strategies? What is <span class="hlt">earthquake</span> prediction? By my definition it is convincing information that an <span class="hlt">earthquake</span> of specified size is temporarily much more likely than usual in a specific region for a specified time interval. We know a lot about normal <span class="hlt">earthquake</span> behavior, including locations where <span class="hlt">earthquake</span> <span class="hlt">rates</span> are higher than elsewhere, with estimable <span class="hlt">rates</span> and size distributions. We know that <span class="hlt">earthquakes</span> have power law size distributions over large areas, that they cluster in time and space, and that aftershocks follow with power-law dependence on time. These relationships justify prudent protective measures and scientific investigation. <span class="hlt">Earthquake</span> prediction would justify exceptional temporary measures well beyond those normal prudent actions. Convincing <span class="hlt">earthquake</span> prediction would result from methods that have demonstrated many successes with few false alarms. Predicting <span class="hlt">earthquakes</span> convincingly is difficult for several profound reasons. First, <span class="hlt">earthquakes</span> start in tiny volumes at inaccessible depth. The power law size dependence means that tiny unobservable ones are frequent almost everywhere and occasionally grow to larger size. Thus prediction of important <span class="hlt">earthquakes</span> is not about nucleation, but about identifying the conditions for growth. Second, <span class="hlt">earthquakes</span> are complex. They derive their energy from stress, which is perniciously hard to estimate or model because it is nearly singular at the margins of cracks and faults. Physical properties vary from place to place, so the preparatory processes certainly vary as well. Thus establishing the needed track record for validation is very difficult, especially for large events with immense interval times in any one location. Third, the anomalies are generally complex as well. Electromagnetic anomalies in particular require</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70147090','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70147090"><span>Time‐dependent renewal‐model probabilities when date of last <span class="hlt">earthquake</span> is unknown</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Field, Edward H.; Jordan, Thomas H.</p> <p>2015-01-01</p> <p>We derive time-dependent, renewal-model <span class="hlt">earthquake</span> probabilities for the case in which the date of the last event is completely unknown, and compare these with the time-independent Poisson probabilities that are customarily used as an approximation in this situation. For typical parameter values, the renewal-model probabilities exceed Poisson results by more than 10% when the forecast duration exceeds ~20% of the mean <span class="hlt">recurrence</span> interval. We also derive probabilities for the case in which the last event is further constrained to have occurred before historical record keeping began (the historic open interval), which can only serve to increase <span class="hlt">earthquake</span> probabilities for typically applied renewal models.We conclude that accounting for the historic open interval can improve long-term <span class="hlt">earthquake</span> rupture forecasts for California and elsewhere.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27349259','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27349259"><span>Predictors of psychological resilience amongst medical students following major <span class="hlt">earthquakes</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carter, Frances; Bell, Caroline; Ali, Anthony; McKenzie, Janice; Boden, Joseph M; Wilkinson, Timothy; Bell, Caroline</p> <p>2016-05-06</p> <p>To identify predictors of self-reported psychological resilience amongst medical students following major <span class="hlt">earthquakes</span> in Canterbury in 2010 and 2011. Two hundred and fifty-three medical students from the Christchurch campus, University of Otago, were invited to participate in an electronic survey seven months following the most severe <span class="hlt">earthquake</span>. Students completed the Connor-Davidson Resilience Scale, the Depression, Anxiety and Stress Scale, the Post-traumatic Disorder Checklist, the Work and Adjustment Scale, and the Eysenck Personality Questionnaire. Likert scales and other questions were also used to assess a range of variables including demographic and historical variables (eg, self-<span class="hlt">rated</span> resilience prior to the <span class="hlt">earthquakes</span>), plus the impacts of the <span class="hlt">earthquakes</span>. The response <span class="hlt">rate</span> was 78%. Univariate analyses identified multiple variables that were significantly associated with higher resilience. Multiple linear regression analyses produced a fitted model that was able to explain 35% of the variance in resilience scores. The best predictors of higher resilience were: retrospectively-<span class="hlt">rated</span> personality prior to the <span class="hlt">earthquakes</span> (higher extroversion and lower neuroticism); higher self-<span class="hlt">rated</span> resilience prior to the <span class="hlt">earthquakes</span>; not being exposed to the most severe <span class="hlt">earthquake</span>; and less psychological distress following the <span class="hlt">earthquakes</span>. Psychological resilience amongst medical students following major <span class="hlt">earthquakes</span> was able to be predicted to a moderate extent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036563','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036563"><span>Seismicity <span class="hlt">rate</span> changes along the central California coast due to stress changes from the 2003 M 6.5 San Simeon and 2004 M 6.0 Parkfield <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Aron, A.; Hardebeck, J.L.</p> <p>2009-01-01</p> <p>We investigated the relationship between seismicity <span class="hlt">rate</span> changes and modeled Coulomb static stress changes from the 2003 M 6.5 San Simeon and the 2004 M 6.0 Parkfield <span class="hlt">earthquakes</span> in central California. Coulomb stress modeling indicates that the San Simeon mainshock loaded parts of the Rinconada, Hosgri, and San Andreas strike-slip faults, along with the reverse faults of the southern Los Osos domain. All of these loaded faults, except for the San Andreas, experienced a seismicity <span class="hlt">rate</span> increase at the time of the San Simeon mainshock. The Parkfield <span class="hlt">earthquake</span> occurred 9 months later on the loaded portion of the San Andreas fault. The Parkfield <span class="hlt">earthquake</span> unloaded the Hosgri fault and the reverse faults of the southern Los Osos domain, which both experienced seismicity <span class="hlt">rate</span> decreases at the time of the Parkfield event, although the decreases may be related to the decay of San Simeon-triggered seismicity. Coulomb stress unloading from the Parkfield <span class="hlt">earthquake</span> appears to have altered the aftershock decay <span class="hlt">rate</span> of the southern cluster of San Simeon after-shocks, which is deficient compared to the expected number of aftershocks from the Omori decay parameters based on the pre-Parkfield aftershocks. Dynamic stress changes cannot explain the deficiency of aftershocks, providing evidence that static stress changes affect <span class="hlt">earthquake</span> occurrence. However, a burst of seismicity following the Parkfield <span class="hlt">earthquake</span> at Ragged Point, where the static stress was decreased, provides evidence for dynamic stress triggering. It therefore appears that both Coulomb static stress changes and dynamic stress changes affect the seismicity <span class="hlt">rate</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28543429','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28543429"><span><span class="hlt">Earthquake</span> insurance pricing: a risk-based approach.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lin, Jeng-Hsiang</p> <p>2018-04-01</p> <p>Flat <span class="hlt">earthquake</span> premiums are 'uniformly' set for a variety of buildings in many countries, neglecting the fact that the risk of damage to buildings by <span class="hlt">earthquakes</span> is based on a wide range of factors. How these factors influence the insurance premiums is worth being studied further. Proposed herein is a risk-based approach to estimate the <span class="hlt">earthquake</span> insurance <span class="hlt">rates</span> of buildings. Examples of application of the approach to buildings located in Taipei city of Taiwan were examined. Then, the <span class="hlt">earthquake</span> insurance <span class="hlt">rates</span> for the buildings investigated were calculated and tabulated. To fulfil insurance <span class="hlt">rating</span>, the buildings were classified into 15 model building types according to their construction materials and building height. Seismic design levels were also considered in insurance <span class="hlt">rating</span> in response to the effect of seismic zone and construction years of buildings. This paper may be of interest to insurers, actuaries, and private and public sectors of insurance. © 2018 The Author(s). Disasters © Overseas Development Institute, 2018.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S51B2684L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S51B2684L"><span>Dynamic Simulation of the 2011 M9.0 Tohoku <span class="hlt">Earthquake</span> with Geometric Complexity on a <span class="hlt">Rate</span>- and State-dependent Subduction Plane</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luo, B.; Duan, B.</p> <p>2015-12-01</p> <p>The Mw 9.0 Tohoku megathrust <span class="hlt">earthquake</span> on 11 March 2011 is a great surprise to the scientific community due to its unexpected occurrence on the subduction zone of Japan Trench where <span class="hlt">earthquakes</span> of magnitude ~7 to 8 are expected based on historical records. Slip distribution and kinematic slip history inverted from seismic data, GPS and tsunami recordings reveal two major aspects of this big event: a strong asperity near the hypocenter and large slip near the trench. To investigate physical conditions of these two aspects, we perform dynamic rupture simulations on a shallow-dipping <span class="hlt">rate</span>- and state-dependent subduction plane with topographic relief. Although existence of a subducted seamount just up-dip of the hypocenter is still an open question, high Vp anomalies [Zhao et al., 2011] and low Vp/Vs anomalies [Yamamoto et al., 2014] there strongly suggest some kind of topographic relief exists there. We explicitly incorporate a subducted seamount on the subduction surface into our models. Our preliminary results show that the subducted seamount play a significant role in dynamic rupture propagation due to the alteration of the stress state around it. We find that a subducted seamount can act as a strong barrier to many <span class="hlt">earthquakes</span>, but its ultimate failure after some <span class="hlt">earthquake</span> cycles results in giant <span class="hlt">earthquakes</span>. Its failure gives rise to large stress drop, resulting in a strong asperity in slip distribution as revealed in kinematic inversions. Our preliminary results also suggest that the <span class="hlt">rate</span>- and state- friction law plays an important role in rupture propagation of geometrically complex faults. Although <span class="hlt">rate</span>-strengthening behavior near the trench impedes rupture propagation, an energetic rupture can break such a barrier and manage to reach the trench, resulting in significant uplift at seafloor and hence devastating tsunami to human society.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27475479','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27475479"><span>High-dose-<span class="hlt">rate</span> interstitial brachytherapy for the treatment of high-volume locally <span class="hlt">recurrent</span> endometrial carcinoma.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huang, Kitty; D'Souza, David; Patil, Nikhilesh; Velker, Vikram; Leung, Eric; Stitt, Larry; Whiston, Frances; Sugimoto, Akira; McGee, Jacob; Prefontaine, Michel</p> <p>2016-01-01</p> <p>Limited therapeutic options are available for the treatment of locally <span class="hlt">recurrent</span> endometrial carcinoma. Our objective was to report an institutional experience using interstitial brachytherapy (IBT) to treat significant <span class="hlt">recurrent</span> endometrial carcinoma, including previously irradiated disease. Between December 2004 and September 2012, 40 patients with high-volume locally <span class="hlt">recurrent</span> endometrial cancer were treated by high-dose-<span class="hlt">rate</span> IBT (± external beam radiation therapy EBRT). Sixteen patients had prior radiotherapy: EBRT alone (n = 5), intracavitary brachytherapy alone (n = 3), or EBRT with intracavitary brachytherapy boost (n = 8). Actuarial outcome <span class="hlt">rates</span> were calculated using the Kaplan-Meier method and compared using the log-rank test. Median followup interval was 18 months. Median disease-free interval was 61 months. Actuarial local control, progression-free survival (PFS), and overall survival were 74% and 60%, 70% and 51%, and 83% and 72% at 12 and 24 months, respectively. p-Values for local control, progression-free survival, and overall survival between patient who had prior RT (n = 16) to no prior RT (n = 24) were p = 0.38, 0.32, and 0.90, respectively. Acute toxicities include Grade 1-2 pain (5%), genitourinary (7%), gastrointestinal (12%), soft tissue (5%), and dermatologic (12%). Four patients observed late Grade 3-4 toxicities, including rectal bleeding/fistula and soft tissue necrosis. High-dose-<span class="hlt">rate</span> IBT is an effective treatment for locally <span class="hlt">recurrent</span> endometrial carcinoma with an acceptable toxicity profile. Outcomes are similar between previously irradiated and nonirradiated patients. In women who have received prior radiotherapy and are often considered for palliative treatment, interstitial brachytherapy is a potentially curative option. Copyright © 2016 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.7281H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.7281H"><span>On the Distribution of <span class="hlt">Earthquake</span> Interevent Times and the Impact of Spatial Scale</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hristopulos, Dionissios</p> <p>2013-04-01</p> <p>The distribution of <span class="hlt">earthquake</span> interevent times is a subject that has attracted much attention in the statistical physics literature [1-3]. A recent paper proposes that the distribution of <span class="hlt">earthquake</span> interevent times follows from the the interplay of the crustal strength distribution and the loading function (stress versus time) of the Earth's crust locally [4]. It was also shown that the Weibull distribution describes <span class="hlt">earthquake</span> interevent times provided that the crustal strength also follows the Weibull distribution and that the loading function follows a power-law during the loading cycle. I will discuss the implications of this work and will present supporting evidence based on the analysis of data from seismic catalogs. I will also discuss the theoretical evidence in support of the Weibull distribution based on models of statistical physics [5]. Since other-than-Weibull interevent times distributions are not excluded in [4], I will illustrate the use of the Kolmogorov-Smirnov test in order to determine which probability distributions are not rejected by the data. Finally, we propose a modification of the Weibull distribution if the size of the system under investigation (i.e., the area over which the <span class="hlt">earthquake</span> activity occurs) is finite with respect to a critical link size. keywords: hypothesis testing, modified Weibull, hazard <span class="hlt">rate</span>, finite size References [1] Corral, A., 2004. Long-term clustering, scaling, and universality in the temporal occurrence of <span class="hlt">earthquakes</span>, Phys. Rev. Lett., 9210) art. no. 108501. [2] Saichev, A., Sornette, D. 2007. Theory of <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> times, J. Geophys. Res., Ser. B 112, B04313/1-26. [3] Touati, S., Naylor, M., Main, I.G., 2009. Origin and nonuniversality of the <span class="hlt">earthquake</span> interevent time distribution Phys. Rev. Lett., 102 (16), art. no. 168501. [4] Hristopulos, D.T., 2003. Spartan Gibbs random field models for geostatistical applications, SIAM Jour. Sci. Comput., 24, 2125-2162. [5] I. Eliazar and J. Klafter, 2006</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12058296','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12058296"><span>[Does intraoperative nerve monitoring reduce the <span class="hlt">rate</span> of <span class="hlt">recurrent</span> nerve palsies during thyroid surgery?].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Timmermann, W; Dralle, H; Hamelmann, W; Thomusch, O; Sekulla, C; Meyer, Th; Timm, S; Thiede, A</p> <p>2002-05-01</p> <p>Two different aspects of the influence of neuromonitoring on the possible reduction of post-operative <span class="hlt">recurrent</span> laryngeal nerve palsies require critical examination: the nerve identification and the monitoring of it's functions. Due to the additional information from the EMG signals, neuromonitoring is the best method for identifying the nerves as compared to visual identification alone. There are still no randomized studies available that compare the visual and electrophysiological <span class="hlt">recurrent</span> laryngeal nerve detection in thyroid operations with respect to the postoperative nerve palsies. Nevertheless, comparisons with historical collectives show that a constant low nerve-palsy-<span class="hlt">rate</span> was achieved with electrophysiological detection in comparison to visual detection. The <span class="hlt">rate</span> of nerve identification is normally very high and amounts to 99 % in our own patients. The data obtained during the "Quality assurance of benign and malignant Goiter" study show that in hemithyreoidectomy and subtotal resection, lower nerve-palsy-<span class="hlt">rates</span> are achieved with neuromonitoring as compared to solely visual detection. Following subtotal resection, this discrepancy becomes even statistically significant. While monitoring the nerve functions with the presently used neuromonitoring technique, it is possible to observe the EMG-signal remaining constant or decreasing in volume. Assuming that a constant neuromonitoring signal represents a normal vocal cord, our evaluation shows that there is a small percentage of false negative and positive results. Looking at the permanent <span class="hlt">recurrent</span> nerve palsy <span class="hlt">rates</span>, this method has a specificity of 98 %, a sensitivity of 100 %, a positive prognostic value of 10 %, and a negative prognostic value of 100 %. Although an altered neuromonitoring signal can be taken as a clear indication of eventual nerve damage, an absolutely reliable statement about the postoperative vocal cord function is presently not possible with intraoperative neuromonitoring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoJI.212.1331N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoJI.212.1331N"><span><span class="hlt">Earthquake</span> triggering in southeast Africa following the 2012 Indian Ocean <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Neves, Miguel; Custódio, Susana; Peng, Zhigang; Ayorinde, Adebayo</p> <p>2018-02-01</p> <p>In this paper we present evidence of <span class="hlt">earthquake</span> dynamic triggering in southeast Africa. We analysed seismic waveforms recorded at 53 broad-band and short-period stations in order to identify possible increases in the <span class="hlt">rate</span> of microearthquakes and tremor due to the passage of teleseismic waves generated by the Mw8.6 2012 Indian Ocean <span class="hlt">earthquake</span>. We found evidence of triggered local <span class="hlt">earthquakes</span> and no evidence of triggered tremor in the region. We assessed the statistical significance of the increase in the number of local <span class="hlt">earthquakes</span> using β-statistics. Statistically significant dynamic triggering of local <span class="hlt">earthquakes</span> was observed at 7 out of the 53 analysed stations. Two of these stations are located in the northeast coast of Madagascar and the other five stations are located in the Kaapvaal Craton, southern Africa. We found no evidence of dynamically triggered seismic activity in stations located near the structures of the East African Rift System. Hydrothermal activity exists close to the stations that recorded dynamic triggering, however, it also exists near the East African Rift System structures where no triggering was observed. Our results suggest that factors other than solely tectonic regime and geothermalism are needed to explain the mechanisms that underlie <span class="hlt">earthquake</span> triggering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFMNH13B..08H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFMNH13B..08H"><span>Highly variable <span class="hlt">recurrence</span> of tsunamis in the 7,400 years before the 2004 Indian Ocean tsunami</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Horton, B.; Rubin, C. M.; Sieh, K.; Jessica, P.; Daly, P.; Ismail, N.; Parnell, A. C.</p> <p>2017-12-01</p> <p>The devastating 2004 Indian Ocean tsunami caught millions of coastal residents and the scientific community off-guard. Subsequent research in the Indian Ocean basin has identified prehistoric tsunamis, but the timing and <span class="hlt">recurrence</span> intervals of such events are uncertain. Here, we identify coastal caves as a new depositional environment for reconstructing tsunami records and present a 5,000 year record of continuous tsunami deposits from a coastal cave in Sumatra, Indonesia which shows the irregular <span class="hlt">recurrence</span> of 11 tsunamis between 7,400 and 2,900 years BP. The data demonstrates that the 2004 tsunami was just the latest in a sequence of devastating tsunamis stretching back to at least the early Holocene and suggests a high likelihood for future tsunamis in the Indian Ocean. The sedimentary record in the cave shows that ruptures of the Sunda megathrust vary between large (which generated the 2004 Indian Ocean tsunami) and smaller slip failures. The chronology of events suggests the <span class="hlt">recurrence</span> of multiple smaller tsunamis within relatively short time periods, interrupted by long periods of strain accumulation followed by giant tsunamis. The average time period between tsunamis is about 450 years with intervals ranging from a long, dormant period of over 2,000 years, to multiple tsunamis within the span of a century. The very long dormant period suggests that the Sunda megathrust is capable of accumulating large slip deficits between <span class="hlt">earthquakes</span>. Such a high slip rupture would produce a substantially larger <span class="hlt">earthquake</span> than the 2004 event. Although there is evidence that the likelihood of another tsunamigenic <span class="hlt">earthquake</span> in Aceh province is high, these variable <span class="hlt">recurrence</span> intervals suggest that long dormant periods may follow Sunda Megathrust ruptures as large as that of 2004 Indian Ocean tsunami. The remarkable variability of <span class="hlt">recurrence</span> suggests that regional hazard mitigation plans should be based upon the high likelihood of future destructive tsunami demonstrated by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70176033','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70176033"><span>Spatial-temporal variation of low-frequency <span class="hlt">earthquake</span> bursts near Parkfield, California</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wu, Chunquan; Guyer, Robert; Shelly, David R.; Trugman, D.; Frank, William; Gomberg, Joan S.; Johnson, P.</p> <p>2015-01-01</p> <p>Tectonic tremor (TT) and low-frequency <span class="hlt">earthquakes</span> (LFEs) have been found in the deeper crust of various tectonic environments globally in the last decade. The spatial-temporal behaviour of LFEs provides insight into deep fault zone processes. In this study, we examine <span class="hlt">recurrence</span> times from a 12-yr catalogue of 88 LFE families with ∼730 000 LFEs in the vicinity of the Parkfield section of the San Andreas Fault (SAF) in central California. We apply an automatic burst detection algorithm to the LFE <span class="hlt">recurrence</span> times to identify the clustering behaviour of LFEs (LFE bursts) in each family. We find that the burst behaviours in the northern and southern LFE groups differ. Generally, the northern group has longer burst duration but fewer LFEs per burst, while the southern group has shorter burst duration but more LFEs per burst. The southern group LFE bursts are generally more correlated than the northern group, suggesting more coherent deep fault slip and relatively simpler deep fault structure beneath the locked section of SAF. We also found that the 2004 Parkfield <span class="hlt">earthquake</span> clearly increased the number of LFEs per burst and average burst duration for both the northern and the southern groups, with a relatively larger effect on the northern group. This could be due to the weakness of northern part of the fault, or the northwesterly rupture direction of the Parkfield <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27885027','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27885027"><span>Mega-<span class="hlt">earthquakes</span> rupture flat megathrusts.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bletery, Quentin; Thomas, Amanda M; Rempel, Alan W; Karlstrom, Leif; Sladen, Anthony; De Barros, Louis</p> <p>2016-11-25</p> <p>The 2004 Sumatra-Andaman and 2011 Tohoku-Oki <span class="hlt">earthquakes</span> highlighted gaps in our understanding of mega-<span class="hlt">earthquake</span> rupture processes and the factors controlling their global distribution: A fast convergence <span class="hlt">rate</span> and young buoyant lithosphere are not required to produce mega-<span class="hlt">earthquakes</span>. We calculated the curvature along the major subduction zones of the world, showing that mega-<span class="hlt">earthquakes</span> preferentially rupture flat (low-curvature) interfaces. A simplified analytic model demonstrates that heterogeneity in shear strength increases with curvature. Shear strength on flat megathrusts is more homogeneous, and hence more likely to be exceeded simultaneously over large areas, than on highly curved faults. Copyright © 2016, American Association for the Advancement of Science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28479479','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28479479"><span>Direct Vision Internal Urethrotomy for Short Anterior Urethral Strictures and Beyond: Success <span class="hlt">Rates</span>, Predictors of Treatment Failure, and <span class="hlt">Recurrence</span> Management.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kluth, Luis A; Ernst, Lukas; Vetterlein, Malte W; Meyer, Christian P; Reiss, C Philip; Fisch, Margit; Rosenbaum, Clemens M</p> <p>2017-08-01</p> <p>To determine success <span class="hlt">rates</span>, predictors of <span class="hlt">recurrence</span>, and <span class="hlt">recurrence</span> management of patients treated for short anterior urethral strictures by direct vision internal urethrotomy (DVIU). We identified 128 patients who underwent DVIU of the anterior urethra between December 2009 and March 2016. Follow-up was conducted by telephone interviews. Success <span class="hlt">rates</span> were assessed by Kaplan-Meier estimators. Predictors of stricture <span class="hlt">recurrence</span> and different further therapy strategies were identified by uni- and multivariable Cox regression analyses. The mean age was 63.8 years (standard deviation: 16.3) and the overall success <span class="hlt">rate</span> was 51.6% (N = 66) at a median follow-up of 16 months (interquartile range: 6-43). Median time to stricture <span class="hlt">recurrence</span> was six months (interquartile range: 2-12). In uni- and multivariable analyses, only repeat DVIU (hazard ratio [HR] = 1.87, 95% confidence interval (CI) = 1.13-3.11, P= .015; and HR=1.78, 95% CI = 1.05-3.03, P = .032, respectively) was a risk factor for <span class="hlt">recurrence</span>. Of 62 patients with <span class="hlt">recurrence</span>, 35.5% underwent urethroplasty, 29% underwent further endoscopic treatment, and 33.9% did not undergo further interventional therapy. Age (HR = 1.05, 95% CI = 1.01-1.09, P = .019) and diabetes (HR = 2.90, 95% CI = 1.02-8.26, P = .047) were predictors of no further interventional therapy. DVIU seems justifiable in short urethral strictures as a primary treatment. Prior DVIU was a risk factor for <span class="hlt">recurrence</span>. In case of <span class="hlt">recurrence</span>, about one-third of the patients did not undergo any further therapy. Higher age and diabetes predicted the denial of any further treatment. Copyright © 2017 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.3586B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.3586B"><span>Bayesian probabilities for Mw 9.0+ <span class="hlt">earthquakes</span> in the Aleutian Islands from a regionally scaled global <span class="hlt">rate</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Butler, Rhett; Frazer, L. Neil; Templeton, William J.</p> <p>2016-05-01</p> <p>We use the global <span class="hlt">rate</span> of Mw ≥ 9.0 <span class="hlt">earthquakes</span>, and standard Bayesian procedures, to estimate the probability of such mega events in the Aleutian Islands, where they pose a significant risk to Hawaii. We find that the probability of such an <span class="hlt">earthquake</span> along the Aleutians island arc is 6.5% to 12% over the next 50 years (50% credibility interval) and that the annualized risk to Hawai'i is about $30 M. Our method (the regionally scaled global <span class="hlt">rate</span> method or RSGR) is to scale the global <span class="hlt">rate</span> of Mw 9.0+ events in proportion to the fraction of global subduction (units of area per year) that takes place in the Aleutians. The RSGR method assumes that Mw 9.0+ events are a Poisson process with a <span class="hlt">rate</span> that is both globally and regionally stationary on the time scale of centuries, and it follows the principle of Burbidge et al. (2008) who used the product of fault length and convergence <span class="hlt">rate</span>, i.e., the area being subducted per annum, to scale the Poisson <span class="hlt">rate</span> for the GSS to sections of the Indonesian subduction zone. Before applying RSGR to the Aleutians, we first apply it to five other regions of the global subduction system where its <span class="hlt">rate</span> predictions can be compared with those from paleotsunami, paleoseismic, and geoarcheology data. To obtain regional <span class="hlt">rates</span> from paleodata, we give a closed-form solution for the probability density function of the Poisson <span class="hlt">rate</span> when event count and observation time are both uncertain.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMNH51A3835M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMNH51A3835M"><span><span class="hlt">Earthquake</span> Safety Tips in the Classroom</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melo, M. O.; Maciel, B. A. P. C.; Neto, R. P.; Hartmann, R. P.; Marques, G.; Gonçalves, M.; Rocha, F. L.; Silveira, G. M.</p> <p>2014-12-01</p> <p>The catastrophes induced by <span class="hlt">earthquakes</span> are among the most devastating ones, causing an elevated number of human losses and economic damages. But, we have to keep in mind that <span class="hlt">earthquakes</span> don't kill people, buildings do. <span class="hlt">Earthquakes</span> can't be predicted and the only way of dealing with their effects is to teach the society how to be prepared for them, and how to deal with their consequences. In spite of being exposed to moderate and large <span class="hlt">earthquakes</span>, most of the Portuguese are little aware of seismic risk, mainly due to the long <span class="hlt">recurrence</span> intervals between strong events. The acquisition of safe and correct attitudes before, during and after an <span class="hlt">earthquake</span> is relevant for human security. Children play a determinant role in the establishment of a real and long-lasting "culture of prevention", both through action and new attitudes. On the other hand, when children assume correct behaviors, their relatives often change their incorrect behaviors to mimic the correct behaviors of their kids. In the framework of a Parents-in-Science initiative, we started with bi-monthly sessions for children aged 5 - 6 years old and 9 - 10 years old. These sessions, in which parents, teachers and high-school students participate, became part of the school's permanent activities. We start by a short introduction to the Earth and to <span class="hlt">earthquakes</span> by story telling and by using simple science activities to trigger children curiosity. With safety purposes, we focus on how crucial it is to know basic information about themselves and to define, with their families, an emergency communications plan, in case family members are separated. Using a shaking table we teach them how to protect themselves during an <span class="hlt">earthquake</span>. We then finish with the preparation on an individual emergency kit. This presentation will highlight the importance of encouraging preventive actions in order to reduce the impact of <span class="hlt">earthquakes</span> on society. This project is developed by science high-school students and teachers, in</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70156107','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70156107"><span>Is there a basis for preferring characteristic <span class="hlt">earthquakes</span> over a Gutenberg–Richter distribution in probabilistic <span class="hlt">earthquake</span> forecasting?</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Parsons, Thomas E.; Geist, Eric L.</p> <p>2009-01-01</p> <p>The idea that faults rupture in repeated, characteristic <span class="hlt">earthquakes</span> is central to most probabilistic <span class="hlt">earthquake</span> forecasts. The concept is elegant in its simplicity, and if the same event has repeated itself multiple times in the past, we might anticipate the next. In practice however, assembling a fault-segmented characteristic <span class="hlt">earthquake</span> rupture model can grow into a complex task laden with unquantified uncertainty. We weigh the evidence that supports characteristic <span class="hlt">earthquakes</span> against a potentially simpler model made from extrapolation of a Gutenberg–Richter magnitude-frequency law to individual fault zones. We find that the Gutenberg–Richter model satisfies key data constraints used for <span class="hlt">earthquake</span> forecasting equally well as a characteristic model. Therefore, judicious use of instrumental and historical <span class="hlt">earthquake</span> catalogs enables large-<span class="hlt">earthquake-rate</span> calculations with quantifiable uncertainty that should get at least equal weighting in probabilistic forecasting.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25345405','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25345405"><span>Regression analysis of mixed <span class="hlt">recurrent</span>-event and panel-count data with additive <span class="hlt">rate</span> models.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhu, Liang; Zhao, Hui; Sun, Jianguo; Leisenring, Wendy; Robison, Leslie L</p> <p>2015-03-01</p> <p>Event-history studies of <span class="hlt">recurrent</span> events are often conducted in fields such as demography, epidemiology, medicine, and social sciences (Cook and Lawless, 2007, The Statistical Analysis of <span class="hlt">Recurrent</span> Events. New York: Springer-Verlag; Zhao et al., 2011, Test 20, 1-42). For such analysis, two types of data have been extensively investigated: <span class="hlt">recurrent</span>-event data and panel-count data. However, in practice, one may face a third type of data, mixed <span class="hlt">recurrent</span>-event and panel-count data or mixed event-history data. Such data occur if some study subjects are monitored or observed continuously and thus provide <span class="hlt">recurrent</span>-event data, while the others are observed only at discrete times and hence give only panel-count data. A more general situation is that each subject is observed continuously over certain time periods but only at discrete times over other time periods. There exists little literature on the analysis of such mixed data except that published by Zhu et al. (2013, Statistics in Medicine 32, 1954-1963). In this article, we consider the regression analysis of mixed data using the additive <span class="hlt">rate</span> model and develop some estimating equation-based approaches to estimate the regression parameters of interest. Both finite sample and asymptotic properties of the resulting estimators are established, and the numerical studies suggest that the proposed methodology works well for practical situations. The approach is applied to a Childhood Cancer Survivor Study that motivated this study. © 2014, The International Biometric Society.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27418504','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27418504"><span>Connecting slow <span class="hlt">earthquakes</span> to huge <span class="hlt">earthquakes</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Obara, Kazushige; Kato, Aitaro</p> <p>2016-07-15</p> <p>Slow <span class="hlt">earthquakes</span> are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional <span class="hlt">earthquakes</span>. However, slow <span class="hlt">earthquakes</span> and huge megathrust <span class="hlt">earthquakes</span> can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow <span class="hlt">earthquakes</span> may help to reveal the physics underlying megathrust events as useful analogs. Slow <span class="hlt">earthquakes</span> may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge <span class="hlt">earthquakes</span> if the adjacent locked region is critically loaded. Careful and precise monitoring of slow <span class="hlt">earthquakes</span> may provide new information on the likelihood of impending huge <span class="hlt">earthquakes</span>. Copyright © 2016, American Association for the Advancement of Science.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23887595','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23887595"><span>Lower reoperation <span class="hlt">rate</span> for <span class="hlt">recurrence</span> after mesh versus sutured elective repair in small umbilical and epigastric hernias. A nationwide register study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Christoffersen, M W; Helgstrand, F; Rosenberg, J; Kehlet, H; Bisgaard, T</p> <p>2013-11-01</p> <p>Repair for a small (≤ 2 cm) umbilical and epigastric hernia is a minor surgical procedure. The most common surgical repair techniques are a sutured repair or a repair with mesh reinforcement. However, the optimal repair technique with regard to risk of reoperation for <span class="hlt">recurrence</span> is not well documented. The aim of the present study was in a nationwide setup to investigate the reoperation <span class="hlt">rate</span> for <span class="hlt">recurrence</span> after small open umbilical and epigastric hernia repairs using either sutured or mesh repair. This was a prospective cohort study based on intraoperative registrations from the Danish Ventral Hernia Database (DVHD) of patients undergoing elective open mesh and sutured repair for small (≤ 2 cm) umbilical and epigastric hernias. Patients were included during a 4-year study period. A complete follow-up was obtained by combining intraoperative data from the DVHD with data from the Danish National Patient Register. The cumulative reoperation <span class="hlt">rates</span> were obtained using cumulative incidence plot and compared with the log rank test. In total, 4,786 small (≤ 2 cm) elective open umbilical and epigastric hernia repairs were included. Age was median 48 years (range 18-95 years). Follow-up was 21 months (range 0-47 months). The cumulated reoperation <span class="hlt">rates</span> for <span class="hlt">recurrence</span> were 2.2 % for mesh reinforcement and 5.6 % for sutured repair (P = 0.001). The overall cumulated reoperation <span class="hlt">rate</span> for sutured and mesh repairs was 4.8 %. In conclusion, reoperation <span class="hlt">rate</span> for <span class="hlt">recurrence</span> for small umbilical and epigastric hernias was significantly lower after mesh repair compared with sutured repair. Mesh reinforcement should be routine in even small umbilical or epigastric hernias to lower the risk of reoperation for <span class="hlt">recurrence</span> avoid <span class="hlt">recurrence</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12241313','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12241313"><span><span class="hlt">Recurrence</span>-plot-based measures of complexity and their application to heart-<span class="hlt">rate</span>-variability data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marwan, Norbert; Wessel, Niels; Meyerfeldt, Udo; Schirdewan, Alexander; Kurths, Jürgen</p> <p>2002-08-01</p> <p>The knowledge of transitions between regular, laminar or chaotic behaviors is essential to understand the underlying mechanisms behind complex systems. While several linear approaches are often insufficient to describe such processes, there are several nonlinear methods that, however, require rather long time observations. To overcome these difficulties, we propose measures of complexity based on vertical structures in <span class="hlt">recurrence</span> plots and apply them to the logistic map as well as to heart-<span class="hlt">rate</span>-variability data. For the logistic map these measures enable us not only to detect transitions between chaotic and periodic states, but also to identify laminar states, i.e., chaos-chaos transitions. The traditional <span class="hlt">recurrence</span> quantification analysis fails to detect the latter transitions. Applying our measures to the heart-<span class="hlt">rate</span>-variability data, we are able to detect and quantify the laminar phases before a life-threatening cardiac arrhythmia occurs thereby facilitating a prediction of such an event. Our findings could be of importance for the therapy of malignant cardiac arrhythmias.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70037209','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70037209"><span>On near-source <span class="hlt">earthquake</span> triggering</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Parsons, T.; Velasco, A.A.</p> <p>2009-01-01</p> <p>When one <span class="hlt">earthquake</span> triggers others nearby, what connects them? Two processes are observed: static stress change from fault offset and dynamic stress changes from passing seismic waves. In the near-source region (r ??? 50 km for M ??? 5 sources) both processes may be operating, and since both mechanisms are expected to raise <span class="hlt">earthquake</span> <span class="hlt">rates</span>, it is difficult to isolate them. We thus compare explosions with <span class="hlt">earthquakes</span> because only <span class="hlt">earthquakes</span> cause significant static stress changes. We find that large explosions at the Nevada Test Site do not trigger <span class="hlt">earthquakes</span> at <span class="hlt">rates</span> comparable to similar magnitude <span class="hlt">earthquakes</span>. Surface waves are associated with regional and long-range dynamic triggering, but we note that surface waves with low enough frequency to penetrate to depths where most aftershocks of the 1992 M = 5.7 Little Skull Mountain main shock occurred (???12 km) would not have developed significant amplitude within a 50-km radius. We therefore focus on the best candidate phases to cause local dynamic triggering, direct waves that pass through observed near-source aftershock clusters. We examine these phases, which arrived at the nearest (200-270 km) broadband station before the surface wave train and could thus be isolated for study. Direct comparison of spectral amplitudes of presurface wave arrivals shows that M ??? 5 explosions and <span class="hlt">earthquakes</span> deliver the same peak dynamic stresses into the near-source crust. We conclude that a static stress change model can readily explain observed aftershock patterns, whereas it is difficult to attribute near-source triggering to a dynamic process because of the dearth of aftershocks near large explosions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25159038','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25159038"><span>Aneurysm <span class="hlt">Recurrence</span> Volumetry Is More Sensitive than Visual Evaluation of Aneurysm <span class="hlt">Recurrences</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schönfeld, M H; Schlotfeldt, V; Forkert, N D; Goebell, E; Groth, M; Vettorazzi, E; Cho, Y D; Han, M H; Kang, H-S; Fiehler, J</p> <p>2016-03-01</p> <p>Considerable inter-observer variability in the visual assessment of aneurysm <span class="hlt">recurrences</span> limits its use as an outcome parameter evaluating new coil generations. The purpose of this study was to compare visual assessment of aneurysm <span class="hlt">recurrences</span> and aneurysm <span class="hlt">recurrence</span> volumetry with an example dataset of HydroSoft coils (HSC) versus bare platinum coils (BPC). For this retrospective study, 3-dimensional time-of-flight magnetic resonance angiography datasets acquired 6 and 12 months after endovascular therapy using BPC only or mainly HSC were analyzed. Aneurysm <span class="hlt">recurrence</span> volumes were visually <span class="hlt">rated</span> by two observersas well as quantified by subtraction of the datasets after intensity-based rigid registration. A total of 297 aneurysms were analyzed (BPC: 169, HSC: 128). <span class="hlt">Recurrences</span> were detected by aneurysm <span class="hlt">recurrence</span> volumetry in 9 of 128 (7.0 %) treated with HSC and in 24 of 169 (14.2 %) treated with BPC (odds ratio: 2.39, 95 % confidence interval: 1.05-5.48; P = 0.039). Aneurysm <span class="hlt">recurrence</span> volumetry revealed an excellent correlation between observers (Cronbach's alpha = 0.93). In contrast, no significant difference in aneurysm <span class="hlt">recurrence</span> was found for visual assessment (3.9 % in HSC cases and 4.7 % in BPC cases). <span class="hlt">Recurrences</span> were observed in aneurysms smaller than the sample median in 10 of 33 (30.3 %) by aneurysm <span class="hlt">recurrence</span> volumetry and in 1 of 13 (7.7 %) by visual assessment. Aneurysm <span class="hlt">recurrences</span> were detected more frequently by aneurysm <span class="hlt">recurrence</span> volumetry when compared with visual assessment. By using aneurysm <span class="hlt">recurrence</span> volumetry, differences between treatment groups were detected with higher sensitivity and inter-observer validity probably because of the higher detection <span class="hlt">rate</span> of <span class="hlt">recurrences</span> in small aneurysms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22254904','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22254904"><span><span class="hlt">Recurrence</span> quantification analysis of heart <span class="hlt">rate</span> variability and respiratory flow series in patients on weaning trials.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Arcentales, Andrés; Giraldo, Beatriz F; Caminal, Pere; Benito, Salvador; Voss, Andreas</p> <p>2011-01-01</p> <p>Autonomic nervous system regulates the behavior of cardiac and respiratory systems. Its assessment during the ventilator weaning can provide information about physio-pathological imbalances. This work proposes a non linear analysis of the complexity of the heart <span class="hlt">rate</span> variability (HRV) and breathing duration (T(Tot)) applying <span class="hlt">recurrence</span> plot (RP) and their interaction joint <span class="hlt">recurrence</span> plot (JRP). A total of 131 patients on weaning trials from mechanical ventilation were analyzed: 92 patients with successful weaning (group S) and 39 patients that failed to maintain spontaneous breathing (group F). The results show that parameters as determinism (DET), average diagonal line length (L), and entropy (ENTR), are statistically significant with RP for T(Tot) series, but not with HRV. When comparing the groups with JRP, all parameters have been relevant. In all cases, mean values of <span class="hlt">recurrence</span> quantification analysis are higher in the group S than in the group F. The main differences between groups were found on the diagonal and vertical structures of the joint <span class="hlt">recurrence</span> plot.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70025583','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70025583"><span>Fault interaction and stress triggering of twentieth century <span class="hlt">earthquakes</span> in Mongolia</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Pollitz, F.; Vergnolle, M.; Calais, E.</p> <p>2003-01-01</p> <p>A cluster of exceptionally large <span class="hlt">earthquakes</span> in the interior of Asia occurred from 1905 to 1967: the 1905 M7.9 Tsetserleg and M8.4 Bolnai <span class="hlt">earthquakes</span>, the 1931 M8.0 Fu Yun <span class="hlt">earthquake</span>, the 1957 M8.1 Gobi-Altai <span class="hlt">earthquake</span>, and the 1967 M7.1 Mogod <span class="hlt">earthquake</span> (sequence). Each of the larger (M ??? 8) <span class="hlt">earthquakes</span> involved strike-slip faulting averaging more than 5 m and rupture lengths of several hundred kilometers. Available geologic data indicate that <span class="hlt">recurrence</span> intervals on the major source faults are several thousands of years and distances of about 400 km separate the respective rupture areas. We propose that the occurrences of these and many smaller <span class="hlt">earthquakes</span> are related and controlled to a large extent by stress changes generated by the compounded static deformation of the preceding <span class="hlt">earthquakes</span> and subsequent viscoelastic relaxation of the lower crust and upper mantle beneath Mongolia. We employ a spherically layered viscoelastic model constrained by the 1994-2002 GPS velocity field in western Mongolia [Vergnolle et al., 2003]. Using the succession of twentieth century <span class="hlt">earthquakes</span> as sources of deformation, we then analyze the time-dependent change in Coulomb failure stress (????f). At remote interaction distances, static ????f values are small. However, modeled postseismic stress changes typically accumulate to several tenths of a bar over time intervals of decades. Almost all significant twentieth century regional <span class="hlt">earthquakes</span> (M ??? 6) with well-constrained fault geometry lie in positive ????f lobes of magnitude about +0.5 bar. Our results suggest that significant stress transfer is possible among continental faults separated by hundreds of kilometers and on timescales of decades. Copyright 2003 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNG12A..06S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNG12A..06S"><span>Are <span class="hlt">Earthquakes</span> Predictable? A Study on Magnitude Correlations in <span class="hlt">Earthquake</span> Catalog and Experimental Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stavrianaki, K.; Ross, G.; Sammonds, P. R.</p> <p>2015-12-01</p> <p>The clustering of <span class="hlt">earthquakes</span> in time and space is widely accepted, however the existence of correlations in <span class="hlt">earthquake</span> magnitudes is more questionable. In standard models of seismic activity, it is usually assumed that magnitudes are independent and therefore in principle unpredictable. Our work seeks to test this assumption by analysing magnitude correlation between <span class="hlt">earthquakes</span> and their aftershocks. To separate mainshocks from aftershocks, we perform stochastic declustering based on the widely used Epidemic Type Aftershock Sequence (ETAS) model, which allows us to then compare the average magnitudes of aftershock sequences to that of their mainshock. The results of <span class="hlt">earthquake</span> magnitude correlations were compared with acoustic emissions (AE) from laboratory analog experiments, as fracturing generates both AE at the laboratory scale and <span class="hlt">earthquakes</span> on a crustal scale. Constant stress and constant strain <span class="hlt">rate</span> experiments were done on Darley Dale sandstone under confining pressure to simulate depth of burial. Microcracking activity inside the rock volume was analyzed by the AE technique as a proxy for <span class="hlt">earthquakes</span>. Applying the ETAS model to experimental data allowed us to validate our results and provide for the first time a holistic view on the correlation of <span class="hlt">earthquake</span> magnitudes. Additionally we search the relationship between the conditional intensity estimates of the ETAS model and the <span class="hlt">earthquake</span> magnitudes. A positive relation would suggest the existence of magnitude correlations. The aim of this study is to observe any trends of dependency between the magnitudes of aftershock <span class="hlt">earthquakes</span> and the <span class="hlt">earthquakes</span> that trigger them.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70010297','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70010297"><span>Prospects for <span class="hlt">earthquake</span> prediction and control</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Healy, J.H.; Lee, W.H.K.; Pakiser, L.C.; Raleigh, C.B.; Wood, M.D.</p> <p>1972-01-01</p> <p>The San Andreas fault is viewed, according to the concepts of seafloor spreading and plate tectonics, as a transform fault that separates the Pacific and North American plates and along which relative movements of 2 to 6 cm/year have been taking place. The resulting strain can be released by creep, by <span class="hlt">earthquakes</span> of moderate size, or (as near San Francisco and Los Angeles) by great <span class="hlt">earthquakes</span>. Microearthquakes, as mapped by a dense seismograph network in central California, generally coincide with zones of the San Andreas fault system that are creeping. Microearthquakes are few and scattered in zones where elastic energy is being stored. Changes in the <span class="hlt">rate</span> of strain, as recorded by tiltmeter arrays, have been observed before several <span class="hlt">earthquakes</span> of about magnitude 4. Changes in fluid pressure may control timing of seismic activity and make it possible to control natural <span class="hlt">earthquakes</span> by controlling variations in fluid pressure in fault zones. An experiment in <span class="hlt">earthquake</span> control is underway at the Rangely oil field in Colorado, where the <span class="hlt">rates</span> of fluid injection and withdrawal in experimental wells are being controlled. ?? 1972.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015E%26PSL.411..177M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015E%26PSL.411..177M"><span>Dual megathrust slip behaviors of the 2014 Iquique <span class="hlt">earthquake</span> sequence</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Meng, Lingsen; Huang, Hui; Bürgmann, Roland; Ampuero, Jean Paul; Strader, Anne</p> <p>2015-02-01</p> <p>The transition between seismic rupture and aseismic creep is of central interest to better understand the mechanics of subduction processes. A Mw 8.2 <span class="hlt">earthquake</span> occurred on April 1st, 2014 in the Iquique seismic gap of northern Chile. This event was preceded by a long foreshock sequence including a 2-week-long migration of seismicity initiated by a Mw 6.7 <span class="hlt">earthquake</span>. Repeating <span class="hlt">earthquakes</span> were found among the foreshock sequence that migrated towards the mainshock hypocenter, suggesting a large-scale slow-slip event on the megathrust preceding the mainshock. The variations of the <span class="hlt">recurrence</span> times of the repeating <span class="hlt">earthquakes</span> highlight the diverse seismic and aseismic slip behaviors on different megathrust segments. The repeaters that were active only before the mainshock recurred more often and were distributed in areas of substantial coseismic slip, while repeaters that occurred both before and after the mainshock were in the area complementary to the mainshock rupture. The spatiotemporal distribution of the repeating <span class="hlt">earthquakes</span> illustrates the essential role of propagating aseismic slip leading up to the mainshock and illuminates the distribution of postseismic afterslip. Various finite fault models indicate that the largest coseismic slip generally occurred down-dip from the foreshock activity and the mainshock hypocenter. Source imaging by teleseismic back-projection indicates an initial down-dip propagation stage followed by a rupture-expansion stage. In the first stage, the finite fault models show an emergent onset of moment <span class="hlt">rate</span> at low frequency (< 0.1 Hz), while back-projection shows a steady increase of high frequency power (> 0.5 Hz). This indicates frequency-dependent manifestations of seismic radiation in the low-stress foreshock region. In the second stage, the rupture expands in rich bursts along the rim of a semi-elliptical region with episodes of re-ruptures, suggesting delayed failure of asperities. The high-frequency rupture remains within an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JSeis..22..303P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JSeis..22..303P"><span>Temporal and spatial distributions of precursory seismicity <span class="hlt">rate</span> changes in the Thailand-Laos-Myanmar border region: implication for upcoming hazardous <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Puangjaktha, Prayot; Pailoplee, Santi</p> <p>2018-01-01</p> <p>To study the prospective areas of upcoming strong-to-major <span class="hlt">earthquakes</span>, i.e., M w ≥ 6.0, a catalog of seismicity in the vicinity of the Thailand-Laos-Myanmar border region was generated and then investigated statistically. Based on the successful investigations of previous works, the seismicity <span class="hlt">rate</span> change (Z value) technique was applied in this study. According to the completeness <span class="hlt">earthquake</span> dataset, eight available case studies of strong-to-major <span class="hlt">earthquakes</span> were investigated retrospectively. After iterative tests of the characteristic parameters concerning the number of <span class="hlt">earthquakes</span> ( N) and time window ( T w ), the values of 50 and 1.2 years, respectively, were found to reveal an anomalous high Z-value peak (seismic quiescence) prior to the occurrence of six out of the eight major <span class="hlt">earthquake</span> events studied. In addition, the location of the Z-value anomalies conformed fairly well to the epicenters of those <span class="hlt">earthquakes</span>. Based on the investigation of correlation coefficient and the stochastic test of the Z values, the parameters used here ( N = 50 events and T w = 1.2 years) were suitable to determine the precursory Z value and not random phenomena. The Z values of this study and the frequency-magnitude distribution b values of a previous work both highlighted the same prospective areas that might generate an upcoming major <span class="hlt">earthquake</span>: (i) some areas in the northern part of Laos and (ii) the eastern part of Myanmar.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017E%26PSL.472..253L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017E%26PSL.472..253L"><span><span class="hlt">Earthquakes</span> drive focused denudation along a tectonically active mountain front</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, Gen; West, A. Joshua; Densmore, Alexander L.; Jin, Zhangdong; Zhang, Fei; Wang, Jin; Clark, Marin; Hilton, Robert G.</p> <p>2017-08-01</p> <p><span class="hlt">Earthquakes</span> cause widespread landslides that can increase erosional fluxes observed over years to decades. However, the impact of <span class="hlt">earthquakes</span> on denudation over the longer timescales relevant to orogenic evolution remains elusive. Here we assess erosion associated with <span class="hlt">earthquake</span>-triggered landslides in the Longmen Shan range at the eastern margin of the Tibetan Plateau. We use the Mw 7.9 2008 Wenchuan and Mw 6.6 2013 Lushan <span class="hlt">earthquakes</span> to evaluate how seismicity contributes to the erosional budget from short timescales (annual to decadal, as recorded by sediment fluxes) to long timescales (kyr to Myr, from cosmogenic nuclides and low temperature thermochronology). Over this wide range of timescales, the highest <span class="hlt">rates</span> of denudation in the Longmen Shan coincide spatially with the region of most intense landsliding during the Wenchuan <span class="hlt">earthquake</span>. Across sixteen gauged river catchments, sediment flux-derived denudation <span class="hlt">rates</span> following the Wenchuan <span class="hlt">earthquake</span> are closely correlated with seismic ground motion and the associated volume of Wenchuan-triggered landslides (r2 > 0.6), and to a lesser extent with the frequency of high intensity runoff events (r2 = 0.36). To assess whether <span class="hlt">earthquake</span>-induced landsliding can contribute importantly to denudation over longer timescales, we model the total volume of landslides triggered by <span class="hlt">earthquakes</span> of various magnitudes over multiple <span class="hlt">earthquake</span> cycles. We combine models that predict the volumes of landslides triggered by <span class="hlt">earthquakes</span>, calibrated against the Wenchuan and Lushan events, with an <span class="hlt">earthquake</span> magnitude-frequency distribution. The long-term, landslide-sustained "seismic erosion <span class="hlt">rate</span>" is similar in magnitude to regional long-term denudation <span class="hlt">rates</span> (∼0.5-1 mm yr-1). The similar magnitude and spatial coincidence suggest that <span class="hlt">earthquake</span>-triggered landslides are a primary mechanism of long-term denudation in the frontal Longmen Shan. We propose that the location and intensity of seismogenic faulting can contribute to</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT........64T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT........64T"><span>Geodetic Imaging of the <span class="hlt">Earthquake</span> Cycle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tong, Xiaopeng</p> <p></p> <p>In this dissertation I used Interferometric Synthetic Aperture Radar (InSAR) and Global Positioning System (GPS) to recover crustal deformation caused by <span class="hlt">earthquake</span> cycle processes. The studied areas span three different types of tectonic boundaries: a continental thrust <span class="hlt">earthquake</span> (M7.9 Wenchuan, China) at the eastern margin of the Tibet plateau, a mega-thrust <span class="hlt">earthquake</span> (M8.8 Maule, Chile) at the Chile subduction zone, and the interseismic deformation of the San Andreas Fault System (SAFS). A new L-band radar onboard a Japanese satellite ALOS allows us to image high-resolution surface deformation in vegetated areas, which is not possible with older C-band radar systems. In particular, both the Wenchuan and Maule InSAR analyses involved L-band ScanSAR interferometry which had not been attempted before. I integrated a large InSAR dataset with dense GPS networks over the entire SAFS. The integration approach features combining the long-wavelength deformation from GPS with the short-wavelength deformation from InSAR through a physical model. The recovered fine-scale surface deformation leads us to better understand the underlying <span class="hlt">earthquake</span> cycle processes. The geodetic slip inversion reveals that the fault slip of the Wenchuan <span class="hlt">earthquake</span> is maximum near the surface and decreases with depth. The coseismic slip model of the Maule <span class="hlt">earthquake</span> constrains the down-dip extent of the fault slip to be at 45 km depth, similar to the Moho depth. I inverted for the slip <span class="hlt">rate</span> on 51 major faults of the SAFS using Green's functions for a 3-dimensional <span class="hlt">earthquake</span> cycle model that includes kinematically prescribed slip events for the past <span class="hlt">earthquakes</span> since the year 1000. A 60 km thick plate model with effective viscosity of 10 19 Pa · s is preferred based on the geodetic and geological observations. The slip <span class="hlt">rates</span> recovered from the plate models are compared to the half-space model. The InSAR observation reveals that the creeping section of the SAFS is partially locked. This high</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24217937','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24217937"><span>Long-term remission and <span class="hlt">recurrence</span> <span class="hlt">rates</span> after first and second transsphenoidal surgery for Cushing's disease: care reality in the Munich Metropolitan Region.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dimopoulou, C; Schopohl, J; Rachinger, W; Buchfelder, M; Honegger, J; Reincke, M; Stalla, G K</p> <p>2014-02-01</p> <p>Transsphenoidal surgery (TSS) presents the treatment of choice for Cushing's disease (CD). Remission and <span class="hlt">recurrence</span> <span class="hlt">rates</span> vary dependent on tumor size, extension, adenoma visibility on magnetic resonance imaging, and neurosurgical expertise. Other than published from single-surgeon neurosurgical series so far, we have aimed to describe long-term remission and <span class="hlt">recurrence</span> <span class="hlt">rates</span> of CD in a series incorporating different neurosurgeons, trying to reflect care reality in the Munich Metropolitan Region, which is accommodated by three tertiary university and multiple, smaller neurosurgical centers. We conducted a retrospective analysis of 120 patients who underwent first and 36 patients who underwent second TSS as treatment for CD between 1990 and 2012. Patients were divided into three groups according to remission status. Potential risk factors for <span class="hlt">recurrence</span>, pituitary function, and strategy in persistent disease were assessed. THREE OUTCOME GROUPS WERE IDENTIFIED ACCORDING TO REMISSION STATUS AFTER FIRST TSS (MEAN FOLLOW-UP 79 MONTHS): remission, 71% (85/120), disease persistence, 29% (35/120), and disease <span class="hlt">recurrence</span>, 34% (29/85) (mean time to <span class="hlt">recurrence</span> 54 months). After second TSS (n=36, mean follow-up 62 months), we documented remission in 42% (15/36), disease persistence in 58% (21/36), and disease <span class="hlt">recurrence</span> in 40% (6/15) (mean time to <span class="hlt">recurrence</span> 42 months). Postoperative hypocortisolism after first, though not after second, TSS was associated with a lower risk of suffering disease <span class="hlt">recurrence</span> (risk=0.72; 95% CI 0.60-0.88; exact significance (two-sided) P=0.035). Our study shows higher <span class="hlt">recurrence</span> <span class="hlt">rates</span> of CD after first TSS than previously reported. Second TSS leads an additional 8% of the patients to long-term CD remission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26386496','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26386496"><span>Reduction of <span class="hlt">recurrence</span> <span class="hlt">rate</span> of benign paroxysmal positional vertigo by treatment of severe vitamin D deficiency.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Talaat, Hossam Sanyelbhaa; Kabel, Abdel-Magied Hasan; Khaliel, Lobna Hamed; Abuhadied, Ghada; El-Naga, Heba Abd El-Rehem Abo; Talaat, Ahmed Sanyelbhaa</p> <p>2016-06-01</p> <p>Several studies correlated between vitamin D deficiency and the development, and the <span class="hlt">recurrence</span> of benign positional paroxysmal vertigo (BPPV), but none of them proved that treatment of vitamin D deficiency would reduce the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of BPPV. This study aims to detect the effect of treatment of severe vitamin D deficiency on the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of BPPV. The inclusion criteria of the study group were: (1) Unilateral, idiopathic, posterior canal BPPV with no history suggestive of secondary BPPV and (2) 25-hydroxyvitamin D3 level ≤10 ng/ml. All subjects enrolled in the current study underwent detailed clinical history, audiovestibular evaluation consisting of pure-tone audiometry, Immittancemetry, Videonystugmography, serum 25-hydroxyvitamin D3 assessment, and Dual-energy X-ray absorptiometry (DXA). Vitamin D therapy was prescribed for the study group. Serum 25-hydroxyvitamin D3 level was evaluated twice, on recruitment into the study group and 3 months after commencing vitamin D therapy. According to the results of the second evaluation of serum 25-hydroxyvitamin D3, the study group was subdivided into two subgroups: Subgroup (I): including 28 subjects who disclosed elevation of serum 25-hydroxyvitamin D3 level; improvement ≥10 ng/ml. Subgroup (II): including 65 patients who disclosed elevation of serum 25-hydroxyvitamin D3 levels <10 ng/ml. The study group was followed up for 18 months in order to observe the <span class="hlt">recurrence</span> of BPPV. The differences between both study subgroups (I) & (II) regarding age, sex distribution, and bone mineral density were insignificant. The number of subjects who had <span class="hlt">recurrence</span> of BPPV in subgroup (I) was 4 (14%) versus 28 subjects (43%) in subgroup (II). The mean values for <span class="hlt">recurrent</span> attacks/subject in subgroups (I) & (II) were 0.18, and 0.66 attack/subject respectively; these differences between both subgroups were of high statistical significance (p<0.01). The Odds Ratio for development of <span class="hlt">recurrence</span> of BPPV in subjects with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24883378','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24883378"><span>Detection of burst suppression patterns in EEG using <span class="hlt">recurrence</span> <span class="hlt">rate</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liang, Zhenhu; Wang, Yinghua; Ren, Yongshao; Li, Duan; Voss, Logan; Sleigh, Jamie; Li, Xiaoli</p> <p>2014-01-01</p> <p>Burst suppression is a unique electroencephalogram (EEG) pattern commonly seen in cases of severely reduced brain activity such as overdose of general anesthesia. It is important to detect burst suppression reliably during the administration of anesthetic or sedative agents, especially for cerebral-protective treatments in various neurosurgical diseases. This study investigates <span class="hlt">recurrent</span> plot (RP) analysis for the detection of the burst suppression pattern (BSP) in EEG. The RP analysis is applied to EEG data containing BSPs collected from 14 patients. Firstly we obtain the best selection of parameters for RP analysis. Then, the <span class="hlt">recurrence</span> <span class="hlt">rate</span> (RR), determinism (DET), and entropy (ENTR) are calculated. Then RR was selected as the best BSP index one-way analysis of variance (ANOVA) and multiple comparison tests. Finally, the performance of RR analysis is compared with spectral analysis, bispectral analysis, approximate entropy, and the nonlinear energy operator (NLEO). ANOVA and multiple comparison tests showed that the RR could detect BSP and that it was superior to other measures with the highest sensitivity of suppression detection (96.49%, P = 0.03). Tracking BSP patterns is essential for clinical monitoring in critically ill and anesthetized patients. The purposed RR may provide an effective burst suppression detector for developing new patient monitoring systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22494308-valuation-indonesian-catastrophic-earthquake-bonds-generalized-extreme-value-gev-distribution-cox-ingersoll-ross-cir-interest-rate-model','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22494308-valuation-indonesian-catastrophic-earthquake-bonds-generalized-extreme-value-gev-distribution-cox-ingersoll-ross-cir-interest-rate-model"><span>Valuation of Indonesian catastrophic <span class="hlt">earthquake</span> bonds with generalized extreme value (GEV) distribution and Cox-Ingersoll-Ross (CIR) interest <span class="hlt">rate</span> model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Gunardi,; Setiawan, Ezra Putranda</p> <p></p> <p>Indonesia is a country with high risk of <span class="hlt">earthquake</span>, because of its position in the border of earth’s tectonic plate. An <span class="hlt">earthquake</span> could raise very high amount of damage, loss, and other economic impacts. So, Indonesia needs a mechanism for transferring the risk of <span class="hlt">earthquake</span> from the government or the (reinsurance) company, as it could collect enough money for implementing the rehabilitation and reconstruction program. One of the mechanisms is by issuing catastrophe bond, ‘act-of-God bond’, or simply CAT bond. A catastrophe bond issued by a special-purpose-vehicle (SPV) company, and then sold to the investor. The revenue from this transactionmore » is joined with the money (premium) from the sponsor company and then invested in other product. If a catastrophe happened before the time-of-maturity, cash flow from the SPV to the investor will discounted or stopped, and the cash flow is paid to the sponsor company to compensate their loss because of this catastrophe event. When we consider the <span class="hlt">earthquake</span> only, the amount of discounted cash flow could determine based on the earthquake’s magnitude. A case study with Indonesian <span class="hlt">earthquake</span> magnitude data show that the probability of maximum magnitude can model by generalized extreme value (GEV) distribution. In pricing this catastrophe bond, we assumed stochastic interest <span class="hlt">rate</span> that following the Cox-Ingersoll-Ross (CIR) interest <span class="hlt">rate</span> model. We develop formulas for pricing three types of catastrophe bond, namely zero coupon bonds, ‘coupon only at risk’ bond, and ‘principal and coupon at risk’ bond. Relationship between price of the catastrophe bond and CIR model’s parameter, GEV’s parameter, percentage of coupon, and discounted cash flow rule then explained via Monte Carlo simulation.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28224817','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28224817"><span>Is the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of chronic subdural hematomas dependent on the duration of drainage?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kale, Aydemir; Öz, İbrahim İlker; Gün, Eren Görkem; Kalaycı, Murat; Gül, Şanser</p> <p>2017-05-01</p> <p>Chronic subdural hematoma (CSDH) is the most frequent type of intracranial hemorrhage which especially affects the elderly. Various surgical techniques have been reported for CSDH treatment; optimal treatment methods are still controversial. In this study, the effects of long drainage durations on results and <span class="hlt">recurrences</span> were investigated in patients on whom closed system drainage with burr hole craniotomy was applied due to CSDH. 90 patients with 105 CSDH were operated between 2008 and 2016. Patients were divided into two groups based on the duration of drainage. Group A (n = 40) was determined as 2-4 days of closed-system drainage, while Group B (n = 50) was recorded as 5-7 days of closed-system drainage. <span class="hlt">Recurrence</span> was defined as accumulation of blood in the operation area and <span class="hlt">recurrence</span> of symptoms within the monitoring period of six months. <span class="hlt">Recurrence</span> was observed in 7 (15.6) of the Group A patients and 2 (3.3%) of the Group B patients. There was a statistically significant difference between groups in terms of <span class="hlt">recurrence</span> <span class="hlt">rate</span> (p = 0.04). Postoperative thickness of hematoma was measured in the first month follow-up computerized tomography. There was a statistically significant difference between groups in terms of postoperative thickness of residual hematoma (p = 0.05). 2-4 days of closed system drainage following burr hole craniotomy is an effective and reliable choice of treatment in CSDH. Nevertheless, increasing the duration of drainage to 5-7 days provided better results without increasing the risk of complication.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11704950','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11704950"><span>Comparison of the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of gastric dilatation with or without volvulus in dogs after circumcostal gastropexy versus gastrocolopexy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eggertsdóttir, A V; Stigen y, Ø; Lønaas, L; Langeland, M; Devor, M; Vibe-Petersen, G; Eriksen, T</p> <p>2001-01-01</p> <p>To compare the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of acute gastric dilatation with or without volvulus (GDV) after circumcostal gastropexy (CCGP) or gastrocolopexy (GCP) in dogs. A prospective, double-blind, multicenter, randomized, controlled, clinical trial with two groups (A and B). Fifty-four client-owned dogs presented for treatment of GDV. Dogs with acute GDV that had not previously had a gastropexy performed were included. The preoperative treatment before gastropexy was standardized. A CCGP was performed on dogs in group A, and a GCP was performed on dogs in group B. Postoperative treatment was standardized, but deviation did occur according to the special needs of particular patients. A minimal follow-up time of 180 days was required for dogs not excluded from the study. The median follow-up time in group A was 700 days; in group B, it was 400 days. The occurrence of abdominal pain and gastrointestinal problems after surgery were recorded by the owners. There was no significant difference in the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of GDV between the two groups. At the end of the study, the <span class="hlt">recurrence</span> <span class="hlt">rate</span> was 9% and 20% in group A and in group B, respectively. Both surgical techniques are effective in preventing <span class="hlt">recurrence</span> of GDV. Copyright 2001 by The American College of Veterinary Surgeons</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2009/1136/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2009/1136/"><span>Estimating Casualties for Large <span class="hlt">Earthquakes</span> Worldwide Using an Empirical Approach</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jaiswal, Kishor; Wald, David J.; Hearne, Mike</p> <p>2009-01-01</p> <p>We developed an empirical country- and region-specific <span class="hlt">earthquake</span> vulnerability model to be used as a candidate for post-<span class="hlt">earthquake</span> fatality estimation by the U.S. Geological Survey's Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER) system. The <span class="hlt">earthquake</span> fatality <span class="hlt">rate</span> is based on past fatal <span class="hlt">earthquakes</span> (<span class="hlt">earthquakes</span> causing one or more deaths) in individual countries where at least four fatal <span class="hlt">earthquakes</span> occurred during the catalog period (since 1973). Because only a few dozen countries have experienced four or more fatal <span class="hlt">earthquakes</span> since 1973, we propose a new global regionalization scheme based on idealization of countries that are expected to have similar susceptibility to future <span class="hlt">earthquake</span> losses given the existing building stock, its vulnerability, and other socioeconomic characteristics. The fatality estimates obtained using an empirical country- or region-specific model will be used along with other selected engineering risk-based loss models for generation of automated <span class="hlt">earthquake</span> alerts. These alerts could potentially benefit the rapid-<span class="hlt">earthquake</span>-response agencies and governments for better response to reduce <span class="hlt">earthquake</span> fatalities. Fatality estimates are also useful to stimulate <span class="hlt">earthquake</span> preparedness planning and disaster mitigation. The proposed model has several advantages as compared with other candidate methods, and the country- or region-specific fatality <span class="hlt">rates</span> can be readily updated when new data become available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15326555','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15326555"><span>[Analysis of Foetal Heart <span class="hlt">Rate</span> Data using Complex Software: Comparison of <span class="hlt">Recurrence</span> Plot of Foetal Heart <span class="hlt">Rate</span> with the Course of Pregnancy -].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jörn, H; Morgenstern, B; Wassenberg, B; Rath, W</p> <p>2004-08-01</p> <p>Is it useful to further analyse foetal heart <span class="hlt">rate</span> to improve the prediction of pregnancy complications? The analysis of the foetal heart <span class="hlt">rate</span> is usually based on the variability of the heart <span class="hlt">rate</span>, i. e. the more variable the heart <span class="hlt">rate</span> presents - except a decrease - the better the condition of the foetus is. The same concept is applied in our own analysis which differs only in the presentation of the data. We analysed 25 non-stress-tests from unselected third trimester pregnancies using sophisticated software. The <span class="hlt">recurrence</span> plot (RP) is able to rearrange data from foetal heart <span class="hlt">rate</span> monitoring in order to make the heart <span class="hlt">rate</span> variability visible. We developed criteria for a normal and an abnormal test result describing the structure of the diagram to predict an uneventful and a high-risk pregnancy, respectively. 11 out of 11 patients with uneventful course and outcome of pregnancy showed a coarse and blurred RP pattern. 12 out of 14 (86 %) patients developing either intrauterine growth retardation or preeclampsia and requiring caesarean section because of foetal heart <span class="hlt">rate</span> abnormalities showed a fine and clear RP pattern. Our preliminary results show that it makes sense to further evaluate foetal heart <span class="hlt">rate</span> variability in order to predict pregnancy complications. Computer programs including the algorithms needed (calculation of the <span class="hlt">recurrence</span> plot) are not expensive and easy to handle. A widespread use of these programs represents the basis requirement for large controlled clinical trials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH13B..08A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH13B..08A"><span>Insights from interviews regarding high fatality <span class="hlt">rate</span> caused by the 2011 Tohoku-Oki <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ando, M.; Ishida, M.</p> <p>2012-12-01</p> <p>The 11 March 2011 Tohoku-Oki <span class="hlt">earthquake</span> (Mw9.0) caused approximately 19,000 casualties including missing persons along the entire coast of the Tohoku region. Three historical tsunamis occurred in the past 115 years preceding this tsunami. Since these tsunamis, numerous countermeasures against future tsunamis such as breakwaters, early tsunami warning systems and tsunami evacuation drills were implemented. Despite the preparedness, a number of deaths and missing persons occurred. Although this death <span class="hlt">rate</span> is approximately 4 % of the population in severely inundated areas; 96 % safely evacuated or managed to survive the tsunami. To understand why some people evacuated immediately while others delayed; survivors were interviewed in the northern part of the Tohoku region. Our interviews revealed that many residents obtained no appropriate warnings and many chose to remain in dangerous locations partly because they obtained the wrong idea of the risks. In addition, our interviews also indicated that the resultant high casualties were due to current technology malfunction, underestimated <span class="hlt">earthquake</span> size and tsunami heights, and failure of warning systems. Furthermore, the existing breakwaters provided the local community a false sense of security. The advanced technology did not work properly, especially at the time of the severe disaster. If residents had taken an immediate action after the major shaking stopped, most local residents might have survived considering that safer highlands are within 5 to 20 minute walking distance from the interviewed areas. However, the elderly and physically disabled people would still be in a much more difficult situation to walk such distance into safety. Nevertheless, even if these problems occur in future <span class="hlt">earthquakes</span>, better knowledge regarding <span class="hlt">earthquakes</span> and tsunami hazards could save more lives. People must take immediate action without waiting for official warning or help. To avoid similar high tsunami death ratios in the future</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24014082','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24014082"><span>HIV positivity but not HPV/p16 status is associated with higher <span class="hlt">recurrence</span> <span class="hlt">rate</span> in anal cancer.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Meyer, Joshua E; Panico, Vinicius J A; Marconato, Heloisa M F; Sherr, David L; Christos, Paul; Pirog, Edyta C</p> <p>2013-12-01</p> <p>Human papillomavirus (HPV) is a pathogenic factor of squamous cell carcinoma in various mucosal locations, including anal carcinoma (ACA). It is also known that patients positive for HIV are at high risk of ACA. The goal of this study was to examine clinical outcome in ACA in relation to HPV/p16 positivity, histologic tumor differentiation, and HIV status. Patients with oropharyngeal cancers that are positive for HPV and show overexpression of p16 as well as having non-keratinizing/basaloid histology have been reported to have better outcomes following chemoradiation (CRT). However, such relationships in ACA remain unknown. Forty-two patients with SCC of the anus treated with CRT between 1997 and 2009 were identified. The tumors were subclassified as either non-keratinizing (including basaloid) or keratinizing categories. HPV testing was performed using SPF10-PCR, and all cases were immunostained for p16. There were 23 men and 19 women; 43% of men and 11% of women were HIV-positive (p = 0.04). Fifty-five percent of patients had local disease (stages I and II) and 41% were stages III and IV, with 4% stage unknown. All tumors were positive for high-oncogenic risk HPVs, and all were positive with p16 immunostain. Sixty-four percent of tumors were non-keratinizing/basaloid and 36 % were keratinizing. The keratinizing tumors were more common in HIV-positive patients (67%), whereas non-keratinizing/basaloid tumors were more common in HIV-negative patients (77%) (p = 0.008). Thirty-one percent of patients had <span class="hlt">recurrence</span> of disease, including 50% HIV-positive patients and 23% HIV-negative patients (p = 0.09). There was no difference in the <span class="hlt">recurrence</span> <span class="hlt">rate</span> between non-keratinizing and keratinizing tumor subtypes (p = 0.80). The 24-month <span class="hlt">recurrence</span>-free survival for the cohort was 66% (95% CI = 46%, 81%), with HIV-positive patients having worse <span class="hlt">recurrence</span>-free survival compared to HIV-negative patients (HR = 2.85, 95% CI = 0.95, 8.53; p = 0</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.5707F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.5707F"><span>Time-Varying Upper-Plate Deformation during the Megathrust Subduction <span class="hlt">Earthquake</span> Cycle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Furlong, Kevin P.; Govers, Rob; Herman, Matthew</p> <p>2015-04-01</p> <p>Over the past several decades of the WEGENER era, our abilities to observe and image the deformational behavior of the upper plate in megathrust subduction zones has dramatically improved. Several intriguing inferences can be made from these observations including apparent lateral variations in locking along subduction zones, which differs from interseismic to coseismic periods; the significant magnitude of post-<span class="hlt">earthquake</span> deformation (e.g. following the 20U14 Mw Iquique, Chile <span class="hlt">earthquake</span>, observed on-land GPS post-EQ displacements are comparable to the co-seismic displacements); and incompatibilities between <span class="hlt">rates</span> of slip deficit accumulation and resulting <span class="hlt">earthquake</span> co-seismic slip (e.g. pre-Tohoku, inferred <span class="hlt">rates</span> of slip deficit accumulation on the megathrust significantly exceed slip amounts for the ~ 1000 year <span class="hlt">recurrence</span>.) Modeling capabilities have grown from fitting simple elastic accumulation/rebound curves to sparse data to having spatially dense continuous time series that allow us to infer details of plate boundary coupling, rheology-driven transient deformation, and partitioning among inter-<span class="hlt">earthquake</span> and co-seismic displacements. In this research we utilize a 2D numerical modeling to explore the time-varying deformational behavior of subduction zones during the <span class="hlt">earthquake</span> cycle with an emphasis on upper-plate and plate interface behavior. We have used a simplified model configuration to isolate fundamental processes associated with the <span class="hlt">earthquake</span> cycle, rather than attempting to fit details of specific megathrust zones. Using a simple subduction geometry, but realistic rheologic layering we are evaluating the time-varying displacement and stress response through a multi-<span class="hlt">earthquake</span> cycle history. We use a simple model configuration - an elastic subducting slab, an elastic upper plate (shallower than 40 km), and a visco-elastic upper plate (deeper than 40 km). This configuration leads to an upper plate that acts as a deforming elastic beam at inter-<span class="hlt">earthquake</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S51A2643D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S51A2643D"><span>Spatio-temporal Variations of Characteristic Repeating <span class="hlt">Earthquake</span> Sequences along the Middle America Trench in Mexico</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dominguez, L. A.; Taira, T.; Hjorleifsdottir, V.; Santoyo, M. A.</p> <p>2015-12-01</p> <p>Repeating <span class="hlt">earthquake</span> sequences are sets of events that are thought to rupture the same area on the plate interface and thus provide nearly identical waveforms. We systematically analyzed seismic records from 2001 through 2014 to identify repeating <span class="hlt">earthquakes</span> with highly correlated waveforms occurring along the subduction zone of the Cocos plate. Using the correlation coefficient (cc) and spectral coherency (coh) of the vertical components as selection criteria, we found a set of 214 sequences whose waveforms exceed cc≥95% and coh≥95%. Spatial clustering along the trench shows large variations in repeating <span class="hlt">earthquakes</span> activity. Particularly, the rupture zone of the M8.1, 1985 <span class="hlt">earthquake</span> shows an almost absence of characteristic repeating <span class="hlt">earthquakes</span>, whereas the Guerrero Gap zone and the segment of the trench close to the Guerrero-Oaxaca border shows a significantly larger number of repeating <span class="hlt">earthquakes</span> sequences. Furthermore, temporal variations associated to stress changes due to major shows episodes of unlocking and healing of the interface. Understanding the different components that control the location and <span class="hlt">recurrence</span> time of characteristic repeating sequences is a key factor to pinpoint areas where large megathrust <span class="hlt">earthquakes</span> may nucleate and consequently to improve the seismic hazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/sir/2017/5013/sir20175013ah_v1.1.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/sir/2017/5013/sir20175013ah_v1.1.pdf"><span>The HayWired <span class="hlt">Earthquake</span> Scenario—<span class="hlt">Earthquake</span> Hazards</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Detweiler, Shane T.; Wein, Anne M.</p> <p>2017-04-24</p> <p>The HayWired scenario is a hypothetical <span class="hlt">earthquake</span> sequence that is being used to better understand hazards for the San Francisco Bay region during and after an <span class="hlt">earthquake</span> of magnitude 7 on the Hayward Fault. The 2014 Working Group on California <span class="hlt">Earthquake</span> Probabilities calculated that there is a 33-percent likelihood of a large (magnitude 6.7 or greater) <span class="hlt">earthquake</span> occurring on the Hayward Fault within three decades. A large Hayward Fault <span class="hlt">earthquake</span> will produce strong ground shaking, permanent displacement of the Earth’s surface, landslides, liquefaction (soils becoming liquid-like during shaking), and subsequent fault slip, known as afterslip, and <span class="hlt">earthquakes</span>, known as aftershocks. The most recent large <span class="hlt">earthquake</span> on the Hayward Fault occurred on October 21, 1868, and it ruptured the southern part of the fault. The 1868 magnitude-6.8 <span class="hlt">earthquake</span> occurred when the San Francisco Bay region had far fewer people, buildings, and infrastructure (roads, communication lines, and utilities) than it does today, yet the strong ground shaking from the <span class="hlt">earthquake</span> still caused significant building damage and loss of life. The next large Hayward Fault <span class="hlt">earthquake</span> is anticipated to affect thousands of structures and disrupt the lives of millions of people. <span class="hlt">Earthquake</span> risk in the San Francisco Bay region has been greatly reduced as a result of previous concerted efforts; for example, tens of billions of dollars of investment in strengthening infrastructure was motivated in large part by the 1989 magnitude 6.9 Loma Prieta <span class="hlt">earthquake</span>. To build on efforts to reduce <span class="hlt">earthquake</span> risk in the San Francisco Bay region, the HayWired <span class="hlt">earthquake</span> scenario comprehensively examines the <span class="hlt">earthquake</span> hazards to help provide the crucial scientific information that the San Francisco Bay region can use to prepare for the next large <span class="hlt">earthquake</span>, The HayWired <span class="hlt">Earthquake</span> Scenario—<span class="hlt">Earthquake</span> Hazards volume describes the strong ground shaking modeled in the scenario and the hazardous movements of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25963974','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25963974"><span>Management of Bartholin's cyst and abscess using the Word catheter: implementation, <span class="hlt">recurrence</span> <span class="hlt">rates</span> and costs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Reif, Philipp; Ulrich, Daniela; Bjelic-Radisic, Vesna; Häusler, Martin; Schnedl-Lamprecht, Elke; Tamussino, Karl</p> <p>2015-07-01</p> <p>Bartholin's cysts and abscesses occur in about 2% of women. None of the surgical or conservative treatment approaches have been proven to be superior. The Word catheter is an outpatient treatment option, but little is known about aspects of implementing this therapy in an office setting. The present study's focus is on <span class="hlt">recurrence</span> <span class="hlt">rates</span> and organizational requirements of implementing outpatient treatment of Bartholin's cyst and abscess and compares costs of Word catheter treatment and marsupialization. Between March 2013 and May 2014 30 women were included in the study. We measured time consumed for treatment and follow-up and analyzed costs using the Word catheter and marsupialization under general anesthesia. We also assessed the ease of use of the Word catheter for application and removal using a standardized visual analog scale (VAS 1-10). Word catheter treatment was successful in 26/30 cases (87%). Balloon loss before the end of the 4-week treatment period occurred in 11/26 cases with a mean residence time of 19.1 (±10.0) days. None of the patients with early catheter loss developed <span class="hlt">recurrent</span> cyst or abscess. <span class="hlt">Recurrence</span> occurred in 1/26 cases (3.8%). Difficulty-score of application was 2 [1-10] and of removal 1 [1], respectively. Costs were € 216 for the treatment in the clinic as compared with € 1584/€ 1282 for surgical marsupialization with a one-night stay or daycare clinic, respectively. The present study indicates that the Word catheter is an easy to handle, low cost outpatient procedure with acceptable short-term <span class="hlt">recurrence</span> <span class="hlt">rates</span>. Treatment costs are seven times lower than for marsupialization. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S21E..08B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S21E..08B"><span>Moment Magnitudes and Local Magnitudes for Small <span class="hlt">Earthquakes</span>: Implications for Ground-Motion Prediction and b-values</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baltay, A.; Hanks, T. C.; Vernon, F.</p> <p>2016-12-01</p> <p>We illustrate two essential consequences of the systematic difference between moment magnitude and local magnitude for small <span class="hlt">earthquakes</span>, illuminating the underlying <span class="hlt">earthquake</span> physics. Moment magnitude, M 2/3 log M0, is uniformly valid for all <span class="hlt">earthquake</span> sizes [Hanks and Kanamori, 1979]. However, the relationship between local magnitude ML and moment is itself magnitude dependent. For moderate events, 3< M < 7, M and M­L are coincident; for <span class="hlt">earthquakes</span> smaller than M3, ML log M0 [Hanks and Boore, 1984]. This is a consequence of the saturation of the apparent corner frequency fc as it becoming greater than the largest observable frequency, fmax; In this regime, stress drop no longer controls ground motion. This implies that ML and M differ by a factor of 1.5 for these small events. While this idea is not new, its implications are important as more small-magnitude data are incorporated into <span class="hlt">earthquake</span> hazard research. With a large dataset of M<3 <span class="hlt">earthquakes</span> recorded on the ANZA network, we demonstrate striking consequences of the difference between M and ML. ML scales as the log peak ground motions (e.g., PGA or PGV) for these small <span class="hlt">earthquakes</span>, which yields log PGA log M0 [Boore, 1986]. We plot nearly 15,000 records of PGA and PGV at close stations, adjusted for site conditions and for geometrical spreading to 10 km. The slope of the log of ground motion is 1.0*ML­, or 1.5*M, confirming the relationship, and that fc >> fmax. Just as importantly, if this relation is overlooked, prediction of large-magnitude ground motion from small <span class="hlt">earthquakes</span> will be misguided. We also consider the effect of this magnitude scale difference on b-value. The oft-cited b-value of 1 should hold for small magnitudes, given M. Use of ML necessitates b=2/3 for the same data set; use of mixed, or unknown, magnitudes complicates the matter further. This is of particular import when estimating the <span class="hlt">rate</span> of large <span class="hlt">earthquakes</span> when one has limited data on their <span class="hlt">recurrence</span>, as is the case for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70014767','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70014767"><span>Failure of self-similarity for large (Mw > 81/4) <span class="hlt">earthquakes</span>.</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Hartzell, S.H.; Heaton, T.H.</p> <p>1988-01-01</p> <p>Compares teleseismic P-wave records for <span class="hlt">earthquakes</span> in the magnitude range from 6.0-9.5 with synthetics for a self-similar, omega 2 source model and conclude that the energy radiated by very large <span class="hlt">earthquakes</span> (Mw > 81/4) is not self-similar to that radiated from smaller <span class="hlt">earthquakes</span> (Mw < 81/4). Furthermore, in the period band from 2 sec to several tens of seconds, it is concluded that large subduction <span class="hlt">earthquakes</span> have an average spectral decay <span class="hlt">rate</span> of omega -1.5. This spectral decay <span class="hlt">rate</span> is consistent with a previously noted tendency of the omega 2 model to overestimate Ms for large <span class="hlt">earthquakes</span>.-Authors</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593482','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4593482"><span>Regression Analysis of Mixed <span class="hlt">Recurrent</span>-Event and Panel-Count Data with Additive <span class="hlt">Rate</span> Models</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhu, Liang; Zhao, Hui; Sun, Jianguo; Leisenring, Wendy; Robison, Leslie L.</p> <p>2015-01-01</p> <p>Summary Event-history studies of <span class="hlt">recurrent</span> events are often conducted in fields such as demography, epidemiology, medicine, and social sciences (Cook and Lawless, 2007; Zhao et al., 2011). For such analysis, two types of data have been extensively investigated: <span class="hlt">recurrent</span>-event data and panel-count data. However, in practice, one may face a third type of data, mixed <span class="hlt">recurrent</span>-event and panel-count data or mixed event-history data. Such data occur if some study subjects are monitored or observed continuously and thus provide <span class="hlt">recurrent</span>-event data, while the others are observed only at discrete times and hence give only panel-count data. A more general situation is that each subject is observed continuously over certain time periods but only at discrete times over other time periods. There exists little literature on the analysis of such mixed data except that published by Zhu et al. (2013). In this paper, we consider the regression analysis of mixed data using the additive <span class="hlt">rate</span> model and develop some estimating equation-based approaches to estimate the regression parameters of interest. Both finite sample and asymptotic properties of the resulting estimators are established, and the numerical studies suggest that the proposed methodology works well for practical situations. The approach is applied to a Childhood Cancer Survivor Study that motivated this study. PMID:25345405</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/10235348','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/10235348"><span>Laparoscopic preperitoneal repair of <span class="hlt">recurrent</span> inguinal hernias.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sayad, P; Ferzli, G</p> <p>1999-04-01</p> <p>Repair of <span class="hlt">recurrent</span> inguinal hernias using the conventional open technique has been associated with high <span class="hlt">rates</span> of <span class="hlt">recurrence</span> and complications. Stoppa has reported a low <span class="hlt">recurrence</span> <span class="hlt">rate</span> using the open preperitoneal approach. Evolution of laparoscopic techniques has allowed the reproduction of the open preperitoneal repair via an endoscopic totally extraperitoneal (TEP) approach. This study reviewed all the <span class="hlt">recurrent</span> inguinal hernias repaired laparoscopically and evaluated the complication and <span class="hlt">recurrence</span> <span class="hlt">rate</span>. A total of 512 inguinal hernias were treated laparoscopically using the TEP approach. Of these, 75 were <span class="hlt">recurrent</span>. The ages of the 61 men ranged from 36 to 65 years. There were 41 direct and 34 indirect hernias. Fourteen were bilateral. None of the repairs was converted to an open procedure. The operating time ranged from 20 to 145 min (median 42 min). All patients were discharged home on the same day. There were no deaths. The complications consisted of two instances of urinary retention and one groin collection. Patient follow-up ranged from 6 to 72 (median 40) months, and there have been no <span class="hlt">recurrences</span> to date. The TEP repair for <span class="hlt">recurrent</span> inguinal hernias can produce results comparable to the open preperitoneal technique with low morbidity and <span class="hlt">recurrence</span> <span class="hlt">rates</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27438419','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27438419"><span><span class="hlt">RECURRENCE</span> <span class="hlt">RATE</span> OF HELICOBACTER PYLORI IN PATIENTS WITH PEPTIC ULCER FIVE YEARS OR MORE AFTER SUCCESSFUL ERADICATION.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fernandes, Yuri Costa Farago; Bonatto, Gabriel da Rocha; Bonatto, Mauro Willeman</p> <p>2016-01-01</p> <p>Infection with Helicobacter pylori is highly prevalent worldwide, especially in developing countries. Its presence in the gastroduodenal mucosa is related with development of peptic ulcer and other illnesses. The eradication of H. pylori improves mucosal histology in patients with peptic ulcers. This study was aimed to verify if H. pylori <span class="hlt">recurrence</span> occurs five years or more after confirmed eradication in patients with peptic ulcer. Moreover, we sought to determine the <span class="hlt">recurrence</span> <span class="hlt">rate</span>. Retrospective and longitudinal, this study was based on a sample of 201 patients from western Paraná, Brazil. The patients were diagnosed with peptic ulcer disease, in the period of 1990-2000, and followed for five years or more after successful H. pylori eradication. Patients with early <span class="hlt">recurrence</span> - prior to five years after eradication - were excluded from the sample. During an average follow-up of 8 years, 180 patients (89.55%) remained negative, and 21 (10.45%) became positive for H. pylori infection. New ulcers appeared in two-thirds of the patients with H. pylori <span class="hlt">recurrence</span>. The <span class="hlt">recurrence</span> of H. pylori in patients with peptic ulcer can occur in the long-term - even if the infection had been successfully eradicated and the patients had remained free of <span class="hlt">recurrence</span> in the first years of follow-up.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S23A4489F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S23A4489F"><span>Quantifying the <span class="hlt">Earthquake</span> Clustering that Independent Sources with Stationary <span class="hlt">Rates</span> (as Included in Current Risk Models) Can Produce.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fitzenz, D. D.; Nyst, M.; Apel, E. V.; Muir-Wood, R.</p> <p>2014-12-01</p> <p>The recent Canterbury <span class="hlt">earthquake</span> sequence (CES) renewed public and academic awareness concerning the clustered nature of seismicity. Multiple event occurrence in short time and space intervals is reminiscent of aftershock sequences, but aftershock is a statistical definition, not a label one can give an <span class="hlt">earthquake</span> in real-time. Aftershocks are defined collectively as what creates the Omori event <span class="hlt">rate</span> decay after a large event or are defined as what is taken away as "dependent events" using a declustering method. It is noteworthy that depending on the declustering method used on the Canterbury <span class="hlt">earthquake</span> sequence, the number of independent events varies a lot. This lack of unambiguous definition of aftershocks leads to the need to investigate the amount of clustering inherent in "declustered" risk models. This is the task we concentrate on in this contribution. We start from a background source model for the Canterbury region, in which 1) centroids of events of given magnitude are distributed using a latin-hypercube lattice, 2) following the range of preferential orientations determined from stress maps and focal mechanism, 3) with length determined using the local scaling relationship and 4) <span class="hlt">rates</span> from a and b values derived from the declustered pre-2010 catalog. We then proceed to create tens of thousands of realizations of 6 to 20 year periods, and we define criteria to identify which successions of events in the region would be perceived as a sequence. Note that the spatial clustering expected is a lower end compared to a fully uniform distribution of events. Then we perform the same exercise with <span class="hlt">rates</span> and b-values determined from the catalog including the CES. If the pre-2010 catalog was long (or rich) enough, then the computed "stationary" <span class="hlt">rates</span> calculated from it would include the CES declustered events (by construction, regardless of the physical meaning of or relationship between those events). In regions of low seismicity <span class="hlt">rate</span> (e.g., Canterbury before</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036562','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036562"><span>Uniform California <span class="hlt">earthquake</span> rupture forecast, version 2 (UCERF 2)</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Field, E.H.; Dawson, T.E.; Felzer, K.R.; Frankel, A.D.; Gupta, V.; Jordan, T.H.; Parsons, T.; Petersen, M.D.; Stein, R.S.; Weldon, R.J.; Wills, C.J.</p> <p>2009-01-01</p> <p>The 2007 Working Group on California <span class="hlt">Earthquake</span> Probabilities (WGCEP, 2007) presents the Uniform California <span class="hlt">Earthquake</span> Rupture Forecast, Version 2 (UCERF 2). This model comprises a time-independent (Poisson-process) <span class="hlt">earthquake</span> <span class="hlt">rate</span> model, developed jointly with the National Seismic Hazard Mapping Program and a time-dependent <span class="hlt">earthquake</span>-probability model, based on recent <span class="hlt">earthquake</span> <span class="hlt">rates</span> and stress-renewal statistics conditioned on the date of last event. The models were developed from updated statewide <span class="hlt">earthquake</span> catalogs and fault deformation databases using a uniform methodology across all regions and implemented in the modular, extensible Open Seismic Hazard Analysis framework. The <span class="hlt">rate</span> model satisfies integrating measures of deformation across the plate-boundary zone and is consistent with historical seismicity data. An overprediction of <span class="hlt">earthquake</span> <span class="hlt">rates</span> found at intermediate magnitudes (6.5 ??? M ???7.0) in previous models has been reduced to within the 95% confidence bounds of the historical <span class="hlt">earthquake</span> catalog. A logic tree with 480 branches represents the epistemic uncertainties of the full time-dependent model. The mean UCERF 2 time-dependent probability of one or more M ???6.7 <span class="hlt">earthquakes</span> in the California region during the next 30 yr is 99.7%; this probability decreases to 46% for M ???7.5 and to 4.5% for M ???8.0. These probabilities do not include the Cascadia subduction zone, largely north of California, for which the estimated 30 yr, M ???8.0 time-dependent probability is 10%. The M ???6.7 probabilities on major strike-slip faults are consistent with the WGCEP (2003) study in the San Francisco Bay Area and the WGCEP (1995) study in southern California, except for significantly lower estimates along the San Jacinto and Elsinore faults, owing to provisions for larger multisegment ruptures. Important model limitations are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204.1863P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204.1863P"><span>On the efficient and reliable numerical solution of <span class="hlt">rate</span>-and-state friction problems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pipping, Elias; Kornhuber, Ralf; Rosenau, Matthias; Oncken, Onno</p> <p>2016-03-01</p> <p>We present a mathematically consistent numerical algorithm for the simulation of <span class="hlt">earthquake</span> rupture with <span class="hlt">rate</span>-and-state friction. Its main features are adaptive time stepping, a novel algebraic solution algorithm involving nonlinear multigrid and a fixed point iteration for the <span class="hlt">rate</span>-and-state decoupling. The algorithm is applied to a laboratory scale subduction zone which allows us to compare our simulations with experimental results. Using physical parameters from the experiment, we find a good fit of <span class="hlt">recurrence</span> time of slip events as well as their rupture width and peak slip. Computations in 3-D confirm efficiency and robustness of our algorithm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70044369','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70044369"><span>Holocene behavior of the Brigham City segment: implications for forecasting the next large-magnitude <span class="hlt">earthquake</span> on the Wasatch fault zone, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Personius, Stephen F.; DuRoss, Christopher B.; Crone, Anthony J.</p> <p>2012-01-01</p> <p>The Brigham City segment (BCS), the northernmost Holocene‐active segment of the Wasatch fault zone (WFZ), is considered a likely location for the next big <span class="hlt">earthquake</span> in northern Utah. We refine the timing of the last four surface‐rupturing (~Mw 7) <span class="hlt">earthquakes</span> at several sites near Brigham City (BE1, 2430±250; BE2, 3490±180; BE3, 4510±530; and BE4, 5610±650 cal yr B.P.) and calculate mean <span class="hlt">recurrence</span> intervals (1060–1500  yr) that are greatly exceeded by the elapsed time (~2500  yr) since the most recent surface‐rupturing <span class="hlt">earthquake</span> (MRE). An additional rupture observed at the Pearsons Canyon site (PC1, 1240±50 cal yr B.P.) near the southern segment boundary is probably spillover rupture from a large <span class="hlt">earthquake</span> on the adjacent Weber segment. Our seismic moment calculations show that the PC1 rupture reduced accumulated moment on the BCS about 22%, a value that may have been enough to postpone the next large <span class="hlt">earthquake</span>. However, our calculations suggest that the segment currently has accumulated more than twice the moment accumulated in the three previous <span class="hlt">earthquake</span> cycles, so we suspect that additional interactions with the adjacent Weber segment contributed to the long elapse time since the MRE on the BCS. Our moment calculations indicate that the next <span class="hlt">earthquake</span> is not only overdue, but could be larger than the previous four <span class="hlt">earthquakes</span>. Displacement data show higher <span class="hlt">rates</span> of latest Quaternary slip (~1.3  mm/yr) along the southern two‐thirds of the segment. The northern third likely has experienced fewer or smaller ruptures, which suggests to us that most <span class="hlt">earthquakes</span> initiate at the southern segment boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.S51A1399C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.S51A1399C"><span>Time-dependent <span class="hlt">earthquake</span> forecasting: Method and application to the Italian region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chan, C.; Sorensen, M. B.; Grünthal, G.; Hakimhashemi, A.; Heidbach, O.; Stromeyer, D.; Bosse, C.</p> <p>2009-12-01</p> <p>We develop a new approach for time-dependent <span class="hlt">earthquake</span> forecasting and apply it to the Italian region. In our approach, the seismicity density is represented by a bandwidth function as a smoothing Kernel in the neighboring region of <span class="hlt">earthquakes</span>. To consider the fault-interaction-based forecasting, we calculate the Coulomb stress change imparted by each <span class="hlt">earthquake</span> in the study area. From this, the change of seismicity <span class="hlt">rate</span> as a function of time can be estimated by the concept of <span class="hlt">rate</span>-and-state stress transfer. We apply our approach to the region of Italy and <span class="hlt">earthquakes</span> that occurred before 2003 to generate the seismicity density. To validate our approach, we compare our estimated seismicity density with the distribution of <span class="hlt">earthquakes</span> with M≥3.8 after 2004. A positive correlation is found and all of the examined <span class="hlt">earthquakes</span> locate in the area of the highest 66 percentile of seismicity density in the study region. Furthermore, the seismicity density corresponding to the epicenter of the 2009 April 6, Mw = 6.3, L’Aquila <span class="hlt">earthquake</span> is in the area of the highest 5 percentile. For the time-dependent seismicity <span class="hlt">rate</span> change, we estimate the <span class="hlt">rate</span>-and-state stress transfer imparted by the M≥5.0 <span class="hlt">earthquakes</span> occurred in the past 50 years. It suggests that the seismicity <span class="hlt">rate</span> has increased at the locations of 65% of the examined <span class="hlt">earthquakes</span>. Applying this approach to the L’Aquila sequence by considering seven M≥5.0 aftershocks as well as the main shock, not only spatial but also temporal forecasting of the aftershock distribution is significant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26453404','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26453404"><span>Firing <span class="hlt">rate</span> dynamics in <span class="hlt">recurrent</span> spiking neural networks with intrinsic and network heterogeneity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ly, Cheng</p> <p>2015-12-01</p> <p>Heterogeneity of neural attributes has recently gained a lot of attention and is increasing recognized as a crucial feature in neural processing. Despite its importance, this physiological feature has traditionally been neglected in theoretical studies of cortical neural networks. Thus, there is still a lot unknown about the consequences of cellular and circuit heterogeneity in spiking neural networks. In particular, combining network or synaptic heterogeneity and intrinsic heterogeneity has yet to be considered systematically despite the fact that both are known to exist and likely have significant roles in neural network dynamics. In a canonical <span class="hlt">recurrent</span> spiking neural network model, we study how these two forms of heterogeneity lead to different distributions of excitatory firing <span class="hlt">rates</span>. To analytically characterize how these types of heterogeneities affect the network, we employ a dimension reduction method that relies on a combination of Monte Carlo simulations and probability density function equations. We find that the relationship between intrinsic and network heterogeneity has a strong effect on the overall level of heterogeneity of the firing <span class="hlt">rates</span>. Specifically, this relationship can lead to amplification or attenuation of firing <span class="hlt">rate</span> heterogeneity, and these effects depend on whether the <span class="hlt">recurrent</span> network is firing asynchronously or rhythmically firing. These observations are captured with the aforementioned reduction method, and furthermore simpler analytic descriptions based on this dimension reduction method are developed. The final analytic descriptions provide compact and descriptive formulas for how the relationship between intrinsic and network heterogeneity determines the firing <span class="hlt">rate</span> heterogeneity dynamics in various settings.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29788491','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29788491"><span>Lowering the <span class="hlt">recurrence</span> <span class="hlt">rate</span> in pigmented villonodular synovitis: A series of 120 resections.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Capellen, Carl Ferdinand; Tiling, Reinhold; Klein, Alexander; Baur-Melnyk, Andrea; Knösel, Thomas; Birkenmaier, Christof; Roeder, Falk; Jansson, Volkmar; Dürr, Hans Roland</p> <p>2018-05-16</p> <p>Tenosynovial giant-cell tumour or pigmented villonodular synovitis is an aggressive synovial proliferative disease, with the knee joint being the most commonly affected joint. The mainstay of therapy is surgical resection. The aim of this study was to evaluate the main patient characteristics, treatment and outcomes in a large single-centre retrospective study, focusing on meticulous aggressive open surgical procedures. From 1996 through 2014, 122 surgical interventions were performed in 105 patients. All patients underwent open synovectomy and when the knee joint was affected, combined anterior and posterior synovectomy. Radiotherapy was applied in 2 patients, radiosynoviorthesis in 27 patients. In histopathology, the diffuse type was seen in 66 (54%) lesions. Two patients were lost during follow-up. At a median follow-up time of 71 months (range: 13-238), 22 (18%) lesions recurred within a median of 18 months, >90% in the first 3 years. Out of those 22 <span class="hlt">recurrences</span>, 9 (11%) were seen in primary disease and 13 (34%) were a second <span class="hlt">recurrence</span>. After renewed resection, 6 (5%) out of the 120 resections had persistent tumour at the end of follow-up. Based on the number of patients with complete follow-up (n = 103), this represents 5.8%. In diffuse-type pigmented villonodular synovitis, total synovectomy might be difficult to achieve. As shown in our results and also in the literature, meticulous open resection, especially in difficult to approach areas such as the popliteal space, reduces local <span class="hlt">recurrence</span> <span class="hlt">rates</span>. External beam radiation is an option in prevention of otherwise non-operable local <span class="hlt">recurrences</span> or in non-operable disease.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGP41A1095F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGP41A1095F"><span>Magnetically Derived Flood <span class="hlt">Recurrence</span> <span class="hlt">Rate</span> Estimates from Stalagmites in Southeastern Minnesota</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feinberg, J. M.; Lascu, I.; Andrade Lima, E.; Weiss, B. P.</p> <p>2012-12-01</p> <p>The magnetism of speleothems remains an untapped resource of paleoclimatic, hydrogeologic, and geomagnetic information. Similar to other deposits containing magnetic minerals, speleothems chronicle the evolution of local environmental parameters via the concentration, composition and grain size of their magnetic mineral assemblages. Here we report a novel use of scanning SQUID microscopy to calculate flood <span class="hlt">recurrence</span> <span class="hlt">rates</span> from an annually laminated ~500 year old stalagmite from Spring Valley Caverns (SVC) in southeastern Minnesota. Mineral and organic detritus adheres to the surface of a speleothem as flood waters recede from a cavern, and are subsequently encapsulated by calcite as drip water conditions are reestablished. Such detritus typically consists of allochthonous grains of quartz, clay, and titanomagnetite with an average grain size of ~10 μm. Larger flood layers occur on polished surfaces as dark bands that delineate stalagmite growth horizons. We use scanning SQUID microscopy (with a nominal sensitivity of 10-16 Am2) to map the presence of these flood layers by measuring the vertical component of the stray magnetic field resulting from a 1 T isothermal remanent magnetization (IRM) imparted perpendicular to a polished surface. A magnetization model of the IRM field was then obtained by inverting the field data measured 210 μm above the sample using an algorithm in the Fourier domain. By integrating the magnetic data parallel to the stalagmite growth axis we produce a time series of IRM peaks, each of which corresponds to a flooding event. We calculate an average flood <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 5 per century for the last 500 years. This <span class="hlt">rate</span> increases to >10 floods per century in the last century, thereby capturing the combined effects of both climate change and agricultural land-use on karst hydrogeology. These results agree with <span class="hlt">recurrence</span> <span class="hlt">rate</span> estimates derived from historical records, tree ring studies, and geochemical analyses of speleothems. The presence</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S53D..05H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S53D..05H"><span>Viscoelastic <span class="hlt">Earthquake</span> Cycle Simulation with Memory Variable Method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hirahara, K.; Ohtani, M.</p> <p>2017-12-01</p> <p>There have so far been no EQ (<span class="hlt">earthquake</span>) cycle simulations, based on RSF (<span class="hlt">rate</span> and state friction) laws, in viscoelastic media, except for Kato (2002), who simulated cycles on a 2-D vertical strike-slip fault, and showed nearly the same cycles as those in elastic cases. The viscoelasticity could, however, give more effects on large dip-slip EQ cycles. In a boundary element approach, stress is calculated using a hereditary integral of stress relaxation function and slip deficit <span class="hlt">rate</span>, where we need the past slip <span class="hlt">rates</span>, leading to huge computational costs. This is a cause for almost no simulations in viscoelastic media. We have investigated the memory variable method utilized in numerical computation of wave propagation in dissipative media (e.g., Moczo and Kristek, 2005). In this method, introducing memory variables satisfying 1st order differential equations, we need no hereditary integrals in stress calculation and the computational costs are the same order of those in elastic cases. Further, Hirahara et al. (2012) developed the iterative memory variable method, referring to Taylor et al. (1970), in EQ cycle simulations in linear viscoelastic media. In this presentation, first, we introduce our method in EQ cycle simulations and show the effect of the linear viscoelasticity on stick-slip cycles in a 1-DOF block-SLS (standard linear solid) model, where the elastic spring of the traditional block-spring model is replaced by SLS element and we pull, in a constant <span class="hlt">rate</span>, the block obeying RSF law. In this model, the memory variable stands for the displacement of the dash-pot in SLS element. The use of smaller viscosity reduces the <span class="hlt">recurrence</span> time to a minimum value. The smaller viscosity means the smaller relaxation time, which makes the stress recovery quicker, leading to the smaller <span class="hlt">recurrence</span> time. Second, we show EQ cycles on a 2-D dip-slip fault with the dip angel of 20 degrees in an elastic layer with thickness of 40 km overriding a Maxwell viscoelastic half</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26643242','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26643242"><span>A contrast study of the traumatic condition between the wounded in 5.12 Wenchuan <span class="hlt">earthquake</span> and 4.25 Nepal <span class="hlt">earthquake</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ding, Sheng; Hu, Yonghe; Zhang, Zhongkui; Wang, Ting</p> <p>2015-01-01</p> <p>5.12 Wenchuan <span class="hlt">earthquake</span> and 4.25 Nepal <span class="hlt">earthquake</span> are of the similar magnitude, but the climate and geographic environment are totally different. Our team carried out medical rescue in both disasters, so we would like to compare the different traumatic conditions of the wounded in two <span class="hlt">earthquakes</span>. The clinical data of the wounded respectively in 5.12 Wenchuan <span class="hlt">earthquake</span> and 4.25 Nepal <span class="hlt">earthquake</span> rescued by Chengdu Military General Hospital were retrospectively analyzed. Then a contrast study between the wounded was conducted in terms of age, sex, injury mechanisms, traumatic conditions, complications and prognosis. Three days after 5.12 Wenchuan <span class="hlt">earthquake</span>, 465 cases of the wounded were hospitalized in Chengdu Military General Hospital, including 245 males (52.7%) and 220 females (47.3%) with the average age of (47.6±22.7) years. Our team carried out humanitarian relief in Katmandu after 4.25 Nepal <span class="hlt">earthquake</span>. Three days after this disaster, 71 cases were treated in our field hospital, including 37 males (52.1%) and 34 females (47.9%) with the mean age of (44.8±22.9) years. There was no obvious difference in sex and mean age between two groups, but the age distribution was a little different: there were more wounded people at the age over 60 years in 4.25 Nepal <span class="hlt">earthquake</span> (p<0.01) while more wounded people at the age between 21 and 60 years in 5.12 Wenchuan <span class="hlt">earthquake</span> (p<0.05). The main cause of injury in both disasters was bruise by heavy drops but 5.12 Wenchuan <span class="hlt">earthquake</span> had a higher <span class="hlt">rate</span> of bruise injury and crush injury (p<0.05) while 4.25 Nepal <span class="hlt">earthquake</span> had a higher <span class="hlt">rate</span> of falling injury (p<0.01). Limb fracture was the most common injury type in both disasters. However, compared with 5.12 Wenchuan <span class="hlt">earthquake</span>, 4.25 Nepal <span class="hlt">earthquake</span> has a much higher incidence of limb fractures (p<0.01), lung infection (p<0.01) and malnutrition (p<0.05), but a lower incidence of thoracic injury (p<0.05) and multiple injury (p<0.05). The other complications and death <span class="hlt">rate</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRB..11710303W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRB..11710303W"><span>Coseismic slip on the southern Cascadia megathrust implied by tsunami deposits in an Oregon lake and <span class="hlt">earthquake</span>-triggered marine turbidites</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Witter, Robert C.; Zhang, Yinglong; Wang, Kelin; Goldfinger, Chris; Priest, George R.; Allan, Jonathan C.</p> <p>2012-10-01</p> <p>We test hypothetical tsunami scenarios against a 4,600-year record of sandy deposits in a southern Oregon coastal lake that offer minimum inundation limits for prehistoric Cascadia tsunamis. Tsunami simulations constrain coseismic slip estimates for the southern Cascadia megathrust and contrast with slip deficits implied by <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals from turbidite paleoseismology. We model the tsunamigenic seafloor deformation using a three-dimensional elastic dislocation model and test three Cascadia <span class="hlt">earthquake</span> rupture scenarios: slip partitioned to a splay fault; slip distributed symmetrically on the megathrust; and slip skewed seaward. Numerical tsunami simulations use the hydrodynamic finite element model, SELFE, that solves nonlinear shallow-water wave equations on unstructured grids. Our simulations of the 1700 Cascadia tsunami require >12-13 m of peak slip on the southern Cascadia megathrust offshore southern Oregon. The simulations account for tidal and shoreline variability and must crest the ˜6-m-high lake outlet to satisfy geological evidence of inundation. Accumulating this slip deficit requires ≥360-400 years at the plate convergence <span class="hlt">rate</span>, exceeding the 330-year span of two <span class="hlt">earthquake</span> cycles preceding 1700. Predecessors of the 1700 <span class="hlt">earthquake</span> likely involved >8-9 m of coseismic slip accrued over >260 years. Simple slip budgets constrained by tsunami simulations allow an average of 5.2 m of slip per event for 11 additional <span class="hlt">earthquakes</span> inferred from the southern Cascadia turbidite record. By comparison, slip deficits inferred from time intervals separating <span class="hlt">earthquake</span>-triggered turbidites are poor predictors of coseismic slip because they meet geological constraints for only 4 out of 12 (˜33%) Cascadia tsunamis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S41C..08C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S41C..08C"><span>Tectonic tremor activity associated with teleseismic and nearby <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chao, K.; Obara, K.; Peng, Z.; Pu, H. C.; Frank, W.; Prieto, G. A.; Wech, A.; Hsu, Y. J.; Yu, C.; Van der Lee, S.; Apley, D. W.</p> <p>2016-12-01</p> <p>Tectonic tremor is an extremely stress-sensitive seismic phenomenon located in the brittle-ductile transition section of a fault. To better understand the stress interaction between tremor and <span class="hlt">earthquake</span>, we conduct the following studies: (1) search for triggered tremor globally, (2) examine ambient tremor activities associated with distant <span class="hlt">earthquakes</span>, and (3) quantify the temporal variation of ambient tremor activity before and after nearby <span class="hlt">earthquakes</span>. First, we developed a Matlab toolbox to enhance the searching of triggered tremor globally. We have discovered new tremor sources in the inland faults in Kyushu, Kanto, and Hokkaido in Japan, southern Chile, Ecuador, and central Colombia in South America, and in South Italy. Our findings suggest that tremor is more common than previously believed and indicate the potential existence of ambient tremor in the triggered tremor active regions. Second, we adapt the statistical analysis to examine whether the long-term ambient tremor <span class="hlt">rate</span> may affect by the dynamic stress of teleseismic <span class="hlt">earthquakes</span>. We analyzed the data in Nankai, Hokkaido, Cascadia, and Taiwan. Our preliminary results did not show an apparent increase of ambient tremor <span class="hlt">rate</span> after the passing of surface waves. Third, we quantify temporal changes in ambient tremor activity before and after the occurrence of local <span class="hlt">earthquakes</span> under the southern Central Range of Taiwan with magnitudes of >=5.5 from 2004 to 2016. For a particular case, we found a temporal variation of tremor <span class="hlt">rate</span> before and after the 2010/03/04 Mw6.3 <span class="hlt">earthquake</span>, located about 20 km away from the active tremor source. The long-term increase in the tremor <span class="hlt">rate</span> after the <span class="hlt">earthquake</span> could have been caused by an increase in static stress following the mainshock. For comparison, clear evidence from seismic and GPS observations indicate a short-term increase in the tremor <span class="hlt">rate</span> a few weeks before the mainshock. The increase in the tremor <span class="hlt">rate</span> before the mainshock could correlate with stress changes</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70018695','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70018695"><span>Holocene paleoseismicity, temporal clustering, and probabilities of future large (M > 7) <span class="hlt">earthquakes</span> on the Wasatch fault zone, Utah</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McCalpin, J.P.; Nishenko, S.P.</p> <p>1996-01-01</p> <p>The chronology of M>7 paleoearthquakes on the central five segments of the Wasatch fault zone (WFZ) is one of the best dated in the world and contains 16 <span class="hlt">earthquakes</span> in the past 5600 years with an average repeat time of 350 years. Repeat times for individual segments vary by a factor of 2, and range from about 1200 to 2600 years. Four of the central five segments ruptured between ??? 620??30 and 1230??60 calendar years B.P. The remaining segment (Brigham City segment) has not ruptured in the past 2120??100 years. Comparison of the WFZ space-time diagram of paleoearthquakes with synthetic paleoseismic histories indicates that the observed temporal clusters and gaps have about an equal probability (depending on model assumptions) of reflecting random coincidence as opposed to intersegment contagion. Regional seismicity suggests that for exposure times of 50 and 100 years, the probability for an <span class="hlt">earthquake</span> of M>7 anywhere within the Wasatch Front region, based on a Poisson model, is 0.16 and 0.30, respectively. A fault-specific WFZ model predicts 50 and 100 year probabilities for a M>7 <span class="hlt">earthquake</span> on the WFZ itself, based on a Poisson model, as 0.13 and 0.25, respectively. In contrast, segment-specific <span class="hlt">earthquake</span> probabilities that assume quasi-periodic <span class="hlt">recurrence</span> behavior on the Weber, Provo, and Nephi segments are less (0.01-0.07 in 100 years) than the regional or fault-specific estimates (0.25-0.30 in 100 years), due to the short elapsed times compared to average <span class="hlt">recurrence</span> intervals on those segments. The Brigham City and Salt Lake City segments, however, have time-dependent probabilities that approach or exceed the regional and fault specific probabilities. For the Salt Lake City segment, these elevated probabilities are due to the elapsed time being approximately equal to the average late Holocene <span class="hlt">recurrence</span> time. For the Brigham City segment, the elapsed time is significantly longer than the segment-specific late Holocene <span class="hlt">recurrence</span> time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S21B0700L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S21B0700L"><span>Comparison of aftershock sequences between 1975 Haicheng <span class="hlt">earthquake</span> and 1976 Tangshan <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, B.</p> <p>2017-12-01</p> <p>The 1975 ML 7.3 Haicheng <span class="hlt">earthquake</span> and the 1976 ML 7.8 Tangshan <span class="hlt">earthquake</span> occurred in the same tectonic unit. There are significant differences in spatial-temporal distribution, number of aftershocks and time duration for the aftershock sequence followed by these two main shocks. As we all know, aftershocks could be triggered by the regional seismicity change derived from the main shock, which was caused by the Coulomb stress perturbation. Based on the <span class="hlt">rate</span>- and state- dependent friction law, we quantitative estimated the possible aftershock time duration with a combination of seismicity data, and compared the results from different approaches. The results indicate that, aftershock time durations from the Tangshan main shock is several times of that form the Haicheng main shock. This can be explained by the significant relationship between aftershock time duration and <span class="hlt">earthquake</span> nucleation history, normal stressand shear stress loading rateon the fault. In fact the obvious difference of <span class="hlt">earthquake</span> nucleation history from these two main shocks is the foreshocks. 1975 Haicheng <span class="hlt">earthquake</span> has clear and long foreshocks, while 1976 Tangshan <span class="hlt">earthquake</span> did not have clear foreshocks. In that case, abundant foreshocks may mean a long and active nucleation process that may have changed (weakened) the rocks in the source regions, so they should have a shorter aftershock sequences for the reason that stress in weak rocks decay faster.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/biblio/22370536-shortest-recurrence-periods-novae','SCIGOV-STC'); return false;" href="https://www.osti.gov/biblio/22370536-shortest-recurrence-periods-novae"><span>Shortest <span class="hlt">recurrence</span> periods of novae</span></a></p> <p><a target="_blank" href="http://www.osti.gov/search">DOE Office of Scientific and Technical Information (OSTI.GOV)</a></p> <p>Kato, Mariko; Saio, Hideyuki; Hachisu, Izumi</p> <p></p> <p>Stimulated by the recent discovery of the 1 yr <span class="hlt">recurrence</span> period nova M31N 2008-12a, we examined the shortest <span class="hlt">recurrence</span> periods of hydrogen shell flashes on mass-accreting white dwarfs (WDs). We discuss the mechanism that yields a finite minimum <span class="hlt">recurrence</span> period for a given WD mass. Calculating the unstable flashes for various WD masses and mass accretion <span class="hlt">rates</span>, we identified a shortest <span class="hlt">recurrence</span> period of about two months for a non-rotating 1.38 M {sub ☉} WD with a mass accretion <span class="hlt">rate</span> of 3.6 × 10{sup –7} M {sub ☉} yr{sup –1}. A 1 yr <span class="hlt">recurrence</span> period is realized for very massivemore » (≳ 1.3 M {sub ☉}) WDs with very high accretion <span class="hlt">rates</span> (≳ 1.5 × 10{sup –7} M {sub ☉} yr{sup –1}). We revised our stability limit of hydrogen shell burning, which will be useful for binary evolution calculations toward Type Ia supernovae.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70026994','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70026994"><span>Comparing the November 2002 Denali and November 2001 Kunlun <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Bufe, C.G.</p> <p>2004-01-01</p> <p>Major strike-slip <span class="hlt">earthquakes</span> recently occurred in Alaska on the central Denali fault (M 7.9) on 3 November 2002, and in Tibet on the central Kunlun fault (M 7.8) on 14 November 2001. Both <span class="hlt">earthquakes</span> generated large surface waves with Ms [U.S. Geological Survey (USGS)] of 8.5 (Denali) and 8.0 (Kunlun). Each event occurred on an east-west-trending strike-slip fault situated near the northern boundary of an intense deformation zone that is characterized by lateral extrusion and rotation of crustal blocks. Each <span class="hlt">earthquake</span> produced east-directed nearly unilateral ruptures that propagated 300 to 400 km. Maximum lateral surface offsets and maximum moment release occurred well beyond 100 km from the rupture initiation, with the events exhibiting by far the largest separations of USGS hypocenter and Harvard Moment Tensor Centroid (CMT) for strike-slip <span class="hlt">earthquakes</span> in the 27-year CMT catalog. In each sequence, the largest aftershock was more than two orders of magnitude smaller than the mainshock. Regional moment release had been accelerating prior to the main shocks. The close proximity in space and time of the 1964 Prince William Sound and 2002 Denali <span class="hlt">earthquakes</span>, relative to their rupture lengths and estimated return times, suggests that these events may be part of a <span class="hlt">recurrent</span> cluster in the vicinity of a complex plate boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ready.gov/earthquakes','NIH-MEDLINEPLUS'); return false;" href="https://www.ready.gov/earthquakes"><span><span class="hlt">Earthquakes</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... Search Term(s): Main Content Home Be Informed <span class="hlt">Earthquakes</span> <span class="hlt">Earthquakes</span> An <span class="hlt">earthquake</span> is the sudden, rapid shaking of the earth, ... by the breaking and shifting of underground rock. <span class="hlt">Earthquakes</span> can cause buildings to collapse and cause heavy ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T13A2662B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T13A2662B"><span>How fault geometry controls <span class="hlt">earthquake</span> magnitude</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bletery, Q.; Thomas, A.; Karlstrom, L.; Rempel, A. W.; Sladen, A.; De Barros, L.</p> <p>2016-12-01</p> <p>Recent large megathrust <span class="hlt">earthquakes</span>, such as the Mw9.3 Sumatra-Andaman <span class="hlt">earthquake</span> in 2004 and the Mw9.0 Tohoku-Oki <span class="hlt">earthquake</span> in 2011, astonished the scientific community. The first event occurred in a relatively low-convergence-<span class="hlt">rate</span> subduction zone where events of its size were unexpected. The second event involved 60 m of shallow slip in a region thought to be aseismicaly creeping and hence incapable of hosting very large magnitude <span class="hlt">earthquakes</span>. These <span class="hlt">earthquakes</span> highlight gaps in our understanding of mega-<span class="hlt">earthquake</span> rupture processes and the factors controlling their global distribution. Here we show that gradients in dip angle exert a primary control on mega-<span class="hlt">earthquake</span> occurrence. We calculate the curvature along the major subduction zones of the world and show that past mega-<span class="hlt">earthquakes</span> occurred on flat (low-curvature) interfaces. A simplified analytic model demonstrates that shear strength heterogeneity increases with curvature. Stress loading on flat megathrusts is more homogeneous and hence more likely to be released simultaneously over large areas than on highly-curved faults. Therefore, the absence of asperities on large faults might counter-intuitively be a source of higher hazard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title10-vol2/pdf/CFR-2013-title10-vol2-sec100-23.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title10-vol2/pdf/CFR-2013-title10-vol2-sec100-23.pdf"><span>10 CFR 100.23 - Geologic and seismic siting criteria.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>... <span class="hlt">Earthquake</span> Ground Motion, and to permit adequate engineering solutions to actual or potential geologic and..., <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault geometry and slip <span class="hlt">rates</span>, site foundation material, and seismically induced... <span class="hlt">Earthquake</span> Ground Motion for the site, the potential for surface tectonic and nontectonic deformations, the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title10-vol2/pdf/CFR-2014-title10-vol2-sec100-23.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title10-vol2/pdf/CFR-2014-title10-vol2-sec100-23.pdf"><span>10 CFR 100.23 - Geologic and seismic siting criteria.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>... <span class="hlt">Earthquake</span> Ground Motion, and to permit adequate engineering solutions to actual or potential geologic and..., <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault geometry and slip <span class="hlt">rates</span>, site foundation material, and seismically induced... <span class="hlt">Earthquake</span> Ground Motion for the site, the potential for surface tectonic and nontectonic deformations, the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title10-vol2/pdf/CFR-2012-title10-vol2-sec100-23.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title10-vol2/pdf/CFR-2012-title10-vol2-sec100-23.pdf"><span>10 CFR 100.23 - Geologic and seismic siting criteria.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>... <span class="hlt">Earthquake</span> Ground Motion, and to permit adequate engineering solutions to actual or potential geologic and..., <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault geometry and slip <span class="hlt">rates</span>, site foundation material, and seismically induced... <span class="hlt">Earthquake</span> Ground Motion for the site, the potential for surface tectonic and nontectonic deformations, the...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001JSeis...5..147D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001JSeis...5..147D"><span>Cyclic migration of weak <span class="hlt">earthquakes</span> between Lunigiana <span class="hlt">earthquake</span> of October 10, 1995 and Reggio Emilia <span class="hlt">earthquake</span> of October 15, 1996 (Northern Italy)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>di Giovambattista, R.; Tyupkin, Yu</p> <p></p> <p>The cyclic migration of weak <span class="hlt">earthquakes</span> (M 2.2) which occurred during the yearprior to the October 15, 1996 (M = 4.9) Reggio Emilia <span class="hlt">earthquake</span> isdiscussed in this paper. The onset of this migration was associated with theoccurrence of the October 10, 1995 (M = 4.8) Lunigiana earthquakeabout 90 km southwest from the epicenter of the Reggio Emiliaearthquake. At least three series of <span class="hlt">earthquakes</span> migrating from theepicentral area of the Lunigiana <span class="hlt">earthquake</span> in the northeast direction wereobserved. The migration of <span class="hlt">earthquakes</span> of the first series terminated at adistance of about 30 km from the epicenter of the Reggio Emiliaearthquake. The <span class="hlt">earthquake</span> migration of the other two series halted atabout 10 km from the Reggio Emilia epicenter. The average <span class="hlt">rate</span> ofearthquake migration was about 200-300 km/year, while the time ofrecurrence of the observed cycles varied from 68 to 178 days. Weakearthquakes migrated along the transversal fault zones and sometimesjumped from one fault to another. A correlation between the migratingearthquakes and tidal variations is analysed. We discuss the hypothesis thatthe analyzed area is in a state of stress approaching the limit of thelong-term durability of crustal rocks and that the observed cyclic migrationis a result of a combination of a more or less regular evolution of tectonicand tidal variations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRB..122.6773V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRB..122.6773V"><span>Slow slip events in the early part of the <span class="hlt">earthquake</span> cycle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Voss, Nicholas K.; Malservisi, Rocco; Dixon, Timothy H.; Protti, Marino</p> <p>2017-08-01</p> <p>In February 2014 a <fi>M</fi><fi>w</fi> = 7.0 slow slip event (SSE) took place beneath the Nicoya Peninsula, Costa Rica. This event occurred 17 months after the 5 September 2012, <fi>M</fi><fi>w</fi> = 7.6, <span class="hlt">earthquake</span> and along the same subduction zone segment, during a period when significant postseismic deformation was ongoing. A second SSE occurred in the middle of 2015, 21 months after the 2014 SSE and 38 months after the <span class="hlt">earthquake</span>. The <span class="hlt">recurrence</span> interval for Nicoya SSEs was unchanged by the <span class="hlt">earthquake</span>. However, the spatial distribution of slip for the 2014 event differed significantly from previous events, having only deep ( 40 km) slip, compared to previous events, which had both deep and shallow slip. The 2015 SSE marked a return to the combination of deep plus shallow slip of preearthquake SSEs. However, slip magnitude in 2015 was nearly twice as large (<fi>M</fi><fi>w</fi> = 7.2) as preearthquake SSEs. We employ Coulomb Failure Stress change modeling in order to explain these changes. Stress changes associated with the <span class="hlt">earthquake</span> and afterslip were highest near the shallow portion of the megathrust, where preearthquake SSEs had significant slip. Lower stress change occurred on the deeper parts of the plate interface, perhaps explaining why the deep ( 40 km) region for SSEs remained unchanged. The large amount of shallow slip in the 2015 SSE may reflect lack of shallow slip in the prior SSE. These observations highlight the variability of aseismic strain release <span class="hlt">rates</span> throughout the <span class="hlt">earthquake</span> cycle.<abstract type="synopsis"><title type="main">Plain Language SummaryWe analyzed small signals in continuous GPS time series. By averaging many GPS measurements over a day, we are able to get very precise measurements of the motion of the ground. We found two events in the Nicoya Peninsula of Costa Rica where the GPS changed direction and began moving toward the oceanic trench in the opposite direction of subduction plate motion. These events are called slow</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFMGC43F..05A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFMGC43F..05A"><span>Future Earth: Reducing Loss By Automating Response to <span class="hlt">Earthquake</span> Shaking</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Allen, R. M.</p> <p>2014-12-01</p> <p><span class="hlt">Earthquakes</span> pose a significant threat to society in the U.S. and around the world. The risk is easily forgotten given the infrequent <span class="hlt">recurrence</span> of major damaging events, yet the likelihood of a major <span class="hlt">earthquake</span> in California in the next 30 years is greater than 99%. As our societal infrastructure becomes ever more interconnected, the potential impacts of these future events are difficult to predict. Yet, the same inter-connected infrastructure also allows us to rapidly detect <span class="hlt">earthquakes</span> as they begin, and provide seconds, tens or seconds, or a few minutes warning. A demonstration <span class="hlt">earthquake</span> early warning system is now operating in California and is being expanded to the west coast (www.ShakeAlert.org). In recent <span class="hlt">earthquakes</span> in the Los Angeles region, alerts were generated that could have provided warning to the vast majority of Los Angelinos who experienced the shaking. Efforts are underway to build a public system. Smartphone technology will be used not only to issue that alerts, but could also be used to collect data, and improve the warnings. The MyShake project at UC Berkeley is currently testing an app that attempts to turn millions of smartphones into <span class="hlt">earthquake</span>-detectors. As our development of the technology continues, we can anticipate ever-more automated response to <span class="hlt">earthquake</span> alerts. Already, the BART system in the San Francisco Bay Area automatically stops trains based on the alerts. In the future, elevators will stop, machinery will pause, hazardous materials will be isolated, and self-driving cars will pull-over to the side of the road. In this presentation we will review the current status of the <span class="hlt">earthquake</span> early warning system in the US. We will illustrate how smartphones can contribute to the system. Finally, we will review applications of the information to reduce future losses.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24877254','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24877254"><span>Prediction of non-biochemical <span class="hlt">recurrence</span> <span class="hlt">rate</span> after radical prostatectomy in a Japanese cohort: development of a postoperative nomogram.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Okubo, Hidenori; Ohori, Makoto; Ohno, Yoshio; Nakashima, Jun; Inoue, Rie; Nagao, Toshitaka; Tachibana, Masaaki</p> <p>2014-05-01</p> <p>To develop a nomogram based on postoperative factors and prostate-specific antigen levels to predict the non-biochemical <span class="hlt">recurrence</span> <span class="hlt">rate</span> after radical prostatectomy ina Japanese cohort. A total of 606 Japanese patients with T1-3N0M0 prostate cancer who underwent radical prostatectomy and pelvic lymph node dissection at Tokyo Medical University hospital from 2000 to 2010 were studied. A nomogram was constructed based on Cox hazard regression analysis evaluating the prognostic significance of serum prostate-specific antigen and pathological factors in the radical prostatectomy specimens. The discriminating ability of the nomogram was assessed by the concordance index (C-index), and the predicted and actual outcomes were compared with a bootstrapped calibration plot. With a mean follow up of 60.0 months, a total of 187 patients (30.9%) experienced biochemical <span class="hlt">recurrence</span>, with a 5-year non-biochemical <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 72.3%. Based on a Cox hazard regression model, a nomogram was constructed to predict non-biochemical <span class="hlt">recurrence</span> using serum prostate-specific antigen level and pathological features in radical prostatectomy specimens. The concordance index was 0.77, and the calibration plots appeared to be accurate. The postoperative nomogram described here can provide valuable information regarding the need for adjuvant/salvage radiation or hormonal therapy in patients after radical prostatectomy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018PhDT.........4M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018PhDT.........4M"><span>Evidence of the 1762 Arakan and Prior <span class="hlt">Earthquakes</span> in the Northern Sunda Subduction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mondal, Dhiman Ranjan</p> <p></p> <p>The objective of this dissertation is to understand the seismic hazard associated with Arakan segment of the northern Sunda subduction along SE Bangladesh. In order to do that, it is necessary to document geologic evidence for the 1762 Arakan <span class="hlt">earthquake</span> and prior events, to help estimate the <span class="hlt">recurrence</span> interval (repeat time) for that <span class="hlt">earthquake</span>. Historical records described that the 1762 <span class="hlt">earthquake</span> caused extensive damage along the Arakan segment of the Sunda subduction system. But the geologic evidence for the <span class="hlt">earthquake</span> farther north is necessary to better understand its associated seismic hazard to the densely populated nation of Bangladesh. This dissertation presents the results obtained from U/Th dating of the dead and live coral microatolls including their elevations measured by high precision GPS from the Saint Martin's Island, DEM analysis and elevation of terraces from Teknaf coast and fault dislocation modeling based on the data obtained from the Saint Martin's Island and Teknaf. Coral microatolls from Saint Martin's island documents the evidence of the 1762 and prior <span class="hlt">earthquakes</span>. The U/Th ages documents strong evidence of microatoll die offs related to the 1762 <span class="hlt">earthquake</span>. The > 2 m elevation difference between the dead microatolls and present-day living corals suggest that the microatolls died due to the coseismic uplift of 1762 Arakan <span class="hlt">earthquake</span>. This dissertation also provides evidence for two additional <span class="hlt">earthquakes</span> taking place in 700 and 1140 C.E. which suggests an <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> interval of 500 years. Geomorphic studies documented three terraces along the coast of Teknaf. Several marine terraces have been previously documented along the west coast of Myanmar. The youngest of these terraces has been correlated to the coseismic uplift of 1762 Arakan along the Myanmar coast. The terraces along the coast of Teknaf are characterized by flat to semi-flat surfaces followed by sharp topographic rises. DEM (Digital Elevation System) analysis and GPS</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28589253','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28589253"><span>Early PET imaging with [68]Ga-PSMA-11 increases the detection <span class="hlt">rate</span> of local <span class="hlt">recurrence</span> in prostate cancer patients with biochemical <span class="hlt">recurrence</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Uprimny, Christian; Kroiss, Alexander Stephan; Fritz, Josef; Decristoforo, Clemens; Kendler, Dorota; von Guggenberg, Elisabeth; Nilica, Bernhard; Maffey-Steffan, Johanna; di Santo, Gianpaolo; Bektic, Jasmin; Horninger, Wolfgang; Virgolini, Irene Johanna</p> <p>2017-09-01</p> <p>PET/CT using 68 Ga-labelled prostate-specific membrane antigen PSMA-11 (HBEDD-CC) has emerged as a promising imaging method in the diagnostic evaluation of prostate cancer (PC) patients with biochemical <span class="hlt">recurrence</span>. However, assessment of local <span class="hlt">recurrence</span> (LR) may be limited by intense physiologic tracer accumulation in the urinary bladder on whole-body scans, normally conducted 60 min post-tracer injection (p.i.). It could be shown on early dynamic imaging studies that 68 Ga-PSMA-11 uptake in PC lesions occurs earlier than tracer accumulation in the urinary bladder. This study aims to investigate whether early static PET acquisition increases detection <span class="hlt">rate</span> of local <span class="hlt">recurrence</span> on 68 Ga-PSMA-11 PET/CT in comparison to PET imaging 60 min p.i.. 203 consecutive PC patients with biochemical failure referred to 68 Ga-PSMA-11 PET/CT were analysed retrospectively (median prostate specific antigen (PSA) value: 1.44 ng/ml). In addition to whole-body PET/CT scans 60 min p.i., early static imaging of the pelvis was performed, starting at a median time of 283 s p.i. (range: 243-491 s). Assessment was based on visual analysis and calculation of maximum standardized uptake value (SUV max ) of pathologic lesions present in the pelvic area found on early PET imaging and on 60 min-PET scans. 26 patients (12.8%) were judged positive for LR on PET scans 60 min p.i. (median SUV max : 10.8; range: 4.7-40.9), whereas 50 patients (24.6%) revealed a lesion suggestive of LR on early PET imaging (median SUV max : 5.9; range: 2.9-17.6), resulting in a significant rise in detection <span class="hlt">rate</span> (p < 0.001). Equivocal findings on PET scans 60 min p.i. decreased significantly with the help of early imaging (15.8% vs. 4.5% of patients; p < 0.001). Tracer activity in the urinary bladder with a median SUV max of 8.2 was present in 63 patients on early PET scans (31.0%). However, acquisition starting time of early PET scans differed significantly in the patient groups with and without urinary</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T51C2889H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T51C2889H"><span>Repeating <span class="hlt">Earthquakes</span> on the Queen Charlotte Plate Boundary</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hayward, T. W.; Bostock, M. G.</p> <p>2015-12-01</p> <p>The Queen Charlotte Fault (QCF) is a major plate boundary located off the northwest coast of North America that has produced large <span class="hlt">earthquakes</span> in 1949 (M8.1) and more recently in October, 2012 (M7.8). The 2012 event was dominated by thrusting despite the fact that plate motions at the boundary are nearly transcurrent. It is now widely believed that the plate boundary comprises the QCF (i.e., a dextral strike-slip fault) as well as an element of subduction of the Pacific Plate beneath the North American Plate. Repeating <span class="hlt">earthquakes</span> and seismic tremor have been observed in the vicinity of the QCF; providing insight into the spatial and temporal characteristics of repeating <span class="hlt">earthquakes</span> is the goal of this research. Due to poor station coverage and data quality, traditional methods of locating <span class="hlt">earthquakes</span> are not applicable to these events. Instead, we have implemented an algorithm to locate local (i.e., < 100 km distance to epicenter) <span class="hlt">earthquakes</span> using a single, three-component seismogram. This algorithm relies on the P-wave polarization and, through comparison with larger local events in the Geological Survey of Canada catalogue, is shown to yield epicentral locations accurate to within 5-10 km. A total of 24 unique families of repeating <span class="hlt">earthquakes</span> has been identified, and 4 of these families have been located with high confidence. Their epicenters locate directly on the trace of the QCF and their depths are shallow (i.e., 5-15 km), consistent with the proposed depth of the QCF. Analysis of temporal <span class="hlt">recurrence</span> leading up to the 2012 M7.8 event reveals a non-random pattern, with an approximately 15 day periodicity. Further analysis is planned to study whether this behaviour persists after the 2012 event and to gain insight into the effects of the 2012 event on the stress field and frictional properties of the plate boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22172852','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22172852"><span><span class="hlt">Rate</span> of tumor growth predicts <span class="hlt">recurrence</span> of hepatocellular carcinoma after liver transplantation in patients beyond Milan or UCSF criteria.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hanouneh, I A; Macaron, C; Lopez, R; Aucejo, F; Zein, N N</p> <p>2011-12-01</p> <p>It is likely that some patients whose tumor burdens exceed the current transplant criteria have favorable tumor biology, and that these patients would have low risk of tumor <span class="hlt">recurrence</span> after liver transplantation (LT). To assess the <span class="hlt">rate</span> of tumor growth as selection criteria for LT in patients with hepatocellular carcinoma (HCC). We identified all patients who underwent LT for HCC in our institution from 2002 to 2008. Total tumor volume (TTV) was calculated as the sum of the volumes of all tumors on pretransplantation imaging [(4/3)πr3, where r is the maximum radius of each HCC]. The <span class="hlt">rate</span> of tumor growth was calculated as per-month change in TTV on sequential pretransplantation imaging before any locoregional therapy. A Kaplan-Meier plot was constructed and Cox regression analysis performed. Ninety-two patients were included in the study. The median follow-up was 19.5 (range 10.7-30.7) months during which 12 patients (13%) experienced <span class="hlt">recurrence</span> of HCC. Twenty-four patients (26%) had HCC beyond the Milan criteria, and the overall survival <span class="hlt">rate</span> of the entire group was 72%. Higher pre-LT alpha-fetoprotein (hazard ratio [HR] 1.01; P=.001), poorly differentiated tumors (HR 13; P=.039), the presence of microvascular invasion (HR 7.9; P=.001), higher TTV (HR 1.03; P<.001), and faster tumor growth (HR 1.09; P<.001) were significantly associated with the risk of <span class="hlt">recurrence</span>. A cutoff value of tumor growth of 1.61 cm3/mo was chosen on the basis of the risk of <span class="hlt">recurrence</span> with the use of a receiver operating characteristic curve. Patients beyond the Milan criteria with tumor growth<1.61 cm3/mo experienced less <span class="hlt">recurrence</span> (11% vs 58%; P=.023) than those beyond the Milan criteria with tumor growth>1.61 cm3/mo. Similarly, <span class="hlt">rate</span> of tumor growth predicted HCC <span class="hlt">recurrence</span> in those beyond the University of California of San Francisco (UCSF) criteria. Patients with slowly growing tumor who would be currently excluded from LT because tumor burden exceeds traditional Milan and UCSF</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRB..11612111S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRB..11612111S"><span>A reevaluation of the Pallett Creek <span class="hlt">earthquake</span> chronology based on new AMS radiocarbon dates, San Andreas fault, California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scharer, Katherine M.; Biasi, Glenn P.; Weldon, Ray J., II</p> <p>2011-12-01</p> <p>The Pallett Creek paleoseismic record occupies a keystone position in most attempts to develop rupture histories for the southern San Andreas fault. Previous estimates of <span class="hlt">earthquake</span> ages at Pallett Creek were determined by decay counting radiocarbon methods. That method requires large samples which can lead to unaccounted sources of uncertainty in radiocarbon ages because of the heterogeneous composition of organic layers. In contrast, accelerator mass spectrometry (AMS) radiocarbon dates may be obtained from small samples that have known carbon sources and also allow for a more complete sampling of the section. We present 65 new AMS radiocarbon dates that span nine ground-rupturing <span class="hlt">earthquakes</span> at Pallett Creek. Overall, the AMS dates are similar to and reveal no dramatic bias in the conventional dates. For many layers, however, individual charcoal samples were younger than the conventional dates, leading to <span class="hlt">earthquake</span> ages that are overall slightly younger than previously reported. New <span class="hlt">earthquake</span> ages are determined by Bayesian refinement of the layer ages based on stratigraphic ordering and sedimentological constraints. The new chronology is more regular than previously published records in large part due to new samples constraining the age of event R. The closed interval from event C to 1857 has a mean <span class="hlt">recurrence</span> of 135 years (σ = 83.2 years) and a quasiperiodic coefficient of variation (COV) of 0.61. We show that the new dates and resultant <span class="hlt">earthquake</span> chronology have a stronger effect on COV than the specific membership of this long series and dating precision improvements from sedimentation <span class="hlt">rates</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018CG....111..244G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018CG....111..244G"><span>Determining on-fault <span class="hlt">earthquake</span> magnitude distributions from integer programming</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geist, Eric L.; Parsons, Tom</p> <p>2018-02-01</p> <p><span class="hlt">Earthquake</span> magnitude distributions among faults within a fault system are determined from regional seismicity and fault slip <span class="hlt">rates</span> using binary integer programming. A synthetic <span class="hlt">earthquake</span> catalog (i.e., list of randomly sampled magnitudes) that spans millennia is first formed, assuming that regional seismicity follows a Gutenberg-Richter relation. Each <span class="hlt">earthquake</span> in the synthetic catalog can occur on any fault and at any location. The objective is to minimize misfits in the target slip <span class="hlt">rate</span> for each fault, where slip for each <span class="hlt">earthquake</span> is scaled from its magnitude. The decision vector consists of binary variables indicating which locations are optimal among all possibilities. Uncertainty estimates in fault slip <span class="hlt">rates</span> provide explicit upper and lower bounding constraints to the problem. An implicit constraint is that an <span class="hlt">earthquake</span> can only be located on a fault if it is long enough to contain that <span class="hlt">earthquake</span>. A general mixed-integer programming solver, consisting of a number of different algorithms, is used to determine the optimal decision vector. A case study is presented for the State of California, where a 4 kyr synthetic <span class="hlt">earthquake</span> catalog is created and faults with slip ≥3 mm/yr are considered, resulting in >106 variables. The optimal magnitude distributions for each of the faults in the system span a rich diversity of shapes, ranging from characteristic to power-law distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70197114','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70197114"><span>Determining on-fault <span class="hlt">earthquake</span> magnitude distributions from integer programming</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Geist, Eric L.; Parsons, Thomas E.</p> <p>2018-01-01</p> <p><span class="hlt">Earthquake</span> magnitude distributions among faults within a fault system are determined from regional seismicity and fault slip <span class="hlt">rates</span> using binary integer programming. A synthetic <span class="hlt">earthquake</span> catalog (i.e., list of randomly sampled magnitudes) that spans millennia is first formed, assuming that regional seismicity follows a Gutenberg-Richter relation. Each <span class="hlt">earthquake</span> in the synthetic catalog can occur on any fault and at any location. The objective is to minimize misfits in the target slip <span class="hlt">rate</span> for each fault, where slip for each <span class="hlt">earthquake</span> is scaled from its magnitude. The decision vector consists of binary variables indicating which locations are optimal among all possibilities. Uncertainty estimates in fault slip <span class="hlt">rates</span> provide explicit upper and lower bounding constraints to the problem. An implicit constraint is that an <span class="hlt">earthquake</span> can only be located on a fault if it is long enough to contain that <span class="hlt">earthquake</span>. A general mixed-integer programming solver, consisting of a number of different algorithms, is used to determine the optimal decision vector. A case study is presented for the State of California, where a 4 kyr synthetic <span class="hlt">earthquake</span> catalog is created and faults with slip ≥3 mm/yr are considered, resulting in >106  variables. The optimal magnitude distributions for each of the faults in the system span a rich diversity of shapes, ranging from characteristic to power-law distributions. </p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=earth+AND+quakes&id=EJ194839','ERIC'); return false;" href="https://eric.ed.gov/?q=earth+AND+quakes&id=EJ194839"><span><span class="hlt">Earthquakes</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Walter, Edward J.</p> <p>1977-01-01</p> <p>Presents an analysis of the causes of <span class="hlt">earthquakes</span>. Topics discussed include (1) geological and seismological factors that determine the effect of a particular <span class="hlt">earthquake</span> on a given structure; (2) description of some large <span class="hlt">earthquakes</span> such as the San Francisco quake; and (3) prediction of <span class="hlt">earthquakes</span>. (HM)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoRL..42.7366Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoRL..42.7366Z"><span>Possible seasonality in large deep-focus <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhan, Zhongwen; Shearer, Peter M.</p> <p>2015-09-01</p> <p>Large deep-focus <span class="hlt">earthquakes</span> (magnitude > 7.0, depth > 500 km) have exhibited strong seasonality in their occurrence times since the beginning of global <span class="hlt">earthquake</span> catalogs. Of 60 such events from 1900 to the present, 42 have occurred in the middle half of each year. The seasonality appears strongest in the northwest Pacific subduction zones and weakest in the Tonga region. Taken at face value, the surplus of northern hemisphere summer events is statistically significant, but due to the ex post facto hypothesis testing, the absence of seasonality in smaller deep <span class="hlt">earthquakes</span>, and the lack of a known physical triggering mechanism, we cannot rule out that the observed seasonality is just random chance. However, we can make a testable prediction of seasonality in future large deep-focus <span class="hlt">earthquakes</span>, which, given likely <span class="hlt">earthquake</span> occurrence <span class="hlt">rates</span>, should be verified or falsified within a few decades. If confirmed, deep <span class="hlt">earthquake</span> seasonality would challenge our current understanding of deep <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26045058','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26045058"><span>Estimating the <span class="hlt">Recurrence</span> <span class="hlt">Rate</span> of Gestational Diabetes Mellitus (GDM) in Massachusetts 1998-2007: Methods and Findings.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>England, Lucinda; Kotelchuck, Milton; Wilson, Hoyt G; Diop, Hafsatou; Oppedisano, Paul; Kim, Shin Y; Cui, Xiaohui; Shapiro-Mendoza, Carrie K</p> <p>2015-10-01</p> <p>Women with gestational diabetes mellitus (GDM) may be able to reduce their risk of <span class="hlt">recurrent</span> GDM and progression to type 2 diabetes mellitus through lifestyle change; however, there is limited population-based information on GDM <span class="hlt">recurrence</span> <span class="hlt">rates</span>. We used data from a population of women delivering two sequential live singleton infants in Massachusetts (1998-2007) to estimate the prevalence of chronic diabetes mellitus (CDM) and GDM in parity one pregnancies and <span class="hlt">recurrence</span> of GDM and progression from GDM to CDM in parity two pregnancies. We examined four diabetes classification approaches; birth certificate (BC) data alone, hospital discharge (HD) data alone, both sources hierarchically combined with a diagnosis of CDM from either source taking priority over a diagnosis of GDM, and both sources combined including only pregnancies with full agreement in diagnosis. Descriptive statistics were used to describe population characteristics, prevalence of CDM and GDM, and <span class="hlt">recurrence</span> of diabetes in successive pregnancies. Diabetes classification agreement was assessed using the Kappa statistic. Associated maternal characteristics were examined through adjusted model-based t tests and Chi square tests. A total of 134,670 women with two sequential deliveries of parities one and two were identified. While there was only slight agreement on GDM classification across HD and BC records, estimates of GDM <span class="hlt">recurrence</span> were fairly consistent; nearly half of women with GDM in their parity one pregnancy developed GDM in their subsequent pregnancy. While estimates of progression from GDM to CDM across sequential pregnancies were more variable, all approaches yielded estimates of ≤5 %. The development of either GDM or CDM following a parity one pregnancy with no diagnosis of diabetes was <3 % across approaches. Women with <span class="hlt">recurrent</span> GDM were disproportionately older and foreign born. <span class="hlt">Recurrent</span> GDM is a serious life course public health issue; the inter-pregnancy interval provides an</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S44C..05K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S44C..05K"><span>Using regional pore-fluid pressure response following the 3 Sep 2016 M­­w5.8 Pawnee, Oklahoma <span class="hlt">earthquake</span> to constrain far-field seismicity <span class="hlt">rate</span> forecasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kroll, K.; Murray, K. E.; Cochran, E. S.</p> <p>2016-12-01</p> <p>The 3 Sep 2016 M­­w5.8 Pawnee, Oklahoma <span class="hlt">earthquake</span> was the largest event to occur in recorded history of the state. Widespread shaking from the event was felt in seven central U.S. states and caused damage as far away as Oklahoma City ( 115 km SSW). The Pawnee <span class="hlt">earthquake</span> occurred soon after the deployment of a subsurface pore-fluid pressure monitoring network in Aug 2016. Eight pressure transducers were installed downhole in inactive saltwater disposal wells that were completed in the basal sedimentary zone (the Arbuckle Group). The transducers are located in Alfalfa, Grant, and Payne Counties at distances of 48 to 140 km from the Pawnee <span class="hlt">earthquake</span>. We observed coseismic fluid pressure changes in all monitoring wells, indicating a large-scale poroelastic response in the Arbuckle. Two wells in Payne County lie in a zone of volumetric compression 48-52 km SSE of the rupture and experienced a co-seismic rise in fluid pressures that we conclude was related to poroelastic rebound of the Arbuckle reservoir. We compare measurements of the pore-fluid pressure change to estimated values given by the product of the volumetric strain, a Skempton's coefficient of 0.33, and a Bulk modulus of 25 GPa for fractured granitic basement rocks. We explore the possibility that the small increase in pore-fluid pressure may increase the <span class="hlt">rate</span> of seismicity in regions outside of the mainshock region. We test this hypothesis by supplementing the Oklahoma Geological Survey <span class="hlt">earthquake</span> catalog by semi-automated detection smaller magnitude (<2.6 M) <span class="hlt">earthquakes</span> on seismic stations that are located in the vicinity of the wells. Using the events that occur in the week before the mainshock (27 Aug to 3 Sep 2016) as the background seismicity <span class="hlt">rate</span> and the estimated pore-fluid pressure increase, we use a <span class="hlt">rate</span>-state model to predict the seismicity <span class="hlt">rate</span> change in the week following the event. We then compare the model predictions to the observed seismicity in the week following the Pawnee <span class="hlt">earthquake</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70029116','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70029116"><span>A hypothesis for delayed dynamic <span class="hlt">earthquake</span> triggering</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Parsons, T.</p> <p>2005-01-01</p> <p>It's uncertain whether more near-field <span class="hlt">earthquakes</span> are triggered by static or dynamic stress changes. This ratio matters because static <span class="hlt">earthquake</span> interactions are increasingly incorporated into probabilistic forecasts. Recent studies were unable to demonstrate all predictions from the static-stress-change hypothesis, particularly seismicity <span class="hlt">rate</span> reductions. However, current dynamic stress change hypotheses do not explain delayed <span class="hlt">earthquake</span> triggering and Omori's law. Here I show numerically that if seismic waves can alter some frictional contacts in neighboring fault zones, then dynamic triggering might cause delayed triggering and an Omori-law response. The hypothesis depends on faults following a <span class="hlt">rate</span>/state friction law, and on seismic waves changing the mean critical slip distance (Dc) at nucleation zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S53C..03C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S53C..03C"><span>A Geophysical Study of the Cadell Fault Scarp for <span class="hlt">Earthquake</span> Hazard Assessment in Southeast Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Collins, C. D.</p> <p>2004-12-01</p> <p>The historical record of seismicity in Australia is too short (less than 150 years) to confidently define seismic source zones, particularly the <span class="hlt">recurrence</span> <span class="hlt">rates</span> for large, potentially damaging <span class="hlt">earthquakes</span>, and this leads to uncertainty in hazard assessments. One way to extend this record is to search for evidence of <span class="hlt">earthquakes</span> in the landscape, including Quaternary fault scarps, tilt blocks and disruptions to drainage patterns. A recent Geoscience Australia compilation of evidence of Quaternary tectonics identified over one hundred examples of potentially recent structures in Australia, testifying to the fact that a greater hazard may exist from large <span class="hlt">earthquakes</span> than is evident from the recorded history alone. Most of these structures have not been studied in detail and have not been dated, so the <span class="hlt">recurrence</span> <span class="hlt">rate</span> for damaging events is unknown. One example of recent tectonic activity lies on the Victoria-New South Wales border, where geologically recent uplift has resulted in the formation of the Cadell Fault Scarp, damming Australia's largest river, the Murray River, and diverting its course. The scarp extends along a north-south strike for at least 50 km and reaches a maximum height of about 13 metres. The scarp displaces sands and clays of the Murray Basin sediments which overlie Palaeozoic bedrock at a depth of 100 to 250 m. There is evidence that the river system has eroded the scarp and displaced the topographic expression away from the location where the fault, or faults, meets the surface. Thus, to locate potential sites for trenching which intersect the faults, Geoscience Australia acquired ground-penetrating radar, resistivity and multi-channel high-resolution seismic reflection and refraction data along traverses across the scarp. The seismic data were acquired using an IVI T15000 MiniVib vibrator operating in p-wave mode, and a 24-channel Stratavisor acquisition system. Four 10-second sweeps, with a frequency range of 10-240 Hz, were carried out</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED241329.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED241329.pdf"><span><span class="hlt">Earthquakes</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Pakiser, Louis C.</p> <p></p> <p>One of a series of general interest publications on science topics, the booklet provides those interested in <span class="hlt">earthquakes</span> with an introduction to the subject. Following a section presenting an historical look at the world's major <span class="hlt">earthquakes</span>, the booklet discusses <span class="hlt">earthquake</span>-prone geographic areas, the nature and workings of <span class="hlt">earthquakes</span>, earthquake…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27475933','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27475933"><span>Long-term results and <span class="hlt">recurrence</span> <span class="hlt">rates</span> after spironolactone treatment in non-resolving central serous chorio-retinopathy (CSCR).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Herold, Tina Rike; Rist, Kristina; Priglinger, Siegfried Georg; Ulbig, Michael Werner; Wolf, Armin</p> <p>2017-02-01</p> <p>To evaluate the long-term results of spironolactone in non-resolving central serous chorio-retinopathy (CSCR) and <span class="hlt">recurrence</span> <span class="hlt">rates</span> of CSCR. Interventional uncontrolled open-label prospective clinical trial of patients with non-resolving CSCR who were treated with spironolactone 50 mg daily (Spironolacton AL® 50 mg, ALIUD PHARMA) for up to 16 weeks. Follow-up visits were performed at 3, 6, 9, and 12 months. Retreatment criteria for <span class="hlt">recurrence</span> were: gain in sub-retinal fluid (SRF) of more than 25 % plus/or increase of central retinal thickness (CRT) of more than 50 μm plus visual symptoms compared to last visit. 12-month efficacy of upload treatment with spironolactone. Secondary outcome measure was the <span class="hlt">recurrence</span> <span class="hlt">rate</span> at 6, 9, and 12 months. Of the 21 study eyes treated, 71 % (n = 15) showed significant improvement or complete regression on OCT examination over 12 months. Nineteen percent of the patients (n = 4) showed a stable course from visit 1 to visit 12. The overall reduction of sub-retinal fluid from visit 1 (156 μm ± 131 SD) to visit 12 (53 μm ± 93 SD) was statistically significant (p = 0.003). The change of mean visual acuity (log MAR) from 0.25 (± 0.17 SD) at baseline to 0.17 (± 0.18 SD) at visit 12 was statistically significant, with p = 0.044. Our results confirm a positive effect of spironolactone in non-resolving CSCR in 71 % of cases. Evaluation of <span class="hlt">recurrence</span> <span class="hlt">rates</span> and retreatments showed good results in patients who responded to spironolactone primarily. A prospective randomized trial may provide better data about this non-invasive treatment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.T51A2448J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T51A2448J"><span>The EM <span class="hlt">Earthquake</span> Precursor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jones, K. B., II; Saxton, P. T.</p> <p>2013-12-01</p> <p>Many attempts have been made to determine a sound forecasting method regarding <span class="hlt">earthquakes</span> and warn the public in turn. Presently, the animal kingdom leads the precursor list alluding to a transmission related source. By applying the animal-based model to an electromagnetic (EM) wave model, various hypotheses were formed, but the most interesting one required the use of a magnetometer with a differing design and geometry. To date, numerous, high-end magnetometers have been in use in close proximity to fault zones for potential <span class="hlt">earthquake</span> forecasting; however, something is still amiss. The problem still resides with what exactly is forecastable and the investigating direction of EM. After the 1989 Loma Prieta <span class="hlt">Earthquake</span>, American <span class="hlt">earthquake</span> investigators predetermined magnetometer use and a minimum <span class="hlt">earthquake</span> magnitude necessary for EM detection. This action was set in motion, due to the extensive damage incurred and public outrage concerning <span class="hlt">earthquake</span> forecasting; however, the magnetometers employed, grounded or buried, are completely subject to static and electric fields and have yet to correlate to an identifiable precursor. Secondly, there is neither a networked array for finding any epicentral locations, nor have there been any attempts to find even one. This methodology needs dismissal, because it is overly complicated, subject to continuous change, and provides no response time. As for the minimum magnitude threshold, which was set at M5, this is simply higher than what modern technological advances have gained. Detection can now be achieved at approximately M1, which greatly improves forecasting chances. A propagating precursor has now been detected in both the field and laboratory. Field antenna testing conducted outside the NE Texas town of Timpson in February, 2013, detected three strong EM sources along with numerous weaker signals. The antenna had mobility, and observations were noted for <span class="hlt">recurrence</span>, duration, and frequency response. Next, two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70018466','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70018466"><span>Implications of fault constitutive properties for <span class="hlt">earthquake</span> prediction</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Dieterich, J.H.; Kilgore, B.</p> <p>1996-01-01</p> <p>The <span class="hlt">rate</span>- and state-dependent constitutive formulation for fault slip characterizes an exceptional variety of materials over a wide range of sliding conditions. This formulation provides a unified representation of diverse sliding phenomena including slip weakening over a characteristic sliding distance D(c), apparent fracture energy at a rupture front, time- dependent healing after rapid slip, and various other transient and slip <span class="hlt">rate</span> effects. Laboratory observations and theoretical models both indicate that <span class="hlt">earthquake</span> nucleation is accompanied by long intervals of accelerating slip. Strains from the nucleation process on buried faults generally could not be detected if laboratory values of D, apply to faults in nature. However, scaling of D(c) is presently an open question and the possibility exists that measurable premonitory creep may precede some <span class="hlt">earthquakes</span>. <span class="hlt">Earthquake</span> activity is modeled as a sequence of <span class="hlt">earthquake</span> nucleation events. In this model, <span class="hlt">earthquake</span> clustering arises from sensitivity of nucleation times to the stress changes induced by prior <span class="hlt">earthquakes</span>. The model gives the characteristic Omori aftershock decay law and assigns physical interpretation to aftershock parameters. The seismicity formulation predicts large changes of <span class="hlt">earthquake</span> probabilities result from stress changes. Two mechanisms for foreshocks are proposed that describe observed frequency of occurrence of foreshock-mainshock pairs by time and magnitude. With the first mechanism, foreshocks represent a manifestation of <span class="hlt">earthquake</span> clustering in which the stress change at the time of the foreshock increases the probability of <span class="hlt">earthquakes</span> at all magnitudes including the eventual mainshock. With the second model, accelerating fault slip on the mainshock nucleation zone triggers foreshocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39438','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39438"><span>Implications of fault constitutive properties for <span class="hlt">earthquake</span> prediction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dieterich, J H; Kilgore, B</p> <p>1996-01-01</p> <p>The <span class="hlt">rate</span>- and state-dependent constitutive formulation for fault slip characterizes an exceptional variety of materials over a wide range of sliding conditions. This formulation provides a unified representation of diverse sliding phenomena including slip weakening over a characteristic sliding distance Dc, apparent fracture energy at a rupture front, time-dependent healing after rapid slip, and various other transient and slip <span class="hlt">rate</span> effects. Laboratory observations and theoretical models both indicate that <span class="hlt">earthquake</span> nucleation is accompanied by long intervals of accelerating slip. Strains from the nucleation process on buried faults generally could not be detected if laboratory values of Dc apply to faults in nature. However, scaling of Dc is presently an open question and the possibility exists that measurable premonitory creep may precede some <span class="hlt">earthquakes</span>. <span class="hlt">Earthquake</span> activity is modeled as a sequence of <span class="hlt">earthquake</span> nucleation events. In this model, <span class="hlt">earthquake</span> clustering arises from sensitivity of nucleation times to the stress changes induced by prior <span class="hlt">earthquakes</span>. The model gives the characteristic Omori aftershock decay law and assigns physical interpretation to aftershock parameters. The seismicity formulation predicts large changes of <span class="hlt">earthquake</span> probabilities result from stress changes. Two mechanisms for foreshocks are proposed that describe observed frequency of occurrence of foreshock-mainshock pairs by time and magnitude. With the first mechanism, foreshocks represent a manifestation of <span class="hlt">earthquake</span> clustering in which the stress change at the time of the foreshock increases the probability of <span class="hlt">earthquakes</span> at all magnitudes including the eventual mainshock. With the second model, accelerating fault slip on the mainshock nucleation zone triggers foreshocks. Images Fig. 3 PMID:11607666</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11607666','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11607666"><span>Implications of fault constitutive properties for <span class="hlt">earthquake</span> prediction.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dieterich, J H; Kilgore, B</p> <p>1996-04-30</p> <p>The <span class="hlt">rate</span>- and state-dependent constitutive formulation for fault slip characterizes an exceptional variety of materials over a wide range of sliding conditions. This formulation provides a unified representation of diverse sliding phenomena including slip weakening over a characteristic sliding distance Dc, apparent fracture energy at a rupture front, time-dependent healing after rapid slip, and various other transient and slip <span class="hlt">rate</span> effects. Laboratory observations and theoretical models both indicate that <span class="hlt">earthquake</span> nucleation is accompanied by long intervals of accelerating slip. Strains from the nucleation process on buried faults generally could not be detected if laboratory values of Dc apply to faults in nature. However, scaling of Dc is presently an open question and the possibility exists that measurable premonitory creep may precede some <span class="hlt">earthquakes</span>. <span class="hlt">Earthquake</span> activity is modeled as a sequence of <span class="hlt">earthquake</span> nucleation events. In this model, <span class="hlt">earthquake</span> clustering arises from sensitivity of nucleation times to the stress changes induced by prior <span class="hlt">earthquakes</span>. The model gives the characteristic Omori aftershock decay law and assigns physical interpretation to aftershock parameters. The seismicity formulation predicts large changes of <span class="hlt">earthquake</span> probabilities result from stress changes. Two mechanisms for foreshocks are proposed that describe observed frequency of occurrence of foreshock-mainshock pairs by time and magnitude. With the first mechanism, foreshocks represent a manifestation of <span class="hlt">earthquake</span> clustering in which the stress change at the time of the foreshock increases the probability of <span class="hlt">earthquakes</span> at all magnitudes including the eventual mainshock. With the second model, accelerating fault slip on the mainshock nucleation zone triggers foreshocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S53F..08T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S53F..08T"><span>Using low-frequency <span class="hlt">earthquake</span> families on the San Andreas fault as deep creepmeters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thomas, A.; Beeler, N. M.; Bletery, Q.; Burgmann, R.; Shelly, D. R.</p> <p>2017-12-01</p> <p>The San Andreas fault hosts tectonic tremor and low-frequency <span class="hlt">earthquakes</span> (LFEs) similar to those in subduction zone environments. These LFEs are grouped into families based on waveform similarity and locate between 16 and 29 km depth along a 150-km-long section of the fault centered on Parkfield, CA. ­Within individual LFE families event occurrence is not steady. In some families, bursts of a few events recur on timescales of days while in other families there are nearly quiescent periods that often last for months followed by episodes where hundreds of events occur over the course of a few days. These two different styles of LFE occurrence are called continuous and episodic respectively. LFEs are often assumed to reflect persistent regions that periodically fail during the aseismic shear of the surrounding fault allowing them to be used as creepmeters. We test this idea by formalizing the definition of a creepmeter (the LFE occurrence <span class="hlt">rate</span> is proportional to the local fault slip <span class="hlt">rate</span>), determining whether this definition is consistent with the observations, and over what timescale. We use the <span class="hlt">recurrence</span> intervals of LFEs within individual families to create a catalog of LFE bursts. For the episodic families, we consider both longer duration (multiday) inferred creep episodes (dubbed long-timescale episodic) as well as the frequent short-term bursts of events that occur many times during inferred creep episodes (dubbed short-timescale episodic). We then use the <span class="hlt">recurrence</span> intervals of LFE bursts to estimate the timing, duration, <span class="hlt">recurrence</span> interval, slip, and slip <span class="hlt">rate</span> associated with inferred slow slip events. We find that continuous families and the short-timescale episodic families appear to be inconsistent with our definition of a creepmeter (defined on the <span class="hlt">recurrence</span> interval timescale) because their estimated durations are not physically meaningful. A straight-forward interpretation of the frequent short-term bursts of the continuous and short</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.sciencemag.org/content/347/6224/830','USGSPUBS'); return false;" href="http://www.sciencemag.org/content/347/6224/830"><span>Coping with <span class="hlt">earthquakes</span> induced by fluid injection</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McGarr, Arthur F.; Bekins, Barbara; Burkardt, Nina; Dewey, James W.; Earle, Paul S.; Ellsworth, William L.; Ge, Shemin; Hickman, Stephen H.; Holland, Austin F.; Majer, Ernest; Rubinstein, Justin L.; Sheehan, Anne</p> <p>2015-01-01</p> <p>Large areas of the United States long considered geologically stable with little or no detected seismicity have recently become seismically active. The increase in <span class="hlt">earthquake</span> activity began in the mid-continent starting in 2001 (1) and has continued to rise. In 2014, the <span class="hlt">rate</span> of occurrence of <span class="hlt">earthquakes</span> with magnitudes (M) of 3 and greater in Oklahoma exceeded that in California (see the figure). This elevated activity includes larger <span class="hlt">earthquakes</span>, several with M > 5, that have caused significant damage (2, 3). To a large extent, the increasing <span class="hlt">rate</span> of <span class="hlt">earthquakes</span> in the mid-continent is due to fluid-injection activities used in modern energy production (1, 4, 5). We explore potential avenues for mitigating effects of induced seismicity. Although the United States is our focus here, Canada, China, the UK, and others confront similar problems associated with oil and gas production, whereas quakes induced by geothermal activities affect Switzerland, Germany, and others.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.G14A..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.G14A..02B"><span>Crustal strain accumulation on Southern Basin and Range Province faults modulated by distant plate boundary <span class="hlt">earthquakes</span>? Evidence from geodesy, seismic imaging, and paleoseismology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bennett, R. A.; Shirzaei, M.; Broermann, J.; Spinler, J. C.; Holland, A. A.; Pearthree, P.</p> <p>2014-12-01</p> <p> will persist relative to the <span class="hlt">recurrence</span> interval of large Salton Trough <span class="hlt">earthquakes</span>. Understanding the influence of far-field postseismic deformation on the southern Arizona strain <span class="hlt">rate</span> field could have implications for other regions of diffuse intracontinental deformation in proximity to frequently rupturing large magnitude plate boundary faults.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011NHESS..11.2235D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011NHESS..11.2235D"><span>The CATDAT damaging <span class="hlt">earthquakes</span> database</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Daniell, J. E.; Khazai, B.; Wenzel, F.; Vervaeck, A.</p> <p>2011-08-01</p> <p>The global CATDAT damaging <span class="hlt">earthquakes</span> and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture) database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic <span class="hlt">earthquakes</span>. Lack of consistency and errors in other <span class="hlt">earthquake</span> loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon. Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging <span class="hlt">earthquakes</span> historically, with over 7000 <span class="hlt">earthquakes</span> since 1900 examined and validated before insertion into the database. Each validated <span class="hlt">earthquake</span> includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected), and economic losses (direct, indirect, aid, and insured). Globally, a slightly increasing trend in economic damage due to <span class="hlt">earthquakes</span> is not consistent with the greatly increasing exposure. The 1923 Great Kanto (214 billion USD damage; 2011 HNDECI-adjusted dollars) compared to the 2011 Tohoku (>300 billion USD at time of writing), 2008 Sichuan and 1995 Kobe <span class="hlt">earthquakes</span> show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product), exchange <span class="hlt">rate</span>, wage information, population, HDI (Human Development Index), and insurance information have been collected globally to form comparisons. This catalogue is the largest known cross-checked global historic damaging <span class="hlt">earthquake</span> database and should have far-reaching consequences for <span class="hlt">earthquake</span> loss estimation, socio-economic analysis, and the global reinsurance field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S21D..03H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S21D..03H"><span>Numerical Investigation of <span class="hlt">Earthquake</span> Nucleation on a Laboratory-Scale Heterogeneous Fault with <span class="hlt">Rate</span>-and-State Friction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Higgins, N.; Lapusta, N.</p> <p>2014-12-01</p> <p>Many large <span class="hlt">earthquakes</span> on natural faults are preceded by smaller events, often termed foreshocks, that occur close in time and space to the larger event that follows. Understanding the origin of such events is important for understanding <span class="hlt">earthquake</span> physics. Unique laboratory experiments of <span class="hlt">earthquake</span> nucleation in a meter-scale slab of granite (McLaskey and Kilgore, 2013; McLaskey et al., 2014) demonstrate that sample-scale nucleation processes are also accompanied by much smaller seismic events. One potential explanation for these foreshocks is that they occur on small asperities - or bumps - on the fault interface, which may also be the locations of smaller critical nucleation size. We explore this possibility through 3D numerical simulations of a heterogeneous 2D fault embedded in a homogeneous elastic half-space, in an attempt to qualitatively reproduce the laboratory observations of foreshocks. In our model, the simulated fault interface is governed by <span class="hlt">rate</span>-and-state friction with laboratory-relevant frictional properties, fault loading, and fault size. To create favorable locations for foreshocks, the fault surface heterogeneity is represented as patches of increased normal stress, decreased characteristic slip distance L, or both. Our simulation results indicate that one can create a <span class="hlt">rate</span>-and-state model of the experimental observations. Models with a combination of higher normal stress and lower L at the patches are closest to matching the laboratory observations of foreshocks in moment magnitude, source size, and stress drop. In particular, we find that, when the local compression is increased, foreshocks can occur on patches that are smaller than theoretical critical nucleation size estimates. The additional inclusion of lower L for these patches helps to keep stress drops within the range observed in experiments, and is compatible with the asperity model of foreshock sources, since one would expect more compressed spots to be smoother (and hence have</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70189625','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70189625"><span><span class="hlt">Earthquake</span> source properties from pseudotachylite</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Beeler, Nicholas M.; Di Toro, Giulio; Nielsen, Stefan</p> <p>2016-01-01</p> <p>The motions radiated from an <span class="hlt">earthquake</span> contain information that can be interpreted as displacements within the source and therefore related to stress drop. Except in a few notable cases, the source displacements can neither be easily related to the absolute stress level or fault strength, nor attributed to a particular physical mechanism. In contrast paleo-<span class="hlt">earthquakes</span> recorded by exhumed pseudotachylite have a known dynamic mechanism whose properties constrain the co-seismic fault strength. Pseudotachylite can also be used to directly address a longstanding discrepancy between seismologically measured static stress drops, which are typically a few MPa, and much larger dynamic stress drops expected from thermal weakening during localized slip at seismic speeds in crystalline rock [Sibson, 1973; McKenzie and Brune, 1969; Lachenbruch, 1980; Mase and Smith, 1986; Rice, 2006] as have been observed recently in laboratory experiments at high slip <span class="hlt">rates</span> [Di Toro et al., 2006a]. This note places pseudotachylite-derived estimates of fault strength and inferred stress levels within the context and broader bounds of naturally observed <span class="hlt">earthquake</span> source parameters: apparent stress, stress drop, and overshoot, including consideration of roughness of the fault surface, off-fault damage, fracture energy, and the 'strength excess'. The analysis, which assumes stress drop is related to corner frequency by the Madariaga [1976] source model, is restricted to the intermediate sized <span class="hlt">earthquakes</span> of the Gole Larghe fault zone in the Italian Alps where the dynamic shear strength is well-constrained by field and laboratory measurements. We find that radiated energy exceeds the shear-generated heat and that the maximum strength excess is ~16 MPa. More generally these events have inferred <span class="hlt">earthquake</span> source parameters that are <span class="hlt">rate</span>, for instance a few percent of the global <span class="hlt">earthquake</span> population has stress drops as large, unless: fracture energy is routinely greater than existing models allow</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25654196','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25654196"><span><span class="hlt">Recurrence</span> <span class="hlt">rate</span> and patient satisfaction of CO2 laser evaporation of lesions in patients with hidradenitis suppurativa: a retrospective study.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mikkelsen, Peter Riis; Dufour, Deirde Nathalie; Zarchi, Kian; Jemec, Gregor B E</p> <p>2015-02-01</p> <p>Hidradenitis suppurativa (HS) is a debilitating disease and is difficult to treat. Validation of surgical techniques is therefore of great importance in the management of HS. Carbon dioxide (CO2) laser evaporation has been shown effective, but larger-scale studies are scarce. To determine the <span class="hlt">recurrence</span> <span class="hlt">rate</span>, time to <span class="hlt">recurrence</span>, and factors influencing disease <span class="hlt">recurrence</span> in skin treated with CO2 laser evaporation, and healing by secondary intention; and patients' satisfaction with treatment. Fifty-eight patients treated with CO2 laser evaporation were interviewed regarding <span class="hlt">recurrence</span> and satisfaction after a mean of 25.7 months. Seventeen of 58 (29%) reported <span class="hlt">recurrence</span> of HS lesions within the borders of the treated areas after a mean of 12.7 months. Obesity was a risk factor for <span class="hlt">recurrence</span> with a hazard ratio of 4.53. Fifty-five patients (95%) reported some or great improvement, and 91% would recommend the CO2 laser surgery to other HS patients. This study supports the claim that CO2 laser treatment is an effective modality for <span class="hlt">recurrent</span> HS lesions in a majority of patients. The authors identified obesity as a risk factor for <span class="hlt">recurrence</span>. Self-reported satisfaction is high, and only 3 of 58 report no change in the condition. None reported a worsening.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17789780','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17789780"><span><span class="hlt">Earthquake</span> hazards on the cascadia subduction zone.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Heaton, T H; Hartzell, S H</p> <p>1987-04-10</p> <p>Large subduction <span class="hlt">earthquakes</span> on the Cascadia subduction zone pose a potential seismic hazard. Very young oceanic lithosphere (10 million years old) is being subducted beneath North America at a <span class="hlt">rate</span> of approximately 4 centimeters per year. The Cascadia subduction zone shares many characteristics with subduction zones in southern Chile, southwestern Japan, and Colombia, where comparably young oceanic lithosphere is also subducting. Very large subduction <span class="hlt">earthquakes</span>, ranging in energy magnitude (M(w)) between 8 and 9.5, have occurred along these other subduction zones. If the Cascadia subduction zone is also storing elastic energy, a sequence of several great <span class="hlt">earthquakes</span> (M(w) 8) or a giant <span class="hlt">earthquake</span> (M(w) 9) would be necessary to fill this 1200-kilometer gap. The nature of strong ground motions recorded during subduction <span class="hlt">earthquakes</span> of M(w) less than 8.2 is discussed. Strong ground motions from even larger <span class="hlt">earthquakes</span> (M(w) up to 9.5) are estimated by simple simulations. If large subduction <span class="hlt">earthquakes</span> occur in the Pacific Northwest, relatively strong shaking can be expected over a large region. Such <span class="hlt">earthquakes</span> may also be accompanied by large local tsunamis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S23E..03H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S23E..03H"><span>An interdisciplinary approach for <span class="hlt">earthquake</span> modelling and forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Han, P.; Zhuang, J.; Hattori, K.; Ogata, Y.</p> <p>2016-12-01</p> <p><span class="hlt">Earthquake</span> is one of the most serious disasters, which may cause heavy casualties and economic losses. Especially in the past two decades, huge/mega <span class="hlt">earthquakes</span> have hit many countries. Effective <span class="hlt">earthquake</span> forecasting (including time, location, and magnitude) becomes extremely important and urgent. To date, various heuristically derived algorithms have been developed for forecasting <span class="hlt">earthquakes</span>. Generally, they can be classified into two types: catalog-based approaches and non-catalog-based approaches. Thanks to the rapid development of statistical seismology in the past 30 years, now we are able to evaluate the performances of these <span class="hlt">earthquake</span> forecast approaches quantitatively. Although a certain amount of precursory information is available in both <span class="hlt">earthquake</span> catalogs and non-catalog observations, the <span class="hlt">earthquake</span> forecast is still far from satisfactory. In most case, the precursory phenomena were studied individually. An <span class="hlt">earthquake</span> model that combines self-exciting and mutually exciting elements was developed by Ogata and Utsu from the Hawkes process. The core idea of this combined model is that the status of the event at present is controlled by the event itself (self-exciting) and all the external factors (mutually exciting) in the past. In essence, the conditional intensity function is a time-varying Poisson process with <span class="hlt">rate</span> λ(t), which is composed of the background <span class="hlt">rate</span>, the self-exciting term (the information from past seismic events), and the external excitation term (the information from past non-seismic observations). This model shows us a way to integrate the catalog-based forecast and non-catalog-based forecast. Against this background, we are trying to develop a new <span class="hlt">earthquake</span> forecast model which combines catalog-based and non-catalog-based approaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70015987','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70015987"><span>Acceleration spectra for subduction zone <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Boatwright, J.; Choy, G.L.</p> <p>1989-01-01</p> <p>We estimate the source spectra of shallow <span class="hlt">earthquakes</span> from digital recordings of teleseismic P wave groups, that is, P+pP+sP, by making frequency dependent corrections for the attenuation and for the interference of the free surface. The correction for the interference of the free surface assumes that the <span class="hlt">earthquake</span> radiates energy from a range of depths. We apply this spectral analysis to a set of 12 subduction zone <span class="hlt">earthquakes</span> which range in size from Ms = 6.2 to 8.1, obtaining corrected P wave acceleration spectra on the frequency band from 0.01 to 2.0 Hz. Seismic moment estimates from surface waves and normal modes are used to extend these P wave spectra to the frequency band from 0.001 to 0.01 Hz. The acceleration spectra of large subduction zone <span class="hlt">earthquakes</span>, that is, <span class="hlt">earthquakes</span> whose seismic moments are greater than 1027 dyn cm, exhibit intermediate slopes where u(w)???w5/4 for frequencies from 0.005 to 0.05 Hz. For these <span class="hlt">earthquakes</span>, spectral shape appears to be a discontinuous function of seismic moment. Using reasonable assumptions for the phase characteristics, we transform the spectral shape observed for large <span class="hlt">earthquakes</span> into the time domain to fit Ekstrom's (1987) moment <span class="hlt">rate</span> functions for the Ms=8.1 Michoacan <span class="hlt">earthquake</span> of September 19, 1985, and the Ms=7.6 Michoacan aftershock of September 21, 1985. -from Authors</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.8883P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.8883P"><span>An <span class="hlt">Earthquake</span> Rupture Forecast model for central Italy submitted to CSEP project</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pace, B.; Peruzza, L.</p> <p>2009-04-01</p> <p>We defined a seismogenic source model for central Italy and computed the relative forecast scenario, in order to submit the results to the CSEP (Collaboratory for the study of <span class="hlt">Earthquake</span> Predictability, www.cseptesting.org) project. The goal of CSEP project is developing a virtual, distributed laboratory that supports a wide range of scientific prediction experiments in multiple regional or global natural laboratories, and Italy is the first region in Europe for which fully prospective testing is planned. The model we propose is essentially the Layered Seismogenic Source for Central Italy (LaSS-CI) we published in 2006 (Pace et al., 2006). It is based on three different layers of sources: the first one collects the individual faults liable to generate major <span class="hlt">earthquakes</span> (M >5.5); the second layer is given by the instrumental seismicity analysis of the past two decades, which allows us to evaluate the background seismicity (M ~<5.0). The third layer utilizes all the instrumental <span class="hlt">earthquakes</span> and the historical events not correlated to known structures (4.5<M<6), by separating them into seismotectonic provinces shaped on a geological-structural basis. The second and third layers act as poissonian sources, while a simplified time-dependent hypothesis has been introduced for some individual sources, computing the conditional probability of occurrence of characteristic <span class="hlt">earthquakes</span> by Brownian passage time distribution. Beside the original model, updated <span class="hlt">earthquake</span> rupture forecasts only for individual sources are released too, in the light of recent analyses (Peruzza et al., 2008; Zoeller et al., 2008). We computed forecasts based on the LaSS-CI model for two time-windows: 5 and 10 years. Each model to be tested defines a forecasted <span class="hlt">earthquake</span> <span class="hlt">rate</span> in magnitude bins of 0.1 unit steps in the range M5-9, for the periods 1st April 2009 to 1st April 2014, and 1st April 2009 to 1st April 2019. B. Pace, L. Peruzza, G. Lavecchia, and P. Boncio (2006) Layered Seismogenic Source</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70021771','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70021771"><span>Foreshock occurrence before large <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Reasenberg, P.A.</p> <p>1999-01-01</p> <p><span class="hlt">Rates</span> of foreshock occurrence involving shallow M ??? 6 and M ??? 7 mainshocks and M ??? 5 foreshocks were measured in two worldwide catalogs over ???20-year intervals. The overall <span class="hlt">rates</span> observed are similar to ones measured in previous worldwide and regional studies when they are normalized for the ranges of magnitude difference they each span. The observed worldwide <span class="hlt">rates</span> were compared to a generic model of <span class="hlt">earthquake</span> clustering based on patterns of small and moderate aftershocks in California. The aftershock model was extended to the case of moderate foreshocks preceding large mainshocks. Overall, the observed worldwide foreshock <span class="hlt">rates</span> exceed the extended California generic model by a factor of ???2. Significant differences in foreshock <span class="hlt">rate</span> were found among subsets of <span class="hlt">earthquakes</span> defined by their focal mechanism and tectonic region, with the <span class="hlt">rate</span> before thrust events higher and the <span class="hlt">rate</span> before strike-slip events lower than the worldwide average. Among the thrust events, a large majority, composed of events located in shallow subduction zones, had a high foreshock <span class="hlt">rate</span>, while a minority, located in continental thrust belts, had a low <span class="hlt">rate</span>. These differences may explain why previous surveys have found low foreshock <span class="hlt">rates</span> among thrust events in California (especially southern California), while the worldwide observations suggests the opposite: California, lacking an active subduction zone in most of its territory, and including a region of mountain-building thrusts in the south, reflects the low <span class="hlt">rate</span> apparently typical for continental thrusts, while the worldwide observations, dominated by shallow subduction zone events, are foreshock-rich. If this is so, then the California generic model may significantly underestimate the conditional probability for a very large (M ??? 8) <span class="hlt">earthquake</span> following a potential (M ??? 7) foreshock in Cascadia. The magnitude differences among the identified foreshock-mainshock pairs in the Harvard catalog are consistent with a uniform</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70030439','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70030439"><span>Great <span class="hlt">earthquakes</span> of variable magnitude at the Cascadia subduction zone</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, A.R.; Kelsey, H.M.; Witter, R.C.</p> <p>2006-01-01</p> <p>Comparison of histories of great <span class="hlt">earthquakes</span> and accompanying tsunamis at eight coastal sites suggests plate-boundary ruptures of varying length, implying great <span class="hlt">earthquakes</span> of variable magnitude at the Cascadia subduction zone. Inference of rupture length relies on degree of overlap on radiocarbon age ranges for <span class="hlt">earthquakes</span> and tsunamis, and relative amounts of coseismic subsidence and heights of tsunamis. Written records of a tsunami in Japan provide the most conclusive evidence for rupture of much of the plate boundary during the <span class="hlt">earthquake</span> of 26 January 1700. Cascadia stratigraphic evidence dating from about 1600??cal yr B.P., similar to that for the 1700 <span class="hlt">earthquake</span>, implies a similarly long rupture with substantial subsidence and a high tsunami. Correlations are consistent with other long ruptures about 1350??cal yr B.P., 2500??cal yr B.P., 3400??cal yr B.P., 3800??cal yr B.P., 4400??cal yr B.P., and 4900??cal yr B.P. A rupture about 700-1100??cal yr B.P. was limited to the northern and central parts of the subduction zone, and a northern rupture about 2900??cal yr B.P. may have been similarly limited. Times of probable short ruptures in southern Cascadia include about 1100??cal yr B.P., 1700??cal yr B.P., 3200??cal yr B.P., 4200??cal yr B.P., 4600??cal yr B.P., and 4700??cal yr B.P. Rupture patterns suggest that the plate boundary in northern Cascadia usually breaks in long ruptures during the greatest <span class="hlt">earthquakes</span>. Ruptures in southernmost Cascadia vary in length and <span class="hlt">recurrence</span> intervals more than ruptures in northern Cascadia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70029953','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70029953"><span>Source parameters of a M4.8 and its accompanying repeating <span class="hlt">earthquakes</span> off Kamaishi, NE Japan: Implications for the hierarchical structure of asperities and <span class="hlt">earthquake</span> cycle</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Uchida, N.; Matsuzawa, T.; Ellsworth, W.L.; Imanishi, K.; Okada, T.; Hasegawa, A.</p> <p>2007-01-01</p> <p>We determine the source parameters of a M4.9 ?? 0.1 'characteristic <span class="hlt">earthquake</span>' sequence and its accompanying microearthquakes at ???50 km depth on the subduction plate boundary offshore of Kamaishi, NE Japan. The microearthquakes tend to occur more frequently in the latter half of the <span class="hlt">recurrence</span> intervals of the M4.9 ?? 0.1 events. Our results show that the microearthquakes are repeating events and they are located not only around but also within the slip area for the 2001 M4.8 event. From the hierarchical structure of slip areas and smaller stress drops for the microearthquakes compared to the M4.8 event, we infer the small repeating <span class="hlt">earthquakes</span> rupture relatively weak patches in and around the slip area for the M4.8 event and their activity reflects a stress concentration process and/or change in frictional property (healing) at the area. We also infer the patches for the M4.9 ?? 0.1 and other repeating <span class="hlt">earthquakes</span> undergo aseismic slip during their interseismic period. Copyright 2007 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27538015','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27538015"><span>Does Early Resumption of Low-Dose Aspirin After Evacuation of Chronic Subdural Hematoma With Burr-Hole Drainage Lead to Higher <span class="hlt">Recurrence</span> <span class="hlt">Rates</span>?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kamenova, Maria; Lutz, Katharina; Schaedelin, Sabine; Fandino, Javier; Mariani, Luigi; Soleman, Jehuda</p> <p>2016-11-01</p> <p>Antiplatelet therapy in patients with chronic subdural hematoma (cSDH) presents significant neurosurgical challenges. Given the lack of guidelines regarding perioperative management with antiplatelet therapy, it is difficult to balance the patient's increased cardiovascular risk and prevalence of cSDH. To better understand the risk and <span class="hlt">recurrence</span> <span class="hlt">rates</span> related to resuming low-dose acetylsalicylic acid (ASA) by evaluating our patients' resumption of low-dose ASA at various times after burr-hole drainage of the hematoma. In our retrospective study, 140 consecutive patients taking low-dose ASA undergoing surgical evacuation of cSDH were included. Data included baseline characteristics and <span class="hlt">rates</span> of <span class="hlt">recurrence</span>, morbidity, and mortality. A multivariate logistic regression model analyzed the association between ASA resumption time and <span class="hlt">recurrence</span> <span class="hlt">rates</span>. No statistically significant association was observed between early postoperative resumption of low-dose ASA and <span class="hlt">recurrence</span> of cSDH (odds ratio, 1.01; 95% confidence interval, 1.001-1.022; P = .06). Corresponding odds ratios and risk differences for restarting ASA treatment on postoperative days 1, 7, 14, 21, 28, 35, or 42 were estimated at 1.53 and 5.9%, 1.42 and 5.1%, 1.33 and 4.1%, 1.23 and 3.2%, 1.15 and 2.2%, 1.07 and 1.1%, and 1.01 and 0.2%, respectively (P > .05). Cardiovascular event <span class="hlt">rates</span>, surgical morbidity, and mortality did not significantly differ between patients with or without ASA therapy. Given the few published studies regarding ASA use in cranial neurosurgery, our findings elucidate one issue, showing comparable <span class="hlt">recurrence</span> <span class="hlt">rates</span> with early or late resumption of low-dose ASA after burr-hole evacuation of cSDH. ASA, acetylsalicylic acidCAD, coronary artery diseaseCI, confidence intervalcSDH, chronic subdural hematomaGCS, Glasgow Coma ScalemRS, modified Rankin ScaleOR, odds ratioRD, risk difference.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70036936','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70036936"><span><span class="hlt">Earthquake</span> impact scale</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wald, D.J.; Jaiswal, K.S.; Marano, K.D.; Bausch, D.</p> <p>2011-01-01</p> <p>With the advent of the USGS prompt assessment of global <span class="hlt">earthquakes</span> for response (PAGER) system, which rapidly assesses <span class="hlt">earthquake</span> impacts, U.S. and international <span class="hlt">earthquake</span> responders are reconsidering their automatic alert and activation levels and response procedures. To help facilitate rapid and appropriate <span class="hlt">earthquake</span> response, an <span class="hlt">Earthquake</span> Impact Scale (EIS) is proposed on the basis of two complementary criteria. On the basis of the estimated cost of damage, one is most suitable for domestic events; the other, on the basis of estimated ranges of fatalities, is generally more appropriate for global events, particularly in developing countries. Simple thresholds, derived from the systematic analysis of past <span class="hlt">earthquake</span> impact and associated response levels, are quite effective in communicating predicted impact and response needed after an event through alerts of green (little or no impact), yellow (regional impact and response), orange (national-scale impact and response), and red (international response). Corresponding fatality thresholds for yellow, orange, and red alert levels are 1, 100, and 1,000, respectively. For damage impact, yellow, orange, and red thresholds are triggered by estimated losses reaching $1M, $100M, and $1B, respectively. The rationale for a dual approach to <span class="hlt">earthquake</span> alerting stems from the recognition that relatively high fatalities, injuries, and homelessness predominate in countries in which local building practices typically lend themselves to high collapse and casualty <span class="hlt">rates</span>, and these impacts lend to prioritization for international response. In contrast, financial and overall societal impacts often trigger the level of response in regions or countries in which prevalent <span class="hlt">earthquake</span> resistant construction practices greatly reduce building collapse and resulting fatalities. Any newly devised alert, whether economic- or casualty-based, should be intuitive and consistent with established lexicons and procedures. Useful alerts should</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S51C0170K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S51C0170K"><span>The 2004 Parkfield, CA <span class="hlt">Earthquake</span>: A Teachable Moment for Exploring <span class="hlt">Earthquake</span> Processes, Probability, and <span class="hlt">Earthquake</span> Prediction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kafka, A.; Barnett, M.; Ebel, J.; Bellegarde, H.; Campbell, L.</p> <p>2004-12-01</p> <p>The occurrence of the 2004 Parkfield <span class="hlt">earthquake</span> provided a unique "teachable moment" for students in our science course for teacher education majors. The course uses seismology as a medium for teaching a wide variety of science topics appropriate for future teachers. The 2004 Parkfield <span class="hlt">earthquake</span> occurred just 15 minutes after our students completed a lab on <span class="hlt">earthquake</span> processes and <span class="hlt">earthquake</span> prediction. That lab included a discussion of the Parkfield <span class="hlt">Earthquake</span> Prediction Experiment as a motivation for the exercises they were working on that day. Furthermore, this <span class="hlt">earthquake</span> was recorded on an AS1 seismograph right in their lab, just minutes after the students left. About an hour after we recorded the <span class="hlt">earthquake</span>, the students were able to see their own seismogram of the event in the lecture part of the course, which provided an excellent teachable moment for a lecture/discussion on how the occurrence of the 2004 Parkfield <span class="hlt">earthquake</span> might affect seismologists' ideas about <span class="hlt">earthquake</span> prediction. The specific lab exercise that the students were working on just before we recorded this <span class="hlt">earthquake</span> was a "sliding block" experiment that simulates <span class="hlt">earthquakes</span> in the classroom. The experimental apparatus includes a flat board on top of which are blocks of wood attached to a bungee cord and a string wrapped around a hand crank. Plate motion is modeled by slowly turning the crank, and <span class="hlt">earthquakes</span> are modeled as events in which the block slips ("blockquakes"). We scaled the <span class="hlt">earthquake</span> data and the blockquake data (using how much the string moved as a proxy for time) so that we could compare blockquakes and <span class="hlt">earthquakes</span>. This provided an opportunity to use interevent-time histograms to teach about <span class="hlt">earthquake</span> processes, probability, and <span class="hlt">earthquake</span> prediction, and to compare <span class="hlt">earthquake</span> sequences with blockquake sequences. We were able to show the students, using data obtained directly from their own lab, how global <span class="hlt">earthquake</span> data fit a Poisson exponential distribution better</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.U53D0103R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.U53D0103R"><span>Widespread Triggering of <span class="hlt">Earthquakes</span> in the Central US by the 2011 M9.0 Tohoku-Oki <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rubinstein, J. L.; Savage, H. M.</p> <p>2011-12-01</p> <p>The strong shaking of the 2011 M9.0 off-Tohoku <span class="hlt">earthquake</span> triggered tectonic tremor and <span class="hlt">earthquakes</span> in many locations around the world. We analyze broadband records from the USARRAY to identify triggered seismicity in more than 10 different locations in the Central United States. We identify triggered events in many states including: Kansas, Nebraska, Arkansas, Minnesota, and Iowa. The locally triggered <span class="hlt">earthquakes</span> are obscured in broadband records by the Tohoku-Oki mainshock but can be revealed with high-pass filtering. With the exception of one location (central Arkansas), the triggered seismicity occurred in regions that are seismically quiet. The coincidence of this seismicity with the Tohoku-Oki event suggests that these <span class="hlt">earthquakes</span> were triggered. The triggered seismicity in Arkansas occurred in a region where there has been an active swarm of seismicity since August 2010. There are two lines of evidence to indicate that the seismicity in Arkansas is triggered instead of part of the swarm: (1) we observe two <span class="hlt">earthquakes</span> that initiate coincident with the arrival of shear wave and Love wave; (2) the seismicity <span class="hlt">rate</span> increased dramatically following the Tohoku-Oki mainshock. Our observations of widespread <span class="hlt">earthquake</span> triggering in regions thought to be seismically quiet remind us that <span class="hlt">earthquakes</span> can occur in most any location. Studying additional teleseismic events has the potential to reveal regions with a propensity for <span class="hlt">earthquake</span> triggering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.S53D..07F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.S53D..07F"><span>Toward a physics-based <span class="hlt">rate</span> and state friction law for <span class="hlt">earthquake</span> nucleation processes in fault zones with granular gouge</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferdowsi, B.; Rubin, A. M.</p> <p>2017-12-01</p> <p>Numerical simulations of <span class="hlt">earthquake</span> nucleation rely on constitutive <span class="hlt">rate</span> and state evolution laws to model <span class="hlt">earthquake</span> initiation and propagation processes. The response of different state evolution laws to large velocity increases is an important feature of these constitutive relations that can significantly change the style of <span class="hlt">earthquake</span> nucleation in numerical models. However, currently there is not a rigorous understanding of the physical origins of the response of bare rock or gouge-filled fault zones to large velocity increases. This in turn hinders our ability to design physics-based friction laws that can appropriately describe those responses. We here argue that most fault zones form a granular gouge after an initial shearing phase and that it is the behavior of the gouge layer that controls the fault friction. We perform numerical experiments of a confined sheared granular gouge under a range of confining stresses and driving velocities relevant to fault zones and apply 1-3 order of magnitude velocity steps to explore dynamical behavior of the system from grain- to macro-scales. We compare our numerical observations with experimental data from biaxial double-direct-shear fault gouge experiments under equivalent loading and driving conditions. Our intention is to first investigate the degree to which these numerical experiments, with Hertzian normal and Coulomb friction laws at the grain-grain contact scale and without any time-dependent plasticity, can reproduce experimental fault gouge behavior. We next compare the behavior observed in numerical experiments with predictions of the Dieterich (Aging) and Ruina (Slip) friction laws. Finally, the numerical observations at the grain and meso-scales will be used for designing a <span class="hlt">rate</span> and state evolution law that takes into account recent advances in rheology of granular systems, including local and non-local effects, for a wide range of shear <span class="hlt">rates</span> and slow and fast deformation regimes of the fault gouge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24016611','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24016611"><span>Effect of intraoperative neuromonitoring on <span class="hlt">recurrent</span> laryngeal nerve palsy <span class="hlt">rates</span> after thyroid surgery--a meta-analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zheng, Shixing; Xu, Zhiwen; Wei, Yuanyuan; Zeng, Manli; He, Jinnian</p> <p>2013-08-01</p> <p>Though intraoperative nerve monitoring (IONM) during thyroid surgery has gained universal acceptance for localizing and identifying the <span class="hlt">recurrent</span> laryngeal nerve (RLN), its role in reducing the <span class="hlt">rate</span> of RLN injury remains controversial. In order to assess the effect of IONM during thyroid surgery, its value in reducing the incidence of RLN palsy was systematically evaluated. Studies were evaluated for inclusion in this analysis by researching PubMed, Embase, the Cochrane Central Register of Controlled Trials, and the references of included studies. The initial screening of article titles and abstracts was independently performed by five reviewers based on the research protocol criteria. Each article was then read in detail and discussed before inclusion in the meta-analysis. Data were independently extracted, including the level of evidence, number of at-risk nerves, allocation method, baseline equivalence between groups, definitions of transient and permanent vocal fold palsy, systematic application of electrodes, etc. The meta-analysis was then performed. Odds ratios were pooled using a random effects model. Five randomized clinical trials and 12 comparative trials evaluating 36,487 at-risk nerves were included. Statistically significant differences in terms of total <span class="hlt">recurrent</span> laryngeal nerve palsy (3.37% with intraoperative nerve monitoring [IONM] vs. 3.76% without IONM [OR: 0.74; 95% confidence interval [CI]: 0.59-0.92]) and transient <span class="hlt">recurrent</span> laryngeal nerve palsy (2.56% with IONM vs. 2.71% without IONM [OR: 0.80; 95% CI: 0.65-0.99]) were identified. The persistent incidence of <span class="hlt">recurrent</span> laryngeal nerve palsy was 0.78% for IONM versus 0.96% for nerve identification alone (OR: 0.80; 95% CI: 0.62-1.03). Based on this meta-analysis, statistically significant differences were determined in terms of the incidences of total and transient <span class="hlt">recurrent</span> laryngeal nerve palsy after using IONM versus <span class="hlt">recurrent</span> laryngeal nerve identification alone during thyroidectomy</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S43D..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S43D..08M"><span>Measuring Aseismic Slip through Characteristically Repeating <span class="hlt">Earthquakes</span> at the Mendocino Triple Junction, Northern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Materna, K.; Taira, T.; Burgmann, R.</p> <p>2016-12-01</p> <p>The Mendocino Triple Junction (MTJ), at the transition point between the San Andreas fault system, the Mendocino Transform Fault, and the Cascadia Subduction Zone, undergoes rapid tectonic deformation and produces more large (M>6.0) <span class="hlt">earthquakes</span> than any region in California. Most of the active faults of the triple junction are located offshore, making it difficult to characterize both seismic slip and aseismic creep. In this work, we study aseismic creep <span class="hlt">rates</span> near the MTJ using characteristically repeating <span class="hlt">earthquakes</span> (CREs) as indicators of creep <span class="hlt">rate</span>. CREs are generally interpreted as repeated failures of the same seismic patch within an otherwise creeping fault zone; as a consequence, the magnitude and <span class="hlt">recurrence</span> time of the CREs can be used to determine a fault's creep <span class="hlt">rate</span> through empirically calibrated scaling relations. Using seismic data from 2010-2016, we identify CREs as recorded by an array of eight 100-Hz PBO borehole seismometers deployed in the Cape Mendocino area. For each event pair with epicenters less than 30 km apart, we compute the cross-spectral coherence of 20 seconds of data starting one second before the P-wave arrival. We then select pairs with high coherence in an appropriate frequency band, which is determined uniquely for each event pair based on event magnitude, station distance, and signal-to-noise ratio. The most similar events (with median coherence above 0.95 at two or more stations) are selected as CREs and then grouped into CRE families, and each family is used to infer a local creep <span class="hlt">rate</span>. On the Mendocino Transform Fault, we find relatively high creep <span class="hlt">rates</span> of >5 cm/year that increase closer to the Gorda Ridge. Closer to shore and to the MTJ itself, we find many families of repeaters on and off the transform fault with highly variable creep <span class="hlt">rates</span>, indicative of the complex deformation that takes place there.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20433639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20433639"><span>Single-nucleotide polymorphisms and mRNA expression for melatonin synthesis <span class="hlt">rate</span>-limiting enzyme in <span class="hlt">recurrent</span> depressive disorder.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gałecki, Piotr; Szemraj, Janusz; Bartosz, Grzegorz; Bieńkiewicz, Małgorzata; Gałecka, Elzbieta; Florkowski, Antoni; Lewiński, Andrzej; Karbownik-Lewińska, Małgorzata</p> <p>2010-05-01</p> <p>Depressive disorder (DD) is characterised by disturbances in blood melatonin concentration. It is well known that melatonin is involved in the control of circadian rhythms, sleep included. The use of melatonin and its analogues has been found to be effective in depression therapy. Melatonin synthesis is a multistage process, where the last stage is catalysed by acetylserotonin methyltransferase (ASMT), the reported <span class="hlt">rate</span>-limiting melatonin synthesis enzyme. Taking into account the significance of genetic factors in depression development, the gene for ASMT may become an interesting focus for studies in patients with <span class="hlt">recurrent</span> DD. The goal of the study was to evaluate two single-nucleotide polymorphisms (SNPs) (rs4446909; rs5989681) of the ASMT gene, as well as mRNA expression for ASMT in <span class="hlt">recurrent</span> DD-affected patients. We genotyped two polymorphisms in a group of 181 <span class="hlt">recurrent</span> DD patients and in 149 control subjects. The study was performed using the polymerase chain reaction/restriction fragment length polymorphism method. The distribution of genotypes in both studied SNPs in the ASMT gene differed significantly between DD and healthy subjects. The presence of AA genotype of rs4446909 polymorphism and of GG genotype of rs5989681 polymorphism was associated with lower risk for having <span class="hlt">recurrent</span> DD. In turn, patients with depression were characterised by reduced mRNA expression for ASMT. In addition, ASMT transcript level in both <span class="hlt">recurrent</span> DD patients and in healthy subjects depended significantly on genotype distributions in both polymorphisms. In conclusion, our results suggest the ASMT gene as a susceptibility gene for <span class="hlt">recurrent</span> DD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S34A..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S34A..02M"><span>The Mechanics of Transient Fault Slip and Slow <span class="hlt">Earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marone, C.; Leeman, J.; Scuderi, M.; Saffer, D. M.; Collettini, C.</p> <p>2015-12-01</p> <p><span class="hlt">Earthquakes</span> are understood as frictional stick-slip instabilities in which stored elastic energy is released suddenly, driving catastrophic failure. In normal (fast) <span class="hlt">earthquakes</span> the rupture zone expands at a <span class="hlt">rate</span> dictated by elastic wave speeds, a few km/s, and fault slip <span class="hlt">rates</span> reach 1-10 m/s. However, tectonic faults also fail in slow <span class="hlt">earthquakes</span> with rupture durations of months and fault slip speeds of ~100 micron/s or less. We know very little about the mechanics of slow <span class="hlt">earthquakes</span>. What determines the rupture propagation velocity in slow <span class="hlt">earthquakes</span> and in other forms of quasi-dynamic rupture? What processes limit stress drop and fault slip speed in slow <span class="hlt">earthquakes</span>? Existing lab studies provide some help via observations of complex forms of stick-slip, creep-slip, or, in a few cases, slow slip. However, these are mainly anecdotal and rarely include examples of repetitive slow slip or systematic measurements that could be used to isolate the underlying mechanisms. Numerical studies based on <span class="hlt">rate</span> and state friction also shed light on transiently accelerating slip, showing that slow slip can occur if: 1) fault rheology involves a change in friction <span class="hlt">rate</span> dependence (a-b) with velocity or unusually large values of the frictional weakening distance Dc, or 2) fault zone elastic stiffness equals the critical frictional weakening <span class="hlt">rate</span> kc = (b-a)/Dc. Recent laboratory work shows that the latter can occur much more commonly that previously thought. We document the complete spectrum of stick-slip behaviors from transient slow slip to fast stick-slip for a narrow range of conditions around k/kc = 1.0. Slow slip occurs near the threshold between stable and unstable failure, controlled by the interplay of fault zone frictional properties, normal stress, and elastic stiffness of the surrounding rock. Our results provide a generic mechanism for slow <span class="hlt">earthquakes</span>, consistent with the wide range of conditions for which slow slip has been observed.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004GeoJI.159..931C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004GeoJI.159..931C"><span>New constraints on the rupture process of the 1999 August 17 Izmit <span class="hlt">earthquake</span> deduced from estimates of stress glut <span class="hlt">rate</span> moments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clévédé, E.; Bouin, M.-P.; Bukchin, B.; Mostinskiy, A.; Patau, G.</p> <p>2004-12-01</p> <p>This paper illustrates the use of integral estimates given by the stress glut <span class="hlt">rate</span> moments of total degree 2 for constraining the rupture scenario of a large <span class="hlt">earthquake</span> in the particular case of the 1999 Izmit mainshock. We determine the integral estimates of the geometry, source duration and rupture propagation given by the stress glut <span class="hlt">rate</span> moments of total degree 2 by inverting long-period surface wave (LPSW) amplitude spectra. Kinematic and static models of the Izmit <span class="hlt">earthquake</span> published in the literature are quite different from one another. In order to extract the characteristic features of this event, we calculate the same integral estimates directly from those models and compare them with those deduced from our inversion. While the equivalent rupture zone and the eastward directivity are consistent among all models, the LPSW solution displays a strong unilateral character of the rupture associated with a short rupture duration that is not compatible with the solutions deduced from the published models. With the aim of understand this discrepancy, we use simple equivalent kinematic models to reproduce the integral estimates of the considered rupture processes (including ours) by adjusting a few free parameters controlling the western and eastern parts of the rupture. We show that the joint analysis of the LPSW solution and source tomographies allows us to elucidate the scattering of source processes published for this <span class="hlt">earthquake</span> and to discriminate between the models. Our results strongly suggest that (1) there was significant moment released on the eastern segment of the activated fault system during the Izmit <span class="hlt">earthquake</span>; (2) the apparent rupture velocity decreases on this segment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3515557','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3515557"><span>Faith after an <span class="hlt">Earthquake</span>: A Longitudinal Study of Religion and Perceived Health before and after the 2011 Christchurch New Zealand <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Sibley, Chris G.; Bulbulia, Joseph</p> <p>2012-01-01</p> <p>On 22 February 2011, Christchurch New Zealand (population 367,700) experienced a devastating <span class="hlt">earthquake</span>, causing extensive damage and killing one hundred and eighty-five people. The <span class="hlt">earthquake</span> and aftershocks occurred between the 2009 and 2011 waves of a longitudinal probability sample conducted in New Zealand, enabling us to examine how a natural disaster of this magnitude affected deeply held commitments and global <span class="hlt">ratings</span> of personal health, depending on <span class="hlt">earthquake</span> exposure. We first investigated whether the <span class="hlt">earthquake</span>-affected were more likely to believe in God. Consistent with the Religious Comfort Hypothesis, religious faith increased among the <span class="hlt">earthquake</span>-affected, despite an overall decline in religious faith elsewhere. This result offers the first population-level demonstration that secular people turn to religion at times of natural crisis. We then examined whether religious affiliation was associated with differences in subjective <span class="hlt">ratings</span> of personal health. We found no evidence for superior buffering from having religious faith. Among those affected by the <span class="hlt">earthquake</span>, however, a loss of faith was associated with significant subjective health declines. Those who lost faith elsewhere in the country did not experience similar health declines. Our findings suggest that religious conversion after a natural disaster is unlikely to improve subjective well-being, yet upholding faith might be an important step on the road to recovery. PMID:23227147</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25273900','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25273900"><span>Evidence for ASD <span class="hlt">recurrence</span> <span class="hlt">rates</span> and reproductive stoppage from large UK ASD research family databases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wood, Claire L; Warnell, Frances; Johnson, Mary; Hames, Annette; Pearce, Mark S; McConachie, Helen; Parr, Jeremy R</p> <p>2015-02-01</p> <p>Following a diagnosis of a developmental disorder such as autism spectrum disorder (ASD) in early childhood, parents may decide to have fewer children than previously planned. The tendency for families to halt reproduction after receiving a diagnosis for one child is known as reproductive stoppage. Stoppage may lead to an underestimate of <span class="hlt">recurrence</span> risk estimates of parents having more than one child with ASD. Using two large UK ASD family databases, we investigated <span class="hlt">recurrence</span> <span class="hlt">rates</span> for ASD and evidence for reproductive stoppage for both ASD and undiagnosed ASD/broader autism phenotype in a subgroup of families. Reproductive stoppage was tested for using the Mann-Whitney U-test to disprove the null hypothesis that affected and nonaffected children were distributed randomly by birth order. Dahlberg's later-sib method was used to estimate <span class="hlt">recurrence</span> risk and take stoppage into account. Data were available from 299 families (660 children) including 327 with ASD. Ten percent of the complete families had more than one child with an ASD. Using Dahlberg's later-sib method, the <span class="hlt">recurrence</span> risk for ASD was 24.7% overall and 50.0% in families with two or more older siblings with ASD. Children with ASD were born significantly later in families than those without ASD in all sibship combinations. This study shows strong evidence that ASD is associated with reproductive stoppage. These data have important implications for family planning and genetic counseling. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22771402','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22771402"><span>Management and <span class="hlt">recurrence</span> of keratocystic odontogenic tumor: a systematic review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Johnson, Nigel R; Batstone, Martin D; Savage, Neil W</p> <p>2013-10-01</p> <p>The objective of this study was to evaluate the most up-to-date treatment modalities and respective <span class="hlt">recurrence</span> <span class="hlt">rates</span> for keratocystic odontogenic tumor (KCOT). A systematic review of the literature from 1999 to 2010 was undertaken examining treatment and <span class="hlt">recurrence</span> <span class="hlt">rates</span> for KCOT. Four inclusion criteria were defined for articles to then be analyzed against 8 standards. Of the 2736 published articles, 8 met the inclusion criteria. When merging the data, enucleation and enucleation with adjunctive measures (other than Carnoy's solution) had <span class="hlt">recurrence</span> <span class="hlt">rates</span> of 25.6% and 30.3%, respectively. Marsupialization with adjunctive measures produced a <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 15.8%, whereas enucleation with Carnoy's solution presented a <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 7.9%. Only one resection case had <span class="hlt">recurrence</span> (6.3%). The enucleation technique with the use of adjunctive procedures (other than Carnoy's solution) provides a higher <span class="hlt">recurrence</span> <span class="hlt">rate</span> than any other treatment modality. Copyright © 2013 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004EP%26S...56..773O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004EP%26S...56..773O"><span><span class="hlt">Earthquake</span> cycles and physical modeling of the process leading up to a large <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ohnaka, Mitiyasu</p> <p>2004-08-01</p> <p>A thorough discussion is made on what the rational constitutive law for <span class="hlt">earthquake</span> ruptures ought to be from the standpoint of the physics of rock friction and fracture on the basis of solid facts observed in the laboratory. From this standpoint, it is concluded that the constitutive law should be a slip-dependent law with parameters that may depend on slip <span class="hlt">rate</span> or time. With the long-term goal of establishing a rational methodology of forecasting large <span class="hlt">earthquakes</span>, the entire process of one cycle for a typical, large <span class="hlt">earthquake</span> is modeled, and a comprehensive scenario that unifies individual models for intermediate-and short-term (immediate) forecasts is presented within the framework based on the slip-dependent constitutive law and the <span class="hlt">earthquake</span> cycle model. The <span class="hlt">earthquake</span> cycle includes the phase of accumulation of elastic strain energy with tectonic loading (phase II), and the phase of rupture nucleation at the critical stage where an adequate amount of the elastic strain energy has been stored (phase III). Phase II plays a critical role in physical modeling of intermediate-term forecasting, and phase III in physical modeling of short-term (immediate) forecasting. The seismogenic layer and individual faults therein are inhomogeneous, and some of the physical quantities inherent in <span class="hlt">earthquake</span> ruptures exhibit scale-dependence. It is therefore critically important to incorporate the properties of inhomogeneity and physical scaling, in order to construct realistic, unified scenarios with predictive capability. The scenario presented may be significant and useful as a necessary first step for establishing the methodology for forecasting large <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T31D2946W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T31D2946W"><span>The Cause of the Cauca, Colombia, Cluster of Intermediate-Depth <span class="hlt">Earthquakes</span> From <span class="hlt">Earthquake</span> Relocation and Focal Mechanisms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Warren, L. M.; Chang, Y.; Prieto, G. A.</p> <p>2016-12-01</p> <p>In subducting slabs, a high seismicity <span class="hlt">rate</span> in a concentrated volume (an <span class="hlt">earthquake</span> cluster) is often associated with geometric complexities such as slab detachment, tearing, or contortions. The intermediate-depth Cauca, Colombia, cluster (3.5°N-5.5°N), in contrast, appears to be located in a slab without such complexities. However, previous constraints on the slab geometry are based on global data. We use regional data to investigate the cause of the Cauca cluster by estimating its geometry from <span class="hlt">earthquake</span> relocations and stress regime from focal mechanism calculations and stress inversions. The Cauca segment of the Nazca Plate is characterized by relatively sparse seismicity away from the cluster and a narrow volcanic arc. To the northeast of the Cauca cluster, six active volcanoes are concentrated within an 80-km along-trench distance and are isolated 180 km from the rest of the northern Andes volcanic arc. The Colombian National Seismic Network, from Jan 2010 to Mar 2014, reports 433 <span class="hlt">earthquakes</span> in the cluster at depths of 50-200 km with local magnitudes ranging from 2.0-4.7. <span class="hlt">Earthquake</span> relocations show a continuous 20-km-thick seismic zone dipping at 33°-43°, with the angle increasing to the south. In addition, <span class="hlt">earthquakes</span> locate in two columns that extend normal to the slab and into the mantle wedge. The focal mechanisms show various types, including down-dip extension, strike slip, and trench-parallel compression, but are consistent with a predominantly down-dip extensional stress field. The maximum and intermediate stress axes are interchangeable because of their similar magnitudes. The down-dip extensional stress regime may expel dehydrated fluid from the slab into the mantle wedge. As the fluid moves through the mantle wedge, it may generate hydrofractures and the observed mantle-wedge <span class="hlt">earthquakes</span>. The fluid in the mantle wedge may be transported along the trench, from the steeper southern section to the more shallowly-dipping northern section, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/earthquakes.html','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/earthquakes.html"><span><span class="hlt">Earthquakes</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>An <span class="hlt">earthquake</span> happens when two blocks of the earth suddenly slip past one another. <span class="hlt">Earthquakes</span> strike suddenly, violently, and without warning at any time of the day or night. If an <span class="hlt">earthquake</span> occurs in a populated area, it may cause ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70190041','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70190041"><span>Updating the USGS seismic hazard maps for Alaska</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Mueller, Charles; Briggs, Richard; Wesson, Robert L.; Petersen, Mark D.</p> <p>2015-01-01</p> <p>The U.S. Geological Survey makes probabilistic seismic hazard maps and engineering design maps for building codes, emergency planning, risk management, and many other applications. The methodology considers all known <span class="hlt">earthquake</span> sources with their associated magnitude and <span class="hlt">rate</span> distributions. Specific faults can be modeled if slip-<span class="hlt">rate</span> or <span class="hlt">recurrence</span> information is available. Otherwise, areal sources are developed from <span class="hlt">earthquake</span> catalogs or GPS data. Sources are combined with ground-motion estimates to compute the hazard. The current maps for Alaska were developed in 2007, and included modeled sources for the Alaska-Aleutian megathrust, a few crustal faults, and areal seismicity sources. The megathrust was modeled as a segmented dipping plane with segmentation largely derived from the slip patches of past <span class="hlt">earthquakes</span>. Some megathrust deformation is aseismic, so <span class="hlt">recurrence</span> was estimated from seismic history rather than plate <span class="hlt">rates</span>. Crustal faults included the Fairweather-Queen Charlotte system, the Denali–Totschunda system, the Castle Mountain fault, two faults on Kodiak Island, and the Transition fault, with <span class="hlt">recurrence</span> estimated from geologic data. Areal seismicity sources were developed for Benioff-zone <span class="hlt">earthquakes</span> and for crustal <span class="hlt">earthquakes</span> not associated with modeled faults. We review the current state of knowledge in Alaska from a seismic-hazard perspective, in anticipation of future updates of the maps. Updated source models will consider revised seismicity catalogs, new information on crustal faults, new GPS data, and new thinking on megathrust <span class="hlt">recurrence</span>, segmentation, and geometry. Revised ground-motion models will provide up-to-date shaking estimates for crustal <span class="hlt">earthquakes</span> and subduction <span class="hlt">earthquakes</span> in Alaska.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.G53A0765L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.G53A0765L"><span>GPS-derived Coseismic deformations of the 2016 Aktao Ms6.7 <span class="hlt">earthquake</span> and source modelling</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Li, J.; Zhao, B.; Xiaoqiang, W.; Daiqing, L.; Yushan, A.</p> <p>2017-12-01</p> <p>On 25th November 2016, a Ms6.7 <span class="hlt">earthquake</span> occurred on Aktao, a county of Xinjiang, China. This <span class="hlt">earthquake</span> was the largest <span class="hlt">earthquake</span> occurred in the northeastern margin of the Pamir Plateau in the last 30 years. By GPS observation, we get the coseismic displacement of this <span class="hlt">earthquake</span>. The maximum displacement site is located in the Muji Basin, 15km from south of the causative fault. The maximum deformation is down to 0.12m, and 0.10m for coseismic displacement, our results indicate that the <span class="hlt">earthquake</span> has the characteristics of dextral strike-slip and normal-fault rupture. Based on the GPS results, we inverse the rupture distribution of the <span class="hlt">earthquake</span>. The source model is consisted of two approximate independent zones with a depth of less than 20km, the maximum displacement of one zone is 0.6m, the other is 0.4m. The total seismic moment is Mw6.6.1 which is calculated by the geodetic inversion. The source model of GPS-derived is basically consistent with that of seismic waveform inversion, and is consistent with the surface rupture distribution obtained from field investigation. According to our inversion calculation, the <span class="hlt">recurrence</span> period of strong <span class="hlt">earthquakes</span> similar to this <span class="hlt">earthquake</span> should be 30 60 years, and the seismic risk of the eastern segment of Muji fault is worthy of attention. This research is financially supported by National Natural Science Foundation of China (Grant No.41374030)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70034496','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70034496"><span>First Results of the Regional <span class="hlt">Earthquake</span> Likelihood Models Experiment</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Schorlemmer, D.; Zechar, J.D.; Werner, M.J.; Field, E.H.; Jackson, D.D.; Jordan, T.H.</p> <p>2010-01-01</p> <p>The ability to successfully predict the future behavior of a system is a strong indication that the system is well understood. Certainly many details of the <span class="hlt">earthquake</span> system remain obscure, but several hypotheses related to <span class="hlt">earthquake</span> occurrence and seismic hazard have been proffered, and predicting <span class="hlt">earthquake</span> behavior is a worthy goal and demanded by society. Along these lines, one of the primary objectives of the Regional <span class="hlt">Earthquake</span> Likelihood Models (RELM) working group was to formalize <span class="hlt">earthquake</span> occurrence hypotheses in the form of prospective <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecasts in California. RELM members, working in small research groups, developed more than a dozen 5-year forecasts; they also outlined a performance evaluation method and provided a conceptual description of a Testing Center in which to perform predictability experiments. Subsequently, researchers working within the Collaboratory for the Study of <span class="hlt">Earthquake</span> Predictability (CSEP) have begun implementing Testing Centers in different locations worldwide, and the RELM predictability experiment-a truly prospective <span class="hlt">earthquake</span> prediction effort-is underway within the U. S. branch of CSEP. The experiment, designed to compare time-invariant 5-year <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecasts, is now approximately halfway to its completion. In this paper, we describe the models under evaluation and present, for the first time, preliminary results of this unique experiment. While these results are preliminary-the forecasts were meant for an application of 5 years-we find interesting results: most of the models are consistent with the observation and one model forecasts the distribution of <span class="hlt">earthquakes</span> best. We discuss the observed sample of target <span class="hlt">earthquakes</span> in the context of historical seismicity within the testing region, highlight potential pitfalls of the current tests, and suggest plans for future revisions to experiments such as this one. ?? 2010 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PApGe.167..859S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PApGe.167..859S"><span>First Results of the Regional <span class="hlt">Earthquake</span> Likelihood Models Experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schorlemmer, Danijel; Zechar, J. Douglas; Werner, Maximilian J.; Field, Edward H.; Jackson, David D.; Jordan, Thomas H.</p> <p>2010-08-01</p> <p>The ability to successfully predict the future behavior of a system is a strong indication that the system is well understood. Certainly many details of the <span class="hlt">earthquake</span> system remain obscure, but several hypotheses related to <span class="hlt">earthquake</span> occurrence and seismic hazard have been proffered, and predicting <span class="hlt">earthquake</span> behavior is a worthy goal and demanded by society. Along these lines, one of the primary objectives of the Regional <span class="hlt">Earthquake</span> Likelihood Models (RELM) working group was to formalize <span class="hlt">earthquake</span> occurrence hypotheses in the form of prospective <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecasts in California. RELM members, working in small research groups, developed more than a dozen 5-year forecasts; they also outlined a performance evaluation method and provided a conceptual description of a Testing Center in which to perform predictability experiments. Subsequently, researchers working within the Collaboratory for the Study of <span class="hlt">Earthquake</span> Predictability (CSEP) have begun implementing Testing Centers in different locations worldwide, and the RELM predictability experiment—a truly prospective <span class="hlt">earthquake</span> prediction effort—is underway within the U.S. branch of CSEP. The experiment, designed to compare time-invariant 5-year <span class="hlt">earthquake</span> <span class="hlt">rate</span> forecasts, is now approximately halfway to its completion. In this paper, we describe the models under evaluation and present, for the first time, preliminary results of this unique experiment. While these results are preliminary—the forecasts were meant for an application of 5 years—we find interesting results: most of the models are consistent with the observation and one model forecasts the distribution of <span class="hlt">earthquakes</span> best. We discuss the observed sample of target <span class="hlt">earthquakes</span> in the context of historical seismicity within the testing region, highlight potential pitfalls of the current tests, and suggest plans for future revisions to experiments such as this one.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018JGRB..123..583B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018JGRB..123..583B"><span>Constraints on Friction, Dilatancy, Diffusivity, and Effective Stress From Low-Frequency <span class="hlt">Earthquake</span> <span class="hlt">Rates</span> on the Deep San Andreas Fault</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beeler, N. M.; Thomas, Amanda; Bürgmann, Roland; Shelly, David</p> <p>2018-01-01</p> <p>Families of recurring low-frequency <span class="hlt">earthquakes</span> (LFEs) within nonvolcanic tremor on the San Andreas Fault in central California are sensitive to tidal stresses. LFEs occur at all levels of the tides, are strongly correlated and in phase with the 200 Pa shear stresses, and weakly and not systematically correlated with the 2 kPa tidal normal stresses. We assume that LFEs are small sources that repeatedly fail during shear within a much larger scale, aseismically slipping fault zone and consider two different models of the fault slip: (1) modulation of the fault slip <span class="hlt">rate</span> by the tidal stresses or (2) episodic slip, triggered by the tides. LFEs are strongly clustered with duration much shorter than the semidiurnal tide; they cannot be significantly modulated on that time scale. The <span class="hlt">recurrence</span> times of clusters, however, are many times longer than the semidiurnal, leading to an appearance of tidal triggering. In this context we examine the predictions of laboratory-observed triggered frictional (dilatant) fault slip. The undrained end-member model produces no sensitivity to the tidal normal stress, and slip onsets are in phase with the tidal shear stress. The tidal correlation constrains the diffusivity to be less than 1 × 10-6/s and the product of the friction and dilatancy coefficients to be at most 5 × 10-7, orders of magnitude smaller than observed at room temperature. In the absence of dilatancy the effective normal stress at failure would be about 55 kPa. For this model the observations require intrinsic weakness, low dilatancy, and lithostatic pore fluid.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2018GeoRL..45.3059I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2018GeoRL..45.3059I"><span>Seismic Moment, Seismic Energy, and Source Duration of Slow <span class="hlt">Earthquakes</span>: Application of Brownian slow <span class="hlt">earthquake</span> model to three major subduction zones</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ide, Satoshi; Maury, Julie</p> <p>2018-04-01</p> <p>Tectonic tremors, low-frequency <span class="hlt">earthquakes</span>, very low-frequency <span class="hlt">earthquakes</span>, and slow slip events are all regarded as components of broadband slow <span class="hlt">earthquakes</span>, which can be modeled as a stochastic process using Brownian motion. Here we show that the Brownian slow <span class="hlt">earthquake</span> model provides theoretical relationships among the seismic moment, seismic energy, and source duration of slow <span class="hlt">earthquakes</span> and that this model explains various estimates of these quantities in three major subduction zones: Japan, Cascadia, and Mexico. While the estimates for these three regions are similar at the seismological frequencies, the seismic moment <span class="hlt">rates</span> are significantly different in the geodetic observation. This difference is ascribed to the difference in the characteristic times of the Brownian slow <span class="hlt">earthquake</span> model, which is controlled by the width of the source area. We also show that the model can include non-Gaussian fluctuations, which better explains recent findings of a near-constant source duration for low-frequency <span class="hlt">earthquake</span> families.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730019521','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730019521"><span>ERTS Applications in <span class="hlt">earthquake</span> research and mineral exploration in California</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Abdel-Gawad, M.; Silverstein, J.</p> <p>1973-01-01</p> <p>Examples that ERTS imagery can be effectively utilized to identify, locate, and map faults which show geomorphic evidence of geologically recent breakage are presented. Several important faults not previously known have been identified. By plotting epicenters of historic <span class="hlt">earthquakes</span> in parts of California, Sonora, Mexico, Arizona, and Nevada, we found that areas known for historic seismicity are often characterized by abundant evidence of recent fault and crustal movements. There are many examples of seismically quiet areas where outstanding evidence of recent fault movements is observed. One application is clear: ERTS-1 imagery could be effectively utilized to delineate areas susceptible to <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> which, on the basis of seismic data alone, may be misleadingly considered safe. ERTS data can also be utilized in planning new sites in the geophysical network of fault movement monitoring and strain and tilt measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815317D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815317D"><span>Bayesian exploration of recent Chilean <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duputel, Zacharie; Jiang, Junle; Jolivet, Romain; Simons, Mark; Rivera, Luis; Ampuero, Jean-Paul; Liang, Cunren; Agram, Piyush; Owen, Susan; Ortega, Francisco; Minson, Sarah</p> <p>2016-04-01</p> <p>The South-American subduction zone is an exceptional natural laboratory for investigating the behavior of large faults over the <span class="hlt">earthquake</span> cycle. It is also a playground to develop novel modeling techniques combining different datasets. Coastal Chile was impacted by two major <span class="hlt">earthquakes</span> in the last two years: the 2015 M 8.3 Illapel <span class="hlt">earthquake</span> in central Chile and the 2014 M 8.1 Iquique <span class="hlt">earthquake</span> that ruptured the central portion of the 1877 seismic gap in northern Chile. To gain better understanding of the distribution of co-seismic slip for those two <span class="hlt">earthquakes</span>, we derive joint kinematic finite fault models using a combination of static GPS offsets, radar interferograms, tsunami measurements, high-<span class="hlt">rate</span> GPS waveforms and strong motion data. Our modeling approach follows a Bayesian formulation devoid of a priori smoothing thereby allowing us to maximize spatial resolution of the inferred family of models. The adopted approach also attempts to account for major sources of uncertainty in the Green's functions. The results reveal different rupture behaviors for the 2014 Iquique and 2015 Illapel <span class="hlt">earthquakes</span>. The 2014 Iquique <span class="hlt">earthquake</span> involved a sharp slip zone and did not rupture to the trench. The 2015 Illapel <span class="hlt">earthquake</span> nucleated close to the coast and propagated toward the trench with significant slip apparently reaching the trench or at least very close to the trench. At the inherent resolution of our models, we also present the relationship of co-seismic models to the spatial distribution of foreshocks, aftershocks and fault coupling models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014NatGe...7..292M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014NatGe...7..292M"><span>Locking of the Chile subduction zone controlled by fluid pressure before the 2010 <span class="hlt">earthquake</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moreno, Marcos; Haberland, Christian; Oncken, Onno; Rietbrock, Andreas; Angiboust, Samuel; Heidbach, Oliver</p> <p>2014-04-01</p> <p>Constraints on the potential size and <span class="hlt">recurrence</span> time of strong subduction-zone <span class="hlt">earthquakes</span> come from the degree of locking between the down-going and overriding plates, in the period between large <span class="hlt">earthquakes</span>. In many cases, this interseismic locking degree correlates with slip during large <span class="hlt">earthquakes</span> or is attributed to variations in fluid content at the plate interface. Here we use geodetic and seismological data to explore the links between pore-fluid pressure and locking patterns at the subduction interface ruptured during the magnitude 8.8 Chile <span class="hlt">earthquake</span> in 2010. High-resolution three-dimensional seismic tomography reveals variations in the ratio of seismic P- to S-wave velocities (Vp/Vs) along the length of the subduction-zone interface. High Vp/Vs domains, interpreted as zones of elevated pore-fluid pressure, correlate spatially with parts of the plate interface that are poorly locked and slip aseismically. In contrast, low Vp/Vs domains, interpreted as zones of lower pore-fluid pressure, correlate with locked parts of the plate interface, where unstable slip and <span class="hlt">earthquakes</span> occur. Variations in pore-fluid pressure are caused by the subduction and dehydration of a hydrothermally altered oceanic fracture zone. We conclude that variations in pore-fluid pressure at the plate interface control the degree of interseismic locking and therefore the slip distribution of large <span class="hlt">earthquake</span> ruptures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.3873C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.3873C"><span>The integration of stress, strain, and seismogenic fault data: towards more robust estimates of the <span class="hlt">earthquake</span> potential in Italy and its surroundings</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Caporali, Alessandro; Braitenberg, Carla; Burrato, Pierfrancesco; Carafa, Michele; Di Giovambattista, Rita; Gentili, Stefania; Mariucci, Maria Teresa; Montone, Paola; Morsut, Federico; Nicolini, Luca; Pivetta, Tommaso; Roselli, Pamela; Rossi, Giuliana; Valensise, Gian Luca; Vigano, Alfio</p> <p>2016-04-01</p> <p>Italy is an <span class="hlt">earthquake</span>-prone country with a long tradition in observational seismology. For many years, the country's unique historical <span class="hlt">earthquake</span> record has revealed fundamental properties of Italian seismicity and has been used to determine <span class="hlt">earthquake</span> <span class="hlt">rates</span>. Paleoseismological studies conducted over the past 20 years have shown that the length of this record - 5 to 8 centuries, depending on areas - is just a fraction of the typical <span class="hlt">recurrence</span> interval of Italian faults - consistently larger than a millennium. Hence, so far the <span class="hlt">earthquake</span> potential may have been significantly over- or under-estimated. Based on a clear perception of these circumstances, over the past two decades large networks and datasets describing independent aspects of the seismic cycle have been developed. INGV, OGS, some universities and local administrations have built networks that globally include nearly 500 permanent GPS/GNSS sites, routinely used to compute accurate horizontal velocity gradients reflecting the accumulation of tectonic strain. INGV developed the Italian present-day stress map, which includes over 700 datapoints based on geophysical in-situ measurements and fault plane solutions, and the Database of Individual Seismogenic Sources (DISS), a unique compilation featuring nearly 300 three-dimensional seismogenic faults over the entire nation. INGV also updates and maintains the Catalogo Parametrico dei Terremoti Italiani (CPTI) and the instrumental <span class="hlt">earthquake</span> database ISIDe, whereas OGS operates its own seismic catalogue for northeastern Italy. We present preliminary results on the use of this wealth of homogeneously collected and updated observations of stress and strain as a source of loading/unloading of the faults listed in the DISS database. We use the geodetic strain <span class="hlt">rate</span> - after converting it to stress <span class="hlt">rate</span> in conjunction with the geophysical stress data of the Stress Map - to compute the Coulomb Failure Function on all fault planes described by the DISS database. This</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.2030J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.2030J"><span>Combination of High <span class="hlt">Rate</span>, Real-time GNSS and Accelerometer Observations - Preliminary Results Using a Shake Table and Historic <span class="hlt">Earthquake</span> Events.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jackson, Michael; Passmore, Paul; Zimakov, Leonid; Raczka, Jared</p> <p>2014-05-01</p> <p>One of the fundamental requirements of an <span class="hlt">Earthquake</span> Early Warning (EEW) system (and other mission critical applications) is to quickly detect and process the information from the strong motion event, i.e. event detection and location, magnitude estimation, and the peak ground motion estimation at the defined targeted site, thus allowing the civil protection authorities to provide pre-programmed emergency response actions: Slow down or stop rapid transit trains and high-speed trains; shutoff of gas pipelines and chemical facilities; stop elevators at the nearest floor; send alarms to hospitals, schools and other civil institutions. An important question associated with the EEW system is: can we measure displacements in real time with sufficient accuracy? Scientific GNSS networks are moving towards a model of real-time data acquisition, storage integrity, and real-time position and displacement calculations. This new paradigm allows the integration of real-time, high-<span class="hlt">rate</span> GNSS displacement information with acceleration and velocity data to create very high-<span class="hlt">rate</span> displacement records. The mating of these two instruments allows the creation of a new, very high-<span class="hlt">rate</span> (200 Hz) displacement observable that has the full-scale displacement characteristics of GNSS and high-precision dynamic motions of seismic technologies. It is envisioned that these new observables can be used for <span class="hlt">earthquake</span> early warning studies and other mission critical applications, such as volcano monitoring, building, bridge and dam monitoring systems. REF TEK a Division of Trimble has developed the integrated GNSS/Accelerograph system, model 160-09SG, which consists of REF TEK's fourth generation electronics, a 147-01 high-resolution ANSS Class A accelerometer, and Trimble GNSS receiver and antenna capable of real time, on board Precise Point Positioning (PPP) techniques with satellite clock and orbit corrections delivered to the receiver directly via L-band satellite communications. The test we</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70031442','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70031442"><span>Near-fault peak ground velocity from <span class="hlt">earthquake</span> and laboratory data</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>McGarr, A.; Fletcher, Joe B.</p> <p>2007-01-01</p> <p>We test the hypothesis that peak ground velocity (PGV) has an upper bound independent of <span class="hlt">earthquake</span> magnitude and that this bound is controlled primarily by the strength of the seismogenic crust. The highest PGVs, ranging up to several meters per second, have been measured at sites within a few kilometers of the causative faults. Because the database for near-fault PGV is small, we use <span class="hlt">earthquake</span> slip models, laboratory experiments, and evidence from a mining-induced <span class="hlt">earthquake</span> to investigate the factors influencing near-fault PGV and the nature of its scaling. For each <span class="hlt">earthquake</span> slip model we have calculated the peak slip <span class="hlt">rates</span> for all subfaults and then chosen the maximum of these <span class="hlt">rates</span> as an estimate of twice the largest near-fault PGV. Nine slip models for eight <span class="hlt">earthquakes</span>, with magnitudes ranging from 6.5 to 7.6, yielded maximum peak slip <span class="hlt">rates</span> ranging from 2.3 to 12 m/sec with a median of 5.9 m/sec. By making several adjustments, PGVs for small <span class="hlt">earthquakes</span> can be simulated from peak slip <span class="hlt">rates</span> measured during laboratory stick-slip experiments. First, we adjust the PGV for differences in the state of stress (i.e., the difference between the laboratory loading stresses and those appropriate for faults at seismogenic depths). To do this, we multiply both the slip and the peak slip <span class="hlt">rate</span> by the ratio of the effective normal stresses acting on fault planes measured at 6.8 km depth at the KTB site, Germany (deepest available in situ stress measurements), to those acting on the laboratory faults. We also adjust the seismic moment by replacing the laboratory fault with a buried circular shear crack whose radius is chosen to match the experimental unloading stiffness. An additional, less important adjustment is needed for experiments run in triaxial loading conditions. With these adjustments, peak slip <span class="hlt">rates</span> for 10 stick-slip events, with scaled moment magnitudes from -2.9 to 1.0, range from 3.3 to 10.3 m/sec, with a median of 5.4 m/sec. Both the <span class="hlt">earthquake</span> and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26880644','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26880644"><span>Autism: Will vitamin D supplementation during pregnancy and early childhood reduce the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of autism in newborn siblings?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Stubbs, G; Henley, K; Green, J</p> <p>2016-03-01</p> <p>Vitamin D deficiency is widespread in the world including the vulnerable group of pregnant women. Vitamin D deficiency during pregnancy is hypothesized to contribute to the cause of autism. Further, it is hypothesized that vitamin D supplementation during pregnancy and early childhood will reduce the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of autism in newborn siblings. To investigate the hypothesis an open label prospective study was performed prescribing vitamin D during pregnancy to mothers of children with autism at a dose of 5000IU/day. The newborn siblings were at high risk for the <span class="hlt">recurrence</span> of autism. The newborn infants were also prescribed vitamin D, 1000IU/day to their third birthday. The newborn siblings were followed for three years and during that time, were assessed for autism on two separate occasions: at 18months and 36months of age. The results were compared to the reported <span class="hlt">recurrence</span> <span class="hlt">rates</span> in siblings of autistic children in the literature. The final outcome was 1 out of 19 (5%) developed autism in contrast to the <span class="hlt">recurrence</span> <span class="hlt">rate</span> of approximately 20% in the literature. We did not have a control group, nor was there blinding. The results are promising, however, this is a preliminary study with very small numbers and was uncontrolled. Further study with larger numbers is indicated. The ethics of prescribing a low dosage of vitamin D such as 400IU D3/day to a control group of mothers in comparison to a large dose such as 5000IU D3/day are problematic in our opinion. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..MAR.M1161M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..MAR.M1161M"><span>Man-made <span class="hlt">Earthquakes</span> & Multifractals in Neutral Fluid Turbulence/Injection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maksoed, Wh-</p> <p></p> <p>Man-made <span class="hlt">earthquakes</span> coincides with induced seismicity:''typically minor <span class="hlt">earthquakes</span> & tremors that are caused by human activity that alters the stresses & Strains on the earth crust''[Wikipedia:''induced seismicity'']. For these, RD Andrews wrote:''Based on observed seismicity <span class="hlt">rate</span> &geographical trends following major oil & gas plays with large amounts of produced water, the <span class="hlt">rates</span> &trends in seismicity are very unlikely to represent a naturally occurring process''. ``The Prague, Oklahoma, <span class="hlt">earthquake</span> sequence of 2011, along the Wilzetta faults zone, included the significant foreshock, a main shock of magnetic 5.7, it has been suggested that this sequence represent <span class="hlt">earthquakes</span> triggered by fluid injection/natural fluid turbulence shows multifractal characteristics , of [405 ]-325-7968 of Dr. G. Randy Keller to UI tuitions of @ Rp. 29, 405, 000.00. Acknowledgements to HE. Mr. H. TUK SETYOHADI, Jl. Sriwijaya Raya 3, South-Jakarta, INDONESIA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2012/1043/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2012/1043/"><span>Deep-Sea Turbidites as Guides to Holocene <span class="hlt">Earthquake</span> History at the Cascadia Subduction Zone—Alternative Views for a Seismic-Hazard Workshop</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Atwater, Brian F.; Griggs, Gary B.</p> <p>2012-01-01</p> <p> confluence, instead of representing the merged flows from two tributaries, monitor the dominant tributary only. Sandy beds low in the turbidites, instead of matching from channel to channel, permit divergent stratigraphic correlations; and rather than approximating strong-motion seismograms, the sandy beds more likely record processes internal to the generation and transformation of subaqueous mass movements. The age adjustments, instead of supporting other evidence that all the northern ruptures were long, are uncertain enough to accord with variation in rupture mode, and this variation improves agreement with onshore paleoseismology. Many of the turbidites counted as evidence for frequent <span class="hlt">earthquakes</span> on the southern Cascadia plate boundary may instead reflect nearness to steep slopes. This report is meant to aid in the updating of national maps of seismic hazards in Canada and the United States. It offers three main conclusions for consideration at a U.S. hazard-map workshop slated for March 21-22, 2012: If giant <span class="hlt">earthquakes</span> are the norm for the plate boundary offshore southern Washington, the strongest paleoseismic evidence for this rupture mode is the average <span class="hlt">earthquake-recurrence</span> interval of about 500 years that is evidenced both offshore in lower Cascadia Channel and onshore at estuaries of southern Washington and northernmost Oregon. The plate boundary offshore southern British Columbia and northern Washington may be capable of producing great <span class="hlt">earthquakes</span> at an average interval as short as 300 years that is evidenced mainly onshore. Review of more of the turbidite evidence now in press may clarify implications for the hazard maps. Further work on the deep-sea turbidites could target sedimentary processes and chronological uncertainties that may affect the turbidites' sensitivity to fault-rupture lengths and <span class="hlt">recurrence</span> <span class="hlt">rates</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640601','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4640601"><span>Oklahoma’s recent <span class="hlt">earthquakes</span> and saltwater disposal</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Walsh, F. Rall; Zoback, Mark D.</p> <p>2015-01-01</p> <p>Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized <span class="hlt">earthquakes</span>. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the <span class="hlt">rates</span> of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent <span class="hlt">earthquakes</span>. In the areas of seismic activity, the saltwater disposal principally comes from “produced” water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the <span class="hlt">earthquakes</span> are occurring. Although most of the recent <span class="hlt">earthquakes</span> have posed little danger to the public, the possibility of triggering damaging <span class="hlt">earthquakes</span> on potentially active basement faults cannot be discounted. PMID:26601200</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S21C..08J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S21C..08J"><span>Prospective Tests of Southern California <span class="hlt">Earthquake</span> Forecasts</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jackson, D. D.; Schorlemmer, D.; Gerstenberger, M.; Kagan, Y. Y.; Helmstetter, A.; Wiemer, S.; Field, N.</p> <p>2004-12-01</p> <p>We are testing <span class="hlt">earthquake</span> forecast models prospectively using likelihood ratios. Several investigators have developed such models as part of the Southern California <span class="hlt">Earthquake</span> Center's project called Regional <span class="hlt">Earthquake</span> Likelihood Models (RELM). Various models are based on fault geometry and slip <span class="hlt">rates</span>, seismicity, geodetic strain, and stress interactions. Here we describe the testing procedure and present preliminary results. Forecasts are expressed as the yearly <span class="hlt">rate</span> of <span class="hlt">earthquakes</span> within pre-specified bins of longitude, latitude, magnitude, and focal mechanism parameters. We test models against each other in pairs, which requires that both forecasts in a pair be defined over the same set of bins. For this reason we specify a standard "menu" of bins and ground rules to guide forecasters in using common descriptions. One menu category includes five-year forecasts of magnitude 5.0 and larger. Contributors will be requested to submit forecasts in the form of a vector of yearly <span class="hlt">earthquake</span> <span class="hlt">rates</span> on a 0.1 degree grid at the beginning of the test. Focal mechanism forecasts, when available, are also archived and used in the tests. Interim progress will be evaluated yearly, but final conclusions would be made on the basis of cumulative five-year performance. The second category includes forecasts of <span class="hlt">earthquakes</span> above magnitude 4.0 on a 0.1 degree grid, evaluated and renewed daily. Final evaluation would be based on cumulative performance over five years. Other types of forecasts with different magnitude, space, and time sampling are welcome and will be tested against other models with shared characteristics. Tests are based on the log likelihood scores derived from the probability that future <span class="hlt">earthquakes</span> would occur where they do if a given forecast were true [Kagan and Jackson, J. Geophys. Res.,100, 3,943-3,959, 1995]. For each pair of forecasts, we compute alpha, the probability that the first would be wrongly rejected in favor of the second, and beta, the probability</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/29274197','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/29274197"><span>Increased <span class="hlt">recurrence</span> <span class="hlt">rates</span> of hepatocellular carcinoma after DAA therapy in a hepatitis C-infected Egyptian cohort: A comparative analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>El Kassas, M; Funk, A L; Salaheldin, M; Shimakawa, Y; Eltabbakh, M; Jean, K; El Tahan, A; Sweedy, A T; Afify, S; Youssef, N F; Esmat, G; Fontanet, A</p> <p>2018-06-01</p> <p>In Egypt, hepatocellular carcinoma (HCC) is the most common form of cancer and direct-acting antivirals (DAA) are administered on a large scale to patients with chronic HCV infection to reduce the risk. In this unique setting, we aimed to determine the association of DAA exposure with early-phase HCC <span class="hlt">recurrence</span> in patients with a history of HCV-related liver cancer. This was a prospective cohort study of an HCV-infected population from one Egyptian specialized HCC management centre starting from the time of successful HCC intervention. The incidence <span class="hlt">rates</span> of HCC <span class="hlt">recurrence</span> between DAA-exposed and nonexposed patients were compared, starting from date of HCC complete radiological response and censoring after 2 years. DAA exposure was treated as time varying. Two Poisson regressions models were used to control for potential differences in the exposed and nonexposed group; multivariable adjustment and balancing using inverse probability of treatment weighting (IPTW). We included 116 patients: 53 treated with DAAs and 63 not treated with DAAs. There was 37.7% and 25.4% <span class="hlt">recurrence</span> in each group after a median of 16.0 and 23.0 months of follow-up, respectively. Poisson regression using IPTW demonstrated an association between DAAs and HCC <span class="hlt">recurrence</span> with an incidence <span class="hlt">rate</span> ratio of 3.83 (95% CI: 2.02-7.25), which was similar in the multivariable-adjusted model and various sensitivity analyses. These results add important evidence towards the possible role of DAAs in HCC <span class="hlt">recurrence</span> and stress the need for further mechanistic studies and clinical trials to accurately confirm this role and to identify patient characteristics that may be associated with this event. © 2017 John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.er.usgs.gov/publication/70191595','USGSPUBS'); return false;" href="https://pubs.er.usgs.gov/publication/70191595"><span>Holocene <span class="hlt">earthquakes</span> of magnitude 7 during westward escape of the Olympic Mountains, Washington</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Nelson, Alan R.; Personius, Stephen; Wells, Ray; Schermer, Elizabeth R.; Bradley, Lee-Ann; Buck, Jason; Reitman, Nadine G.</p> <p>2017-01-01</p> <p>The Lake Creek–Boundary Creek fault, previously mapped in Miocene bedrock as an oblique thrust on the north flank of the Olympic Mountains, poses a significant <span class="hlt">earthquake</span> hazard. Mapping using 2015 light detection and ranging (lidar) confirms 2004 lidar mapping of postglacial (<13  ka"><13  ka) and Holocene fault scarps along the 22‐km‐long eastern section of the fault and documents Holocene scarps that extend ≥14  km">≥14  km along a splay fault, the Sadie Creek fault, west of Lake Crescent. Scarp morphology suggests repeated <span class="hlt">earthquake</span> ruptures along the eastern section of the Lake Creek–Boundary Creek fault and the Sadie Creek fault since ∼13  ka">∼13  ka. Right‐lateral (∼11–28  m">∼11–28  m) and vertical (1–2 m) cumulative fault offsets suggest slip <span class="hlt">rates</span> of ∼1–2  mm/yr">∼1–2  mm/yr Stratigraphic and age‐model data from five trenches perpendicular to scarps at four sites on the eastern section of the fault show evidence of 3–5 surface‐rupturing <span class="hlt">earthquakes</span>. Near‐vertical fault dips and upward‐branching fault patterns in trenches, abrupt changes in the thickness of stratigraphic units across faults, and variations in vertical displacement of successive stratigraphic units along fault traces also suggest a large lateral component of slip. Age models suggest two <span class="hlt">earthquakes</span> date from 1.3±0.8">1.3±0.8 and 2.9±0.6  ka">2.9±0.6  ka; evidence and ages for 2–3 earlier <span class="hlt">earthquakes</span> are less certain. Assuming 3–5 postglacial <span class="hlt">earthquakes</span>, lateral and vertical cumulative fault offsets yield average slip per <span class="hlt">earthquake</span> of ∼4.6  m">∼4.6  m, a lateral‐to‐vertical slip ratio of ∼10:1">∼10:1, and a <span class="hlt">recurrence</span> interval of 3.5±1.0  ka">3.5±1.0  ka. Empirical relations yield moment magnitude estimates of M 7.2–7.5 (slip per <span class="hlt">earthquake</span>) and 7.1–7.3 (56 km maximum rupture length). An apparent left‐lateral Miocene to right</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19222495','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19222495"><span>Coexistence of chronic lymphocytic thyroiditis is associated with lower <span class="hlt">recurrence</span> <span class="hlt">rates</span> in patients with papillary thyroid carcinoma.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Eui Young; Kim, Won Gu; Kim, Won Bae; Kim, Tae Yong; Kim, Jung Min; Ryu, Jin-Sook; Hong, Suck Joon; Gong, Gyungyub; Shong, Young Kee</p> <p>2009-10-01</p> <p>The effect of coexistent chronic lymphocytic thyroiditis (CLT) on prognosis in papillary thyroid carcinoma (PTC) patients remains controversial. We evaluated the influence of coexistent CLT on prognostic outcome and the association of coexistent CLT with clinicopathological parameters. A retrospective study with a median follow-up of 70 months. Patients with PTC who underwent total thyroidectomy followed by (131)I remnant ablation between 1995 and 2003 at Asan Medical Center, Seoul, Korea were enrolled. CLT was diagnosed histopathologically. Among 1441 patients, 214 (14.9%) had coexistent CLT. A greater female preponderance was noted in the patients with CLT compared with those without CLT (P < 0.01). Mean tumour size in the patients with CLT was smaller than that in patients without CLT (2.0 +/- 1.2 vs. 2.2 +/- 1.4 cm; P = 0.02). One hundred and fifty-one (12.3%) patients without CLT had <span class="hlt">recurrence</span>, whereas 14 (7.1%) patients with CLT had <span class="hlt">recurrence</span> during the follow-up period (P = 0.016). In patients with cervical lymph node metastases, those with coexistent CLT showed a significantly lower <span class="hlt">recurrence</span> <span class="hlt">rate</span> than those without CLT (P = 0.012). However, this association was lost on multivariate analysis adjusting for other clinicopathological predictors for <span class="hlt">recurrence</span>. In this study, CLT was commonly associated with PTC and was associated with smaller size of the primary tumour at presentation. CLT was also associated with a reduced risk of <span class="hlt">recurrence</span> during follow-up, although this was not significant after adjustment for other prognostic factors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27720162','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27720162"><span>Is subclinical hypothyroidism associated with lower live birth <span class="hlt">rates</span> in women who have experienced unexplained <span class="hlt">recurrent</span> miscarriage?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>van Dijk, Myrthe M; Vissenberg, Rosa; Bisschop, Peter H; Dawood, Feroza; van Wely, Madelon; Goddijn, Mariëtte; Farquharson, Roy G</p> <p>2016-12-01</p> <p>Thyroid disorders have been associated with <span class="hlt">recurrent</span> miscarriage. Little evidence is available on the influence of subclinical hypothyroidism on live birth <span class="hlt">rates</span>. In this cohort study, women who had experienced miscarriage and subclinical hypothyroidism (defined as thyroid-stimulating hormone >97.5th percentile mU/l with a normal thyroxine level) were investigated; the control group included women who had experienced <span class="hlt">recurrent</span> miscarriage and normal thyroid function. Multivariable logistic regression was used to investigate the association of subclinical hypothyroidism. Data were available for 848 women; 20 (2.4%) had subclinical hypothyroidism; 818 women (96%) had euthyroidism; and 10 (1.2%) had overt hypothyroidism. The live birth <span class="hlt">rate</span> was 45% in women with subclinical hypothyroidism and 52% in euthyroid women (OR 0.69, 95% CI 0.28 to 1.71). The ongoing pregnancy <span class="hlt">rate</span> was 65% versus 69% (OR 0.82, 95% CI 0.32 to 2.10) and the miscarriage <span class="hlt">rate</span> was 35% versus 28% (OR 1.43, 95% CI 0.56 to 3.68), respectively. No differences were found when thyroid stimulating hormone 2.5 mU/l was used as cut-off level to define subclinical hypothyroidism. In women with unexplained miscarriage, no differences were found in live birth, ongoing pregnancy and miscarriage <span class="hlt">rates</span> between women with subclinical hypothyroidism and euthyroid women. Copyright © 2016. Published by Elsevier Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18330934','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18330934"><span>H pylori <span class="hlt">recurrence</span> after successful eradication.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Niv, Yaron</p> <p>2008-03-14</p> <p><span class="hlt">Recurrence</span> of H pylori after eradication is rare in developed countries and more frequent in developing countries. Recrudescence (recolonization of the same strain within 12 mo after eradication) rather than reinfection (colonization with a new strain, more than 12 mo after eradication) is considered to be responsible for most of the cases. This observation was confirmed only in developed countries, while in developing countries a recent meta-analysis demonstrated a high <span class="hlt">rate</span> of reinfection. The proportion of H pylori annual <span class="hlt">recurrence</span> was 2.67% and 13.00% in developed and developing countries, respectively. Nested meta-analysis (only cases with a longer follow-up and a negative (13)CUBT a year after eradication) revealed annual <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 1.45% [relative risk (RR), 0.54] and 12.00% (RR, 0.92) in developed and developing countries, respectively. These findings support the notion that in developed countries many cases of <span class="hlt">recurrence</span> are due to recrudescence within the first year after eradication, with a 46% drop in the <span class="hlt">recurrence</span> <span class="hlt">rate</span> after the first year post eradication, while in developing countries reinfection is more pronounced, and continue at the same <span class="hlt">rate</span> since eradication. A different approach for follow-up after H pylori eradication is probably needed in patients of developing countries, since reinfection is highly prevalent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2693738','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2693738"><span>H pylori <span class="hlt">recurrence</span> after successful eradication</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Niv, Yaron</p> <p>2008-01-01</p> <p><span class="hlt">Recurrence</span> of H pylori after eradication is rare in developed countries and more frequent in developing countries. Recrudescence (recolonization of the same strain within 12 mo after eradication) rather than reinfection (colonization with a new strain, more than 12 mo after eradication) is considered to be responsible for most of the cases. This observation was confirmed only in developed countries, while in developing countries a recent meta-analysis demonstrated a high <span class="hlt">rate</span> of reinfection. The proportion of H pylori annual <span class="hlt">recurrence</span> was 2.67% and 13.00% in developed and developing countries, respectively. Nested meta-analysis (only cases with a longer follow-up and a negative 13CUBT a year after eradication) revealed annual <span class="hlt">recurrence</span> <span class="hlt">rate</span> of 1.45% [relative risk (RR), 0.54] and 12.00% (RR, 0.92) in developed and developing countries, respectively. These findings support the notion that in developed countries many cases of <span class="hlt">recurrence</span> are due to recrudescence within the first year after eradication, with a 46% drop in the <span class="hlt">recurrence</span> <span class="hlt">rate</span> after the first year post eradication, while in developing countries reinfection is more pronounced, and continue at the same <span class="hlt">rate</span> since eradication. A different approach for follow-up after H pylori eradication is probably needed in patients of developing countries, since reinfection is highly prevalent. PMID:18330934</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.S14B..07B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.S14B..07B"><span>The 1868 Hayward <span class="hlt">Earthquake</span> Alliance: A Case Study - Using an <span class="hlt">Earthquake</span> Anniversary to Promote <span class="hlt">Earthquake</span> Preparedness</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brocher, T. M.; Garcia, S.; Aagaard, B. T.; Boatwright, J. J.; Dawson, T.; Hellweg, M.; Knudsen, K. L.; Perkins, J.; Schwartz, D. P.; Stoffer, P. W.; Zoback, M.</p> <p>2008-12-01</p> <p>Last October 21st marked the 140th anniversary of the M6.8 1868 Hayward <span class="hlt">Earthquake</span>, the last damaging <span class="hlt">earthquake</span> on the southern Hayward Fault. This anniversary was used to help publicize the seismic hazards associated with the fault because: (1) the past five such <span class="hlt">earthquakes</span> on the Hayward Fault occurred about 140 years apart on average, and (2) the Hayward-Rodgers Creek Fault system is the most likely (with a 31 percent probability) fault in the Bay Area to produce a M6.7 or greater <span class="hlt">earthquake</span> in the next 30 years. To promote <span class="hlt">earthquake</span> awareness and preparedness, over 140 public and private agencies and companies and many individual joined the public-private nonprofit 1868 Hayward <span class="hlt">Earthquake</span> Alliance (1868alliance.org). The Alliance sponsored many activities including a public commemoration at Mission San Jose in Fremont, which survived the 1868 <span class="hlt">earthquake</span>. This event was followed by an <span class="hlt">earthquake</span> drill at Bay Area schools involving more than 70,000 students. The anniversary prompted the Silver Sentinel, an <span class="hlt">earthquake</span> response exercise based on the scenario of an <span class="hlt">earthquake</span> on the Hayward Fault conducted by Bay Area County Offices of Emergency Services. 60 other public and private agencies also participated in this exercise. The California Seismic Safety Commission and KPIX (CBS affiliate) produced professional videos designed forschool classrooms promoting Drop, Cover, and Hold On. Starting in October 2007, the Alliance and the U.S. Geological Survey held a sequence of press conferences to announce the release of new research on the Hayward Fault as well as new loss estimates for a Hayward Fault <span class="hlt">earthquake</span>. These included: (1) a ShakeMap for the 1868 Hayward <span class="hlt">earthquake</span>, (2) a report by the U. S. Bureau of Labor Statistics forecasting the number of employees, employers, and wages predicted to be within areas most strongly shaken by a Hayward Fault <span class="hlt">earthquake</span>, (3) new estimates of the losses associated with a Hayward Fault <span class="hlt">earthquake</span>, (4) new ground motion</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AGUFM.T13E..07C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AGUFM.T13E..07C"><span>Controls of repeating <span class="hlt">earthquakes</span>' location from a- and b- values imaging</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, K. H.; Kawamura, M.</p> <p>2017-12-01</p> <p>The locations where creeping and locked fault areas abut have commonly found to be delineated by the foci of small repeating <span class="hlt">earthquakes</span> (REs). REs not only represent the finer structure of high creep-<span class="hlt">rate</span> location, they also function as fault slip-<span class="hlt">rate</span> indicators. Knowledge of the expected location of REs therefore, is crucial for fault deformation monitoring and assessment of <span class="hlt">earthquake</span> potential. However, a precise description of factors determining REs locations is lacking. To explore where <span class="hlt">earthquakes</span> tend to recur, we statistically investigated repeating <span class="hlt">earthquake</span> catalogs and background seismicity from different regions including six fault segments in California and Taiwan. We show that the location of repeating <span class="hlt">earthquakes</span> can be mapped using the spatial distribution of the seismic a- and b-values obtained from the background seismicity. Molchan's error diagram statistically confirmed that repeating <span class="hlt">earthquakes</span> occur within areas with high a-values (2.8-3.8) and high b-values (0.9-1.1) on both strike-slip and thrust fault segments. However, no significant association held true for fault segments with more complicated geometry or for wider areas with a complex fault network. The productivity of small <span class="hlt">earthquakes</span> responsible for high a- and b-values may thus be the most important factor controlling the location of repeating <span class="hlt">earthquakes</span>. We hypothesize that, given that the deformation conditions within a fault zone are suitable for a planar fault plane, the location of repeating <span class="hlt">earthquakes</span> can be best described by a-value 3 and b-value 1. This feature of a- and b-values may be useful for foresee the location of REs for measuring creep <span class="hlt">rate</span> at depth. Further investigation of REs-rich areas may allow testing of this hypothesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title10-vol2/pdf/CFR-2010-title10-vol2-sec72-103.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title10-vol2/pdf/CFR-2010-title10-vol2-sec72-103.pdf"><span>10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-01-01</p> <p>..., and that are not in areas of known seismic activity, a standardized design <span class="hlt">earthquake</span> ground motion... motion, tectonic surface deformation, nontectonic deformation, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault... of the Design <span class="hlt">Earthquake</span> Ground Motion (DE). The DE for the site is characterized by both horizontal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title10-vol2/pdf/CFR-2011-title10-vol2-sec72-103.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title10-vol2/pdf/CFR-2011-title10-vol2-sec72-103.pdf"><span>10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-01-01</p> <p>..., and that are not in areas of known seismic activity, a standardized design <span class="hlt">earthquake</span> ground motion... motion, tectonic surface deformation, nontectonic deformation, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault... of the Design <span class="hlt">Earthquake</span> Ground Motion (DE). The DE for the site is characterized by both horizontal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title10-vol2/pdf/CFR-2013-title10-vol2-sec72-103.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title10-vol2/pdf/CFR-2013-title10-vol2-sec72-103.pdf"><span>10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-01-01</p> <p>..., and that are not in areas of known seismic activity, a standardized design <span class="hlt">earthquake</span> ground motion... motion, tectonic surface deformation, nontectonic deformation, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault... of the Design <span class="hlt">Earthquake</span> Ground Motion (DE). The DE for the site is characterized by both horizontal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title10-vol2/pdf/CFR-2014-title10-vol2-sec72-103.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title10-vol2/pdf/CFR-2014-title10-vol2-sec72-103.pdf"><span>10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-01-01</p> <p>..., and that are not in areas of known seismic activity, a standardized design <span class="hlt">earthquake</span> ground motion... motion, tectonic surface deformation, nontectonic deformation, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault... of the Design <span class="hlt">Earthquake</span> Ground Motion (DE). The DE for the site is characterized by both horizontal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title10-vol2/pdf/CFR-2012-title10-vol2-sec72-103.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title10-vol2/pdf/CFR-2012-title10-vol2-sec72-103.pdf"><span>10 CFR 72.103 - Geological and seismological characteristics for applications for dry cask modes of storage on or...</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-01-01</p> <p>..., and that are not in areas of known seismic activity, a standardized design <span class="hlt">earthquake</span> ground motion... motion, tectonic surface deformation, nontectonic deformation, <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> <span class="hlt">rates</span>, fault... of the Design <span class="hlt">Earthquake</span> Ground Motion (DE). The DE for the site is characterized by both horizontal...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S13C..03B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S13C..03B"><span>Global <span class="hlt">Earthquake</span> Activity <span class="hlt">Rate</span> models based on version 2 of the Global Strain <span class="hlt">Rate</span> Map</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bird, P.; Kreemer, C.; Kagan, Y. Y.; Jackson, D. D.</p> <p>2013-12-01</p> <p>Global <span class="hlt">Earthquake</span> Activity <span class="hlt">Rate</span> (GEAR) models have usually been based on either relative tectonic motion (fault slip <span class="hlt">rates</span> and/or distributed strain <span class="hlt">rates</span>), or on smoothing of seismic catalogs. However, a hybrid approach appears to perform better than either parent, at least in some retrospective tests. First, we construct a Tectonic ('T') forecast of shallow (≤ 70 km) seismicity based on global plate-boundary strain <span class="hlt">rates</span> from version 2 of the Global Strain <span class="hlt">Rate</span> Map. Our approach is the SHIFT (Seismic Hazard Inferred From Tectonics) method described by Bird et al. [2010, SRL], in which the character of the strain <span class="hlt">rate</span> tensor (thrusting and/or strike-slip and/or normal) is used to select the most comparable type of plate boundary for calibration of the coupled seismogenic lithosphere thickness and corner magnitude. One difference is that activity of offshore plate boundaries is spatially smoothed using empirical half-widths [Bird & Kagan, 2004, BSSA] before conversion to seismicity. Another is that the velocity-dependence of coupling in subduction and continental-convergent boundaries [Bird et al., 2009, BSSA] is incorporated. Another forecast component is the smoothed-seismicity ('S') forecast model of [Kagan & Jackson, 1994, JGR; Kagan & Jackson, 2010, GJI], which was based on optimized smoothing of the shallow part of the GCMT catalog, years 1977-2004. Both forecasts were prepared for threshold magnitude 5.767. Then, we create hybrid forecasts by one of 3 methods: (a) taking the greater of S or T; (b) simple weighted-average of S and T; or (c) log of the forecast <span class="hlt">rate</span> is a weighted average of the logs of S and T. In methods (b) and (c) there is one free parameter, which is the fractional contribution from S. All hybrid forecasts are normalized to the same global <span class="hlt">rate</span>. Pseudo-prospective tests for 2005-2012 (using versions of S and T calibrated on years 1977-2004) show that many hybrid models outperform both parents (S and T), and that the optimal weight on S</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JSeis..20..733R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JSeis..20..733R"><span>Liquefaction record of the great 1934 <span class="hlt">earthquake</span> predecessors from the north Bihar alluvial plains of India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rajendran, C. P.; John, Biju; Rajendran, Kusala; Sanwal, Jaishri</p> <p>2016-07-01</p> <p>The great 1934 Himalayan <span class="hlt">earthquake</span> of moment magnitude (Mw) 8.1 generated a large zone of ground failure and liquefaction in north Bihar, India, in addition to the <span class="hlt">earthquakes</span> of 1833 (Mw ~7.7) and 1988 (Mw 6.7) that have also impacted this region. Here, we present the results of paleoliquefaction investigations from four sites in the plains of north Bihar and one in eastern Uttar Pradesh. The liquefaction features generated by successive <span class="hlt">earthquakes</span> were dated at AD 829-971, 886-1090, 907-1181, 1130-1376, 1112-1572, 1492-1672, 1733-1839, and 1814-1854. One of the liquefaction events dated at AD 829-971, 886-1090, and 907-1181 may correlate with the great <span class="hlt">earthquake</span> of AD ~1100, recognized in an earlier study from the sections across the frontal thrust in central eastern Nepal. Two late medieval liquefaction episodes of AD 1130-1376 and 1492-1672 were also exposed in our sites. The sedimentary sections also revealed sandblows that can be attributed to the 1833 <span class="hlt">earthquake</span>, a lesser magnitude event compared to the 1934. Liquefactions triggered by the 1934 and 1988 <span class="hlt">earthquakes</span> were evident within the topmost level in some sections. The available data lead us to conjecture that a series of temporally close spaced <span class="hlt">earthquakes</span> of both strong and large types, not including the infrequent great <span class="hlt">earthquakes</span> like the 1934, have affected the Bihar Plains during the last 1500 years with a combined <span class="hlt">recurrence</span> interval of 124 ± 63 years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Geomo.282..150P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Geomo.282..150P"><span>A morphologic proxy for debris flow erosion with application to the <span class="hlt">earthquake</span> deformation cycle, Cascadia Subduction Zone, USA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Penserini, Brian D.; Roering, Joshua J.; Streig, Ashley</p> <p>2017-04-01</p> <p>In unglaciated steeplands, valley reaches dominated by debris flow scour and incision set landscape form as they often account for > 80% of valley network length and relief. While hillslope and fluvial process models have frequently been combined with digital topography to develop morphologic proxies for erosion <span class="hlt">rate</span> and drainage divide migration, debris-flow-dominated networks, despite their ubiquity, have not been exploited for this purpose. Here, we applied an empirical function that describes how slope-area data systematically deviate from so-called fluvial power-law behavior at small drainage areas. Using airborne LiDAR data for 83 small ( 1 km2) catchments in the western Oregon Coast Range, we quantified variation in model parameters and observed that the curvature of the power-law scaling deviation varies with catchment-averaged erosion <span class="hlt">rate</span> estimated from cosmogenic nuclides in stream sediments. Given consistent climate and lithology across our study area and assuming steady erosion, we used this calibrated denudation-morphology relationship to map spatial patterns of long-term uplift for our study catchments. By combining our predicted pattern of long-term uplift <span class="hlt">rate</span> with paleoseismic and geodetic (tide gauge, GPS, and leveling) data, we estimated the spatial distribution of coseismic subsidence experienced during megathrust <span class="hlt">earthquakes</span> along the Cascadia Subduction Zone. Our estimates of coseismic subsidence near the coast (0.4 to 0.7 m for <span class="hlt">earthquake</span> <span class="hlt">recurrence</span> intervals of 300 to 500 years) agree with field measurements from numerous stratigraphic studies. Our results also demonstrate that coseismic subsidence decreases inland to negligible values > 25 km from the coast, reflecting the diminishing influence of the <span class="hlt">earthquake</span> deformation cycle on vertical changes of the interior coastal ranges. More generally, our results demonstrate that debris flow valley networks serve as highly localized, yet broadly distributed indicators of erosion (and rock</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <div class="footer-extlink text-muted" style="margin-bottom:1rem; text-align:center;">Some links on this page may take you to non-federal websites. 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