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Sample records for nonconservative earthquake model

  1. Improvements in Nonconservative Force Modelling for TOPEX/POSEIDON

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Rowlands, David D.; Chinn, Douglas S.; Kubitschek, Daniel G.; Luthcke, Scott B.; Zelensky, Nikita B.; Born, George H.

    1999-01-01

    It was recognized prior to the launch of TOPEX/POSEIDON, that the most important source of orbit error other than the gravity field, was due to nonconservative force modelling. Accordingly, an intensive effort was undertaken to study the nonconservative forces acting on the spacecraft using detailed finite element modelling (Antreasian, 1992; Antreasian and Rosborough, 1992). However, this detailed modelling was not suitable for orbit determination, and a simplified eight plate "box-wing" model was developed that took into account the aggregate effect of the various materials and associated thermal properties of each spacecraft surface. The a priori model was later tuned post launch with actual tracking data [Nerem et al., 1994; Marshall and Luthcke, 1994; Marshall et al., 1995]. More recently, Kubitschek (1997] developed a newer box-wing model for TOPEX/POSEIDON, which included updated material properties, accounted for a solar array deflection, and modelled solar array warping due to thermal effects. We have used this updated model as a basis to retune the macromodel for TOPEX/POSEIDON, and report on preliminary results using at least 36 cycles (one year) of SLR and DORIS data in 1993.

  2. Improvements in Nonconservative Force Modelling for TOPEX/POSEIDON

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Rowlands, David D.; Chinn, Douglas S.; Kubitschek, Daniel G.; Luthcke, Scott B.; Zelensky, Nikita B.; Born, George H.

    1999-01-01

    It was recognized prior to the launch of TOPEX/POSEIDON, that the most important source of orbit error other than the gravity field, was due to nonconservative force modelling. Accordingly, an intensive effort was undertaken to study the nonconservative forces acting on the spacecraft using detailed finite element modelling (Antreasian, 1992; Antreasian and Rosborough, 1992). However, this detailed modelling was not suitable for orbit determination, and a simplified eight plate "box-wing" model was developed that took into account the aggregate effect of the various materials and associated thermal properties of each spacecraft surface. The a priori model was later tuned post launch with actual tracking data [Nerem et al., 1994; Marshall and Luthcke, 1994; Marshall et al., 1995]. More recently, Kubitschek (1997] developed a newer box-wing model for TOPEX/POSEIDON, which included updated material properties, accounted for a solar array deflection, and modelled solar array warping due to thermal effects. We have used this updated model as a basis to retune the macromodel for TOPEX/POSEIDON, and report on preliminary results using at least 36 cycles (one year) of SLR and DORIS data in 1993.

  3. Phase diagram and density large deviations of a nonconserving ABC model.

    PubMed

    Cohen, O; Mukamel, D

    2012-02-10

    The effect of particle-nonconserving processes on the steady state of driven diffusive systems is studied within the context of a generalized ABC model. It is shown that in the limit of slow nonconserving processes, the large deviation function of the overall particle density can be computed by making use of the steady-state density profile of the conserving model. In this limit one can define a chemical potential and identify first order transitions via Maxwell's construction, similarly to what is done in equilibrium systems. This method may be applied to other driven models subjected to slow nonconserving dynamics.

  4. An uncertainty inclusive un-mixing model to identify tracer non-conservativeness

    NASA Astrophysics Data System (ADS)

    Sherriff, Sophie; Rowan, John; Franks, Stewart; Fenton, Owen; Jordan, Phil; hUallacháin, Daire Ó.

    2015-04-01

    Sediment fingerprinting is being increasingly recognised as an essential tool for catchment soil and water management. Selected physico-chemical properties (tracers) of soils and river sediments are used in a statistically-based 'un-mixing' model to apportion sediment delivered to the catchment outlet (target) to its upstream sediment sources. Development of uncertainty-inclusive approaches, taking into account uncertainties in the sampling, measurement and statistical un-mixing, are improving the robustness of results. However, methodological challenges remain including issues of particle size and organic matter selectivity and non-conservative behaviour of tracers - relating to biogeochemical transformations along the transport pathway. This study builds on our earlier uncertainty-inclusive approach (FR2000) to detect and assess the impact of tracer non-conservativeness using synthetic data before applying these lessons to new field data from Ireland. Un-mixing was conducted on 'pristine' and 'corrupted' synthetic datasets containing three to fifty tracers (in the corrupted dataset one target tracer value was manually corrupted to replicate non-conservative behaviour). Additionally, a smaller corrupted dataset was un-mixed using a permutation version of the algorithm. Field data was collected in an 11 km2 river catchment in Ireland. Source samples were collected from topsoils, subsoils, channel banks, open field drains, damaged road verges and farm tracks. Target samples were collected using time integrated suspended sediment samplers at the catchment outlet at 6-12 week intervals from July 2012 to June 2013. Samples were dried (<40°C), sieved (125 µm) and analysed for mineral magnetic susceptibility, anhysteretic remanence and iso-thermal remanence, and geochemical elements Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn (following microwave-assisted acid digestion). Discriminant analysis was used to reduce the number of tracer numbers before un-mixing. Tracer non-conservativeness

  5. Nonconservative force model parameter estimation strategy for TOPEX/Poseidon precision orbit determination

    NASA Astrophysics Data System (ADS)

    Luthcke, S. B.; Marshall, J. A.

    1992-11-01

    The TOPEX/Poseidon spacecraft was launched on August 10, 1992 to study the Earth's oceans. To achieve maximum benefit from the altimetric data it is to collect, mission requirements dictate that TOPEX/Poseidon's orbit must be computed at an unprecedented level of accuracy. To reach our pre-launch radial orbit accuracy goals, the mismodeling of the radiative nonconservative forces of solar radiation, Earth albedo an infrared re-radiation, and spacecraft thermal imbalances cannot produce in combination more than a 6 cm rms error over a 10 day period. Similarly, the 10-day drag modeling error cannot exceed 3 cm rms. In order to satisfy these requirements, a 'box-wing' representation of the satellite has been developed in which, the satellite is modelled as the combination of flat plates arranged in the shape of a box and a connected solar array. The radiative/thermal nonconservative forces acting on each of the eight surfaces are computed independently, yielding vector accelerations which are summed to compute the total aggregate effect on the satellite center-of-mass. Select parameters associated with the flat plates are adjusted to obtain a better representation of the satellite acceleration history. This study analyzes the estimation of these parameters from simulated TOPEX/Poseidon laser data in the presence of both nonconservative and gravity model errors. A 'best choice' of estimated parameters is derived and the ability to meet mission requirements with the 'box-wing' model evaluated.

  6. Nonconservative force model parameter estimation strategy for TOPEX/Poseidon precision orbit determination

    NASA Technical Reports Server (NTRS)

    Luthcke, S. B.; Marshall, J. A.

    1992-01-01

    The TOPEX/Poseidon spacecraft was launched on August 10, 1992 to study the Earth's oceans. To achieve maximum benefit from the altimetric data it is to collect, mission requirements dictate that TOPEX/Poseidon's orbit must be computed at an unprecedented level of accuracy. To reach our pre-launch radial orbit accuracy goals, the mismodeling of the radiative nonconservative forces of solar radiation, Earth albedo an infrared re-radiation, and spacecraft thermal imbalances cannot produce in combination more than a 6 cm rms error over a 10 day period. Similarly, the 10-day drag modeling error cannot exceed 3 cm rms. In order to satisfy these requirements, a 'box-wing' representation of the satellite has been developed in which, the satellite is modelled as the combination of flat plates arranged in the shape of a box and a connected solar array. The radiative/thermal nonconservative forces acting on each of the eight surfaces are computed independently, yielding vector accelerations which are summed to compute the total aggregate effect on the satellite center-of-mass. Select parameters associated with the flat plates are adjusted to obtain a better representation of the satellite acceleration history. This study analyzes the estimation of these parameters from simulated TOPEX/Poseidon laser data in the presence of both nonconservative and gravity model errors. A 'best choice' of estimated parameters is derived and the ability to meet mission requirements with the 'box-wing' model evaluated.

  7. Gravity and Nonconservative Force Model Tuning for the GEOSAT Follow-On Spacecraft

    NASA Technical Reports Server (NTRS)

    Lemoine, Frank G.; Zelensky, Nikita P.; Rowlands, David D.; Luthcke, Scott B.; Chinn, Douglas S.; Marr, Gregory C.; Smith, David E. (Technical Monitor)

    2000-01-01

    The US Navy's GEOSAT Follow-On spacecraft was launched on February 10, 1998 and the primary objective of the mission was to map the oceans using a radar altimeter. Three radar altimeter calibration campaigns have been conducted in 1999 and 2000. The spacecraft is tracked by satellite laser ranging (SLR) and Doppler beacons and a limited amount of data have been obtained from the Global Positioning Receiver (GPS) on board the satellite. Even with EGM96, the predicted radial orbit error due to gravity field mismodelling (to 70x70) remains high at 2.61 cm (compared to 0.88 cm for TOPEX). We report on the preliminary gravity model tuning for GFO using SLR, and altimeter crossover data. Preliminary solutions using SLR and GFO/GFO crossover data from CalVal campaigns I and II in June-August 1999, and January-February 2000 have reduced the predicted radial orbit error to 1.9 cm and further reduction will be possible when additional data are added to the solutions. The gravity model tuning has improved principally the low order m-daily terms and has reduced significantly the geographically correlated error present in this satellite orbit. In addition to gravity field mismodelling, the largest contributor to the orbit error is the non-conservative force mismodelling. We report on further nonconservative force model tuning results using available data from over one cycle in beta prime.

  8. Hamiltonian formulation of the spin-orbit model with time-varying non-conservative forces

    NASA Astrophysics Data System (ADS)

    Gkolias, Ioannis; Efthymiopoulos, Christos; Pucacco, Giuseppe; Celletti, Alessandra

    2017-10-01

    In a realistic scenario, the evolution of the rotational dynamics of a celestial or artificial body is subject to dissipative effects. Time-varying non-conservative forces can be due to, for example, a variation of the moments of inertia or to tidal interactions. In this work, we consider a simplified model describing the rotational dynamics, known as the spin-orbit problem, where we assume that the orbital motion is provided by a fixed Keplerian ellipse. We consider different examples in which a non-conservative force acts on the model and we propose an analytical method, which reduces the system to a Hamiltonian framework. In particular, we compute a time parametrisation in a series form, which allows us to transform the original system into a Hamiltonian one. We also provide applications of our method to study the rotational motion of a body with time-varying moments of inertia, e.g. an artificial satellite with flexible components, as well as subject to a tidal torque depending linearly on the velocity.

  9. Noether's theorem for non-conservative Hamilton system based on El-Nabulsi dynamical model extended by periodic laws

    NASA Astrophysics Data System (ADS)

    Long, Zi-Xuan; Zhang, Yi

    2014-11-01

    This paper focuses on the Noether symmetries and the conserved quantities for both holonomic and nonholonomic systems based on a new non-conservative dynamical model introduced by El-Nabulsi. First, the El-Nabulsi dynamical model which is based on a fractional integral extended by periodic laws is introduced, and El-Nabulsi—Hamilton's canonical equations for non-conservative Hamilton system with holonomic or nonholonomic constraints are established. Second, the definitions and criteria of El-Nabulsi—Noether symmetrical transformations and quasi-symmetrical transformations are presented in terms of the invariance of El-Nabulsi—Hamilton action under the infinitesimal transformations of the group. Finally, Noether's theorems for the non-conservative Hamilton system under the El-Nabulsi dynamical system are established, which reveal the relationship between the Noether symmetry and the conserved quantity of the system.

  10. Earthquake likelihood model testing

    USGS Publications Warehouse

    Schorlemmer, D.; Gerstenberger, M.C.; Wiemer, S.; Jackson, D.D.; Rhoades, D.A.

    2007-01-01

    INTRODUCTIONThe Regional Earthquake Likelihood Models (RELM) project aims to produce and evaluate alternate models of earthquake potential (probability per unit volume, magnitude, and time) for California. Based on differing assumptions, these models are produced to test the validity of their assumptions and to explore which models should be incorporated in seismic hazard and risk evaluation. Tests based on physical and geological criteria are useful but we focus on statistical methods using future earthquake catalog data only. We envision two evaluations: a test of consistency with observed data and a comparison of all pairs of models for relative consistency. Both tests are based on the likelihood method, and both are fully prospective (i.e., the models are not adjusted to fit the test data). To be tested, each model must assign a probability to any possible event within a specified region of space, time, and magnitude. For our tests the models must use a common format: earthquake rates in specified “bins” with location, magnitude, time, and focal mechanism limits.Seismology cannot yet deterministically predict individual earthquakes; however, it should seek the best possible models for forecasting earthquake occurrence. This paper describes the statistical rules of an experiment to examine and test earthquake forecasts. The primary purposes of the tests described below are to evaluate physical models for earthquakes, assure that source models used in seismic hazard and risk studies are consistent with earthquake data, and provide quantitative measures by which models can be assigned weights in a consensus model or be judged as suitable for particular regions.In this paper we develop a statistical method for testing earthquake likelihood models. A companion paper (Schorlemmer and Gerstenberger 2007, this issue) discusses the actual implementation of these tests in the framework of the RELM initiative.Statistical testing of hypotheses is a common task and a

  11. Probabilistic modeling of earthquakes

    NASA Astrophysics Data System (ADS)

    Duputel, Z.; Jolivet, R.; Jiang, J.; Simons, M.; Rivera, L. A.; Ampuero, J. P.; Gombert, B.; Minson, S. E.

    2015-12-01

    By exploiting increasing amounts of geophysical data we are able to produce increasingly sophisticated fault slip models. Such detailed models, while they are essential ingredients towards better understanding fault mechanical behavior, can only inform us in a meaningful way if we can assign uncertainties to the inferred slip parameters. This talk will present our recent efforts to infer fault slip models with realistic error estimates. Bayesian analysis is a useful tool for this purpose as it handles uncertainty in a natural way. One of the biggest obstacles to significant progress in observational earthquake source modeling arises from imperfect predictions of geodetic and seismic data due to uncertainties in the material parameters and fault geometries used in our forward models - the impact of which are generally overlooked. We recently developed physically based statistics for the model prediction error and showed how to account for inaccuracies in the Earth model elastic parameters. We will present applications of this formalism to recent large earthquakes such as the 2014 Pisagua earthquake. We will also discuss novel approaches to integrate the large amount of information available from GPS, InSAR, tide-gauge, tsunami and seismic data.

  12. Nonconservative kinetic exchange model of opinion dynamics with randomness and bounded confidence.

    PubMed

    Sen, Parongama

    2012-07-01

    The concept of a bounded confidence level is incorporated in a nonconservative kinetic exchange model of opinion dynamics model where opinions have continuous values ∈[-1,1]. The characteristics of the unrestricted model, which has one parameter λ representing conviction, undergo drastic changes with the introduction of bounded confidence parametrized by δ. Three distinct regions are identified in the phase diagram in the δ-λ plane and the evidences of a first order phase transition for δ ≥ 0.3 are presented. A neutral state with all opinions equal to zero occurs for λ ≤ λ(c1) ≃ 2/3, independent of δ, while for λ(c(1)) ≤ λ ≤ λ(c(2))(δ), an ordered region is seen to exist where opinions of only one sign prevail. At λ(c(2))(δ), a transition to a disordered state is observed, where individual opinions of both signs coexist and move closer to the extreme values (±1) as λ is increased. For confidence level δ < 0.3, the ordered phase exists for a narrow range of λ only. The line δ = 0 is apparently a line of discontinuity, and this limit is discussed in some detail.

  13. Nonextensive models for earthquakes.

    PubMed

    Silva, R; França, G S; Vilar, C S; Alcaniz, J S

    2006-02-01

    We have revisited the fragment-asperity interaction model recently introduced by Sotolongo-Costa and Posadas [Phy. Rev. Lett. 92, 048501 (2004)] by considering a different definition for mean values in the context of Tsallis nonextensive statistics and introducing a scale between the earthquake energy and the size of fragment epsilon proportional to r3. The energy-distribution function (EDF) deduced in our approach is considerably different from the one obtained in the above reference. We have also tested the viability of this EDF with data from two different catalogs (in three different areas), namely, the NEIC and the Bulletin Seismic of the Revista Brasileira de Geofísica. Although both approaches provide very similar values for the nonextensive parameter , other physical quantities, e.g., energy density, differ considerably by several orders of magnitude.

  14. Nonextensive models for earthquakes

    NASA Astrophysics Data System (ADS)

    Silva, R.; França, G. S.; Vilar, C. S.; Alcaniz, J. S.

    2006-02-01

    We have revisited the fragment-asperity interaction model recently introduced by Sotolongo-Costa and Posadas [Phy. Rev. Lett. 92, 048501 (2004)] by considering a different definition for mean values in the context of Tsallis nonextensive statistics and introducing a scale between the earthquake energy and the size of fragment γ∝r3 . The energy-distribution function (EDF) deduced in our approach is considerably different from the one obtained in the above reference. We have also tested the viability of this EDF with data from two different catalogs (in three different areas), namely, the NEIC and the Bulletin Seismic of the Revista Brasileira de Geofísica. Although both approaches provide very similar values for the nonextensive parameter q , other physical quantities, e.g., energy density, differ considerably by several orders of magnitude.

  15. Two models for earthquake forerunners

    USGS Publications Warehouse

    Mjachkin, V.I.; Brace, W.F.; Sobolev, G.A.; Dieterich, J.H.

    1975-01-01

    Similar precursory phenomena have been observed before earthquakes in the United States, the Soviet Union, Japan, and China. Two quite different physical models are used to explain these phenomena. According to a model developed by US seismologists, the so-called dilatancy diffusion model, the earthquake occurs near maximum stress, following a period of dilatant crack expansion. Diffusion of water in and out of the dilatant volume is required to explain the recovery of seismic velocity before the earthquake. According to a model developed by Soviet scientists growth of cracks is also involved but diffusion of water in and out of the focal region is not required. With this model, the earthquake is assumed to occur during a period of falling stress and recovery of velocity here is due to crack closure as stress relaxes. In general, the dilatancy diffusion model gives a peaked precursor form, whereas the dry model gives a bay form, in which recovery is well under way before the earthquake. A number of field observations should help to distinguish between the two models: study of post-earthquake recovery, time variation of stress and pore pressure in the focal region, the occurrence of pre-existing faults, and any changes in direction of precursory phenomena during the anomalous period. ?? 1975 Birkha??user Verlag.

  16. An improved GRACE monthly gravity field solution by modeling the non-conservative acceleration and attitude observation errors

    NASA Astrophysics Data System (ADS)

    Chen, Qiujie; Shen, Yunzhong; Chen, Wu; Zhang, Xingfu; Hsu, Houze

    2016-06-01

    The main contribution of this study is to improve the GRACE gravity field solution by taking errors of non-conservative acceleration and attitude observations into account. Unlike previous studies, the errors of the attitude and non-conservative acceleration data, and gravity field parameters, as well as accelerometer biases are estimated by means of weighted least squares adjustment. Then we compute a new time series of monthly gravity field models complete to degree and order 60 covering the period Jan. 2003 to Dec. 2012 from the twin GRACE satellites' data. The derived GRACE solution (called Tongji-GRACE02) is compared in terms of geoid degree variances and temporal mass changes with the other GRACE solutions, namely CSR RL05, GFZ RL05a, and JPL RL05. The results show that (1) the global mass signals of Tongji-GRACE02 are generally consistent with those of CSR RL05, GFZ RL05a, and JPL RL05; (2) compared to CSR RL05, the noise of Tongji-GRACE02 is reduced by about 21 % over ocean when only using 300 km Gaussian smoothing, and 60 % or more over deserts (Australia, Kalahari, Karakum and Thar) without using Gaussian smoothing and decorrelation filtering; and (3) for all examples, the noise reductions are more significant than signal reductions, no matter whether smoothing and filtering are applied or not. The comparison with GLDAS data supports that the signals of Tongji-GRACE02 over St. Lawrence River basin are close to those from CSR RL05, GFZ RL05a and JPL RL05, while the GLDAS result shows the best agreement with the Tongji-GRACE02 result.

  17. Bayesian kinematic earthquake source models

    NASA Astrophysics Data System (ADS)

    Minson, S. E.; Simons, M.; Beck, J. L.; Genrich, J. F.; Galetzka, J. E.; Chowdhury, F.; Owen, S. E.; Webb, F.; Comte, D.; Glass, B.; Leiva, C.; Ortega, F. H.

    2009-12-01

    Most coseismic, postseismic, and interseismic slip models are based on highly regularized optimizations which yield one solution which satisfies the data given a particular set of regularizing constraints. This regularization hampers our ability to answer basic questions such as whether seismic and aseismic slip overlap or instead rupture separate portions of the fault zone. We present a Bayesian methodology for generating kinematic earthquake source models with a focus on large subduction zone earthquakes. Unlike classical optimization approaches, Bayesian techniques sample the ensemble of all acceptable models presented as an a posteriori probability density function (PDF), and thus we can explore the entire solution space to determine, for example, which model parameters are well determined and which are not, or what is the likelihood that two slip distributions overlap in space. Bayesian sampling also has the advantage that all a priori knowledge of the source process can be used to mold the a posteriori ensemble of models. Although very powerful, Bayesian methods have up to now been of limited use in geophysical modeling because they are only computationally feasible for problems with a small number of free parameters due to what is called the "curse of dimensionality." However, our methodology can successfully sample solution spaces of many hundreds of parameters, which is sufficient to produce finite fault kinematic earthquake models. Our algorithm is a modification of the tempered Markov chain Monte Carlo (tempered MCMC or TMCMC) method. In our algorithm, we sample a "tempered" a posteriori PDF using many MCMC simulations running in parallel and evolutionary computation in which models which fit the data poorly are preferentially eliminated in favor of models which better predict the data. We present results for both synthetic test problems as well as for the 2007 Mw 7.8 Tocopilla, Chile earthquake, the latter of which is constrained by InSAR, local high

  18. Modeling, Forecasting and Mitigating Extreme Earthquakes

    NASA Astrophysics Data System (ADS)

    Ismail-Zadeh, A.; Le Mouel, J.; Soloviev, A.

    2012-12-01

    Recent earthquake disasters highlighted the importance of multi- and trans-disciplinary studies of earthquake risk. A major component of earthquake disaster risk analysis is hazards research, which should cover not only a traditional assessment of ground shaking, but also studies of geodetic, paleoseismic, geomagnetic, hydrological, deep drilling and other geophysical and geological observations together with comprehensive modeling of earthquakes and forecasting extreme events. Extreme earthquakes (large magnitude and rare events) are manifestations of complex behavior of the lithosphere structured as a hierarchical system of blocks of different sizes. Understanding of physics and dynamics of the extreme events comes from observations, measurements and modeling. A quantitative approach to simulate earthquakes in models of fault dynamics will be presented. The models reproduce basic features of the observed seismicity (e.g., the frequency-magnitude relationship, clustering of earthquakes, occurrence of extreme seismic events). They provide a link between geodynamic processes and seismicity, allow studying extreme events, influence of fault network properties on seismic patterns and seismic cycles, and assist, in a broader sense, in earthquake forecast modeling. Some aspects of predictability of large earthquakes (how well can large earthquakes be predicted today?) will be also discussed along with possibilities in mitigation of earthquake disasters (e.g., on 'inverse' forensic investigations of earthquake disasters).

  19. Network of epicenters of the Olami-Feder-Christensen model of earthquakes.

    PubMed

    Peixoto, Tiago P; Prado, Carmen P C

    2006-07-01

    We study the dynamics of the Olami-Feder-Christensen (OFC) model of earthquakes, focusing on the behavior of sequences of epicenters regarded as a growing complex network. Besides making a detailed and quantitative study of the effects of the borders (the occurrence of epicenters is dominated by a strong border effect which does not scale with system size), we examine the degree distribution and the degree correlation of the graph. We detect sharp differences between the conservative and nonconservative regimes of the model. Removing border effects, the conservative regime exhibits a Poisson-like degree statistics and is uncorrelated, while the nonconservative has a broad power-law-like distribution of degrees (if the smallest events are ignored), which reproduces the observed behavior of real earthquakes. In this regime the graph has also an unusually strong degree correlation among the vertices with higher degree, which is the result of the existence of temporary attractors for the dynamics: as the system evolves, the epicenters concentrate increasingly on fewer sites, exhibiting strong synchronization, but eventually spread again over the lattice after a series of sufficiently large earthquakes. We propose an analytical description of the dynamics of this growing network, considering a Markov process network with hidden variables, which is able to account for the mentioned properties.

  20. GEM - The Global Earthquake Model

    NASA Astrophysics Data System (ADS)

    Smolka, A.

    2009-04-01

    Over 500,000 people died in the last decade due to earthquakes and tsunamis, mostly in the developing world, where the risk is increasing due to rapid population growth. In many seismic regions, no hazard and risk models exist, and even where models do exist, they are intelligible only by experts, or available only for commercial purposes. The Global Earthquake Model (GEM) answers the need for an openly accessible risk management tool. GEM is an internationally sanctioned public private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) which will establish an authoritative standard for calculating and communicating earthquake hazard and risk, and will be designed to serve as the critical instrument to support decisions and actions that reduce earthquake losses worldwide. GEM will integrate developments on the forefront of scientific and engineering knowledge of earthquakes, at global, regional and local scale. The work is organized in three modules: hazard, risk, and socio-economic impact. The hazard module calculates probabilities of earthquake occurrence and resulting shaking at any given location. The risk module calculates fatalities, injuries, and damage based on expected shaking, building vulnerability, and the distribution of population and of exposed values and facilities. The socio-economic impact module delivers tools for making educated decisions to mitigate and manage risk. GEM will be a versatile online tool, with open source code and a map-based graphical interface. The underlying data will be open wherever possible, and its modular input and output will be adapted to multiple user groups: scientists and engineers, risk managers and decision makers in the public and private sectors, and the public-at- large. GEM will be the first global model for seismic risk assessment at a national and regional scale, and aims to achieve broad scientific participation and independence. Its development will occur in a

  1. Parity-nonconserving cold neutron-parahydrogen interactions

    NASA Astrophysics Data System (ADS)

    Partanen, T. M.

    2012-12-01

    Three pion-dominated observables of the parity-nonconserving interactions between the cold neutrons and parahydrogen are calculated. The transversely polarized neutron spin rotation, unpolarized neutron longitudinal polarization, and photon asymmetry of the radiative polarized neutron capture are considered. For the numerical evaluation of the observables, the strong interactions are taken into account by the Reid93 potential and the parity-nonconserving interactions by the DDH and EFT models including two different EFT parity-nonconserving two-pion exchange potentials.

  2. Properties of foreshocks and aftershocks of the nonconservative self-organized critical Olami-Feder-Christensen model.

    PubMed

    Helmstetter, Agnès; Hergarten, Stefan; Sornette, Didier

    2004-10-01

    Following Phys. Rev. Lett. 88, 238501 (2002)] who discovered aftershocks and foreshocks in the Olami-Feder-Christensen (OFC) discrete block-spring earthquake model, we investigate to what degree the simple toppling mechanism of this model is sufficient to account for the clustering of real seismicity in time and space. We find that synthetic catalogs generated by the OFC model share many properties of real seismicity at a qualitative level: Omori's law (aftershocks) and inverse Omori's law (foreshocks), increase of the number of aftershocks and of the aftershock zone size with the mainshock magnitude. There are, however, significant quantitative differences. The number of aftershocks per mainshock in the OFC model is smaller than in real seismicity, especially for large mainshocks. We find that foreshocks in the OFC catalogs can be in large part described by a simple model of triggered seismicity, such as the epidemic-type aftershock sequence (ETAS) model. But the properties of foreshocks in the OFC model depend on the mainshock magnitude, in qualitative agreement with the critical earthquake model and in disagreement with real seismicity and with the ETAS model.

  3. Properties of foreshocks and aftershocks of the nonconservative self-organized critical Olami-Feder-Christensen model

    SciTech Connect

    Helmstetter, Agnes; Hergarten, Stefan; Sornette, Didier

    2004-10-01

    Following Hergarten and Neugebauer [Phys. Rev. Lett. 88, 238501, 2002] who discovered aftershocks and foreshocks in the Olami-Feder-Christensen (OFC) discrete block-spring earthquake model, we investigate to what degree the simple toppling mechanism of this model is sufficient to account for the clustering of real seismicity in time and space. We find that synthetic catalogs generated by the OFC model share many properties of real seismicity at a qualitative level: Omori's law (aftershocks) and inverse Omori's law (foreshocks), increase of the number of aftershocks and of the aftershock zone size with the mainshock magnitude. There are, however, significant quantitative differences. The number of aftershocks per mainshock in the OFC model is smaller than in real seismicity, especially for large mainshocks. We find that foreshocks in the OFC catalogs can be in large part described by a simple model of triggered seismicity, such as the epidemic-type aftershock sequence (ETAS) model. But the properties of foreshocks in the OFC model depend on the mainshock magnitude, in qualitative agreement with the critical earthquake model and in disagreement with real seismicity and with the ETAS model.

  4. Statistical tests of simple earthquake cycle models

    NASA Astrophysics Data System (ADS)

    DeVries, Phoebe M. R.; Evans, Eileen L.

    2016-12-01

    A central goal of observing and modeling the earthquake cycle is to forecast when a particular fault may generate an earthquake: a fault late in its earthquake cycle may be more likely to generate an earthquake than a fault early in its earthquake cycle. Models that can explain geodetic observations throughout the entire earthquake cycle may be required to gain a more complete understanding of relevant physics and phenomenology. Previous efforts to develop unified earthquake models for strike-slip faults have largely focused on explaining both preseismic and postseismic geodetic observations available across a few faults in California, Turkey, and Tibet. An alternative approach leverages the global distribution of geodetic and geologic slip rate estimates on strike-slip faults worldwide. Here we use the Kolmogorov-Smirnov test for similarity of distributions to infer, in a statistically rigorous manner, viscoelastic earthquake cycle models that are inconsistent with 15 sets of observations across major strike-slip faults. We reject a large subset of two-layer models incorporating Burgers rheologies at a significance level of α = 0.05 (those with long-term Maxwell viscosities ηM < 4.0 × 1019 Pa s and ηM > 4.6 × 1020 Pa s) but cannot reject models on the basis of transient Kelvin viscosity ηK. Finally, we examine the implications of these results for the predicted earthquake cycle timing of the 15 faults considered and compare these predictions to the geologic and historical record.

  5. High precision analytical modelling of the solar non-conservative force field

    NASA Astrophysics Data System (ADS)

    Ziebart, M.; Adhya, S.; Cross, P.

    2003-04-01

    This paper outlines an automated analytical technique for solar radiation pressure and thermal re-radiation modelling that deals with spacecraft structural complexity, is applicable to many different types of spacecraft, and is simple to use. The technique utilises a simulation of the photon flux based on a pixel array and includes approaches for the thermal response of solar panels and multi-layered insulation. The rationale behind this approach is explained and the details of the modelling method are outlined. The roles of the technique at the stages of design, operation and post-processing analysis are defined. The effects of variations in the solar irradiance are discussed, as is the adaptation of the technique for the analysis of solar radiation torque. Importantly, practical implementation of the output model does not result in any degradation of the source data used in the analysis. The benefits of this technique over empirical approaches are discussed, using results from recent studies. The technique has been applied to the GLONASS IIn spacecraft, and is currently being applied to GPS Block IIR, JASON-1 and ENVISAT.

  6. Parallelization of the Coupled Earthquake Model

    NASA Technical Reports Server (NTRS)

    Block, Gary; Li, P. Peggy; Song, Yuhe T.

    2007-01-01

    This Web-based tsunami simulation system allows users to remotely run a model on JPL s supercomputers for a given undersea earthquake. At the time of this reporting, predicting tsunamis on the Internet has never happened before. This new code directly couples the earthquake model and the ocean model on parallel computers and improves simulation speed. Seismometers can only detect information from earthquakes; they cannot detect whether or not a tsunami may occur as a result of the earthquake. When earthquake-tsunami models are coupled with the improved computational speed of modern, high-performance computers and constrained by remotely sensed data, they are able to provide early warnings for those coastal regions at risk. The software is capable of testing NASA s satellite observations of tsunamis. It has been successfully tested for several historical tsunamis, has passed all alpha and beta testing, and is well documented for users.

  7. Multiplicative earthquake likelihood models incorporating strain rates

    NASA Astrophysics Data System (ADS)

    Rhoades, D. A.; Christophersen, A.; Gerstenberger, M. C.

    2017-01-01

    SUMMARYWe examine the potential for strain-rate variables to improve long-term <span class="hlt">earthquake</span> likelihood <span class="hlt">models</span>. We derive a set of multiplicative hybrid <span class="hlt">earthquake</span> likelihood <span class="hlt">models</span> in which cell rates in a spatially uniform baseline <span class="hlt">model</span> are scaled using combinations of covariates derived from <span class="hlt">earthquake</span> catalogue data, fault data, and strain-rates for the New Zealand region. Three components of the strain rate estimated from GPS data over the period 1991-2011 are considered: the shear, rotational and dilatational strain rates. The hybrid <span class="hlt">model</span> parameters are optimised for <span class="hlt">earthquakes</span> of M 5 and greater over the period 1987-2006 and tested on <span class="hlt">earthquakes</span> from the period 2012-2015, which is independent of the strain rate estimates. The shear strain rate is overall the most informative individual covariate, as indicated by Molchan error diagrams as well as multiplicative <span class="hlt">modelling</span>. Most <span class="hlt">models</span> including strain rates are significantly more informative than the best <span class="hlt">models</span> excluding strain rates in both the fitting and testing period. A hybrid that combines the shear and dilatational strain rates with a smoothed seismicity covariate is the most informative <span class="hlt">model</span> in the fitting period, and a simpler <span class="hlt">model</span> without the dilatational strain rate is the most informative in the testing period. These results have implications for probabilistic seismic hazard analysis and can be used to improve the background <span class="hlt">model</span> component of medium-term and short-term <span class="hlt">earthquake</span> forecasting <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70187588','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70187588"><span>Statistical tests of simple <span class="hlt">earthquake</span> cycle <span class="hlt">models</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>Devries, Phoebe M. R.; Evans, Eileen</p> <p>2016-01-01</p> <p>A central goal of observing and <span class="hlt">modeling</span> the <span class="hlt">earthquake</span> cycle is to forecast when a particular fault may generate an <span class="hlt">earthquake</span>: a fault late in its <span class="hlt">earthquake</span> cycle may be more likely to generate an <span class="hlt">earthquake</span> than a fault early in its <span class="hlt">earthquake</span> cycle. <span class="hlt">Models</span> that can explain geodetic observations throughout the entire <span class="hlt">earthquake</span> cycle may be required to gain a more complete understanding of relevant physics and phenomenology. Previous efforts to develop unified <span class="hlt">earthquake</span> <span class="hlt">models</span> for strike-slip faults have largely focused on explaining both preseismic and postseismic geodetic observations available across a few faults in California, Turkey, and Tibet. An alternative approach leverages the global distribution of geodetic and geologic slip rate estimates on strike-slip faults worldwide. Here we use the Kolmogorov-Smirnov test for similarity of distributions to infer, in a statistically rigorous manner, viscoelastic <span class="hlt">earthquake</span> cycle <span class="hlt">models</span> that are inconsistent with 15 sets of observations across major strike-slip faults. We reject a large subset of two-layer <span class="hlt">models</span> incorporating Burgers rheologies at a significance level of α = 0.05 (those with long-term Maxwell viscosities ηM <~ 4.0 × 1019 Pa s and ηM >~ 4.6 × 1020 Pa s) but cannot reject <span class="hlt">models</span> on the basis of transient Kelvin viscosity ηK. Finally, we examine the implications of these results for the predicted <span class="hlt">earthquake</span> cycle timing of the 15 faults considered and compare these predictions to the geologic and historical record.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1215479A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1215479A"><span><span class="hlt">Earthquake</span> Risk <span class="hlt">Modelling</span> - Opening the black box</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alarcon, John E.; Simic, Milan; Franco, Guillermo; Shen-Tu, Bingming</p> <p>2010-05-01</p> <p>Assessing the risk from natural catastrophes such as <span class="hlt">earthquakes</span> involves the detailed study of the seismic sources and site conditions that contribute to the <span class="hlt">earthquake</span> hazard in the region of interest, the distribution and particular characteristics of the exposures through the study of building stock and its vulnerabilities, and the application of specific financial terms for particular portfolios. The catastrophe <span class="hlt">modelling</span> framework encompasses these relatively complex considerations while also including a measure of uncertainty. This paper describes succinctly the structure and modules included in a probabilistic catastrophe risk <span class="hlt">model</span> and presents several examples of risk <span class="hlt">modelling</span> for realistic scenarios such as the expected <span class="hlt">earthquakes</span> in the Marmara Sea region of Turkey and the results from <span class="hlt">modelling</span> the 2009 L'Aquila (Abruzzo) <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/467932','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/467932"><span>New geological perspectives on <span class="hlt">earthquake</span> recurrence <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Schwartz, D.P.</p> <p>1997-02-01</p> <p>In most areas of the world the record of historical seismicity is too short or uncertain to accurately characterize the future distribution of <span class="hlt">earthquakes</span> of different sizes in time and space. Most faults have not ruptured once, let alone repeatedly. Ultimately, the ability to correctly forecast the magnitude, location, and probability of future <span class="hlt">earthquakes</span> depends on how well one can quantify the past behavior of <span class="hlt">earthquake</span> sources. Paleoseismological trenching of active faults, historical surface ruptures, liquefaction features, and shaking-induced ground deformation structures provides fundamental information on the past behavior of <span class="hlt">earthquake</span> sources. These studies quantify (a) the timing of individual past <span class="hlt">earthquakes</span> and fault slip rates, which lead to estimates of recurrence intervals and the development of recurrence <span class="hlt">models</span> and (b) the amount of displacement during individual events, which allows estimates of the sizes of past <span class="hlt">earthquakes</span> on a fault. When timing and slip per event are combined with information on fault zone geometry and structure, <span class="hlt">models</span> that define individual rupture segments can be developed. Paleoseismicity data, in the form of timing and size of past events, provide a window into the driving mechanism of the <span class="hlt">earthquake</span> engine--the cycle of stress build-up and release.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6087382','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6087382"><span><span class="hlt">Model</span> for repetitive cycles of large <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Newman, W.I.; Knopoff, L.</p> <p>1983-04-01</p> <p>The theory of the fusion of small cracks into large ones reproduces certain features also observed in the clustering of <span class="hlt">earthquake</span> sequences. By modifying our earlier <span class="hlt">model</span> to take into account the stress release associated with the occurrence of large <span class="hlt">earthquakes</span>, we obtain repetitive periodic cycles of large <span class="hlt">earthquakes</span>. A preliminary conclusion is that a combination of the stress release or elastic rebound mechanism plus time delays in the fusion process are sufficient to destabilize the crack populations and, ultimately, give rise to repetitive episodes of seismicity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22038562','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22038562"><span>Parity <span class="hlt">nonconservation</span> in ytterbium ion</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sahoo, B. K.; Das, B. P.</p> <p>2011-07-15</p> <p>We consider parity <span class="hlt">nonconservation</span> (PNC) in singly ionized ytterbium (Yb{sup +}) arising from the neutral current weak interaction. We calculate the PNC electric dipole transition amplitude (E1{sub PNC}) and the properties associated with it using relativistic coupled-cluster theory. E1{sub PNC} for the [4f{sup 14}] {sup 2}6s{yields}[4f{sup 14}] {sup 2}5d{sub 3/2} transition in Yb{sup +} has been evaluated to within an accuracy of 5%. The improvement of this result is possible. It therefore appears that this ion is a promising candidate for testing the standard <span class="hlt">model</span> of particle physics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.S23C..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.S23C..02M"><span><span class="hlt">Earthquake</span> interdependence and insurance loss <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muir Wood, R.</p> <p>2005-12-01</p> <p>Probabilistic Catastrophe loss <span class="hlt">modeling</span> generally assumes that <span class="hlt">earthquakes</span> are independent events and occur far enough apart in time that damage from one event is fully restituted before another <span class="hlt">earthquake</span> occurs. While time dependence and cascade fault rupturing are today standard elements of the <span class="hlt">earthquake</span> hazard engine, in the next generation of Catastrophe loss <span class="hlt">models</span> one can expect to find a more comprehensive range of <span class="hlt">earthquake</span> interdependence represented in a full simulation <span class="hlt">modeling</span> environment. Such behavior includes the incorporation of the ways in which <span class="hlt">earthquakes</span> relate one to another in both space and time (including foreshock, aftershock and triggered mainshock distinctions) and the damage that can be predicted from overlapping damage fields as related to the length of time for reconstruction that has elapsed between events. For insurance purposes losses are framed by the 168 hour clause for classifying losses as falling within the same `event' for reinsurance recoveries as well as the annual insurance contract. The understanding of the ways in which stress changes associated with fault rupture affect the probabilities of <span class="hlt">earthquakes</span> on surrounding faults has also expanded the predictability of potential <span class="hlt">earthquake</span> sequences as well as highlighted the potential to identify locations where, for some time window, risk can be discounted. While it can be illuminating to explore the loss and insurance implications of the patterns of historical <span class="hlt">earthquake</span> occurrence seen historically along the Nankaido subduction zone of Southern Japan, in New Madrid from 1811-1812, or Nevada in 1954, the sequences to be expected in the future are unlikely to have historical precedent in the region in which they form.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S31C4409S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S31C4409S"><span>Distributed Slip <span class="hlt">Model</span> for Simulating Virtual <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>Shani-Kadmiel, S.; Tsesarsky, M.; Gvirtzman, Z.</p> <p>2014-12-01</p> <p>We develop a physics based, generic finite fault source, which we call the Distributed Slip <span class="hlt">Model</span> (DSM) for simulating large virtual <span class="hlt">earthquakes</span>. This task is a necessary step towards ground motion prediction in <span class="hlt">earthquake</span>-prone areas with limited instrumental coverage. A reliable ground motion prediction based on virtual <span class="hlt">earthquakes</span> must account for site, path, and source effects. Assessment of site effect mainly depends on near-surface material properties which are relatively well constrained, using geotechnical site data and borehole measurements. Assessment of path effect depends on the deeper geological structure, which is also typically known to an acceptable resolution. Contrarily to these two effects, which remain constant for a given area of interest, the <span class="hlt">earthquake</span> rupture process and geometry varies from one <span class="hlt">earthquake</span> to the other. In this study we focus on a finite fault source representation which is both generic and physics-based, for simulating large <span class="hlt">earthquakes</span> where limited knowledge is available. Thirteen geometric and kinematic parameters are used to describe the smooth "pseudo-Gaussian" slip distribution, such that slip decays from a point of peak slip within an elliptical rupture patch to zero at the borders of the patch. Radiation pattern and spectral charectaristics of our DSM are compared to those of commonly used finite fault <span class="hlt">models</span>, i.e., the classical Haskell's <span class="hlt">Model</span> (HM) and the modified HM with Radial Rupture Propagation (HM-RRP) and the Point Source <span class="hlt">Model</span> (PSM). Ground motion prediction based on our DSM benefits from the symmetry of the PSM and the directivity of the HM while overcoming inadequacy for <span class="hlt">modeling</span> large <span class="hlt">earthquakes</span> of the former and the non-physical uniform slip of the latter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1616671S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1616671S"><span>The Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> - Past, Present, Future</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smolka, Anselm; Schneider, John; Stein, Ross</p> <p>2014-05-01</p> <p>The Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> (GEM) is a unique collaborative effort that aims to provide organizations and individuals with tools and resources for transparent assessment of <span class="hlt">earthquake</span> risk anywhere in the world. By pooling data, knowledge and people, GEM acts as an international forum for collaboration and exchange. Sharing of data and risk information, best practices, and approaches across the globe are key to assessing risk more effectively. Through consortium driven global projects, open-source IT development and collaborations with more than 10 regions, leading experts are developing unique global datasets, best practice, open tools and <span class="hlt">models</span> for seismic hazard and risk assessment. The year 2013 has seen the completion of ten global data sets or components addressing various aspects of <span class="hlt">earthquake</span> hazard and risk, as well as two GEM-related, but independently managed regional projects SHARE and EMME. Notably, the International Seismological Centre (ISC) led the development of a new ISC-GEM global instrumental <span class="hlt">earthquake</span> catalogue, which was made publicly available in early 2013. It has set a new standard for global <span class="hlt">earthquake</span> catalogues and has found widespread acceptance and application in the global <span class="hlt">earthquake</span> community. By the end of 2014, GEM's OpenQuake computational platform will provide the OpenQuake hazard/risk assessment software and integrate all GEM data and information products. The public release of OpenQuake is planned for the end of this 2014, and will comprise the following datasets and <span class="hlt">models</span>: • ISC-GEM Instrumental <span class="hlt">Earthquake</span> Catalogue (released January 2013) • Global <span class="hlt">Earthquake</span> History Catalogue [1000-1903] • Global Geodetic Strain Rate Database and <span class="hlt">Model</span> • Global Active Fault Database • Tectonic Regionalisation <span class="hlt">Model</span> • Global Exposure Database • Buildings and Population Database • <span class="hlt">Earthquake</span> Consequences Database • Physical Vulnerabilities Database • Socio-Economic Vulnerability and Resilience Indicators • Seismic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4459208','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4459208"><span>On the <span class="hlt">earthquake</span> predictability of fault interaction <span class="hlt">models</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>Marzocchi, W; Melini, D</p> <p>2014-01-01</p> <p>Space-time clustering is the most striking departure of large <span class="hlt">earthquakes</span> occurrence process from randomness. These clusters are usually described ex-post by a physics-based <span class="hlt">model</span> in which <span class="hlt">earthquakes</span> are triggered by Coulomb stress changes induced by other surrounding <span class="hlt">earthquakes</span>. Notwithstanding the popularity of this kind of <span class="hlt">modeling</span>, its ex-ante skill in terms of <span class="hlt">earthquake</span> predictability gain is still unknown. Here we show that even in synthetic systems that are rooted on the physics of fault interaction using the Coulomb stress changes, such a kind of <span class="hlt">modeling</span> often does not increase significantly <span class="hlt">earthquake</span> predictability. <span class="hlt">Earthquake</span> predictability of a fault may increase only when the Coulomb stress change induced by a nearby <span class="hlt">earthquake</span> is much larger than the stress changes caused by <span class="hlt">earthquakes</span> on other faults and by the intrinsic variability of the <span class="hlt">earthquake</span> occurrence process. PMID:26074643</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.8294M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.8294M"><span>On the <span class="hlt">earthquake</span> predictability of fault interaction <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marzocchi, W.; Melini, D.</p> <p>2014-12-01</p> <p>Space-time clustering is the most striking departure of large <span class="hlt">earthquakes</span> occurrence process from randomness. These clusters are usually described ex-post by a physics-based <span class="hlt">model</span> in which <span class="hlt">earthquakes</span> are triggered by Coulomb stress changes induced by other surrounding <span class="hlt">earthquakes</span>. Notwithstanding the popularity of this kind of <span class="hlt">modeling</span>, its ex-ante skill in terms of <span class="hlt">earthquake</span> predictability gain is still unknown. Here we show that even in synthetic systems that are rooted on the physics of fault interaction using the Coulomb stress changes, such a kind of <span class="hlt">modeling</span> often does not increase significantly <span class="hlt">earthquake</span> predictability. <span class="hlt">Earthquake</span> predictability of a fault may increase only when the Coulomb stress change induced by a nearby <span class="hlt">earthquake</span> is much larger than the stress changes caused by <span class="hlt">earthquakes</span> on other faults and by the intrinsic variability of the <span class="hlt">earthquake</span> occurrence process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25314453','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25314453"><span>Aftershocks in a frictional <span class="hlt">earthquake</span> <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Braun, O M; Tosatti, Erio</p> <p>2014-09-01</p> <p>Inspired by spring-block <span class="hlt">models</span>, we elaborate a "minimal" physical <span class="hlt">model</span> of <span class="hlt">earthquakes</span> which reproduces two main empirical seismological laws, the Gutenberg-Richter law and the Omori aftershock law. Our point is to demonstrate that the simultaneous incorporation of aging of contacts in the sliding interface and of elasticity of the sliding plates constitutes the minimal ingredients to account for both laws within the same frictional <span class="hlt">model</span>.</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://www.ncbi.nlm.nih.gov/pubmed/11607669','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11607669"><span>Slip complexity in <span class="hlt">earthquake</span> fault <span class="hlt">models</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rice, J R; Ben-Zion, Y</p> <p>1996-04-30</p> <p>We summarize studies of <span class="hlt">earthquake</span> fault <span class="hlt">models</span> that give rise to slip complexities like those in natural <span class="hlt">earthquakes</span>. For <span class="hlt">models</span> of smooth faults between elastically deformable continua, it is critical that the friction laws involve a characteristic distance for slip weakening or evolution of surface state. That results in a finite nucleation size, or coherent slip patch size, h*. <span class="hlt">Models</span> of smooth faults, using numerical cell size properly small compared to h*, show periodic response or complex and apparently chaotic histories of large events but have not been found to show small event complexity like the self-similar (power law) Gutenberg-Richter frequency-size statistics. This conclusion is supported in the present paper by fully inertial elastodynamic <span class="hlt">modeling</span> of <span class="hlt">earthquake</span> sequences. In contrast, some <span class="hlt">models</span> of locally heterogeneous faults with quasi-independent fault segments, represented approximately by simulations with cell size larger than h* so that the <span class="hlt">model</span> becomes "inherently discrete," do show small event complexity of the Gutenberg-Richter type. <span class="hlt">Models</span> based on classical friction laws without a weakening length scale or for which the numerical procedure imposes an abrupt strength drop at the onset of slip have h* = 0 and hence always fall into the inherently discrete class. We suggest that the small-event complexity that some such <span class="hlt">models</span> show will not survive regularization of the constitutive description, by inclusion of an appropriate length scale leading to a finite h*, and a corresponding reduction of numerical grid size.</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_1");'>1</a></li> <li class="active"><span>2</span></li> <li><a href="#" onclick='return showDiv("page_3");'>3</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><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_2 --> <div id="page_3" 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_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</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="41"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3189015','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3189015"><span>Results of the Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> (RELM) test of <span class="hlt">earthquake</span> forecasts in California</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lee, Ya-Ting; Turcotte, Donald L.; Holliday, James R.; Sachs, Michael K.; Rundle, John B.; Chen, Chien-Chih; Tiampo, Kristy F.</p> <p>2011-01-01</p> <p>The Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> (RELM) test of <span class="hlt">earthquake</span> forecasts in California was the first competitive evaluation of forecasts of future <span class="hlt">earthquake</span> occurrence. Participants submitted expected probabilities of occurrence of M≥4.95 <span class="hlt">earthquakes</span> in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M≥4.95 <span class="hlt">earthquakes</span> occurred in the test region. These <span class="hlt">earthquakes</span> occurred in 22 test cells. This seismic activity was dominated by <span class="hlt">earthquakes</span> associated with the M = 7.2, April 4, 2010, El Mayor–Cucapah <span class="hlt">earthquake</span> in northern Mexico. This <span class="hlt">earthquake</span> occurred in the test region, and 16 of the other 30 <span class="hlt">earthquakes</span> in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most “successful” in terms of the locations of future <span class="hlt">earthquakes</span>. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts. PMID:21949355</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21949355','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21949355"><span>Results of the Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> (RELM) test of <span class="hlt">earthquake</span> forecasts in California.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lee, Ya-Ting; Turcotte, Donald L; Holliday, James R; Sachs, Michael K; Rundle, John B; Chen, Chien-Chih; Tiampo, Kristy F</p> <p>2011-10-04</p> <p>The Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> (RELM) test of <span class="hlt">earthquake</span> forecasts in California was the first competitive evaluation of forecasts of future <span class="hlt">earthquake</span> occurrence. Participants submitted expected probabilities of occurrence of M ≥ 4.95 <span class="hlt">earthquakes</span> in 0.1° × 0.1° cells for the period 1 January 1, 2006, to December 31, 2010. Probabilities were submitted for 7,682 cells in California and adjacent regions. During this period, 31 M ≥ 4.95 <span class="hlt">earthquakes</span> occurred in the test region. These <span class="hlt">earthquakes</span> occurred in 22 test cells. This seismic activity was dominated by <span class="hlt">earthquakes</span> associated with the M = 7.2, April 4, 2010, El Mayor-Cucapah <span class="hlt">earthquake</span> in northern Mexico. This <span class="hlt">earthquake</span> occurred in the test region, and 16 of the other 30 <span class="hlt">earthquakes</span> in the test region could be associated with it. Nine complete forecasts were submitted by six participants. In this paper, we present the forecasts in a way that allows the reader to evaluate which forecast is the most "successful" in terms of the locations of future <span class="hlt">earthquakes</span>. We conclude that the RELM test was a success and suggest ways in which the results can be used to improve future forecasts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://db.nzsee.org.nz/2011/224.pdf','USGSPUBS'); return false;" href="http://db.nzsee.org.nz/2011/224.pdf"><span>Human casualties in <span class="hlt">earthquakes</span>: <span class="hlt">modelling</span> and mitigation</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Spence, R.J.S.; So, E.K.M.</p> <p>2011-01-01</p> <p><span class="hlt">Earthquake</span> risk <span class="hlt">modelling</span> is needed for the planning of post-event emergency operations, for the development of insurance schemes, for the planning of mitigation measures in the existing building stock, and for the development of appropriate building regulations; in all of these applications estimates of casualty numbers are essential. But there are many questions about casualty estimation which are still poorly understood. These questions relate to the causes and nature of the injuries and deaths, and the extent to which they can be quantified. This paper looks at the evidence on these questions from recent studies. It then reviews casualty estimation <span class="hlt">models</span> available, and finally compares the performance of some casualty <span class="hlt">models</span> in making rapid post-event casualty estimates in recent <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNG13A1861R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNG13A1861R"><span><span class="hlt">Modeling</span> Statistical and Dynamic Features 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>Rydelek, P. A.; Suyehiro, K.; Sacks, S. I.; Smith, D. E.; Takanami, T.; Hatano, T.</p> <p>2015-12-01</p> <p>The cellular automaton <span class="hlt">earthquake</span> <span class="hlt">model</span> by Sacks and Rydelek (1995) is extended to explain spatio-temporal change in seismicity with the regional tectonic stress buildup. Our approach is to apply a simple Coulomb failure law to our <span class="hlt">model</span> space of discrete cells, which successfully reproduces empirical laws (e.g. Gutenberg-Richter law) and dynamic failure characteristics (e.g. stress drop vs. magnitude and asperities) of <span class="hlt">earthquakes</span>. Once the stress condition supersedes the Coulomb threshold on a discrete cell, its accumulated stress is transferred to only neighboring cells, which cascades to more neighboring cells to create various size ruptures. A fundamental point here is the cellular view of the continuous earth. We suggest the cell size varies regionally with the maturity of the faults of the region. Seismic gaps (e.g. Mogi, 1979) and changes in seismicity such as indicated by b-values have been known but poorly understood. There have been reports of magnitude dependent seismic quiescence before large event at plate boundaries and intraplate (Smith et al., 2013). Recently, decreases in b-value for large <span class="hlt">earthquakes</span> have been reported (Nanjo et al., 2012) as anticipated from lab experiments (Mogi, 1963). Our <span class="hlt">model</span> reproduces the b-value decrease towards eventual large <span class="hlt">earthquake</span> (increasing tectonic stress and its heterogeneous distribution). We succeeded in reproducing the cut-off of larger events above some threshold magnitude (M3-4) by slightly increasing the Coulomb failure level for only 2 % or more of the highly stressed cells. This is equivalent to reducing the pore pressure in these distributed cells. We are working on the <span class="hlt">model</span> to introduce the recovery of pore pressure incorporating the observed orders of magnitude higher permeability fault zones than the surrounding rock (Lockner, 2009) allowing for a large <span class="hlt">earthquake</span> to be generated. Our interpretation requires interactions of pores and fluids. We suggest heterogeneously distributed patches hardened</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ194839.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ194839.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>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('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://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('http://files.eric.ed.gov/fulltext/ED128723.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED128723.pdf"><span>Adult <span class="hlt">Nonconservation</span> of Numerical Equivalence.</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>Murray, Frank B.; Armstrong, Sharon L.</p> <p></p> <p>A conservation problem of numerical equivalence which 80% of adults reliably fail and 40% of third graders pass was developed, and responses of 188 subjects (Grades 2, 3, 5, 7, 9, 11 and college) to it and related number conservation and probability problems indicated that the differences in <span class="hlt">nonconservation</span> were rooted in subjects' different…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70014648','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70014648"><span>ON NONSTATIONARY STOCHASTIC <span class="hlt">MODELS</span> 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>Safak, Erdal; Boore, David M.</p> <p>1986-01-01</p> <p>A seismological stochastic <span class="hlt">model</span> for <span class="hlt">earthquake</span> ground-motion description is presented. Seismological <span class="hlt">models</span> are based on the physical properties of the source and the medium and have significant advantages over the widely used empirical <span class="hlt">models</span>. The <span class="hlt">model</span> discussed here provides a convenient form for estimating structural response by using random vibration theory. A commonly used random process for ground acceleration, filtered white-noise multiplied by an envelope function, introduces some errors in response calculations for structures whose periods are longer than the faulting duration. An alternate random process, filtered shot-noise process, eliminates these errors.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4275565','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4275565"><span><span class="hlt">Modeling</span> fast and slow <span class="hlt">earthquakes</span> at various scales</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>IDE, Satoshi</p> <p>2014-01-01</p> <p><span class="hlt">Earthquake</span> sources represent dynamic rupture within rocky materials at depth and often can be <span class="hlt">modeled</span> as propagating shear slip controlled by friction laws. These laws provide boundary conditions on fault planes embedded in elastic media. Recent developments in observation networks, laboratory experiments, and methods of data analysis have expanded our knowledge of the physics of <span class="hlt">earthquakes</span>. Newly discovered slow <span class="hlt">earthquakes</span> are qualitatively different phenomena from ordinary fast <span class="hlt">earthquakes</span> and provide independent information on slow deformation at depth. Many numerical simulations have been carried out to <span class="hlt">model</span> both fast and slow <span class="hlt">earthquakes</span>, but problems remain, especially with scaling laws. Some mechanisms are required to explain the power-law nature of <span class="hlt">earthquake</span> rupture and the lack of characteristic length. Conceptual <span class="hlt">models</span> that include a hierarchical structure over a wide range of scales would be helpful for characterizing diverse behavior in different seismic regions and for improving probabilistic forecasts of <span class="hlt">earthquakes</span>. PMID:25311138</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25311138','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25311138"><span><span class="hlt">Modeling</span> fast and slow <span class="hlt">earthquakes</span> at various scales.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ide, Satoshi</p> <p>2014-01-01</p> <p><span class="hlt">Earthquake</span> sources represent dynamic rupture within rocky materials at depth and often can be <span class="hlt">modeled</span> as propagating shear slip controlled by friction laws. These laws provide boundary conditions on fault planes embedded in elastic media. Recent developments in observation networks, laboratory experiments, and methods of data analysis have expanded our knowledge of the physics of <span class="hlt">earthquakes</span>. Newly discovered slow <span class="hlt">earthquakes</span> are qualitatively different phenomena from ordinary fast <span class="hlt">earthquakes</span> and provide independent information on slow deformation at depth. Many numerical simulations have been carried out to <span class="hlt">model</span> both fast and slow <span class="hlt">earthquakes</span>, but problems remain, especially with scaling laws. Some mechanisms are required to explain the power-law nature of <span class="hlt">earthquake</span> rupture and the lack of characteristic length. Conceptual <span class="hlt">models</span> that include a hierarchical structure over a wide range of scales would be helpful for characterizing diverse behavior in different seismic regions and for improving probabilistic forecasts of <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39441','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39441"><span>Slip complexity in <span class="hlt">earthquake</span> fault <span class="hlt">models</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>Rice, J R; Ben-Zion, Y</p> <p>1996-01-01</p> <p>We summarize studies of <span class="hlt">earthquake</span> fault <span class="hlt">models</span> that give rise to slip complexities like those in natural <span class="hlt">earthquakes</span>. For <span class="hlt">models</span> of smooth faults between elastically deformable continua, it is critical that the friction laws involve a characteristic distance for slip weakening or evolution of surface state. That results in a finite nucleation size, or coherent slip patch size, h*. <span class="hlt">Models</span> of smooth faults, using numerical cell size properly small compared to h*, show periodic response or complex and apparently chaotic histories of large events but have not been found to show small event complexity like the self-similar (power law) Gutenberg-Richter frequency-size statistics. This conclusion is supported in the present paper by fully inertial elastodynamic <span class="hlt">modeling</span> of <span class="hlt">earthquake</span> sequences. In contrast, some <span class="hlt">models</span> of locally heterogeneous faults with quasi-independent fault segments, represented approximately by simulations with cell size larger than h* so that the <span class="hlt">model</span> becomes "inherently discrete," do show small event complexity of the Gutenberg-Richter type. <span class="hlt">Models</span> based on classical friction laws without a weakening length scale or for which the numerical procedure imposes an abrupt strength drop at the onset of slip have h* = 0 and hence always fall into the inherently discrete class. We suggest that the small-event complexity that some such <span class="hlt">models</span> show will not survive regularization of the constitutive description, by inclusion of an appropriate length scale leading to a finite h*, and a corresponding reduction of numerical grid size. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:11607669</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006Tectp.417..141C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006Tectp.417..141C"><span>Physical and stochastic <span class="hlt">models</span> of <span class="hlt">earthquake</span> clustering</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; Murru, Maura; Catalli, Flaminia</p> <p>2006-04-01</p> <p>The phenomenon of <span class="hlt">earthquake</span> clustering, i.e., the increase of occurrence probability for seismic events close in space and time to other previous <span class="hlt">earthquakes</span>, has been <span class="hlt">modeled</span> both by statistical and physical processes. From a statistical viewpoint the so-called epidemic <span class="hlt">model</span> (ETAS) introduced by Ogata in 1988 and its variations have become fairly well known in the seismological community. Tests on real seismicity and comparison with a plain time-independent Poissonian <span class="hlt">model</span> through likelihood-based methods have reliably proved their validity. On the other hand, in the last decade many papers have been published on the so-called Coulomb stress change principle, based on the theory of elasticity, showing qualitatively that an increase of the Coulomb stress in a given area is usually associated with an increase of seismic activity. More specifically, the rate-and-state theory developed by Dieterich in the '90s has been able to give a physical justification to the phenomenon known as Omori law. According to this law, a mainshock is followed by a series of aftershocks whose frequency decreases in time as an inverse power law. In this study we give an outline of the above-mentioned stochastic and physical <span class="hlt">models</span>, and build up an approach by which these <span class="hlt">models</span> can be merged in a single algorithm and statistically tested. The application to the seismicity of Japan from 1970 to 2003 shows that the new <span class="hlt">model</span> incorporating the physical concept of the rate-and-state theory performs not worse than the purely stochastic <span class="hlt">model</span> with two free parameters only. The numerical results obtained in these applications are related to physical characters of the <span class="hlt">model</span> as the stress change produced by an <span class="hlt">earthquake</span> close to its edges and to the A and σ parameters of the rate-and-state constitutive law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70023307','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70023307"><span>The failure of <span class="hlt">earthquake</span> failure <span class="hlt">models</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.</p> <p>2001-01-01</p> <p>In this study I show that simple heuristic <span class="hlt">models</span> and numerical calculations suggest that an entire class of commonly invoked <span class="hlt">models</span> of <span class="hlt">earthquake</span> failure processes cannot explain triggering of seismicity by transient or "dynamic" stress changes, such as stress changes associated with passing seismic waves. The <span class="hlt">models</span> of this class have the common feature that the physical property characterizing failure increases at an accelerating rate when a fault is loaded (stressed) at a constant rate. Examples include <span class="hlt">models</span> that invoke rate state friction or subcritical crack growth, in which the properties characterizing failure are slip or crack length, respectively. Failure occurs when the rate at which these grow accelerates to values exceeding some critical threshold. These accelerating failure <span class="hlt">models</span> do not predict the finite durations of dynamically triggered <span class="hlt">earthquake</span> sequences (e.g., at aftershock or remote distances). Some of the failure <span class="hlt">models</span> belonging to this class have been used to explain static stress triggering of aftershocks. This may imply that the physical processes underlying dynamic triggering differs or that currently applied <span class="hlt">models</span> of static triggering require modification. If the former is the case, we might appeal to physical mechanisms relying on oscillatory deformations such as compaction of saturated fault gouge leading to pore pressure increase, or cyclic fatigue. However, if dynamic and static triggering mechanisms differ, one still needs to ask why static triggering <span class="hlt">models</span> that neglect these dynamic mechanisms appear to explain many observations. If the static and dynamic triggering mechanisms are the same, perhaps assumptions about accelerating failure and/or that triggering advances the failure times of a population of inevitable <span class="hlt">earthquakes</span> are incorrect.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.4484T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.4484T"><span>Calibration and validation of <span class="hlt">earthquake</span> catastrophe <span class="hlt">models</span>. Case study: Impact Forecasting <span class="hlt">Earthquake</span> <span class="hlt">Model</span> for Algeria</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Trendafiloski, G.; Gaspa Rebull, O.; Ewing, C.; Podlaha, A.; Magee, B.</p> <p>2012-04-01</p> <p>Calibration and validation are crucial steps in the production of the catastrophe <span class="hlt">models</span> for the insurance industry in order to assure the <span class="hlt">model</span>'s reliability and to quantify its uncertainty. Calibration is needed in all components of <span class="hlt">model</span> development including hazard and vulnerability. Validation is required to ensure that the losses calculated by the <span class="hlt">model</span> match those observed in past events and which could happen in future. Impact Forecasting, the catastrophe <span class="hlt">modelling</span> development centre of excellence within Aon Benfield, has recently launched its <span class="hlt">earthquake</span> <span class="hlt">model</span> for Algeria as a part of the <span class="hlt">earthquake</span> <span class="hlt">model</span> for the Maghreb region. The <span class="hlt">earthquake</span> <span class="hlt">model</span> went through a detailed calibration process including: (1) the seismic intensity attenuation <span class="hlt">model</span> by use of macroseismic observations and maps from past <span class="hlt">earthquakes</span> in Algeria; (2) calculation of the country-specific vulnerability modifiers by use of past damage observations in the country. The use of Benouar, 1994 ground motion prediction relationship was proven as the most appropriate for our <span class="hlt">model</span>. Calculation of the regional vulnerability modifiers for the country led to 10% to 40% larger vulnerability indexes for different building types compared to average European indexes. The country specific damage <span class="hlt">models</span> also included aggregate damage <span class="hlt">models</span> for residential, commercial and industrial properties considering the description of the buildings stock given by World Housing Encyclopaedia and the local rebuilding cost factors equal to 10% for damage grade 1, 20% for damage grade 2, 35% for damage grade 3, 75% for damage grade 4 and 100% for damage grade 5. The damage grades comply with the European Macroseismic Scale (EMS-1998). The <span class="hlt">model</span> was validated by use of "as-if" historical scenario simulations of three past <span class="hlt">earthquake</span> events in Algeria M6.8 2003 Boumerdes, M7.3 1980 El-Asnam and M7.3 1856 Djidjelli <span class="hlt">earthquake</span>. The calculated return periods of the losses for client market portfolio align with the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.S13A0204R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.S13A0204R"><span>Towards <span class="hlt">Modelling</span> slow <span class="hlt">Earthquakes</span> with Geodynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Regenauer-Lieb, K.; Yuen, D. A.</p> <p>2006-12-01</p> <p>We explore a new, properly scaled, thermal-mechanical geodynamic <span class="hlt">model</span>{^1} that can generate timescales now very close to those of <span class="hlt">earthquakes</span> and of the same order as slow <span class="hlt">earthquakes</span>. In our simulations we encounter two basically different bifurcation phenomena. One in which the shear zone nucleates in the ductile field, and the second which is fully associated with elasto-plastic (brittle, pressure- dependent) displacements. A quartz/feldspar composite slab has all two modes operating simultaneously in three different depth levels. The bottom of the crust is predominantly controlled by the elasto-visco-plastic mode while the top is controlled by the elasto-plastic mode. The exchange of the two modes appears to communicate on a sub-horizontal layer in a flip-flop fashion, which may yield a fractal-like signature in time and collapses into a critical temperature which for crustal rocks is around 500-580 K; in the middle of the brittle-ductile transition-zone. Near the critical temperature, stresses close to the ideal strength can be reached at local, meter-scale. Investigations of the thermal-mechanical properties under such extreme conditions are pivotal for understanding the physics of <span class="hlt">earthquakes</span>. 1. Regenauer-Lieb, K., Weinberg, R. & Rosenbaum, G. The effect of energy feedbacks on continental strength. Nature 442, 67-70 (2006).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20778774','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20778774"><span>Quasiperiodic Events in an <span class="hlt">Earthquake</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ramos, O.; Maaloey, K.J.; Altshuler, E.</p> <p>2006-03-10</p> <p>We introduce a modification of the Olami-Feder-Christensen <span class="hlt">earthquake</span> <span class="hlt">model</span> [Phys. Rev. Lett. 68, 1244 (1992)] in order to improve the resemblence with the Burridge-Knopoff mechanical <span class="hlt">model</span> and with possible laboratory experiments. A constant and finite force continually drives the system, resulting in instantaneous relaxations. Dynamical disorder is added to the thresholds following a narrow distribution. We find quasiperiodic behavior in the avalanche time series with a period proportional to the degree of dissipation of the system. Periodicity is not as robust as criticality when the threshold force distribution widens, or when an increasing noise is introduced in the values of the dissipation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ091669.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ091669.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>Roper, Paul J.; Roper, Jere Gerard</p> <p>1974-01-01</p> <p>Describes the causes and effects of <span class="hlt">earthquakes</span>, defines the meaning of magnitude (measured on the Richter Magnitude Scale) and intensity (measured on a modified Mercalli Intensity Scale) and discusses <span class="hlt">earthquake</span> prediction and control. (JR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=%22Earthquake+prediction%22&id=EJ091669','ERIC'); return false;" href="https://eric.ed.gov/?q=%22Earthquake+prediction%22&id=EJ091669"><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>Roper, Paul J.; Roper, Jere Gerard</p> <p>1974-01-01</p> <p>Describes the causes and effects of <span class="hlt">earthquakes</span>, defines the meaning of magnitude (measured on the Richter Magnitude Scale) and intensity (measured on a modified Mercalli Intensity Scale) and discusses <span class="hlt">earthquake</span> prediction and control. (JR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvE..92f2927S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvE..92f2927S"><span>Conservative perturbation theory for <span class="hlt">nonconservative</span> systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shah, Tirth; Chattopadhyay, Rohitashwa; Vaidya, Kedar; Chakraborty, Sagar</p> <p>2015-12-01</p> <p>In this paper, we show how to use canonical perturbation theory for dissipative dynamical systems capable of showing limit-cycle oscillations. Thus, our work surmounts the hitherto perceived barrier for canonical perturbation theory that it can be applied only to a class of conservative systems, viz., Hamiltonian systems. In the process, we also find Hamiltonian structure for an important subset of Liénard system—a paradigmatic system for <span class="hlt">modeling</span> isolated and asymptotic oscillatory state. We discuss the possibility of extending our method to encompass an even wider range of <span class="hlt">nonconservative</span> systems.</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_1");'>1</a></li> <li><a href="#" onclick='return showDiv("page_2");'>2</a></li> <li class="active"><span>3</span></li> <li><a href="#" onclick='return showDiv("page_4");'>4</a></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_3 --> <div id="page_4" 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_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</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="61"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRB..117.2307R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRB..117.2307R"><span>Fixed recurrence and slip <span class="hlt">models</span> better predict <span class="hlt">earthquake</span> behavior than the time- and slip-predictable <span class="hlt">models</span>: 2. Laboratory <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>Rubinstein, Justin L.; Ellsworth, William L.; Beeler, Nicholas M.; Kilgore, Brian D.; Lockner, David A.; Savage, Heather M.</p> <p>2012-02-01</p> <p>The behavior of individual stick-slip events observed in three different laboratory experimental configurations is better explained by a "memoryless" <span class="hlt">earthquake</span> <span class="hlt">model</span> with fixed inter-event time or fixed slip than it is by the time- and slip-predictable <span class="hlt">models</span> for <span class="hlt">earthquake</span> occurrence. We make similar findings in the companion manuscript for the behavior of natural repeating <span class="hlt">earthquakes</span>. Taken together, these results allow us to conclude that the predictions of a characteristic <span class="hlt">earthquake</span> <span class="hlt">model</span> that assumes either fixed slip or fixed recurrence interval should be preferred to the predictions of the time- and slip-predictable <span class="hlt">models</span> for all <span class="hlt">earthquakes</span>. Given that the fixed slip and recurrence <span class="hlt">models</span> are the preferred <span class="hlt">models</span> for all of the experiments we examine, we infer that in an event-to-event sense the elastic rebound <span class="hlt">model</span> underlying the time- and slip-predictable <span class="hlt">models</span> does not explain <span class="hlt">earthquake</span> behavior. This does not indicate that the elastic rebound <span class="hlt">model</span> should be rejected in a long-term-sense, but it should be rejected for short-term predictions. The time- and slip-predictable <span class="hlt">models</span> likely offer worse predictions of <span class="hlt">earthquake</span> behavior because they rely on assumptions that are too simple to explain the behavior of <span class="hlt">earthquakes</span>. Specifically, the time-predictable <span class="hlt">model</span> assumes a constant failure threshold and the slip-predictable <span class="hlt">model</span> assumes that there is a constant minimum stress. There is experimental and field evidence that these assumptions are not valid for all <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23679733','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23679733"><span>Classical mechanics of <span class="hlt">nonconservative</span> systems.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Galley, Chad R</p> <p>2013-04-26</p> <p>Hamilton's principle of stationary action lies at the foundation of theoretical physics and is applied in many other disciplines from pure mathematics to economics. Despite its utility, Hamilton's principle has a subtle pitfall that often goes unnoticed in physics: it is formulated as a boundary value problem in time but is used to derive equations of motion that are solved with initial data. This subtlety can have undesirable effects. I present a formulation of Hamilton's principle that is compatible with initial value problems. Remarkably, this leads to a natural formulation for the Lagrangian and Hamiltonian dynamics of generic <span class="hlt">nonconservative</span> systems, thereby filling a long-standing gap in classical mechanics. Thus, dissipative effects, for example, can be studied with new tools that may have applications in a variety of disciplines. The new formalism is demonstrated by two examples of <span class="hlt">nonconservative</span> systems: an object moving in a fluid with viscous drag forces and a harmonic oscillator coupled to a dissipative environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70189609','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70189609"><span>Laboratory constraints on <span class="hlt">models</span> of <span class="hlt">earthquake</span> recurrence</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.; Tullis, Terry; Junger, Jenni; Kilgore, Brian D.; Goldsby, David L.</p> <p>2014-01-01</p> <p>In this study, rock friction ‘stick-slip’ experiments are used to develop constraints on <span class="hlt">models</span> of <span class="hlt">earthquake</span> 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 <span class="hlt">earthquakes</span> driven by afterslip, or low-frequency <span class="hlt">earthquakes</span> 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 <span class="hlt">model</span>. 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 <span class="hlt">models</span>. 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRB..119.8770B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRB..119.8770B"><span>Laboratory constraints on <span class="hlt">models</span> of <span class="hlt">earthquake</span> recurrence</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.; Tullis, Terry; Junger, Jenni; Kilgore, Brian; Goldsby, David</p> <p>2014-12-01</p> <p>In this study, rock friction "stick-slip" experiments are used to develop constraints on <span class="hlt">models</span> of <span class="hlt">earthquake</span> 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 <span class="hlt">earthquakes</span> driven by afterslip, or low-frequency <span class="hlt">earthquakes</span> 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 <span class="hlt">model</span>. 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 <span class="hlt">models</span>. 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhDT.........5X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhDT.........5X"><span>Computer simulations of statistical <span class="hlt">models</span> 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>Xia, Junchao</p> <p></p> <p>The frequency-size distribution of <span class="hlt">earthquake</span> fault systems in nature has been observed to exhibit Gutenberg-Richter (power-law) scaling. Computer simulations of <span class="hlt">earthquake</span> fault <span class="hlt">models</span> have been performed to understand the mechanisms for this and other observed behavior. Understanding driven dissipative systems is also important in physics and related areas. A simple <span class="hlt">model</span> that contains the essential physics of <span class="hlt">earthquake</span> faults is the Burridge-Knopoff spring-block <span class="hlt">model</span>, which incorporates inertia and a velocity-weakening friction force. To save computer time, the Burridge-Knopoff <span class="hlt">model</span> has been simplified by neglecting inertia and assuming a moving block is overdamped. These cellular automata <span class="hlt">models</span> show scaling behavior, but only for long-range stress transfer. I generalized the original nearest-neighbor Burridge-Knopoff <span class="hlt">model</span> to incorporate a variable interaction range and did simulations to see whether the long-range Burridge-Knopoff <span class="hlt">model</span> exhibits behavior similar to the long-range cellular automata <span class="hlt">models</span>. I found that the Burridge-Knopoff <span class="hlt">model</span> exhibits richer behavior than the cellular automata <span class="hlt">models</span>, depending on the range R of the stress transfer and the friction parameter alpha, which controls how quickly the friction force deceases with increasing velocity. My main result is that there exists two scaling regimes with qualitatively different behavior. One regime is for alpha ≲ 1 and R ≫ 1 and is associated with an equilibrium spinodal critical point, consistent with the long-range cellular automata <span class="hlt">models</span>. The other regime corresponds to alpha ≳ 1 and R = 1 and might be associated with another critical point. This latter interpretation has been given by previous workers, but the nature of the critical point needs more study. I also simulated the long-range Olami-Feder-Christensen cellular automata <span class="hlt">model</span>. In the mean-field limit, the scaling of the distribution of the number of block in an event can be understood by spinodal nucleation theory</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhyA..465...62L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhyA..465...62L"><span>A new physical <span class="hlt">model</span> for <span class="hlt">earthquake</span> time interval distribution</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Guoliang</p> <p>2017-01-01</p> <p>This paper reports a new physical <span class="hlt">model</span> for time interval distribution of <span class="hlt">earthquakes</span>, which was obtained by borrowing the idea from the research in the time interval distribution of sand-dust storms. Of the <span class="hlt">model</span>, it was hypothesized that the <span class="hlt">earthquakes</span> were induced by the magma movement inside the earth, and if the speed of magma ≥ threshold value Ut, the <span class="hlt">earthquakes</span> with magnitude ≥ M occurred. With this <span class="hlt">model</span>, it was obtained that for the <span class="hlt">earthquakes</span> with magnitude ≥ M there existed lg N(> t) = c - dt, where N was the number of time intervals longer than t; the value d decreased with M. This result was also verified by analyzing the <span class="hlt">earthquake</span> data from the China <span class="hlt">Earthquake</span> Networks Center (CENC).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70044014','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70044014"><span><span class="hlt">Earthquake</span> casualty <span class="hlt">models</span> 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 <span class="hlt">models</span>. This article describes the development of the <span class="hlt">models</span> and demonstrates the loss estimation capability for <span class="hlt">earthquakes</span> that have occurred since 2007. The empirical <span class="hlt">model</span> relies on country-specific <span class="hlt">earthquake</span> loss data from past <span class="hlt">earthquakes</span> and makes use of calibrated casualty rates for future prediction. The semi-empirical and analytical <span class="hlt">models</span> 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 rates given structural collapse.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19750009700','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19750009700"><span>Water resources planning for rivers draining into Mobile Bay. Part 2: <span class="hlt">Non-conservative</span> species transport <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>April, G. C.; Liu, H. A.</p> <p>1975-01-01</p> <p>Total coliform group bacteria were selected to expand the mathematical <span class="hlt">modeling</span> capabilities of the hydrodynamic and salinity <span class="hlt">models</span> to understand their relationship to commercial fishing ventures within bay waters and to gain a clear insight into the effect that rivers draining into the bay have on water quality conditions. Parametric observations revealed that temperature factors and river flow rate have a pronounced effect on the concentration profiles, while wind conditions showed only slight effects. An examination of coliform group loading concentrations at constant river flow rates and temperature shows these loading changes have an appreciable influence on total coliform distribution within Mobile Bay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ArRMA.221.1285E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ArRMA.221.1285E"><span>Global Well-Posedness and Decay Rates of Strong Solutions to a <span class="hlt">Non-Conservative</span> Compressible Two-Fluid <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Evje, Steinar; Wang, Wenjun; Wen, Huanyao</p> <p>2016-09-01</p> <p>In this paper, we consider a compressible two-fluid <span class="hlt">model</span> with constant viscosity coefficients and unequal pressure functions {P^+neq P^-}. As mentioned in the seminal work by Bresch, Desjardins, et al. (Arch Rational Mech Anal 196:599-629, 2010) for the compressible two-fluid <span class="hlt">model</span>, where {P^+=P^-} (common pressure) is used and capillarity effects are accounted for in terms of a third-order derivative of density, the case of constant viscosity coefficients cannot be handled in their settings. Besides, their analysis relies on a special choice for the density-dependent viscosity [refer also to another reference (Commun Math Phys 309:737-755, 2012) by Bresch, Huang and Li for a study of the same <span class="hlt">model</span> in one dimension but without capillarity effects]. In this work, we obtain the global solution and its optimal decay rate (in time) with constant viscosity coefficients and some smallness assumptions. In particular, capillary pressure is taken into account in the sense that {Δ P=P^+ - P^-=fneq 0} where the difference function {f} is assumed to be a strictly decreasing function near the equilibrium relative to the fluid corresponding to {P^-}. This assumption plays an key role in the analysis and appears to have an essential stabilization effect on the <span class="hlt">model</span> in question.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EJPh...37e5202A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EJPh...37e5202A"><span>Radiation reaction as a <span class="hlt">non-conservative</span> force</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aashish, Sandeep; Haque, Asrarul</p> <p>2016-09-01</p> <p>We study a system of a finite size charged particle interacting with a radiation field by exploiting Hamilton’s principle for a <span class="hlt">non-conservative</span> system recently introduced by Galley [1]. This formulation leads to the equation of motion of the charged particle that turns out to be the same as that obtained by Jackson [2]. We show that the radiation reaction stems from the <span class="hlt">non-conservative</span> part of the effective action for a charged particle. We notice that a charge interacting with a radiation field <span class="hlt">modeled</span> as a heat bath affords a way to justify that the radiation reaction is a <span class="hlt">non-conservative</span> force. The topic is suitable for graduate courses on advanced electrodynamics and classical theory of fields.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18958916','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18958916"><span><span class="hlt">Modelling</span> the elements of country vulnerability to <span class="hlt">earthquake</span> disasters.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Asef, M R</p> <p>2008-09-01</p> <p><span class="hlt">Earthquakes</span> have probably been the most deadly form of natural disaster in the past century. Diversity of <span class="hlt">earthquake</span> specifications in terms of magnitude, intensity and frequency at the semicontinental scale has initiated various kinds of disasters at a regional scale. Additionally, diverse characteristics of countries in terms of population size, disaster preparedness, economic strength and building construction development often causes an <span class="hlt">earthquake</span> of a certain characteristic to have different impacts on the affected region. This research focuses on the appropriate criteria for identifying the severity of major <span class="hlt">earthquake</span> disasters based on some key observed symptoms. Accordingly, the article presents a methodology for identification and relative quantification of severity of <span class="hlt">earthquake</span> disasters. This has led to an <span class="hlt">earthquake</span> disaster vulnerability <span class="hlt">model</span> at the country scale. Data analysis based on this <span class="hlt">model</span> suggested a quantitative, comparative and meaningful interpretation of the vulnerability of concerned countries, and successfully explained which countries are more vulnerable to major disasters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900030879&hterms=1989+earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D1989%2Bearthquake','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900030879&hterms=1989+earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3D1989%2Bearthquake"><span>Mechanical <span class="hlt">model</span> of an <span class="hlt">earthquake</span> fault</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carlson, J. M.; Langer, J. S.</p> <p>1989-01-01</p> <p>The dynamic behavior of a simple mechanical <span class="hlt">model</span> of an <span class="hlt">earthquake</span> fault is studied. This <span class="hlt">model</span>, introduced originally by Burridge and Knopoff (1967), consists of an elastically coupled chain of masses in contact with a moving rough surface. The present version of the <span class="hlt">model</span> retains the full Newtonian dynamics with inertial effects and contains no externally imposed stochasticity or spatial inhomogeneity. The only nonlinear feature is a velocity-weakening stick-slip friction force between the masses and the moving surface. This system is being driven persistently toward a slipping instability and therefore exhibits noisy sequences of earthquakelike events. These events are observed in numerical simulations, and many of their features can be predicted analytically.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6731644','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6731644"><span>Nuclear-structure effects on parity <span class="hlt">nonconservation</span> in light nuclei</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Brown, B.A.; Richter, W.A.; Godwin, N.S.</p> <p>1980-11-24</p> <p>The nucleon-nucleon parity-<span class="hlt">nonconserving</span> potentials given by Desplangues, Donoghue, and Holstein (DDH) are used to calculate matrix elements between states of opposite parity in /sup 10/B, /sup 16/O, /sup 18/F, /sup 19/F, /sup 20/Ne, and /sup 21/Ne. The sensitivity of the parity-<span class="hlt">nonconserving</span> matrix elements to various approximations in the microscopic shell-<span class="hlt">model</span> wave functions is investigated. The final results using the DDH estimates for the weak meson-nucleon coupling constants based on the Weinberg-Salam theory are several times larger than experiment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1980PhRvL..45.1681B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1980PhRvL..45.1681B"><span>Nuclear-Structure Effects on Parity <span class="hlt">Nonconservation</span> in Light Nuclei</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brown, B. A.; Richter, W. A.; Godwin, N. S.</p> <p>1980-11-01</p> <p>The nucleon-nucleon parity-<span class="hlt">nonconserving</span> potentials given by Desplangues, Donoghue, and Holstein (DDH) are used to calculate matrix elements between states of opposite parity in 10B, 16O, 18F, 19F, 20Ne, and 21Ne. The sensitivity of the parity-<span class="hlt">nonconserving</span> matrix elements to various approximations in the microscopic shell-<span class="hlt">model</span> wave functions is investigated. The final results using the DDH estimates for the weak mesonnucleon coupling constants based on the Weinberg-Salam theory are several times larger than experiment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EPJA...48..119P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EPJA...48..119P"><span>Parity <span class="hlt">nonconserving</span> proton-proton elastic scattering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Partanen, T. M.; Niskanen, J. A.; Iqbal, M. J.</p> <p>2012-09-01</p> <p>The parity <span class="hlt">nonconserving</span> longitudinal analyzing power bar A_L is calculated in elastic ěc pp scattering at the energies below the approximate inelastic region T lab = 350 MeV. The short-ranged heavy meson ρ and ω exchanges as well as the longer-ranged 2 π exchanges (with and without intermediate NΔ configurations) are considered as the mediators of the parity <span class="hlt">nonconserving</span> interactions. The DDH "best" coupling values are used as the parity <span class="hlt">nonconserving</span> meson- NN couplings. Also three different parity <span class="hlt">nonconserving</span> two-pion exchange potentials by various authors are compared.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812568H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812568H"><span>Physically-based <span class="hlt">modelling</span> of the competition between surface uplift and erosion caused by <span class="hlt">earthquakes</span> and <span class="hlt">earthquake</span> sequences.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hovius, Niels; Marc, Odin; Meunier, Patrick</p> <p>2016-04-01</p> <p>Large <span class="hlt">earthquakes</span> deform Earth's surface and drive topographic growth in the frontal zones of mountain belts. They also induce widespread mass wasting, reducing relief. Preliminary studies have proposed that above a critical magnitude <span class="hlt">earthquake</span> would induce more erosion than uplift. Other parameters such as fault geometry or <span class="hlt">earthquake</span> depth were not considered yet. A new seismologically consistent <span class="hlt">model</span> of <span class="hlt">earthquake</span> induced landsliding allow us to explore the importance of parameters such as <span class="hlt">earthquake</span> depth and landscape steepness. We have compared these eroded volume prediction with co-seismic surface uplift computed with Okada's deformation theory. We found that the <span class="hlt">earthquake</span> depth and landscape steepness to be the most important parameters compared to the fault geometry (dip and rake). In contrast with previous studies we found that largest <span class="hlt">earthquakes</span> will always be constructive and that only intermediate size <span class="hlt">earthquake</span> (Mw ~7) may be destructive. Moreover, with landscapes insufficiently steep or <span class="hlt">earthquake</span> sources sufficiently deep <span class="hlt">earthquakes</span> are predicted to be always constructive, whatever their magnitude. We have explored the long term topographic contribution of <span class="hlt">earthquake</span> sequences, with a Gutenberg Richter distribution or with a repeating, characteristic <span class="hlt">earthquake</span> magnitude. In these <span class="hlt">models</span>, the seismogenic layer thickness, that sets the depth range over which the series of <span class="hlt">earthquakes</span> will distribute, replaces the individual <span class="hlt">earthquake</span> source depth.We found that in the case of Gutenberg-Richter behavior, relevant for the Himalayan collision for example, the mass balance could remain negative up to Mw~8 for <span class="hlt">earthquakes</span> with a sub-optimal uplift contribution (e.g., transpressive or gently-dipping <span class="hlt">earthquakes</span>). Our results indicate that <span class="hlt">earthquakes</span> have probably a more ambivalent role in topographic building than previously anticipated, and suggest that some fault systems may not induce average topographic growth over their locked zone during a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70024443','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70024443"><span>A Brownian <span class="hlt">model</span> for recurrent <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>Matthews, M.V.; Ellsworth, W.L.; Reasenberg, P.A.</p> <p>2002-01-01</p> <p>We construct a probability <span class="hlt">model</span> for rupture times on a recurrent <span class="hlt">earthquake</span> 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 <span class="hlt">earthquake</span> 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 <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">earthquakes</span> 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</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S23E..07T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S23E..07T"><span>Ensemble <span class="hlt">Model</span> <span class="hlt">Earthquake</span> Forecasts During the 2010-12 Canterbury, New Zealand, <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>Taroni, M.; Werner, M. J.; Marzocchi, W.; Zechar, J. D.</p> <p>2016-12-01</p> <p>Ensemble <span class="hlt">models</span> provide at least two advantages for <span class="hlt">earthquake</span> forecasting. Firstly, they circumvent the question of which <span class="hlt">model</span> to choose for operational purposes by objectively and transparently merging all available ones. And secondly, the optimally merged <span class="hlt">model</span> may provide better forecasts than any single <span class="hlt">model</span>. In addition, complementary or inconsistent <span class="hlt">models</span>, hypotheses and input data sets can easily be combined according to defined rules. Our purpose here is to investigate ensemble <span class="hlt">modeling</span> techniques in the context of the 2010-12 Canterbury, New Zealand, <span class="hlt">earthquake</span> sequence, for which over a dozen time-dependent <span class="hlt">earthquake</span> forecast <span class="hlt">models</span> have been developed that are currently under evaluation by the Collaboratory for the Study of <span class="hlt">Earthquake</span> Predictability (CSEP). The <span class="hlt">models</span> include recently refined and developed physics-based Coulomb stress <span class="hlt">models</span> as well as new statistical <span class="hlt">models</span> and hybrid <span class="hlt">models</span> that employ physics-based components within a statistical framework. Here, we explore ensemble <span class="hlt">modeling</span> techniques to create optimal forecasts by merging all available <span class="hlt">model</span> forecasts. The mixing of the <span class="hlt">models</span> is determined by a dynamic, weighted average over all forecasts, where the weights are determined according to a continually updated measure of past predictive skill. The ensemble <span class="hlt">model</span> thus changes from day to day, giving greater weight to more informative <span class="hlt">models</span>. We compare several methods for assembling ensemble <span class="hlt">models</span> in terms of their predictive skills during the sequence and compare the optimal <span class="hlt">models</span> with the individual best <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70034496','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70034496"><span>First Results of the Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> 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 <span class="hlt">Models</span> (RELM) working group was to formalize <span class="hlt">earthquake</span> occurrence hypotheses in the form of prospective <span class="hlt">earthquake</span> rate 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> rate forecasts, is now approximately halfway to its completion. In this paper, we describe the <span class="hlt">models</span> 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 <span class="hlt">models</span> are consistent with the observation and one <span class="hlt">model</span> 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/2017SolE....8..597R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017SolE....8..597R"><span>Analogue <span class="hlt">earthquakes</span> and seismic cycles: experimental <span class="hlt">modelling</span> across timescales</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rosenau, Matthias; Corbi, Fabio; Dominguez, Stephane</p> <p>2017-05-01</p> <p>Earth deformation is a multi-scale process ranging from seconds (seismic deformation) to millions of years (tectonic deformation). Bridging short- and long-term deformation and developing seismotectonic <span class="hlt">models</span> has been a challenge in experimental tectonics for more than a century. Since the formulation of Reid's elastic rebound theory 100 years ago, laboratory mechanical <span class="hlt">models</span> combining frictional and elastic elements have been used to study the dynamics of <span class="hlt">earthquakes</span>. In the last decade, with the advent of high-resolution monitoring techniques and new rock analogue materials, laboratory <span class="hlt">earthquake</span> experiments have evolved from simple spring-slider <span class="hlt">models</span> to scaled analogue <span class="hlt">models</span>. This evolution was accomplished by advances in seismology and geodesy along with relatively frequent occurrences of large <span class="hlt">earthquakes</span> in the past decade. This coincidence has significantly increased the quality and quantity of relevant observations in nature and triggered a new understanding of <span class="hlt">earthquake</span> dynamics. We review here the developments in analogue <span class="hlt">earthquake</span> <span class="hlt">modelling</span> with a focus on those seismotectonic scale <span class="hlt">models</span> that are directly comparable to observational data on short to long timescales. We lay out the basics of analogue <span class="hlt">modelling</span>, namely scaling, materials and monitoring, as applied in seismotectonic <span class="hlt">modelling</span>. An overview of applications highlights the contributions of analogue <span class="hlt">earthquake</span> <span class="hlt">models</span> in bridging timescales of observations including <span class="hlt">earthquake</span> statistics, rupture dynamics, ground motion, and seismic-cycle deformation up to seismotectonic evolution.</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_2");'>2</a></li> <li><a href="#" onclick='return showDiv("page_3");'>3</a></li> <li class="active"><span>4</span></li> <li><a href="#" onclick='return showDiv("page_5");'>5</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_4 --> <div id="page_5" 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_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> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="81"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.9424A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.9424A"><span>"ABC's <span class="hlt">Earthquake</span>" (Experiments and <span class="hlt">models</span> in seismology)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Almeida, Ana</p> <p>2017-04-01</p> <p>Ana Almeida, Portugal Almeida, Ana Escola Básica e Secundária Dr. Vieira de Carvalho Moreira da Maia, Portugal The purpose of this presentation, in poster format, is to disclose an activity which was planned and made by me, in a school on the north of Portugal, using a kit of materials simple and easy to use - the sismo-box. The activity "ABC's <span class="hlt">Earthquake</span>" was developed under the discipline of Natural Sciences, with students from 7th grade, geosciences teachers and other areas. The possibility of work with the sismo-box was seen as an exciting and promising opportunity to promote science, seismology more specifically, to do science, when using the existing <span class="hlt">models</span> in the box and with them implement the scientific method, to work and consolidate content and skills in the area of Natural Sciences, to have a time of sharing these materials with classmates, and also with other teachers from the different areas. Throughout the development of the activity, either with students or teachers, it was possible to see the admiration by the <span class="hlt">models</span> presented in the <span class="hlt">earthquake</span>-box, as well as, the interest and the enthusiasm in wanting to move and understand what the results after the proposed procedure in the script. With this activity, we managed to promote: - educational success in this subject; a "school culture" with active participation, with quality, rules, discipline and citizenship values; fully integration of students with special educational needs; strengthen the performance of the school as a cultural, informational and formation institution; provide activities to date and innovative; foment knowledge "to be, being and doing" and contribute to a moment of joy and discovery.Learn by doing!</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39440','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39440"><span>Rock friction and its implications for <span class="hlt">earthquake</span> prediction examined via <span class="hlt">models</span> of Parkfield <span class="hlt">earthquakes</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>Tullis, T E</p> <p>1996-01-01</p> <p>The friction of rocks in the laboratory is a function of time, velocity of sliding, and displacement. Although the processes responsible for these dependencies are unknown, constitutive equations have been developed that do a reasonable job of describing the laboratory behavior. These constitutive laws have been used to create a <span class="hlt">model</span> of <span class="hlt">earthquakes</span> at Parkfield, CA, by using boundary conditions appropriate for the section of the fault that slips in magnitude 6 <span class="hlt">earthquakes</span> every 20-30 years. The behavior of this <span class="hlt">model</span> prior to the <span class="hlt">earthquakes</span> is investigated to determine whether or not the <span class="hlt">model</span> <span class="hlt">earthquakes</span> could be predicted in the real world by using realistic instruments and instrument locations. Premonitory slip does occur in the <span class="hlt">model</span>, but it is relatively restricted in time and space and detecting it from the surface may be difficult. The magnitude of the strain rate at the earth's surface due to this accelerating slip seems lower than the detectability limit of instruments in the presence of earth noise. Although not specifically <span class="hlt">modeled</span>, microseismicity related to the accelerating creep and to creep events in the <span class="hlt">model</span> should be detectable. In fact the logarithm of the moment rate on the hypocentral cell of the fault due to slip increases linearly with minus the logarithm of the time to the <span class="hlt">earthquake</span>. This could conceivably be used to determine when the <span class="hlt">earthquake</span> was going to occur. An unresolved question is whether this pattern of accelerating slip could be recognized from the microseismicity, given the discrete nature of seismic events. Nevertheless, the <span class="hlt">model</span> results suggest that the most likely solution to <span class="hlt">earthquake</span> prediction is to look for a pattern of acceleration in microseismicity and thereby identify the microearthquakes as foreshocks. Images Fig. 4 Fig. 4 Fig. 5 Fig. 7 PMID:11607668</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11607668','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11607668"><span>Rock friction and its implications for <span class="hlt">earthquake</span> prediction examined via <span class="hlt">models</span> of Parkfield <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>Tullis, T E</p> <p>1996-04-30</p> <p>The friction of rocks in the laboratory is a function of time, velocity of sliding, and displacement. Although the processes responsible for these dependencies are unknown, constitutive equations have been developed that do a reasonable job of describing the laboratory behavior. These constitutive laws have been used to create a <span class="hlt">model</span> of <span class="hlt">earthquakes</span> at Parkfield, CA, by using boundary conditions appropriate for the section of the fault that slips in magnitude 6 <span class="hlt">earthquakes</span> every 20-30 years. The behavior of this <span class="hlt">model</span> prior to the <span class="hlt">earthquakes</span> is investigated to determine whether or not the <span class="hlt">model</span> <span class="hlt">earthquakes</span> could be predicted in the real world by using realistic instruments and instrument locations. Premonitory slip does occur in the <span class="hlt">model</span>, but it is relatively restricted in time and space and detecting it from the surface may be difficult. The magnitude of the strain rate at the earth's surface due to this accelerating slip seems lower than the detectability limit of instruments in the presence of earth noise. Although not specifically <span class="hlt">modeled</span>, microseismicity related to the accelerating creep and to creep events in the <span class="hlt">model</span> should be detectable. In fact the logarithm of the moment rate on the hypocentral cell of the fault due to slip increases linearly with minus the logarithm of the time to the <span class="hlt">earthquake</span>. This could conceivably be used to determine when the <span class="hlt">earthquake</span> was going to occur. An unresolved question is whether this pattern of accelerating slip could be recognized from the microseismicity, given the discrete nature of seismic events. Nevertheless, the <span class="hlt">model</span> results suggest that the most likely solution to <span class="hlt">earthquake</span> prediction is to look for a pattern of acceleration in microseismicity and thereby identify the microearthquakes as foreshocks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5616334','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5616334"><span><span class="hlt">Modeling</span> <span class="hlt">earthquake</span> ground motion with an <span class="hlt">earthquake</span> simulation program (EMPSYN) that utilizes empirical Green's functions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hutchings, L.</p> <p>1992-01-01</p> <p>This report outlines a method of using empirical Green's functions in an <span class="hlt">earthquake</span> simulation program EMPSYN that provides realistic seismograms from potential <span class="hlt">earthquakes</span>. The theory for using empirical Green's functions is developed, implementation of the theory in EMPSYN is outlined, and an example is presented where EMPSYN is used to synthesize observed records from the 1971 San Fernando <span class="hlt">earthquake</span>. To provide useful synthetic ground motion data from potential <span class="hlt">earthquakes</span>, synthetic seismograms should <span class="hlt">model</span> frequencies from 0.5 to 15.0 Hz, the full wave-train energy distribution, and absolute amplitudes. However, high-frequency arrivals are stochastically dependent upon the inhomogeneous geologic structure and irregular fault rupture. The fault rupture can be <span class="hlt">modeled</span>, but the stochastic nature of faulting is largely an unknown factor in the <span class="hlt">earthquake</span> process. The effect of inhomogeneous geology can readily be incorporated into synthetic seismograms by using small <span class="hlt">earthquakes</span> to obtain empirical Green's functions. Small <span class="hlt">earthquakes</span> with source corner frequencies higher than the site recording limit f{sub max}, or much higher than the frequency of interest, effectively have impulsive point-fault dislocation sources, and their recordings are used as empirical Green's functions. Since empirical Green's functions are actual recordings at a site, they include the effects on seismic waves from all geologic inhomogeneities and include all recordable frequencies, absolute amplitudes, and all phases. They scale only in amplitude with differences in seismic moment. They can provide nearly the exact integrand to the representation relation. Furthermore, since their source events have spatial extent, they can be summed to simulate fault rupture without loss of information, thereby potentially computing the exact representation relation for an extended source <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=asbestos&pg=2&id=EJ621443','ERIC'); return false;" href="http://eric.ed.gov/?q=asbestos&pg=2&id=EJ621443"><span><span class="hlt">Earthquake</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>Hernandez, Hildo</p> <p>2000-01-01</p> <p>Examines the types of damage experienced by California State University at Northridge during the 1994 <span class="hlt">earthquake</span> and what lessons were learned in handling this emergency are discussed. The problem of loose asbestos is addressed. (GR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=asbestos&pg=3&id=EJ621443','ERIC'); return false;" href="https://eric.ed.gov/?q=asbestos&pg=3&id=EJ621443"><span><span class="hlt">Earthquake</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>Hernandez, Hildo</p> <p>2000-01-01</p> <p>Examines the types of damage experienced by California State University at Northridge during the 1994 <span class="hlt">earthquake</span> and what lessons were learned in handling this emergency are discussed. The problem of loose asbestos is addressed. (GR)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70013487','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70013487"><span>FORECAST <span class="hlt">MODEL</span> FOR MODERATE <span class="hlt">EARTHQUAKES</span> 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>Stuart, William D.; Archuleta, Ralph J.; Lindh, Allan G.</p> <p>1985-01-01</p> <p>The paper outlines a procedure for using an <span class="hlt">earthquake</span> instability <span class="hlt">model</span> and repeated geodetic measurements to attempt an <span class="hlt">earthquake</span> forecast. The procedure differs from other prediction methods, such as recognizing trends in data or assuming failure at a critical stress level, by using a self-contained instability <span class="hlt">model</span> that simulates both preseismic and coseismic faulting in a natural way. In short, physical theory supplies a family of curves, and the field data select the member curves whose continuation into the future constitutes a prediction. <span class="hlt">Model</span> inaccuracy and resolving power of the data determine the uncertainty of the selected curves and hence the uncertainty of the <span class="hlt">earthquake</span> time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRB..117.2306R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRB..117.2306R"><span>Fixed recurrence and slip <span class="hlt">models</span> better predict <span class="hlt">earthquake</span> behavior than the time- and slip-predictable <span class="hlt">models</span>: 1. 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>Rubinstein, Justin L.; Ellsworth, William L.; Chen, Kate H.; Uchida, Naoki</p> <p>2012-02-01</p> <p>The behavior of individual events in repeating <span class="hlt">earthquake</span> sequences in California, Taiwan and Japan is better predicted by a <span class="hlt">model</span> with fixed inter-event time or fixed slip than it is by the time- and slip-predictable <span class="hlt">models</span> for <span class="hlt">earthquake</span> occurrence. Given that repeating <span class="hlt">earthquakes</span> are highly regular in both inter-event time and seismic moment, the time- and slip-predictable <span class="hlt">models</span> 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 <span class="hlt">models</span> should be rejected in favor of <span class="hlt">earthquake</span> <span class="hlt">models</span> that assume either fixed slip or fixed recurrence interval. This implies that the elastic rebound <span class="hlt">model</span> underlying the time- and slip-predictable <span class="hlt">models</span> offers no additional value in describing <span class="hlt">earthquake</span> behavior in an event-to-event sense, but its value in a long-term sense cannot be determined. These <span class="hlt">models</span> likely fail because they rely on assumptions that oversimplify the <span class="hlt">earthquake</span> cycle. We note that the time and slip of these events is predicted quite well by fixed slip and fixed recurrence <span class="hlt">models</span>, so in some sense they are time- and slip-predictable. While fixed recurrence and slip <span class="hlt">models</span> better predict repeating <span class="hlt">earthquake</span> behavior than the time- and slip-predictable <span class="hlt">models</span>, we observe a correlation between slip and the preceding recurrence time for many repeating <span class="hlt">earthquake</span> 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 <span class="hlt">earthquake</span> sequences that do not exhibit this behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70042544','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70042544"><span>Fixed recurrence and slip <span class="hlt">models</span> better predict <span class="hlt">earthquake</span> behavior than the time- and slip-predictable <span class="hlt">models</span> 1: repeating <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>Rubinstein, Justin L.; Ellsworth, William L.; Chen, Kate Huihsuan; Uchida, Naoki</p> <p>2012-01-01</p> <p>The behavior of individual events in repeating <span class="hlt">earthquake</span> sequences in California, Taiwan and Japan is better predicted by a <span class="hlt">model</span> with fixed inter-event time or fixed slip than it is by the time- and slip-predictable <span class="hlt">models</span> for <span class="hlt">earthquake</span> occurrence. Given that repeating <span class="hlt">earthquakes</span> are highly regular in both inter-event time and seismic moment, the time- and slip-predictable <span class="hlt">models</span> 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 <span class="hlt">models</span> should be rejected in favor of <span class="hlt">earthquake</span> <span class="hlt">models</span> that assume either fixed slip or fixed recurrence interval. This implies that the elastic rebound <span class="hlt">model</span> underlying the time- and slip-predictable <span class="hlt">models</span> offers no additional value in describing <span class="hlt">earthquake</span> behavior in an event-to-event sense, but its value in a long-term sense cannot be determined. These <span class="hlt">models</span> likely fail because they rely on assumptions that oversimplify the <span class="hlt">earthquake</span> cycle. We note that the time and slip of these events is predicted quite well by fixed slip and fixed recurrence <span class="hlt">models</span>, so in some sense they are time- and slip-predictable. While fixed recurrence and slip <span class="hlt">models</span> better predict repeating <span class="hlt">earthquake</span> behavior than the time- and slip-predictable <span class="hlt">models</span>, we observe a correlation between slip and the preceding recurrence time for many repeating <span class="hlt">earthquake</span> 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 <span class="hlt">earthquake</span> sequences that do not exhibit this behavior.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/gip/7000006/report.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/gip/7000006/report.pdf"><span><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>Shedlock, Kaye M.; Pakiser, Louis Charles</p> <p>1998-01-01</p> <p>One of the most frightening and destructive phenomena of nature is a severe <span class="hlt">earthquake</span> and its terrible aftereffects. An <span class="hlt">earthquake</span> is a sudden movement of the Earth, caused by the abrupt release of strain that has accumulated over a long time. For hundreds of millions of years, the forces of plate tectonics have shaped the Earth as the huge plates that form the Earth's surface slowly move over, under, and past each other. Sometimes the movement is gradual. At other times, the plates are locked together, unable to release the accumulating energy. When the accumulated energy grows strong enough, the plates break free. If the <span class="hlt">earthquake</span> occurs in a populated area, it may cause many deaths and injuries and extensive property damage. Today we are challenging the assumption that <span class="hlt">earthquakes</span> must present an uncontrollable and unpredictable hazard to life and property. Scientists have begun to estimate the locations and likelihoods of future damaging <span class="hlt">earthquakes</span>. Sites of greatest hazard are being identified, and definite progress is being made in designing structures that will withstand the effects of <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011EPJA...47...53P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011EPJA...47...53P"><span>Parity <span class="hlt">nonconservation</span> in deuteron photoreactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Partanen, T. M.; Niskanen, J. A.</p> <p>2011-04-01</p> <p>We calculate the asymmetries in parity-<span class="hlt">nonconserving</span> deuteron photodisintegration due to circularly polarized photons ěc γ d to np with the photon laboratory energy ranging from the threshold up to 10MeV and the radiative capture of thermal polarized neutrons by protons ěc np to γ d . We use the leading-order electromagnetic Hamiltonian neglecting the smaller nuclear exchange currents. Comparative calculations are done by using the Reid93 and Argonne v18 potentials for the strong interaction and the DDH and FCDH "best" values for the weak couplings in a weak one-meson exchange potential. A weak NΔ transition potential is used to incorporate also the Δ(1232) -isobar excitation in the coupled-channels formalism.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70011768','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70011768"><span>Multiple asperity <span class="hlt">model</span> 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>Wyss, M.; Johnston, A.C.; Klein, F.W.</p> <p>1981-01-01</p> <p>Large <span class="hlt">earthquakes</span> often occur as multiple ruptures reflecting strong variations of stress level along faults. Dense instrument networks with which the volcano Kilauea is monitored provided detailed data on changes of seismic velocity, strain accumulation and <span class="hlt">earthquake</span> occurrence rate before the 1975 Hawaii 7.2-mag <span class="hlt">earthquake</span>. During the ???4 yr of preparation time the mainshock source volume had separated into crustal volumes of high stress levels embedded in a larger low-stress volume, showing respectively high- and low-stress precursory anomalies. ?? 1981 Nature Publishing Group.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19518576','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19518576"><span>Strain waves, <span class="hlt">earthquakes</span>, slow <span class="hlt">earthquakes</span>, and afterslip in the framework of the Frenkel-Kontorova <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gershenzon, N I; Bykov, V G; Bambakidis, G</p> <p>2009-05-01</p> <p>The one-dimensional Frenkel-Kontorova (FK) <span class="hlt">model</span>, well known from the theory of dislocations in crystal materials, is applied to the simulation of the process of nonelastic stress propagation along transform faults. Dynamic parameters of plate boundary <span class="hlt">earthquakes</span> as well as slow <span class="hlt">earthquakes</span> and afterslip are quantitatively described, including propagation velocity along the strike, plate boundary velocity during and after the strike, stress drop, displacement, extent of the rupture zone, and spatiotemporal distribution of stress and strain. The three fundamental speeds of plate movement, <span class="hlt">earthquake</span> migration, and seismic waves are shown to be connected in framework of the continuum FK <span class="hlt">model</span>. The magnitude of the strain wave velocity is a strong (almost exponential) function of accumulated stress or strain. It changes from a few km/s during <span class="hlt">earthquakes</span> to a few dozen km per day, month, or year during afterslip and interearthquake periods. Results of the <span class="hlt">earthquake</span> parameter calculation based on real data are in reasonable agreement with measured values. The distributions of aftershocks in this <span class="hlt">model</span> are consistent with the Omori law for temporal distribution and a 1/r for the spatial distributions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19830003371','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19830003371"><span><span class="hlt">Earthquake</span> research: Premonitory <span class="hlt">models</span> and the physics of crustal distortion</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Whitcomb, J. H.</p> <p>1981-01-01</p> <p>Seismic, gravity, and electrical resistivity data, believed to be most relevent to development of <span class="hlt">earthquake</span> premonitory <span class="hlt">models</span> of the crust, are presented. Magnetotellurics (MT) are discussed. Radon investigations are reviewed.</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> <span class="hlt">modelling</span> 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> <span class="hlt">model</span> that combines self-exciting and mutually exciting elements was developed by Ogata and Utsu from the Hawkes process. The core idea of this combined <span class="hlt">model</span> 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 rate λ(t), which is composed of the background rate, the self-exciting term (the information from past seismic events), and the external excitation term (the information from past non-seismic observations). This <span class="hlt">model</span> 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 <span class="hlt">model</span> which combines catalog-based and non-catalog-based approaches.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70035100','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70035100"><span>Toward a comprehensive areal <span class="hlt">model</span> of <span class="hlt">earthquake</span>-induced landslides</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Miles, S.B.; Keefer, D.K.</p> <p>2009-01-01</p> <p>This paper provides a review of regional-scale <span class="hlt">modeling</span> of <span class="hlt">earthquake</span>-induced landslide hazard with respect to the needs for disaster risk reduction and sustainable development. Based on this review, it sets out important research themes and suggests computing with words (CW), a methodology that includes fuzzy logic systems, as a fruitful <span class="hlt">modeling</span> methodology for addressing many of these research themes. A range of research, reviewed here, has been conducted applying CW to various aspects of <span class="hlt">earthquake</span>-induced landslide hazard zonation, but none facilitate comprehensive <span class="hlt">modeling</span> of all types of <span class="hlt">earthquake</span>-induced landslides. A new comprehensive areal <span class="hlt">model</span> of <span class="hlt">earthquake</span>-induced landslides (CAMEL) is introduced here that was developed using fuzzy logic systems. CAMEL provides an integrated framework for <span class="hlt">modeling</span> all types of <span class="hlt">earthquake</span>-induced landslides using geographic information systems. CAMEL is designed to facilitate quantitative and qualitative representation of terrain conditions and knowledge about these conditions on the likely areal concentration of each landslide type. CAMEL is highly modifiable and adaptable; new knowledge can be easily added, while existing knowledge can be changed to better match local knowledge and conditions. As such, CAMEL should not be viewed as a complete alternative to other <span class="hlt">earthquake</span>-induced landslide <span class="hlt">models</span>. CAMEL provides an open framework for incorporating other <span class="hlt">models</span>, such as Newmark's displacement method, together with previously incompatible empirical and local knowledge. ?? 2009 ASCE.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70046871','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70046871"><span><span class="hlt">Earthquake</span> recurrence <span class="hlt">models</span> fail when <span class="hlt">earthquakes</span> fail to reset the stress field</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Tormann, Thessa; Wiemer, Stefan; Hardebeck, Jeanne L.</p> <p>2012-01-01</p> <p>Parkfield's regularly occurring M6 mainshocks, about every 25 years, have over two decades stoked seismologists' hopes to successfully predict an <span class="hlt">earthquake</span> 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 <span class="hlt">models</span>, questioning once more the predictability of <span class="hlt">earthquakes</span> 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 <span class="hlt">earthquakes</span> 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 <span class="hlt">earthquakes</span> do not fully unload the stress on the fault, explaining why time recurrent <span class="hlt">models</span> fail. We present the 1989 M6.9 Loma Prieta <span class="hlt">earthquake</span> as counter example, which did release a significant portion of the stress along its fault segment and yields a substantial change in b-values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ApPhB.123..120A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ApPhB.123..120A"><span>Parity-<span class="hlt">nonconserving</span> interaction-induced light shifts in the {7S}_{1/2}-{6D}_{3/2} transition of the ultracold {^{210}{Fr}} atoms to probe new physics beyond the standard <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aoki, T.; Torii, Y.; Sahoo, B. K.; Das, B. P.; Harada, K.; Hayamizu, T.; Sakamoto, K.; Kawamura, H.; Inoue, T.; Uchiyama, A.; Ito, S.; Yoshioka, R.; Tanaka, K. S.; Itoh, M.; Hatakeyama, A.; Sakemi, Y.</p> <p>2017-04-01</p> <p>We present an experimental technique to measure light shifts due to the nuclear spin independent (NSI) parity-<span class="hlt">nonconserving</span> (PNC) interaction in the 7S_{1/2}-6D_{3/2} transition in ultracold {^{210}Fr} atoms. The approach we propose is similar to the one by Fortson (Phys Rev Lett 70:2383, 10) to measure the PNC-induced light shift which arises from the interference of parity <span class="hlt">nonconserving</span> electric dipole transition and electric quadrupole transition amplitudes. Its major advantage is that it can treat more than 10^4 ultracold {^{210}Fr} atoms to enhance the shot noise limit. A relativistic coupled-cluster method has been employed to calculate the electric dipole transition amplitudes arising from the PNC interaction. Based on these calculations, we have evaluated the PNC-induced light shifts for transitions between the hyperfine levels of the 7S_{1/2} and 6D_{3/2} states and suitable transitions are identified for carrying out PNC measurements. It is possible in principle to probe new physics beyond the standard <span class="hlt">model</span> with our proposed experimental scheme.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21028301','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21028301"><span>Discontinuous Galerkin finite element methods for hyperbolic <span class="hlt">nonconservative</span> partial differential equations</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rhebergen, S. Bokhove, O. Vegt, J.J.W. van der</p> <p>2008-01-10</p> <p>We present space- and space-time discontinuous Galerkin finite element (DGFEM) formulations for systems containing <span class="hlt">nonconservative</span> products, such as occur in dispersed multiphase flow equations. The main criterium we pose on the weak formulation is that if the system of <span class="hlt">nonconservative</span> partial differential equations can be transformed into conservative form, then the formulation must reduce to that for conservative systems. Standard DGFEM formulations cannot be applied to <span class="hlt">nonconservative</span> systems of partial differential equations. We therefore introduce the theory of weak solutions for <span class="hlt">nonconservative</span> products into the DGFEM formulation leading to the new question how to define the path connecting left and right states across a discontinuity. The effect of different paths on the numerical solution is investigated and found to be small. We also introduce a new numerical flux that is able to deal with <span class="hlt">nonconservative</span> products. Our scheme is applied to two different systems of partial differential equations. First, we consider the shallow water equations, where topography leads to <span class="hlt">nonconservative</span> products, in which the known, possibly discontinuous, topography is formally taken as an unknown in the system. Second, we consider a simplification of a depth-averaged two-phase flow <span class="hlt">model</span> which contains more intrinsic <span class="hlt">nonconservative</span> products.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/natural-disasters/earthquakes','PESTICIDES'); return false;" href="https://www.epa.gov/natural-disasters/earthquakes"><span><span class="hlt">Earthquakes</span></span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Information on this page will help you understand environmental dangers related to <span class="hlt">earthquakes</span>, what you can do to prepare and recover. It will also help you recognize possible environmental hazards and learn what you can do to protect you and your family</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('http://adsabs.harvard.edu/abs/2017EGUGA..1917121S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1917121S"><span>Prospective Evaluation of the Global <span class="hlt">Earthquake</span> Activity Rate <span class="hlt">Model</span> (GEAR1) <span class="hlt">Earthquake</span> Forecast: Preliminary Results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Strader, Anne; Schorlemmer, Danijel; Beutin, Thomas</p> <p>2017-04-01</p> <p>The Global <span class="hlt">Earthquake</span> Activity Rate <span class="hlt">Model</span> (GEAR1) is a hybrid seismicity <span class="hlt">model</span>, constructed from a loglinear combination of smoothed seismicity from the Global Centroid Moment Tensor (CMT) <span class="hlt">earthquake</span> 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 <span class="hlt">Earthquake</span> 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 <span class="hlt">models</span> were evaluated on the consistency in number (N-test), spatial (S-test) and magnitude (M-test) distribution of forecasted and observed <span class="hlt">earthquakes</span>, as well as overall data consistency (CL-, L-tests). Performance at target <span class="hlt">earthquake</span> locations was compared between <span class="hlt">models</span> using the classical paired T-test and its non-parametric equivalent, the W-test, to determine if one <span class="hlt">model</span> 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 <span class="hlt">model</span> performance, to identify regions where the GEAR1 <span class="hlt">model</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/1999/0522/pdf/of99-522.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/1999/0522/pdf/of99-522.pdf"><span>A physically-based <span class="hlt">earthquake</span> recurrence <span class="hlt">model</span> for estimation of long-term <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>Ellsworth, William L.; Matthews, Mark V.; Nadeau, Robert M.; Nishenko, Stuart P.; Reasenberg, Paul A.; Simpson, Robert W.</p> <p>1999-01-01</p> <p>A physically-motivated <span class="hlt">model</span> for <span class="hlt">earthquake</span> recurrence based on the Brownian relaxation oscillator is introduced. The renewal process defining this point process <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">earthquakes</span>, 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 <span class="hlt">model</span> to the next M 6 <span class="hlt">earthquake</span> on the San Andreas fault at Parkfield, California suggests that the annual probability of the <span class="hlt">earthquake</span> is between 1:10 and 1:13.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..1512925V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..1512925V"><span><span class="hlt">Modeling</span> <span class="hlt">earthquake</span> activity using a memristor-based cellular grid</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vourkas, Ioannis; Sirakoulis, Georgios Ch.</p> <p>2013-04-01</p> <p><span class="hlt">Earthquakes</span> are absolutely among the most devastating natural phenomena because of their immediate and long-term severe consequences. <span class="hlt">Earthquake</span> activity <span class="hlt">modeling</span>, especially in areas known to experience frequent large <span class="hlt">earthquakes</span>, could lead to improvements in infrastructure development that will prevent possible loss of lives and property damage. An <span class="hlt">earthquake</span> process is inherently a nonlinear complex system and lately scientists have become interested in finding possible analogues of <span class="hlt">earthquake</span> dynamics. The majority of the <span class="hlt">models</span> developed so far were based on a mass-spring <span class="hlt">model</span> of either one or two dimensions. An early approach towards the reordering and the improvement of existing <span class="hlt">models</span> presenting the capacitor-inductor (LC) analogue, where the LC circuit resembles a mass-spring system and simulates <span class="hlt">earthquake</span> activity, was also published recently. Electromagnetic oscillation occurs when energy is transferred between the capacitor and the inductor. This energy transformation is similar to the mechanical oscillation that takes place in the mass-spring system. A few years ago memristor-based oscillators were used as learning circuits exposed to a train of voltage pulses that mimic environment changes. The mathematical foundation of the memristor (memory resistor), as the fourth fundamental passive element, has been expounded by Leon Chua and later extended to a more broad class of memristors, known as memristive devices and systems. This class of two-terminal passive circuit elements with memory performs both information processing and storing of computational data on the same physical platform. Importantly, the states of these devices adjust to input signals and provide analog capabilities unavailable in standard circuit elements, resulting in adaptive circuitry and providing analog parallel computation. In this work, a memristor-based cellular grid is used to <span class="hlt">model</span> <span class="hlt">earthquake</span> activity. An LC contour along with a memristor is used to <span class="hlt">model</span> seismic activity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMED43E..06F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMED43E..06F"><span>Visible <span class="hlt">Earthquakes</span>: a web-based tool for visualizing and <span class="hlt">modeling</span> InSAR <span class="hlt">earthquake</span> data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Funning, G. J.; Cockett, R.</p> <p>2012-12-01</p> <p>InSAR (Interferometric Synthetic Aperture Radar) is a technique for measuring the deformation of the ground using satellite radar data. One of the principal applications of this method is in the study of <span class="hlt">earthquakes</span>; in the past 20 years over 70 <span class="hlt">earthquakes</span> have been studied in this way, and forthcoming satellite missions promise to enable the routine and timely study of events in the future. Despite the utility of the technique and its widespread adoption by the research community, InSAR does not feature in the teaching curricula of most university geoscience departments. This is, we believe, due to a lack of accessibility to software and data. Existing tools for the visualization and <span class="hlt">modeling</span> of interferograms are often research-oriented, command line-based and/or prohibitively expensive. Here we present a new web-based interactive tool for comparing real InSAR data with simple elastic <span class="hlt">models</span>. The overall design of this tool was focused on ease of access and use. This tool should allow interested nonspecialists to gain a feel for the use of such data and greatly facilitate integration of InSAR into upper division geoscience courses, giving students practice in comparing actual data to <span class="hlt">modeled</span> results. The tool, provisionally named 'Visible <span class="hlt">Earthquakes</span>', uses web-based technologies to instantly render the displacement field that would be observable using InSAR for a given fault location, geometry, orientation, and slip. The user can adjust these 'source parameters' using a simple, clickable interface, and see how these affect the resulting <span class="hlt">model</span> interferogram. By visually matching the <span class="hlt">model</span> interferogram to a real <span class="hlt">earthquake</span> interferogram (processed separately and included in the web tool) a user can produce their own estimates of the <span class="hlt">earthquake</span>'s source parameters. Once satisfied with the fit of their <span class="hlt">models</span>, users can submit their results and see how they compare with the distribution of all other contributed <span class="hlt">earthquake</span> <span class="hlt">models</span>, as well as the mean and median</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.202...17R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.202...17R"><span>Quantifying variability in <span class="hlt">earthquake</span> rupture <span class="hlt">models</span> using multidimensional scaling: application 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>Razafindrakoto, Hoby N. T.; Mai, P. Martin; Genton, Marc G.; Zhang, Ling; Thingbaijam, Kiran K. S.</p> <p>2015-07-01</p> <p>Finite-fault <span class="hlt">earthquake</span> source inversion is an ill-posed inverse problem leading to non-unique solutions. In addition, various fault parametrizations and input data may have been used by different researchers for the same <span class="hlt">earthquake</span>. Such variability leads to large intra-event variability in the inferred rupture <span class="hlt">models</span>. One way to understand this problem is to develop robust metrics to quantify <span class="hlt">model</span> variability. We propose a Multi Dimensional Scaling (MDS) approach to compare rupture <span class="hlt">models</span> quantitatively. We consider normalized squared and grey-scale metrics that reflect the variability in the location, intensity and geometry of the source parameters. We test the approach on two-dimensional random fields generated using a von Kármán autocorrelation function and varying its spectral parameters. The spread of points in the MDS solution indicates different levels of <span class="hlt">model</span> variability. We observe that the normalized squared metric is insensitive to variability of spectral parameters, whereas the grey-scale metric is sensitive to small-scale changes in geometry. From this benchmark, we formulate a similarity scale to rank the rupture <span class="hlt">models</span>. As case studies, we examine inverted <span class="hlt">models</span> from the Source Inversion Validation (SIV) exercise and published <span class="hlt">models</span> of the 2011 Mw 9.0 Tohoku <span class="hlt">earthquake</span>, allowing us to test our approach for a case with a known reference <span class="hlt">model</span> and one with an unknown true solution. The normalized squared and grey-scale metrics are respectively sensitive to the overall intensity and the extension of the three classes of slip (very large, large, and low). Additionally, we observe that a three-dimensional MDS configuration is preferable for <span class="hlt">models</span> with large variability. We also find that the <span class="hlt">models</span> for the Tohoku <span class="hlt">earthquake</span> derived from tsunami data and their corresponding predictions cluster with a systematic deviation from other <span class="hlt">models</span>. We demonstrate the stability of the MDS point-cloud using a number of realizations and jackknife tests, for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GeoJI.200..185Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GeoJI.200..185Z"><span>Analysing <span class="hlt">earthquake</span> slip <span class="hlt">models</span> with the spatial prediction comparison test</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Ling; Mai, P. Martin; Thingbaijam, Kiran K. S.; Razafindrakoto, Hoby N. T.; Genton, Marc G.</p> <p>2015-01-01</p> <p><span class="hlt">Earthquake</span> rupture <span class="hlt">models</span> inferred from inversions of geophysical and/or geodetic data exhibit remarkable variability due to uncertainties in <span class="hlt">modelling</span> assumptions, the use of different inversion algorithms, or variations in data selection and data processing. A robust statistical comparison of different rupture <span class="hlt">models</span> obtained for a single <span class="hlt">earthquake</span> is needed to quantify the intra-event variability, both for benchmark exercises and for real <span class="hlt">earthquakes</span>. The same approach may be useful to characterize (dis-)similarities in events that are typically grouped into a common class of events (e.g. moderate-size crustal strike-slip <span class="hlt">earthquakes</span> or tsunamigenic large subduction <span class="hlt">earthquakes</span>). For this purpose, we examine the performance of the spatial prediction comparison test (SPCT), a statistical test developed to compare spatial (random) fields by means of a chosen loss function that describes an error relation between a 2-D field (`<span class="hlt">model</span>') and a reference <span class="hlt">model</span>. We implement and calibrate the SPCT approach for a suite of synthetic 2-D slip distributions, generated as spatial random fields with various characteristics, and then apply the method to results of a benchmark inversion exercise with known solution. We find the SPCT to be sensitive to different spatial correlations lengths, and different heterogeneity levels of the slip distributions. The SPCT approach proves to be a simple and effective tool for ranking the slip <span class="hlt">models</span> with respect to a reference <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JPhCS.855a2033P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhCS.855a2033P"><span>Self-exciting point process in <span class="hlt">modeling</span> <span class="hlt">earthquake</span> occurrences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pratiwi, H.; Slamet, I.; Saputro, D. R. S.; Respatiwulan</p> <p>2017-06-01</p> <p>In this paper, we present a procedure for <span class="hlt">modeling</span> <span class="hlt">earthquake</span> based on spatial-temporal point process. The magnitude distribution is expressed as truncated exponential and the event frequency is <span class="hlt">modeled</span> with a spatial-temporal point process that is characterized uniquely by its associated conditional intensity process. The <span class="hlt">earthquakes</span> can be regarded as point patterns that have a temporal clustering feature so we use self-exciting point process for <span class="hlt">modeling</span> the conditional intensity function. The choice of main shocks is conducted via window algorithm by Gardner and Knopoff and the <span class="hlt">model</span> can be fitted by maximum likelihood method for three random variables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PhRvL..89n2502Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PhRvL..89n2502Z"><span>Isobaric Multiplet Yrast Energies and Isospin <span class="hlt">Nonconserving</span> Forces</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zuker, A. P.; Lenzi, S. M.; Martínez-Pinedo, G.; Poves, A.</p> <p>2002-09-01</p> <p>The isovector and isotensor energy differences between yrast states of isobaric multiplets in the lower half of the pf region are quantitatively reproduced in a shell <span class="hlt">model</span> context. The isospin <span class="hlt">nonconserving</span> nuclear interactions are found to be at least as important as the Coulomb potential. Their isovector and isotensor channels are dominated by J=2 and J=0 pairing terms, respectively. The results are sensitive to the radii of the states, whose evolution along the yrast band can be accurately followed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18789709','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18789709"><span>Artificial neural network <span class="hlt">model</span> for <span class="hlt">earthquake</span> prediction with radon monitoring.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Külahci, Fatih; Inceöz, Murat; Doğru, Mahmut; Aksoy, Ercan; Baykara, Oktay</p> <p>2009-01-01</p> <p>Apart from the linear monitoring studies concerning the relationship between radon and <span class="hlt">earthquake</span>, an artificial neural networks (ANNs) <span class="hlt">model</span> approach is presented starting out from non-linear changes of the eight different parameters during the <span class="hlt">earthquake</span> occurrence. A three-layer Levenberg-Marquardt feedforward learning algorithm is used to <span class="hlt">model</span> the <span class="hlt">earthquake</span> prediction process in the East Anatolian Fault System (EAFS). The proposed ANN system employs individual training strategy with fixed-weight and supervised <span class="hlt">models</span> leading to estimations. The average relative error between the magnitudes of the <span class="hlt">earthquakes</span> acquired by ANN and measured data is about 2.3%. The relative error between the test and <span class="hlt">earthquake</span> data varies between 0% and 12%. In addition, the factor analysis was applied on all data and the <span class="hlt">model</span> output values to see the statistical variation. The total variance of 80.18% was explained with four factors by this analysis. Consequently, it can be concluded that ANN approach is a potential alternative to other <span class="hlt">models</span> with complex mathematical operations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70003714','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70003714"><span>An empirical <span class="hlt">model</span> 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 rates of <span class="hlt">earthquakes</span> worldwide and developed a country/region-specific empirical <span class="hlt">model</span> 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 rate 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 rates for that level and then summing them at all relevant shaking intensities. The fatality rate 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. [DOI: 10.1193/1.3480331</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204..440R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204..440R"><span>Retrospective tests of hybrid operational <span class="hlt">earthquake</span> forecasting <span class="hlt">models</span> for Canterbury</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rhoades, D. A.; Liukis, M.; Christophersen, A.; Gerstenberger, M. C.</p> <p>2016-01-01</p> <p>The Canterbury, New Zealand, <span class="hlt">earthquake</span> sequence, which began in September 2010, occurred in a region of low crustal deformation and previously low seismicity. Because, the ensuing seismicity in the region is likely to remain above previous levels for many years, a hybrid operational <span class="hlt">earthquake</span> forecasting <span class="hlt">model</span> for Canterbury was developed to inform decisions on building standards and urban planning for the rebuilding of Christchurch. The <span class="hlt">model</span> estimates occurrence probabilities for magnitudes M ≥ 5.0 in the Canterbury region for each of the next 50 yr. It combines two short-term, two medium-term and four long-term forecasting <span class="hlt">models</span>. The weight accorded to each individual <span class="hlt">model</span> in the operational hybrid was determined by an expert elicitation process. A retrospective test of the operational hybrid <span class="hlt">model</span> and of an earlier informally developed hybrid <span class="hlt">model</span> in the whole New Zealand region has been carried out. The individual and hybrid <span class="hlt">models</span> were installed in the New Zealand <span class="hlt">Earthquake</span> Forecast Testing Centre and used to make retrospective annual forecasts of <span class="hlt">earthquakes</span> with magnitude M > 4.95 from 1986 on, for time-lags up to 25 yr. All <span class="hlt">models</span> underpredict the number of <span class="hlt">earthquakes</span> due to an abnormally large number of <span class="hlt">earthquakes</span> in the testing period since 2008 compared to those in the learning period. However, the operational hybrid <span class="hlt">model</span> is more informative than any of the individual time-varying <span class="hlt">models</span> for nearly all time-lags. Its information gain relative to a reference <span class="hlt">model</span> of least information decreases as the time-lag increases to become zero at a time-lag of about 20 yr. An optimal hybrid <span class="hlt">model</span> with the same mathematical form as the operational hybrid <span class="hlt">model</span> was computed for each time-lag from the 26-yr test period. The time-varying component of the optimal hybrid is dominated by the medium-term <span class="hlt">models</span> for time-lags up to 12 yr and has hardly any impact on the optimal hybrid <span class="hlt">model</span> for greater time-lags. The optimal hybrid <span class="hlt">model</span> is considerably more</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/8899','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/8899"><span><span class="hlt">Modeling</span> the behavior of an <span class="hlt">earthquake</span> base-isolated building.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Coveney, V. A.; Jamil, S.; Johnson, D. E.; Kulak, R. F.; Uras, R. A.</p> <p>1997-11-26</p> <p>Protecting a structure against <span class="hlt">earthquake</span> excitation by supporting it on laminated elastomeric bearings has become a widely accepted practice. The ability to perform accurate simulation of the system, including FEA of the bearings, would be desirable--especially for key installations. In this paper attempts to <span class="hlt">model</span> the behavior of elastomeric <span class="hlt">earthquake</span> bearings are outlined. Attention is focused on <span class="hlt">modeling</span> highly-filled, low-modulus, high-damping elastomeric isolator systems; comparisons are made between standard triboelastic solid <span class="hlt">model</span> predictions and test results.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016DDA....4710303T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016DDA....4710303T"><span>Slimplectic Integrators: Variational Integrators for <span class="hlt">Nonconservative</span> systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsang, David</p> <p>2016-05-01</p> <p>Symplectic integrators are widely used for long-term integration of conservative astrophysical problems due to their ability to preserve the constants of motion; however, they cannot in general be applied in the presence of <span class="hlt">nonconservative</span> interactions. Here we present the “slimplectic” integrator, a new type of numerical integrator that shares many of the benefits of traditional symplectic integrators yet is applicable to general <span class="hlt">nonconservative</span> systems. We utilize a fixed-time-step variational integrator formalism applied to a newly developed principle of stationary <span class="hlt">nonconservative</span> action (Galley, 2013, Galley et al 2014). As a result, the generalized momenta and energy (Noether current) evolutions are well-tracked. We discuss several example systems, including damped harmonic oscillators, Poynting-Robertson drag, and gravitational radiation reaction, by utilizing our new publicly available code to demonstrate the slimplectic integrator algorithm. Slimplectic integrators are well-suited for integrations of systems where <span class="hlt">nonconservative</span> effects play an important role in the long-term dynamical evolution. As such they are particularly appropriate for cosmological or celestial N-body dynamics problems where <span class="hlt">nonconservative</span> interactions, e.g., gas interactions or dissipative tides, can play an important role.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2000PhDT.......130T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2000PhDT.......130T"><span><span class="hlt">Modeling</span> of <span class="hlt">earthquake</span> ground motion in the frequency domain</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thrainsson, Hjortur</p> <p></p> <p>In recent years, the utilization of time histories of <span class="hlt">earthquake</span> ground motion has grown considerably in the design and analysis of civil structures. It is very unlikely, however, that recordings of <span class="hlt">earthquake</span> ground motion will be available for all sites and conditions of interest. Hence, there is a need for efficient methods for the simulation and spatial interpolation of <span class="hlt">earthquake</span> ground motion. In addition to providing estimates of the ground motion at a site using data from adjacent recording stations, spatially interpolated ground motions can also be used in design and analysis of long-span structures, such as bridges and pipelines, where differential movement is important. The objective of this research is to develop a methodology for rapid generation of horizontal <span class="hlt">earthquake</span> ground motion at any site for a given region, based on readily available source, path and site characteristics, or (sparse) recordings. The research includes two main topics: (i) the simulation of <span class="hlt">earthquake</span> ground motion at a given site, and (ii) the spatial interpolation of <span class="hlt">earthquake</span> ground motion. In topic (i), <span class="hlt">models</span> are developed to simulate acceleration time histories using the inverse discrete Fourier transform. The Fourier phase differences, defined as the difference in phase angle between adjacent frequency components, are simulated conditional on the Fourier amplitude. Uniformly processed recordings from recent California <span class="hlt">earthquakes</span> are used to validate the simulation <span class="hlt">models</span>, as well as to develop prediction formulas for the <span class="hlt">model</span> parameters. The <span class="hlt">models</span> developed in this research provide rapid simulation of <span class="hlt">earthquake</span> ground motion over a wide range of magnitudes and distances, but they are not intended to replace more robust geophysical <span class="hlt">models</span>. In topic (ii), a <span class="hlt">model</span> is developed in which Fourier amplitudes and Fourier phase angles are interpolated separately. A simple dispersion relationship is included in the phase angle interpolation. The accuracy of the interpolation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174.3237T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174.3237T"><span>Method to Determine Appropriate Source <span class="hlt">Models</span> of Large <span class="hlt">Earthquakes</span> Including Tsunami <span class="hlt">Earthquakes</span> for Tsunami Early Warning in Central America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tanioka, Yuichiro; Miranda, Greyving Jose Arguello; Gusman, Aditya Riadi; Fujii, Yushiro</p> <p>2017-08-01</p> <p>Large <span class="hlt">earthquakes</span>, such as the Mw 7.7 1992 Nicaragua <span class="hlt">earthquake</span>, have occurred off the Pacific coasts of El Salvador and Nicaragua in Central America and have generated distractive tsunamis along these coasts. It is necessary to determine appropriate fault <span class="hlt">models</span> before large tsunamis hit the coast. In this study, first, fault parameters were estimated from the W-phase inversion, and then an appropriate fault <span class="hlt">model</span> was determined from the fault parameters and scaling relationships with a depth dependent rigidity. The method was tested for four large <span class="hlt">earthquakes</span>, the 1992 Nicaragua tsunami <span class="hlt">earthquake</span> (Mw7.7), the 2001 El Salvador <span class="hlt">earthquake</span> (Mw7.7), the 2004 El Astillero <span class="hlt">earthquake</span> (Mw7.0), and the 2012 El Salvador-Nicaragua <span class="hlt">earthquake</span> (Mw7.3), which occurred off El Salvador and Nicaragua in Central America. The tsunami numerical simulations were carried out from the determined fault <span class="hlt">models</span>. We found that the observed tsunami heights, run-up heights, and inundation areas were reasonably well explained by the computed ones. Therefore, our method for tsunami early warning purpose should work to estimate a fault <span class="hlt">model</span> which reproduces tsunami heights near the coast of El Salvador and Nicaragua due to large <span class="hlt">earthquakes</span> in the subduction zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812412Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812412Z"><span>Assessing a 3D smoothed seismicity <span class="hlt">model</span> of induced <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>Zechar, Jeremy; Király, Eszter; Gischig, Valentin; Wiemer, Stefan</p> <p>2016-04-01</p> <p>As more energy exploration and extraction efforts cause <span class="hlt">earthquakes</span>, it becomes increasingly important to control induced seismicity. Risk management schemes must be improved and should ultimately be based on near-real-time forecasting systems. With this goal in mind, we propose a test bench to evaluate <span class="hlt">models</span> of induced seismicity based on metrics developed by the CSEP community. To illustrate the test bench, we consider a <span class="hlt">model</span> based on the so-called seismogenic index and a rate decay; to produce three-dimensional forecasts, we smooth past <span class="hlt">earthquakes</span> in space and time. We explore four variants of this <span class="hlt">model</span> using the Basel 2006 and Soultz-sous-Forêts 2004 datasets to make short-term forecasts, test their consistency, and rank the <span class="hlt">model</span> variants. Our results suggest that such a smoothed seismicity <span class="hlt">model</span> is useful for forecasting induced seismicity within three days, and giving more weight to recent events improves forecast performance. Moreover, the location of the largest induced <span class="hlt">earthquake</span> is forecast well by this <span class="hlt">model</span>. Despite the good spatial performance, the <span class="hlt">model</span> does not estimate the seismicity rate well: it frequently overestimates during stimulation and during the early post-stimulation period, and it systematically underestimates around shut-in. In this presentation, we also describe a robust estimate of information gain, a modification that can also benefit forecast experiments involving tectonic <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1245421','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1245421"><span>Computer program for generating kinematic <span class="hlt">earthquake</span> rupture <span class="hlt">models</span> using Irikura and Miyake's method.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pitarka, Arben</p> <p>2016-02-10</p> <p>GEN_SRF_4 is a computer program for generation kinematic <span class="hlt">earthquake</span> rupture <span class="hlt">models</span> for use in ground motion <span class="hlt">modeling</span> and simulations of <span class="hlt">earthquakes</span>. The output is an ascii SRF formatted file containing kinematic rupture parameters.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.S42B..03P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.S42B..03P"><span><span class="hlt">Model</span> Uncertainty, <span class="hlt">Earthquake</span> Hazard, and the WGCEP-2002 Forecast</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Page, M. T.; Carlson, J. M.</p> <p>2005-12-01</p> <p><span class="hlt">Model</span> uncertainty is prevalent in Probabilistic Seismic Hazard Analysis (PSHA) because the true mechanism generating risk is unknown. While it is well-understood how to incorporate parameter uncertainty in PSHA, <span class="hlt">model</span> uncertainty is more difficult to incorporate due to the high degree of dependence between different <span class="hlt">earthquake</span>-recurrence <span class="hlt">models</span>. We find that the method used by the 2002 Working Group on California <span class="hlt">Earthquake</span> Probabilities (WG02) to combine the probability distributions given by multiple <span class="hlt">models</span> has several adverse effects on their result. In particular, taking a linear combination of the various <span class="hlt">models</span> ignores issues of <span class="hlt">model</span> dependence and leads to large uncertainties in the final hazard estimate. Furthermore, choosing <span class="hlt">model</span> weights based on data can systematically bias the final probability distribution. The weighting scheme of the WG02 report also depends upon an arbitrary ordering of <span class="hlt">models</span>. In addition to analyzing current statistical problems, we present alternative methods for rigorously incorporating <span class="hlt">model</span> uncertainty into PSHA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMNG51A1196D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMNG51A1196D"><span><span class="hlt">Earthquake</span> nucleation mechanisms and periodic loading: <span class="hlt">Models</span>, Experiments, and Observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dahmen, K.; Brinkman, B.; Tsekenis, G.; Ben-Zion, Y.; Uhl, J.</p> <p>2010-12-01</p> <p>The project has two main goals: (a) Improve the understanding of how <span class="hlt">earthquakes</span> are nucleated ¬ with specific focus on seismic response to periodic stresses (such as tidal or seasonal variations) (b) Use the results of (a) to infer on the possible existence of precursory activity before large <span class="hlt">earthquakes</span>. A number of mechanisms have been proposed for the nucleation of <span class="hlt">earthquakes</span>, including frictional nucleation (Dieterich 1987) and fracture (Lockner 1999, Beeler 2003). We study the relation between the observed rates of triggered seismicity, the period and amplitude of cyclic loadings and whether the observed seismic activity in response to periodic stresses can be used to identify the correct nucleation mechanism (or combination of mechanisms). A generalized version of the Ben-Zion and Rice <span class="hlt">model</span> for disordered fault zones and results from related recent studies on dislocation dynamics and magnetization avalanches in slowly magnetized materials are used in the analysis (Ben-Zion et al. 2010; Dahmen et al. 2009). The analysis makes predictions for the statistics of macroscopic failure events of sheared materials in the presence of added cyclic loading, as a function of the period, amplitude, and noise in the system. The employed tools include analytical methods from statistical physics, the theory of phase transitions, and numerical simulations. The results will be compared to laboratory experiments and observations. References: Beeler, N.M., D.A. Lockner (2003). Why <span class="hlt">earthquakes</span> correlate weakly with the solid Earth tides: effects of periodic stress on the rate and probability of <span class="hlt">earthquake</span> occurrence. J. Geophys. Res.-Solid Earth 108, 2391-2407. Ben-Zion, Y. (2008). Collective Behavior of <span class="hlt">Earthquakes</span> and Faults: Continuum-Discrete Transitions, Evolutionary Changes and Corresponding Dynamic Regimes, Rev. Geophysics, 46, RG4006, doi:10.1029/2008RG000260. Ben-Zion, Y., Dahmen, K. A. and J. T. Uhl (2010). A unifying phase diagram for the dynamics of sheared solids</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S31B2755M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S31B2755M"><span><span class="hlt">Modeling</span> the Fluid Withdraw and Injection Induced <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>Meng, C.</p> <p>2016-12-01</p> <p>We present an open source numerical code, Defmod, that allows one to <span class="hlt">model</span> the induced seismicity in an efficient and standalone manner. The fluid withdraw and injection induced <span class="hlt">earthquake</span> has been a great concern to the industries including oil/gas, wastewater disposal and CO2 sequestration. Being able to numerically <span class="hlt">model</span> the induced seismicity is long desired. To do that, one has to consider at lease two processes, a steady process that describes the inducing and aseismic stages before and in between the seismic events, and an abrupt process that describes the dynamic fault rupture accompanied by seismic energy radiations during the events. The steady process can be adequately <span class="hlt">modeled</span> by a quasi-static <span class="hlt">model</span>, while the abrupt process has to be <span class="hlt">modeled</span> by a dynamic <span class="hlt">model</span>. In most of the published <span class="hlt">modeling</span> works, only one of these processes is considered. The geomechanicists and reservoir engineers are focused more on the quasi-static <span class="hlt">modeling</span>, whereas the geophysicists and seismologists are focused more on the dynamic <span class="hlt">modeling</span>. The finite element code Defmod combines these two <span class="hlt">models</span> into a hybrid <span class="hlt">model</span> that uses the failure criterion and frictional laws to adaptively switch between the (quasi-)static and dynamic states. The code is capable of <span class="hlt">modeling</span> episodic fault rupture driven by quasi-static loading, e.g. due to reservoir fluid withdraw and/or injection, and by dynamic loading, e.g. due to the foregoing <span class="hlt">earthquakes</span>. We demonstrate a case study for the 2013 Azle <span class="hlt">earthquake</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_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('http://adsabs.harvard.edu/abs/2011AGUFM.S22B..05W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S22B..05W"><span>Numerical <span class="hlt">modeling</span> of shallow fault creep triggered by 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>Wei, M.; Liu, Y.; McGuire, J. J.</p> <p>2011-12-01</p> <p>The 2010 El Mayor-Cucapha Mw 7.2 <span class="hlt">earthquake</span> is the largest <span class="hlt">earthquake</span> that strikes southern California in the last 18 years. It has triggered shallow fault creep on many faults in Salton Trough, Southern California, making it at least the 8th time in the last 42 years that a local or regional <span class="hlt">earthquake</span> has done so. However, the triggering mechanism of fault creep and its implications to seismic hazard and fault mechanics is still poorly understood. For example, what determines the relative importance of static triggering and dynamic triggering of fault creep? What can we learn about the local frictional properties and normal stress from the triggering of fault creep? To understand the triggering mechanism and constrain fault frictional properties, we simulate the triggered fault creep on the Superstition Hills Fault (SHF), Salton Trough, Southern California. We use realistic static and dynamic shaking due to nearby <span class="hlt">earthquakes</span> as stress perturbations to a 2D (in a 3D medium) planar fault <span class="hlt">model</span> with rate-and-state frictional property variations both in depth and along strike. Unlike many previous studies, we focus on the simulation of triggered shallow fault creep instead of <span class="hlt">earthquakes</span>. Our fault <span class="hlt">model</span> can reproduce the triggering process, by static, dynamic , and combined stress perturbation. Preliminary results show that the magnitude of perturbation relative to the original stress level is an important parameter. In the static case, perturbation of 1% of normal stress trigger delayed fault creep whereas 10% of normal stress generate instantaneous creep. In the dynamic case, a change of two times in magnitude of perturbation can result in difference of triggered creep in several orders of magnitude. We explore combined triggering with different ratio of static and dynamic perturbation. The timing of triggering in a <span class="hlt">earthquake</span> cycle is also important. With measurements on triggered creep on the SHF, we constrain local stress level and frictional parameters, which</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70157353','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70157353"><span>Dynamic <span class="hlt">models</span> of an <span class="hlt">earthquake</span> and tsunami offshore Ventura, 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>Kenny J. Ryan,; Geist, Eric L.; Barall, Michael; David D. Oglesby,</p> <p>2015-01-01</p> <p>The Ventura basin in Southern California includes coastal dip-slip faults that can likely produce <span class="hlt">earthquakes</span> of magnitude 7 or greater and significant local tsunamis. We construct a 3-D dynamic rupture <span class="hlt">model</span> of an <span class="hlt">earthquake</span> on the Pitas Point and Lower Red Mountain faults to <span class="hlt">model</span> low-frequency ground motion and the resulting tsunami, with a goal of elucidating the seismic and tsunami hazard in this area. Our <span class="hlt">model</span> results in an average stress drop of 6 MPa, an average fault slip of 7.4 m, and a moment magnitude of 7.7, consistent with regional paleoseismic data. Our corresponding tsunami <span class="hlt">model</span> uses final seafloor displacement from the rupture <span class="hlt">model</span> as initial conditions to compute local propagation and inundation, resulting in large peak tsunami amplitudes northward and eastward due to site and path effects. <span class="hlt">Modeled</span> inundation in the Ventura area is significantly greater than that indicated by state of California's current reference inundation line.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1730b0005W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1730b0005W"><span>Prediction <span class="hlt">model</span> of <span class="hlt">earthquake</span> with the identification of <span class="hlt">earthquake</span> source polarity mechanism through the focal classification using ANFIS and PCA technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Setyonegoro, W.</p> <p>2016-05-01</p> <p>Incidence of <span class="hlt">earthquake</span> disaster has caused casualties and material in considerable amounts. This research has purposes to predictability the return period of <span class="hlt">earthquake</span> with the identification of the mechanism of <span class="hlt">earthquake</span> which in case study area in Sumatra. To predict <span class="hlt">earthquakes</span> which training data of the historical <span class="hlt">earthquake</span> is using ANFIS technique. In this technique the historical data set compiled into intervals of <span class="hlt">earthquake</span> occurrence daily average in a year. Output to be obtained is a <span class="hlt">model</span> return period <span class="hlt">earthquake</span> events daily average in a year. Return period <span class="hlt">earthquake</span> occurrence <span class="hlt">models</span> that have been learning by ANFIS, then performed the polarity recognition through image recognition techniques on the focal sphere using principal component analysis PCA method. The results, <span class="hlt">model</span> predicted a return period <span class="hlt">earthquake</span> events for the average monthly return period showed a correlation coefficient 0.014562.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=history+AND+atomic+AND+theory&pg=4&id=EJ241200','ERIC'); return false;" href="http://eric.ed.gov/?q=history+AND+atomic+AND+theory&pg=4&id=EJ241200"><span>Justification of a "Crucial" Experiment: Parity <span class="hlt">Nonconservation</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>Franklin, Allan; Smokler, Howard</p> <p>1981-01-01</p> <p>Presents history, nature of evidence evaluated, and philosophical questions to justify the view that experiments on parity <span class="hlt">nonconservation</span> were "crucial" experiments in the sense that they decided unambiguously and within a short period of time for the appropriate scientific community, between two or more competing theories or classes of theories.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=fluid+AND+mechanics&pg=5&id=EJ755173','ERIC'); return false;" href="http://eric.ed.gov/?q=fluid+AND+mechanics&pg=5&id=EJ755173"><span>The Common Forces: Conservative or <span class="hlt">Nonconservative</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>Keeports, David</p> <p>2006-01-01</p> <p>Of the forces commonly encountered when solving problems in Newtonian mechanics, introductory texts usually limit illustrations of the definitions of conservative and <span class="hlt">nonconservative</span> forces to gravity, spring forces, kinetic friction and fluid resistance. However, at the expense of very little class time, the question of whether each of the common…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=history+AND+atomic+AND+theory&pg=4&id=EJ241200','ERIC'); return false;" href="https://eric.ed.gov/?q=history+AND+atomic+AND+theory&pg=4&id=EJ241200"><span>Justification of a "Crucial" Experiment: Parity <span class="hlt">Nonconservation</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>Franklin, Allan; Smokler, Howard</p> <p>1981-01-01</p> <p>Presents history, nature of evidence evaluated, and philosophical questions to justify the view that experiments on parity <span class="hlt">nonconservation</span> were "crucial" experiments in the sense that they decided unambiguously and within a short period of time for the appropriate scientific community, between two or more competing theories or classes of theories.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=fluid+AND+mechanics&pg=6&id=EJ755173','ERIC'); return false;" href="https://eric.ed.gov/?q=fluid+AND+mechanics&pg=6&id=EJ755173"><span>The Common Forces: Conservative or <span class="hlt">Nonconservative</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>Keeports, David</p> <p>2006-01-01</p> <p>Of the forces commonly encountered when solving problems in Newtonian mechanics, introductory texts usually limit illustrations of the definitions of conservative and <span class="hlt">nonconservative</span> forces to gravity, spring forces, kinetic friction and fluid resistance. However, at the expense of very little class time, the question of whether each of the common…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S21A2686T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S21A2686T"><span>CSEP Evaluations of 24-Hour <span class="hlt">Earthquake</span> Forecasting <span class="hlt">Models</span> for California: New Results and Ensemble <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Taroni, M.; Werner, M. J.; Liukis, M.; Marzocchi, W.; Rhoades, D. A.; Zechar, J. D.; Jordan, T. H.</p> <p>2016-12-01</p> <p>Operational <span class="hlt">Earthquake</span> Forecasting requires reliable and validated <span class="hlt">earthquake</span> probability estimates at short time scales. The objective of the Collaboratory for the Study of <span class="hlt">Earthquake</span> Predictability (CSEP) is to evaluate <span class="hlt">earthquake</span> forecasting <span class="hlt">models</span> and hypotheses in a blind, automated and prospective manner. CSEP supports OEF efforts by independently and rigorously evaluating the strengths and weaknesses of candidate OEF <span class="hlt">models</span> and ensemble OEF <span class="hlt">models</span>. CSEP has been evaluating over a dozen 24-hour forecasting <span class="hlt">models</span> in California since 2009. <span class="hlt">Models</span> include the STEP <span class="hlt">model</span>, various ETAS <span class="hlt">model</span> flavors, non-parametric <span class="hlt">models</span> and other statistical clustered seismicity <span class="hlt">models</span>. Here, we report on new results from CSEP's 24-hour <span class="hlt">earthquake</span> forecasting experiment in California. The data set consists of 132 <span class="hlt">earthquakes</span> greater than magnitude 3.95. Relative probability gains indicate that the predictive skills of the recent <span class="hlt">models</span> are improving. This suggests progress in <span class="hlt">modelling</span> future <span class="hlt">earthquake</span> potential. In addition, we explore protocols for constructing ensemble <span class="hlt">models</span>. These are a powerful forecasting tool when several informative <span class="hlt">models</span> are available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060040306&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DEarthquake','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060040306&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3DEarthquake"><span>Combined GPS and InSAR <span class="hlt">models</span> of postseismic deformation from the Northridge <span class="hlt">Earthquake</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Donnellan, A.; Parker, J. W.; Peltzer, G.</p> <p>2002-01-01</p> <p><span class="hlt">Models</span> of combined Global Positioning System and Interferometric Synthetic Aperture Radar data collected in the region of the Northridge <span class="hlt">earthquake</span> indicate that significant afterslip on the main fault occurred following the <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988JGR....93.6255R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988JGR....93.6255R"><span>A physical <span class="hlt">model</span> for <span class="hlt">earthquakes</span>: 2. Application to southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rundle, John B.</p> <p>1988-06-01</p> <p>The purpose of this paper is to apply ideas developed in a previous paper to the construction of a detailed <span class="hlt">model</span> for <span class="hlt">earthquake</span> dynamics in southern California. The basis upon which the approach is formulated is that <span class="hlt">earthquakes</span> are perturbations on, or more specifically fluctuations about, the long-term motions of the plates. This concept is made mathematically precise by means of a "fluctuation hypothesis," which states that all physical quantities associated with <span class="hlt">earthquakes</span> can be expressed as integral expansions in a fluctuating quantity called the "offset phase." While in general, the frictional stick-slip properties of the complex, interacting faults should properly come out of the underlying physics, a simplification is made here, and a simple, spatially varying friction law is assumed. Together with the complex geometry of the major active faults, an assumed, spatially varying Earth rheology, the average rates of long-term offsets on all the major faults, and the friction coefficients, one can generate synthetic <span class="hlt">earthquake</span> histories for comparison to the real data. The result is a set of slip-time histories for all of the major faults which are similar to data obtained by geologic trenching studies. However, the patterns of <span class="hlt">earthquake</span> occurrence are evidently chaotic (in the technical sense), meaning that although there is an element of periodicity to the events, the patterns shift, change, and evolve with time. Time scales for pattern evolution seem to be of the order of a thousand years for average recurrance intervals of a hundred years or so. In the synthetic slip histories for the <span class="hlt">model</span> faults a series of events on the Big Bend is identified which resembles the pattern of events leading up to the 1857 Fort Tejon <span class="hlt">earthquake</span>. One of the events is similar enough to the 1857 event that it is taken as a <span class="hlt">model</span> of that <span class="hlt">earthquake</span>. The horizontal surface deformation 130 years after the <span class="hlt">model</span> event is calculated for comparison to the data observed by various</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PApGe.tmp..180L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PApGe.tmp..180L"><span>Stochastic <span class="hlt">Earthquake</span> Rupture <span class="hlt">Modeling</span> Using Nonparametric Co-Regionalization</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lee, Kyungbook; Song, Seok Goo</p> <p>2016-10-01</p> <p>Accurate predictions of the intensity and variability of ground motions are essential in simulation-based seismic hazard assessment. Advanced simulation-based ground motion prediction methods have been proposed to complement the empirical approach, which suffers from the lack of observed ground motion data, especially in the near-source region for large events. It is important to quantify the variability of the <span class="hlt">earthquake</span> rupture process for future events and to produce a number of rupture scenario <span class="hlt">models</span> to capture the variability in simulation-based ground motion predictions. In this study, we improved the previously developed stochastic <span class="hlt">earthquake</span> rupture <span class="hlt">modeling</span> method by applying the nonparametric co-regionalization, which was proposed in geostatistics, to the correlation <span class="hlt">models</span> estimated from dynamically derived <span class="hlt">earthquake</span> rupture <span class="hlt">models</span>. The nonparametric approach adopted in this study is computationally efficient and, therefore, enables us to simulate numerous rupture scenarios, including large events (M > 7.0). It also gives us an opportunity to check the shape of true input correlation <span class="hlt">models</span> in stochastic <span class="hlt">modeling</span> after being deformed for permissibility. We expect that this type of <span class="hlt">modeling</span> will improve our ability to simulate a wide range of rupture scenario <span class="hlt">models</span> and thereby predict ground motions and perform seismic hazard assessment more accurately.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70175400','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70175400"><span>Source <span class="hlt">modeling</span> of the 2015 Mw 7.8 Nepal (Gorkha) <span class="hlt">earthquake</span> sequence: Implications for geodynamics and <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>McNamara, Daniel E.; Yeck, William; Barnhart, William D.; Schulte-Pelkum, V.; Bergman, E.; Adhikari, L. B.; Dixit, Amod; Hough, S.E.; Benz, Harley M.; Earle, Paul</p> <p>2017-01-01</p> <p>The Gorkha <span class="hlt">earthquake</span> on April 25th, 2015 was a long anticipated, low-angle thrust-faulting event on the shallow décollement between the India and Eurasia plates. We present a detailed multiple-event hypocenter relocation analysis of the Mw 7.8 Gorkha Nepal <span class="hlt">earthquake</span> sequence, constrained by local seismic stations, and a geodetic rupture <span class="hlt">model</span> based on InSAR and GPS data. We integrate these observations to place the Gorkha <span class="hlt">earthquake</span> sequence into a seismotectonic context and evaluate potential <span class="hlt">earthquake</span> hazard.Major results from this study include (1) a comprehensive catalog of calibrated hypocenters for the Gorkha <span class="hlt">earthquake</span> sequence; (2) the Gorkha <span class="hlt">earthquake</span> ruptured a ~ 150 × 60 km patch of the Main Himalayan Thrust (MHT), the décollement defining the plate boundary at depth, over an area surrounding but predominantly north of the capital city of Kathmandu (3) the distribution of aftershock seismicity surrounds the mainshock maximum slip patch; (4) aftershocks occur at or below the mainshock rupture plane with depths generally increasing to the north beneath the higher Himalaya, possibly outlining a 10–15 km thick subduction channel between the overriding Eurasian and subducting Indian plates; (5) the largest Mw 7.3 aftershock and the highest concentration of aftershocks occurred to the southeast the mainshock rupture, on a segment of the MHT décollement that was positively stressed towards failure; (6) the near surface portion of the MHT south of Kathmandu shows no aftershocks or slip during the mainshock. Results from this study characterize the details of the Gorkha <span class="hlt">earthquake</span> sequence and provide constraints on where <span class="hlt">earthquake</span> hazard remains high, and thus where future, damaging <span class="hlt">earthquakes</span> may occur in this densely populated region. Up-dip segments of the MHT should be considered to be high hazard for future damaging <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1997PhRvE..56..293R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1997PhRvE..56..293R"><span>Traveling density wave <span class="hlt">models</span> for <span class="hlt">earthquakes</span> and driven threshold systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rundle, John B.; Klein, W.; Gross, Susanna; Ferguson, C. D.</p> <p>1997-07-01</p> <p>Driven threshold systems are now used to <span class="hlt">model</span> sandpiles, <span class="hlt">earthquakes</span>, magnetic depinning transitions, integrate-and-fire neural networks, and driven foams. We analyze a physically motivated <span class="hlt">model</span> which has many of the same properties as the hard threshold <span class="hlt">models</span>, but in which all of the nonequilibrium physics is obtained from a Lyapunov functional. The ideas apply to mean-field systems, and lead to a number of predictions, including scaling exponents and metastable lifetimes for nucleating droplets. The former predictions are supported, for example, by data observed for <span class="hlt">earthquake</span> fault systems. An interesting consequence of the <span class="hlt">model</span> is that time appears as a scaling field, leading to temporal scaling laws similar to those observed in nature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.9147Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.9147Z"><span>Meeting the Challenge of <span class="hlt">Earthquake</span> Risk Globalisation: Towards the Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> GEM (Sergey Soloviev Medal Lecture)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zschau, J.</p> <p>2009-04-01</p> <p><span class="hlt">Earthquake</span> risk, like natural risks in general, has become a highly dynamic and globally interdependent phenomenon. Due to the "urban explosion" in the Third World, an increasingly complex cross linking of critical infrastructure and lifelines in the industrial nations and a growing globalisation of the world's economies, we are presently facing a dramatic increase of our society's vulnerability to <span class="hlt">earthquakes</span> in practically all seismic regions on our globe. Such fast and global changes cannot be captured with conventional <span class="hlt">earthquake</span> risk <span class="hlt">models</span> anymore. The sciences in this field are, therefore, asked to come up with new solutions that are no longer exclusively aiming at the best possible quantification of the present risks but also keep an eye on their changes with time and allow to project these into the future. This does not apply to the vulnerablity component of <span class="hlt">earthquake</span> risk alone, but also to its hazard component which has been realized to be time-dependent, too. The challenges of <span class="hlt">earthquake</span> risk dynamics and -globalisation have recently been accepted by the Global Science Forum of the Organisation for Economic Co-operation and Development (OECD - GSF) who initiated the "Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> (GEM)", a public-private partnership for establishing an independent standard to calculate, monitor and communicate <span class="hlt">earthquake</span> risk globally, raise awareness and promote mitigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39443','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=39443"><span>Slip complexity in dynamic <span class="hlt">models</span> of <span class="hlt">earthquake</span> faults.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Langer, J S; Carlson, J M; Myers, C R; Shaw, B E</p> <p>1996-01-01</p> <p>We summarize recent evidence that <span class="hlt">models</span> of <span class="hlt">earthquake</span> faults with dynamically unstable friction laws but no externally imposed heterogeneities can exhibit slip complexity. Two <span class="hlt">models</span> are described here. The first is a one-dimensional <span class="hlt">model</span> with velocity-weakening stick-slip friction; the second is a two-dimensional elastodynamic <span class="hlt">model</span> with slip-weakening friction. Both exhibit small-event complexity and chaotic sequences of large characteristic events. The large events in both <span class="hlt">models</span> are composed of Heaton pulses. We argue that the key ingredients of these <span class="hlt">models</span> are reasonably accurate representations of the properties of real faults. PMID:11607671</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7188857','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7188857"><span>Physical <span class="hlt">model</span> for <span class="hlt">earthquakes</span>, 2. Application to southern California</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rundle, J.B.</p> <p>1988-06-10</p> <p>The purpose of this paper is to apply ideas developed in a previous paper to the construction of a detailed <span class="hlt">model</span> for <span class="hlt">earthquake</span> dynamics in southern California. The basis upon which the approach is formulated is that <span class="hlt">earthquakes</span> are perturbations on, or more specifically fluctuations about, the long-term motions of the plates. This concept is made mathematically precise by means of a ''fluctuation hypothesis,'' which states that all physical quantities associated with <span class="hlt">earthquakes</span> can be expressed as integral expansions in a fluctuating quantity called the ''offset phase.'' While in general, the frictional stick-slip properties of the complex, interacting faults should properly come out of the underlying physics, a simplification is made here, and a simple, spatially varying friction law is assumed. Together with the complex geometry of the major active faults, an assumed, spatially varying Earth rheology, the average rates of long-term offsets on all the major faults, and the friction coefficients, one can generate synthetic <span class="hlt">earthquake</span> histories for comparison to the real data.</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: <span class="hlt">Modelling</span> <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) <span class="hlt">model</span> and the Coulomb stress change, and implement the seismogenic source parameters by the Taiwan <span class="hlt">Earthquake</span> <span class="hlt">Model</span> (TEM). The BPT <span class="hlt">model</span> was adopted to describe the rupture recurrence 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 rate change based on the static Coulomb stress interaction between seismogenic sources. By considering above time-dependent factors, our new combined <span class="hlt">model</span> 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 recurrence 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 <span class="hlt">models</span>, to provide time-dependent <span class="hlt">earthquake</span> probability constraints. Our time-dependent <span class="hlt">model</span> considers more detailed information than any other published <span class="hlt">models</span>. 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/2011JGRB..116.5204B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRB..116.5204B"><span>Stochastic <span class="hlt">models</span> for <span class="hlt">earthquake</span> triggering of volcanic eruptions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bebbington, M. S.; Marzocchi, W.</p> <p>2011-05-01</p> <p>Many accounts, anecdotal and statistical, have noted a causal effect on volcanic eruptions from large, not too distant, <span class="hlt">earthquakes</span>. Physical mechanisms have been proposed that explain how small static stress changes, or larger transient dynamic stress changes, can have observable effects on a volcano. While only ˜0.4% of eruptions appear to be directly triggered within a few days of an <span class="hlt">earthquake</span>, these physical mechanisms also imply the possibility of delayed triggering. In the few regional studies conducted, data issues (selection bias and scarcity, inhomogeneity, and cleaning of data) have tended to obscure any clear signal. Using a perturbation technique, we first show that the Indonesian volcanic region possesses no statistically significant coupling for the region as a whole. We then augment a number of point process <span class="hlt">models</span> for eruption onsets by a time-, distance-, and <span class="hlt">earthquake</span> magnitude-dependent triggering term and apply this to the individual volcanoes. This method weighs both positive and negative (i.e., absence of eruptions following an <span class="hlt">earthquake</span>) evidence of triggering. Of 35 volcanoes with at least three eruptions in the study region, seven (Marapi, Talang, Krakatau, Slamet, Ebulobo, Lewotobi, and Ruang) show statistical evidence of triggering over varying temporal and spatial scales, but only after the internal state of the volcano is accounted for. This confirms that triggering is fundamentally a property of the internal magma plumbing of the volcano in question and that any <span class="hlt">earthquake</span> can potentially "advance the clock" toward a future eruption. This is further supported by the absence of any dependence on triggering of the eruption size.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/809873','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/809873"><span>Parity <span class="hlt">Non-Conservation</span> in Proton-Proton Elastic Scattering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>V.R. Brown; B.F. Gibson; J.A. Carlson; R. Schiavilla</p> <p>2002-06-01</p> <p>The parity <span class="hlt">non-conserving</span> longitudinal asymmetry in proton-proton (pp) elastic scattering is calculated in the lab-energy range 0-350 MeV using contemporary, realistic strong-interaction potentials combined with a weak-interaction potential comprised of rho- and omega-meson exchanges as exemplified by the DDH <span class="hlt">model</span>. Values for the rho- and omega-meson coupling constants, h{sup rho rho}{sub rho} and h{sup rho rho}{sub omega}, are determined from comparison with the measured asymmetries at 13.6 MeV, 45 MeV, and 221 MeV.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvE..93b2137T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvE..93b2137T"><span><span class="hlt">Nonconservative</span> dynamics of optically trapped high-aspect-ratio nanowires</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toe, Wen Jun; Ortega-Piwonka, Ignacio; Angstmann, Christopher N.; Gao, Qiang; Tan, Hark Hoe; Jagadish, Chennupati; Henry, Bruce I.; Reece, Peter J.</p> <p>2016-02-01</p> <p>We investigate the dynamics of high-aspect-ratio nanowires trapped axially in a single gradient force optical tweezers. A power spectrum analysis of the dynamics reveals a broad spectral resonance of the order of kHz with peak properties that are strongly dependent on the input trapping power. A dynamical <span class="hlt">model</span> incorporating linear restoring optical forces, a <span class="hlt">nonconservative</span> asymmetric coupling between translational and rotational degrees of freedom, viscous drag, and white noise provides an excellent fit to experimental observations. A persistent low-frequency cyclical motion around the equilibrium trapping position, with a frequency distinct from the spectral resonance, is observed from the time series data.</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('http://adsabs.harvard.edu/abs/2004PhRvL..92r1602A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004PhRvL..92r1602A"><span>Observation of Parity <span class="hlt">Nonconservation</span> in Møller Scattering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anthony, P. L.; Arnold, R. G.; Arroyo, C.; Baird, K.; Bega, K.; Biesiada, J.; Bosted, P. E.; Breuer, M.; Carr, R.; Cates, G. D.; Chen, J.-P.; Chudakov, E.; Cooke, M.; Decker, F. J.; Decowski, P.; Deur, A.; Emam, W.; Erickson, R.; Fieguth, T.; Field, C.; Gao, J.; Gustafsson, K.; Hicks, R. S.; Holmes, R.; Hughes, E. W.; Humensky, T. B.; Jones, G. M.; Kaufman, L. J.; Kolomensky, Yu. G.; Kumar, K. S.; Lhuillier, D.; Lombard-Nelsen, R.; Mastromarino, P.; Mayer, B.; McKeown, R. D.; Michaels, R.; Olson, M.; Paschke, K. D.; Peterson, G. A.; Pitthan, R.; Pope, K.; Relyea, D.; Rock, S. E.; Saxton, O.; Shapiro, G.; Singh, J.; Souder, P. A.; Szalata, Z. M.; Tobias, W. A.; Tonguc, B. T.; Turner, J.; Tweedie, B.; Vacheret, A.; Walz, D.; Weber, T.; Weisend, J.; Whittum, D.; Woods, M.; Younus, I.</p> <p>2004-05-01</p> <p>We report a measurement of the parity-violating asymmetry in fixed target electron-electron (Møller) scattering: APV=[-175±30(stat)±20(syst)]×10-9. This first direct observation of parity <span class="hlt">nonconservation</span> in Møller scattering leads to a measurement of the electron's weak charge at low energy QeW=-0.053±0.011. This is consistent with the standard <span class="hlt">model</span> expectation at the current level of precision: sin(2θW(MZ)MS¯=0.2293±0.0024(stat)±0.0016(syst)±0.0006(theory).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70017331','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70017331"><span>Desk-top <span class="hlt">model</span> buildings for dynamic <span class="hlt">earthquake</span> response demonstrations</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brady, A. Gerald</p> <p>1992-01-01</p> <p><span class="hlt">Models</span> of buildings that illustrate dynamic resonance behavior when excited by hand are designed and built. Two types of buildings are considered, one with columns stronger than floors, the other with columns weaker than floors. Combinations and variations of these two types are possible. Floor masses and column stiffnesses are chosen in order that the frequency of the second mode is approximately five cycles per second, so that first and second modes can be excited manually. The <span class="hlt">models</span> are expected to be resonated by hand by schoolchildren or persons unfamiliar with the dynamic resonant response of tall buildings, to gain an understanding of structural behavior during <span class="hlt">earthquakes</span>. Among other things, this experience will develop a level of confidence in the builder and experimenter should they be in a high-rise building during an <span class="hlt">earthquake</span>, sensing both these resonances and other violent shaking.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.S53B1098M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.S53B1098M"><span><span class="hlt">Earthquake</span> potential at Parkfield, CA inferred from geodetic data spanning two <span class="hlt">earthquake</span> cycles with assessment of <span class="hlt">model</span> resolution and uncertainty</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murray, J. R.; Langbein, J.</p> <p>2005-12-01</p> <p>Although some <span class="hlt">models</span> used in long-term <span class="hlt">earthquake</span> forecasting treat <span class="hlt">earthquake</span> occurrence as a time-independent process, it is generally accepted that an <span class="hlt">earthquake</span> relieves accumulated stress on a fault and that time is required to rebuild stress before another large event. This idea is embodied in the time-predictable <span class="hlt">model</span> for <span class="hlt">earthquake</span> recurrence, which is used in hazard forecasting. The related slip-predictable <span class="hlt">model</span> states that <span class="hlt">earthquake</span> size is proportional to the time since the last event and the fault stressing rate. Geodetic data offer a means of measuring strain accumulation and release in the Earth's crust throughout the <span class="hlt">earthquake</span> cycle. Inversion of these data can provide useful inputs, such as estimates of slip in <span class="hlt">earthquakes</span> or the long-term slip rate, to recurrence <span class="hlt">models</span>. However, the slip resolution of geodetic observations decreases with depth on the fault. If the results of geodetic <span class="hlt">modeling</span> are to be properly incorporated into hazard forecasts, it is critical to assess which features of the <span class="hlt">models</span> are robust by quantifying the <span class="hlt">model</span> resolution and the uncertainties of estimated parameters. With geodetic measurements for the three most recent <span class="hlt">earthquakes</span> (in 1934, 1966, and 2004), Parkfield, California is one of the few locales where geodetic data span multiple <span class="hlt">earthquake</span> cycles. Sparse observations exist for the 1934 - 1966 time period, and geodetic monitoring steadily increased during the 1966 - 2004 interseismic period. Through joint inversion of the variety of Parkfield geodetic measurements (triangulation, trilateration, two-color laser, and GPS) we obtain the most detailed image yet of the evolution of slip on the fault since the 1934 <span class="hlt">earthquake</span>. Obtaining the <span class="hlt">model</span> resolution and <span class="hlt">model</span> covariance matrices is straightforward for linear inversions. However, due to the inclusion of non-negativity constraints, the inversions of Parkfield data are nonlinear. We apply an alternative technique for calculating the <span class="hlt">model</span> resolution and use the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/386961','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/386961"><span>Single-particle parity-<span class="hlt">nonconserving</span> matrix elements in {sup 207}Pb</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Komives, A.; Knott, J.E.; Leuschner, M.; Szymanski, J.J.; Bowman, J.D.; Jamrisk, D.</p> <p>1993-10-01</p> <p>Measurements of the helicity dependence of neutron scattering off of heavy nuclei by the TRIPLE collaboration have yielded multiple parity-<span class="hlt">nonconserving</span> asymmetries. The asymmetries are predominantly positive, in contradiction to the zero average asymmetry predicted by the statistical <span class="hlt">model</span> of neutron- nucleus scattering. Theoretical calculations that explain the non-zero average asymmetry require single-particle parity- <span class="hlt">nonconserving</span> matrix elements 10-100 times larger than those predicted by meson exchange <span class="hlt">models</span>. We are determining the single-particle parity <span class="hlt">non-conserving</span> mixing in {sup 207}Pb by measuring the circular polarization of the 1.064 MeV {gamma} ray. The experiment uses a transmission polarimeter and a fast data acquisition system. Initial results are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.G31A1036L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.G31A1036L"><span>A unified source <span class="hlt">model</span> of the 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>Liu, G.; Wang, Q.; Qiao, X.</p> <p>2016-12-01</p> <p>On 25 April 2015, Gorkha <span class="hlt">earthquake</span> struck the central Nepal, for which diverse data sets including InSAR-mapped surface displacements and especially high-rate GPS-derived strong ground motions are available to depict its rupture process, providing an unprecedented opportunity to assess their contributions to the inversion of source parameters of a large megathrust <span class="hlt">earthquake</span>. We investigate space-time history of fault slip during the Gorkha <span class="hlt">earthquake</span> mainshock (Mw=7.8) and its largest aftershock (Mw=7.3) using separate and joint inversions of high-rate GPS, static GPS, InSAR data, teleseismic waves and strong-motion data to pursue a self-consistency and compatible rupture <span class="hlt">model</span>. First we constructed checkerboard tests to investigate the resolution for slip <span class="hlt">models</span> and the sensitivity for rupture velocity produced by individual datasets. Joints <span class="hlt">models</span> have best resolution and more stable to rupture velocity changing. High-rate GPS is more sensitive to rupture velocity than teleseismic P. After obtaining preferred rupture velocity and subfault rise time by using tradeoff line between cross correlation of observed and synthetic HRGPS versus rupture velocity and subfault rise time, we performed separate inversions of individual datasets. Separately inverted <span class="hlt">models</span> present different slip patterns due to intrinsic resolution of different dataset. Near-field datasets joint <span class="hlt">model</span> improves resolution of GPS <span class="hlt">models</span>, but no better than InSAR <span class="hlt">model</span>. Joint <span class="hlt">model</span> of all datasets, supplemented by the far-field, preserves common features of separate inversions, and identifies two slip patches in high slip area. We explored influence of many parameters affecting inversions and found slip pattern is relatively stable, but except for the choice of rupture velocity and weights of datasets. We exploit the trade-off curve of rupture velocity and waveform misfit residual to yield an appropriate <span class="hlt">model</span> rupture velocity. Our choice of weighting between datasets comes from evaluation of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Nonli..30.2805B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Nonli..30.2805B"><span>Singular limit analysis of a <span class="hlt">model</span> for <span class="hlt">earthquake</span> faulting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bossolini, Elena; Brøns, Morten; Uldall Kristiansen, Kristian</p> <p>2017-07-01</p> <p>In this paper we consider a one dimensional spring-block <span class="hlt">model</span> describing <span class="hlt">earthquake</span> faulting. By using geometric singular perturbation theory and the blow-up method, we provide a detailed description of the periodicity of the <span class="hlt">earthquake</span> episodes. In particular, we show that the limit cycles arise from a degenerate Hopf bifurcation, whose degeneracy is due to an underlying Hamiltonian structure that leads to large amplitude oscillations. We use a Poincaré compactification to study the system near infinity. At infinity, the critical manifold loses hyperbolicity with an exponential rate. We use an adaptation of the blow-up method to recover the hyperbolicity. This enables the identification of a new attracting manifold that organises the dynamics at infinity. This in turn leads to the formulation of a conjecture on the behaviour of the limit cycles as the time-scale separation increases. We illustrate our findings with numerics, and suggest an outline of the proof of the conjecture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.H43C1463G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.H43C1463G"><span><span class="hlt">Modeling</span> long-term hillslope denudation due to large <span class="hlt">earthquakes</span>: Example from the Wenchuan 2008 <span class="hlt">earthquake</span>, Longmen Shan, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gallen, S. F.; Clark, M. K.</p> <p>2013-12-01</p> <p>Most moderate to large <span class="hlt">earthquakes</span> in high-relief terrain trigger landslides. Much research has focused on identifying hazards associated with hillslopes that are potentially seismically unstable. Recently, there has been greater recognition in the role of seismically-induced landsliding in drainage basin-to-orogen scale denudation, particularly over geologic timescales. The 2008 Mw 7.9 Wenchuan <span class="hlt">earthquake</span> in the Longmen Shan Mountains in western Sichuan Province, China, provided unprecedented opportunity to collect geophysical and geomorphological data sets related to <span class="hlt">earthquake</span>-driven landsliding. Based on landslide inventories, some suggest that this single event resulted in the displacement of hillslope mass equal or greater than that of the cosesimic displacement. The magnitude and availability of data for the Wenchuan <span class="hlt">earthquake</span> make it an ideal testing ground for new mechanistic <span class="hlt">models</span> related to <span class="hlt">earthquake</span>-driven landsliding and landscape evolution. We develop and apply a mechanistic slope stability <span class="hlt">model</span> that allows for estimates of the volume hillslope mass removal during an <span class="hlt">earthquake</span> at the regional scale. In our <span class="hlt">model</span>, slope performance and landslide potential during seismic accelerations are determined using the Newmark sliding block <span class="hlt">model</span>. In Newmark analysis, surface displacement occurs when a critical or yield ground acceleration exceeds to the shear strength of the material. Site specific characteristics, such as local slope and rock-type, provide the basis to estimate static slope stability conditions and a given peak ground acceleration (PGA) scenario is used to <span class="hlt">model</span> potential slope failures. Predicted spatial distributions, statistical characteristics and net volume of landslide mass were generally similar to measured inventories of coseismic landsliding. To extend the coseismic mass-wasting <span class="hlt">model</span> to geological time-scales, we applied a simple stochastic <span class="hlt">model</span> of <span class="hlt">earthquake</span> nucleation and empirical PGA attenuation equations to simulate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S33C4538S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S33C4538S"><span><span class="hlt">Earthquake</span> Early Warning Beta Users: Java, <span class="hlt">Modeling</span>, and Mobile Apps</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Strauss, J. A.; Vinci, M.; Steele, W. P.; Allen, R. M.; Hellweg, M.</p> <p>2014-12-01</p> <p><span class="hlt">Earthquake</span> Early Warning (EEW) is a system that can provide a few to tens of seconds warning prior to ground shaking at a user's location. The goal and purpose of such a system is to reduce, or minimize, the damage, costs, and casualties resulting from an <span class="hlt">earthquake</span>. A demonstration <span class="hlt">earthquake</span> early warning system (ShakeAlert) is undergoing testing in the United States by the UC Berkeley Seismological Laboratory, Caltech, ETH Zurich, University of Washington, the USGS, and beta users in California and the Pacific Northwest. The beta users receive <span class="hlt">earthquake</span> information very rapidly in real-time and are providing feedback on their experiences of performance and potential uses within their organization. Beta user interactions allow the ShakeAlert team to discern: which alert delivery options are most effective, what changes would make the UserDisplay more useful in a pre-disaster situation, and most importantly, what actions users plan to take for various scenarios. Actions could include: personal safety approaches, such as drop cover, and hold on; automated processes and procedures, such as opening elevator or fire stations doors; or situational awareness. Users are beginning to determine which policy and technological changes may need to be enacted, and funding requirements to implement their automated controls. The use of <span class="hlt">models</span> and mobile apps are beginning to augment the basic Java desktop applet. <span class="hlt">Modeling</span> allows beta users to test their early warning responses against various scenarios without having to wait for a real event. Mobile apps are also changing the possible response landscape, providing other avenues for people to receive information. All of these combine to improve business continuity and resiliency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.4992O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.4992O"><span><span class="hlt">Modelling</span> <span class="hlt">earthquake</span> ruptures with dynamic off-fault damage</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Okubo, Kurama; Bhat, Harsha S.; Klinger, Yann; Rougier, Esteban</p> <p>2017-04-01</p> <p><span class="hlt">Earthquake</span> rupture <span class="hlt">modelling</span> has been developed for producing scenario <span class="hlt">earthquakes</span>. This includes understanding the source mechanisms and estimating far-field ground motion with given a priori constraints like fault geometry, constitutive law of the medium and friction law operating on the fault. It is necessary to consider all of the above complexities of a fault systems to conduct realistic <span class="hlt">earthquake</span> rupture <span class="hlt">modelling</span>. In addition to the complexity of the fault geometry in nature, coseismic off-fault damage, which is observed by a variety of geological and seismological methods, plays a considerable role on the resultant ground motion and its spectrum compared to a <span class="hlt">model</span> with simple planer fault surrounded by purely elastic media. Ideally all of these complexities should be considered in <span class="hlt">earthquake</span> <span class="hlt">modelling</span>. State of the art techniques developed so far, however, cannot treat all of them simultaneously due to a variety of computational restrictions. Therefore, we adopt the combined finite-discrete element method (FDEM), which can effectively deal with pre-existing complex fault geometry such as fault branches and kinks and can describe coseismic off-fault damage generated during the dynamic rupture. The advantage of FDEM is that it can handle a wide range of length scales, from metric to kilometric scale, corresponding to the off-fault damage and complex fault geometry respectively. We used the FDEM-based software tool called HOSSedu (Hybrid Optimization Software Suite - Educational Version) for the <span class="hlt">earthquake</span> rupture <span class="hlt">modelling</span>, which was developed by Los Alamos National Laboratory. We firstly conducted the cross-validation of this new methodology against other conventional numerical schemes such as the finite difference method (FDM), the spectral element method (SEM) and the boundary integral equation method (BIEM), to evaluate the accuracy with various element sizes and artificial viscous damping values. We demonstrate the capability of the FDEM tool for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.1509G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.1509G"><span>Italian Case Studies <span class="hlt">Modelling</span> Complex <span class="hlt">Earthquake</span> Sources In PSHA</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gee, Robin; Peruzza, Laura; Pagani, Marco</p> <p>2017-04-01</p> <p>This study presents two examples of <span class="hlt">modelling</span> complex seismic sources in Italy, done in the framework of regional probabilistic seismic hazard assessment (PSHA). The first case study is for an area centred around Collalto Stoccaggio, a natural gas storage facility in Northern Italy, located within a system of potentially seismogenic thrust faults in the Venetian Plain. The storage exploits a depleted natural gas reservoir located within an actively growing anticline, which is likely driven by the Montello Fault, the underlying blind thrust. This fault has been well identified by microseismic activity (M<2) detected by a local seismometric network installed in 2012 (http://rete-collalto.crs.inogs.it/). At this time, no correlation can be identified between the gas storage activity and local seismicity, so we proceed with a PSHA that considers only natural seismicity, where the rates of <span class="hlt">earthquakes</span> are assumed to be time-independent. The source <span class="hlt">model</span> consists of faults and distributed seismicity to consider <span class="hlt">earthquakes</span> that cannot be associated to specific structures. All potentially active faults within 50 km of the site are considered, and are <span class="hlt">modelled</span> as 3D listric surfaces, consistent with the proposed geometry of the Montello Fault. Slip rates are constrained using available geological, geophysical and seismological information. We explore the sensitivity of the hazard results to various parameters affected by epistemic uncertainty, such as ground motions prediction equations with different rupture-to-site distance metrics, fault geometry, and maximum magnitude. The second case is an innovative study, where we perform aftershock probabilistic seismic hazard assessment (APSHA) in Central Italy, following the Amatrice M6.1 <span class="hlt">earthquake</span> of August 24th, 2016 (298 casualties) and the subsequent <span class="hlt">earthquakes</span> of Oct 26th and 30th (M6.1 and M6.6 respectively, no deaths). The aftershock hazard is <span class="hlt">modelled</span> using a fault source with complex geometry, based on literature data</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S23A0287H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S23A0287H"><span>Comparison of Short-term and Long-term <span class="hlt">Earthquake</span> Forecast <span class="hlt">Models</span> for Southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Helmstetter, A.; Kagan, Y. Y.; Jackson, D. D.</p> <p>2004-12-01</p> <p>Many <span class="hlt">earthquakes</span> are triggered in part by preceding events. Aftershocks are the most obvious examples, but many large <span class="hlt">earthquakes</span> are preceded by smaller ones. The large fluctuations of seismicity rate due to <span class="hlt">earthquake</span> interactions thus provide a way to improve <span class="hlt">earthquake</span> forecasting significantly. We have developed a <span class="hlt">model</span> to estimate daily <span class="hlt">earthquake</span> probabilities in Southern California, using the Epidemic Type <span class="hlt">Earthquake</span> Sequence <span class="hlt">model</span> [Kagan and Knopoff, 1987; Ogata, 1988]. The forecasted seismicity rate is the sum of a constant external loading and of the aftershocks of all past <span class="hlt">earthquakes</span>. The background rate is estimated by smoothing past seismicity. Each <span class="hlt">earthquake</span> triggers aftershocks with a rate that increases exponentially with its magnitude and which decreases with time following Omori's law. We use an isotropic kernel to <span class="hlt">model</span> the spatial distribution of aftershocks for small (M≤5.5) mainshocks, and a smoothing of the location of early aftershocks for larger mainshocks. The <span class="hlt">model</span> also assumes that all <span class="hlt">earthquake</span> magnitudes follow the Gutenberg-Richter law with a unifom b-value. We use a maximum likelihood method to estimate the <span class="hlt">model</span> parameters and tests the short-term and long-term forecasts. A retrospective test using a daily update of the forecasts between 1985/1/1 and 2004/3/10 shows that the short-term <span class="hlt">model</span> decreases the uncertainty of an <span class="hlt">earthquake</span> occurrence by a factor of about 10.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMNH43C..08P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMNH43C..08P"><span><span class="hlt">Earthquake</span> Lights: Time-dependent Earth Surface - Ionosphere Coupling <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pasko, V. P.</p> <p>2012-12-01</p> <p>Co-seismic luminescence, commonly referred to as <span class="hlt">Earthquake</span> lights (EQLs), is an atmospheric luminous phenomenon occurring during strong <span class="hlt">earthquakes</span> and lasting from a fraction of a second to a few minutes [e.g., Derr, J. S., Bull. Seismol. Soc. Am., 63, 2177, 1973; St-Laurent, F., et al., Phys. Chem. Earth, 31, 305, 2006; Herauld and Lira, Nat. Hazards Earth Syst. Sci., 11, 1025, 2011]. Laboratory experiments of Freund, F. T., et al. [JGR, 105, 11001, 2000; JASTP, 71, 1824, 2009, and references therein] demonstrate that rocks subjected to stress force can generate electric currents. During <span class="hlt">earthquakes</span> these currents can deliver significant amounts of net positive charge to the ground-air interface leading to enhancements in the electric field and corona discharges around ground objects [Freund et al., 2009]. The eyewitness reports [Herauld and Lira, 2011] indicate similarities of the blue glow observed during EQLs to St. Elmo's fire observed during thunderstorms around wing tips of airplanes or around the tall masts of sailing ships [e.g., Wescott, E.M., et al., GRL, 23, 3687, 1996]. Recent work indicates that the vertical currents induced in the stressed rock can map to ionospheric altitudes and create 10s of % variations in the total electron content in the Earth's ionosphere above the <span class="hlt">earthquake</span> active region [Kuo, C. L., et al., JGR, 116, A10317, 2011]. The magnitudes of the vertical currents estimated by Kuo et al. [2011] based on work by Freund et al. [2009] range from 0.01 to 10 μA/m2. In this talk we report results from a new time-dependent <span class="hlt">model</span> allowing to calculate currents induced in the ambient atmosphere and corona currents under application of vertical stressed rock currents with arbitrary time variation. We will report test results documenting the <span class="hlt">model</span> performance under conditions: (1) relaxation toward the classic global electric circuit conditions in fair weather regions when ionosphere is maintained at 300 kV with respect to the ground; (2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhRvL.103j8101W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhRvL.103j8101W"><span>Direct Measurement of the <span class="hlt">Nonconservative</span> Force Field Generated by Optical Tweezers</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wu, Pinyu; Huang, Rongxin; Tischer, Christian; Jonas, Alexandr; Florin, Ernst-Ludwig</p> <p>2009-09-01</p> <p>The force field of optical tweezers is commonly assumed to be conservative, neglecting the complex action of the scattering force. Using a novel method that extracts local forces from trajectories of an optically trapped particle, we measure the three-dimensional force field experienced by a Rayleigh particle with 10 nm spatial resolution and femtonewton precision in force. We find that the force field is <span class="hlt">nonconservative</span> with the <span class="hlt">nonconservative</span> component increasing radially away from the optical axis, in agreement with the Gaussian beam <span class="hlt">model</span> of the optical trap.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNG21A1811T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNG21A1811T"><span>Spatial and Temporal Clustering in a Simple <span class="hlt">Earthquake</span> Asperity <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tiampo, K. F.; Kazemian, J.; Dominguez, R.; Klein, W.</p> <p>2016-12-01</p> <p>Natural <span class="hlt">earthquake</span> fault systems are highly heterogeneous in space, the result of inhomogeneities that are a function of the variety of materials of different strengths. However, despite their inhomogeneous nature, real faults are often <span class="hlt">modeled</span> as spatially homogeneous systems. Here we present a simple <span class="hlt">earthquake</span> fault <span class="hlt">model</span> based on the Olami-Feder-Christensen (OFC) and Rundle-Jackson-Brown (RJB) cellular automata <span class="hlt">models</span> with long-range interactions that incorporates asperities, or stronger sites, into the lattice (Rundle and Jackson, 1977; Olami et al., 1992). These asperity cells are significantly stronger than the surrounding lattice sites but eventually rupture when the applied stress reaches their higher threshold stress. The introduction of these spatial heterogeneities results in spatial and temporal clustering in the <span class="hlt">model</span> similar to that seen in natural fault systems. We observe sequences of activity that begin with a gradually accelerating number of larger events, or foreshocks, prior to a large event, followed by a tail of decreasing activity, or aftershocks. These recurrent large events occur at regular intervals and the characteristic time between events and their magnitude are a function of the stress dissipation parameter. The relative length of the foreshock to aftershock sequence depends on the amount of stress dissipation in the system. This work provides further evidence that the spatial and temporal patterns observed in natural seismicity are strongly influenced by the underlying physical properties and are not solely the result of a simple cascade mechanism. We find that the scaling depends not only on the amount of damage, but also on the spatial distribution of that damage (Dominguez et al., 2011; Kazemian et al., 2014). Here we compare the <span class="hlt">modeled</span> sequences to those of natural <span class="hlt">earthquake</span> sequences from California and around the world in order to investigate the interplay between cascade dynamics and spatial structure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10181241','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10181241"><span>Limits on CP <span class="hlt">nonconserving</span> interactions from electric dipole moments</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Haxton, W.C.</p> <p>1994-09-01</p> <p>I discuss bounds on CP-<span class="hlt">nonconserving</span> (CPNC) and parity-<span class="hlt">nonconserving</span> (PNC) hadronic interactions that result from measurements of atomic electric dipole moments. In most <span class="hlt">models</span> of hadronic CPNC, the nuclear edm arises primarily from the polarization of the ground state by the CPNC PNC NN interaction, rather than from the edms of valence nucleons. When the atom is placed in an external field, the nucleus is fully shielded apart from nuclear finite size effects and relativistic corrections arising from hyperfine interactions, so that careful atomic calculations must be performed to deduce the residual sensitivity to the nuclear edm. I describe these shielding effects qualitatively, and present results from more detailed calculations. Atomic limits, when translated into effective bounds on the neutron edm, have now reached sensitivities that are comparable to direct neutron edm limits. I also discuss limits that can be extracted on CPNC parity-conserving (PC) hadronic interactions. Such interactions can generate atomic edms when combined with weak radiative corrections.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5033007','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5033007"><span>Mechanical <span class="hlt">model</span> of precursory source processes for some large <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dmorvska, R.; Li, V.C.</p> <p>1982-04-01</p> <p>A mechanical <span class="hlt">model</span> is presented of precursory source processes for some large <span class="hlt">earthquakes</span> along plate boundaries. It is assumed that the pre-seismic period consists of the upward progression of a zone of slip from lower portions of the lithosphere towards the Earth's surface. The slip front is blocked by local asperities of different size and strength; these asperities may be zones of real alteration of inherent strength, or instead may be zones which are currently stronger due to a local slowdown of a basically rate-dependent frictional response. Such blocking by a single, large asperity, or array of asperities, produces quiescence over a segment of plate boundary, until gradual increase of the stress concentration forces the slip zone through the blocked region at one end of the gap, thus nucleating a seismic rupture that propogates upwards and towards the other end. This <span class="hlt">model</span> is proposed to explain certain distinctive seismicity patterns that have been observed before large <span class="hlt">earthquakes</span>, notably quiescence over the gap zone followed by clustering at its end prior to the main event. A discussion of mechanical factors influencing the process is presented and some introductory <span class="hlt">modelling</span>, performed with the use of a generalized Elsasser <span class="hlt">model</span> for lithospheric plates and the ''line spring'' <span class="hlt">model</span> for part-through flaws (slip zones) at plate boundaries, is outlined briefly.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4940731','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4940731"><span>Optimized volume <span class="hlt">models</span> of <span class="hlt">earthquake</span>-triggered landslides</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Xu, Chong; Xu, Xiwei; Shen, Lingling; Yao, Qi; Tan, Xibin; Kang, Wenjun; Ma, Siyuan; Wu, Xiyan; Cai, Juntao; Gao, Mingxing; Li, Kang</p> <p>2016-01-01</p> <p>In this study, we proposed three optimized <span class="hlt">models</span> for calculating the total volume of landslides triggered by the 2008 Wenchuan, China Mw 7.9 <span class="hlt">earthquake</span>. First, we calculated the volume of each deposit of 1,415 landslides triggered by the quake based on pre- and post-quake DEMs in 20 m resolution. The samples were used to fit the conventional landslide “volume-area” power law relationship and the 3 optimized <span class="hlt">models</span> we proposed, respectively. Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 <span class="hlt">models</span>. Results show that original data-based nonlinear least square combining with an optimized <span class="hlt">model</span> considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance. This <span class="hlt">model</span> was subsequently applied to the database of landslides triggered by the quake except for two largest ones with known volumes. It indicates that the total volume of the 196,007 landslides is about 1.2 × 1010 m3 in deposit materials and 1 × 1010 m3 in source areas, respectively. The result from the relationship of quake magnitude and entire landslide volume related to individual <span class="hlt">earthquake</span> is much less than that from this study, which reminds us the necessity to update the power-law relationship. PMID:27404212</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27404212','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27404212"><span>Optimized volume <span class="hlt">models</span> of <span class="hlt">earthquake</span>-triggered landslides.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Xu, Chong; Xu, Xiwei; Shen, Lingling; Yao, Qi; Tan, Xibin; Kang, Wenjun; Ma, Siyuan; Wu, Xiyan; Cai, Juntao; Gao, Mingxing; Li, Kang</p> <p>2016-07-12</p> <p>In this study, we proposed three optimized <span class="hlt">models</span> for calculating the total volume of landslides triggered by the 2008 Wenchuan, China Mw 7.9 <span class="hlt">earthquake</span>. First, we calculated the volume of each deposit of 1,415 landslides triggered by the quake based on pre- and post-quake DEMs in 20 m resolution. The samples were used to fit the conventional landslide "volume-area" power law relationship and the 3 optimized <span class="hlt">models</span> we proposed, respectively. Two data fitting methods, i.e. log-transformed-based linear and original data-based nonlinear least square, were employed to the 4 <span class="hlt">models</span>. Results show that original data-based nonlinear least square combining with an optimized <span class="hlt">model</span> considering length, width, height, lithology, slope, peak ground acceleration, and slope aspect shows the best performance. This <span class="hlt">model</span> was subsequently applied to the database of landslides triggered by the quake except for two largest ones with known volumes. It indicates that the total volume of the 196,007 landslides is about 1.2 × 10(10) m(3) in deposit materials and 1 × 10(10) m(3) in source areas, respectively. The result from the relationship of quake magnitude and entire landslide volume related to individual <span class="hlt">earthquake</span> is much less than that from this study, which reminds us the necessity to update the power-law relationship.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21544621','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21544621"><span>Calculation of parity <span class="hlt">nonconservation</span> in neutral ytterbium</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dzuba, V. A.; Flambaum, V. V.</p> <p>2011-04-15</p> <p>We use configuration interaction and many-body perturbation theory techniques to calculate spin-independent and spin-dependent parts of the parity-<span class="hlt">nonconserving</span> amplitudes of the transitions between the 6s{sup 2} {sup 1}S{sub 0} ground state and the 6s5d {sup 3}D{sub 1} excited state of {sup 171}Yb and {sup 173}Yb. The results are presented in a form convenient for extracting spin-dependent interaction constants (such as anapole moment) from the measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JESS..126....4S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JESS..126....4S"><span>3-D GRACE gravity <span class="hlt">model</span> for the 2011 Japan <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>Sastry, Rambhatla G.; Sonker, Mahendra K.</p> <p>2017-02-01</p> <p>The GRACE mission has contributed to the seismic characterization of major <span class="hlt">earthquakes</span> in offshore regions of the world. Here, we isolate satellite gravity signal (μGal range) for the Japan <span class="hlt">Earthquake</span> of 2011 using a difference method. Contrary to the existing gravity <span class="hlt">models</span>, we propose a unit vertical pyramid based five-layer 3-D thrust fault <span class="hlt">model</span>, which extends to the hypocenter and honors the ocean water layer and sea floor upheaval also. Our <span class="hlt">model</span> partly uses existing seismological information (hypocenter depth of 32 km, rupture length of 300 km and vertical slip of 4 m), provides a snapshot of episodic subduction of the Pacific Plate below the Atlantic Plate and its gravity response closely matches the observed gravity (RMS error of 3.4012×10-13μGal), fully accounting for co-seismic mass redistribution including sea surface deformation. Our inferred rupture length, rupture velocity, average seismic moment magnitude and momentum, respectively, are 300 km, 4.49 km/s, 1.152×1021-1.8816×1021 N m and 2.319×106 GNs, which fairly agree with the literature. Further, our <span class="hlt">model</span> inferred momentum at the sea floor corresponds to an area pulse that led to Tsunami generation.</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/2016FrES...10..740Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016FrES...10..740Y"><span>Newmark displacement <span class="hlt">model</span> for landslides induced by the 2013 Ms 7.0 Lushan <span class="hlt">earthquake</span>, China</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yuan, Renmao; Deng, Qinghai; Cunningham, Dickson; Han, Zhujun; Zhang, Dongli; Zhang, Bingliang</p> <p>2016-12-01</p> <p>Predicting approximate <span class="hlt">earthquake</span>-induced landslide displacements is helpful for assessing <span class="hlt">earthquake</span> hazards and designing slopes to withstand future <span class="hlt">earthquake</span> shaking. In this work, the basic methodology outlined by Jibson (1993) is applied to derive the Newmark displacement of landslides based on strong ground-motion recordings during the 2013 Lushan Ms 7.0 <span class="hlt">earthquake</span>. By analyzing the relationships between Arias intensity, Newmark displacement, and critical acceleration of the Lushan <span class="hlt">earthquake</span>, formulas of the Jibson93 and its modified <span class="hlt">models</span> are shown to be applicable to the Lushan <span class="hlt">earthquake</span> dataset. Different empirical equations with new fitting coefficients for estimating Newmark displacement are then developed for comparative analysis. The results indicate that a modified <span class="hlt">model</span> has a better goodness of fit and a smaller estimation error for the Jibson93 formula. It indicates that the modified <span class="hlt">model</span> may be more reasonable for the dataset of the Lushan <span class="hlt">earthquake</span>. The analysis of results also suggests that a global equation is not ideally suited to directly estimate the Newmark displacements of landslides induced by one specific <span class="hlt">earthquake</span>. Rather it is empirically better to perform a new multivariate regression analysis to derive new coefficients for the global equation using the dataset of the specific <span class="hlt">earthquake</span>. The results presented in this paper can be applied to a future co-seismic landslide hazard assessment to inform reconstruction efforts in the area affected by the 2013 Lushan Ms 7.0 <span class="hlt">earthquake</span>, and for future disaster prevention and mitigation.</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 <span class="hlt">Models</span></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 <span class="hlt">models</span> 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 <span class="hlt">models</span> 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 <span class="hlt">models</span> that, in contrast, highlight the role of stress loading concentration, rather than frictional segmentation. These <span class="hlt">models</span> produce "super-cycles" comprising recurrent 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('https://www.ncbi.nlm.nih.gov/pubmed/17769162','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17769162"><span><span class="hlt">Earthquake</span> prediction: <span class="hlt">modeling</span> the anomalous vp/vs source region.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Griggs, D T; Jackson, D D; Knopoff, L; Shreve, R L</p> <p>1975-02-14</p> <p>Soviet observations of anomalously low values of the ratio of the compressional wave velocity to the shear wave velocity (V(p)/ V(s)) in a restricted volume around the locus of a future <span class="hlt">earthquake</span> are duplicated by <span class="hlt">models</span> based on the dilatancy hypothesis. In nature the cracks that cause the dilation may be oriented, leading to anisotropic seismic wave propagation in the anomalous region. The <span class="hlt">models</span> show that vertical cracks are most effective in producing the observed effects, but that a slightly higher density of randomly oriented cracks will yield similar effects. The premonitory observations at Blue Mountain Lake, New York, are also duplicated by the <span class="hlt">models</span>. These <span class="hlt">models</span> demonstrate that V(p)/V(s) measured at the surface is not that of the anomalous zone, but is related to it by a transfer function, involving the shape and velocity gradient of the zone boundary.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.C21A0723S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.C21A0723S"><span>Numerical <span class="hlt">modeling</span> of glacial <span class="hlt">earthquakes</span> induced by iceberg capsize</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sergeant, A.; Yastrebov, V.; Castelnau, O.; Mangeney, A.; Stutzmann, E.; Montagner, J. P.; Burton, J. C.</p> <p>2015-12-01</p> <p>Glacial <span class="hlt">earthquakes</span> is a class of seismic events of magnitude up to 5, occurring primarily in Greenland, in the margins of large marine-terminated glaciers with near-grounded termini. They are caused by calving of cubic-kilometer scale unstable icebergs which penetrate the full-glacier thickness and, driven by the buoyancy forces, capsize against the calving front. These phenomena produce seismic energy including surface waves with dominant energy between 10-150 s of period whose seismogenic source is compatible with the contact force exerted on the terminus by the iceberg while it capsizes. A reverse motion and posterior rebound of the terminus have also been measured and associated with the fluctuation of this contact force. Using a finite element <span class="hlt">model</span> of iceberg and glacier terminus coupled with simplified fluid-structure interaction <span class="hlt">model</span>, we simulate calving and capsize of icebergs. Contact and frictional forces are measured on the terminus and compared with laboratory experiments. We also study the influence of various factors, such as iceberg geometry, calving style and terminus interface. Being extended to field environments, the simulation results are compared with forces obtained by seismic waveform inversion of registered glacial <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3887376','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3887376"><span>Short-Term Forecasting of Taiwanese <span class="hlt">Earthquakes</span> Using a Universal <span class="hlt">Model</span> of Fusion-Fission Processes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cheong, Siew Ann; Tan, Teck Liang; Chen, Chien-Chih; Chang, Wu-Lung; Liu, Zheng; Chew, Lock Yue; Sloot, Peter M. A.; Johnson, Neil F.</p> <p>2014-01-01</p> <p>Predicting how large an <span class="hlt">earthquake</span> can be, where and when it will strike remains an elusive goal in spite of the ever-increasing volume of data collected by earth scientists. In this paper, we introduce a universal <span class="hlt">model</span> of fusion-fission processes that can be used to predict <span class="hlt">earthquakes</span> starting from catalog data. We show how the equilibrium dynamics of this <span class="hlt">model</span> very naturally explains the Gutenberg-Richter law. Using the high-resolution <span class="hlt">earthquake</span> catalog of Taiwan between Jan 1994 and Feb 2009, we illustrate how out-of-equilibrium spatio-temporal signatures in the time interval between <span class="hlt">earthquakes</span> and the integrated energy released by <span class="hlt">earthquakes</span> can be used to reliably determine the times, magnitudes, and locations of large <span class="hlt">earthquakes</span>, as well as the maximum numbers of large aftershocks that would follow. PMID:24406467</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24406467','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24406467"><span>Short-term forecasting of Taiwanese <span class="hlt">earthquakes</span> using a universal <span class="hlt">model</span> of fusion-fission processes.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Cheong, Siew Ann; Tan, Teck Liang; Chen, Chien-Chih; Chang, Wu-Lung; Liu, Zheng; Chew, Lock Yue; Sloot, Peter M A; Johnson, Neil F</p> <p>2014-01-10</p> <p>Predicting how large an <span class="hlt">earthquake</span> can be, where and when it will strike remains an elusive goal in spite of the ever-increasing volume of data collected by earth scientists. In this paper, we introduce a universal <span class="hlt">model</span> of fusion-fission processes that can be used to predict <span class="hlt">earthquakes</span> starting from catalog data. We show how the equilibrium dynamics of this <span class="hlt">model</span> very naturally explains the Gutenberg-Richter law. Using the high-resolution <span class="hlt">earthquake</span> catalog of Taiwan between Jan 1994 and Feb 2009, we illustrate how out-of-equilibrium spatio-temporal signatures in the time interval between <span class="hlt">earthquakes</span> and the integrated energy released by <span class="hlt">earthquakes</span> can be used to reliably determine the times, magnitudes, and locations of large <span class="hlt">earthquakes</span>, as well as the maximum numbers of large aftershocks that would follow.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/286037','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/286037"><span>Universality in Sandpiles, Interface Depinning, and <span class="hlt">Earthquake</span> <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Paczuski, M.; Boettcher, S. |</p> <p>1996-07-01</p> <p>Recent numerical results for a <span class="hlt">model</span> describing dispersive transport in ricepiles are explained by mapping the <span class="hlt">model</span> to the depinning transition of an elastic interface that is dragged at one end through a random medium. The average velocity of transport vanishes with system size {ital L} as {l_angle}{ital v}{r_angle}{approximately}{ital L}{sup 2{minus}{ital D}}{approximately}{ital L}{sup {minus}0.23}, and the avalanche size distribution exponent {tau}=2{minus}1/{ital D}{approx_equal}1.55, where {ital D}{approx_equal}2.23 from interface depinning. We conjecture that the purely deterministic Burridge-Knopoff {open_quote}{open_quote}train{close_quote}{close_quote} <span class="hlt">model</span> for <span class="hlt">earthquakes</span> is in the same universality class. {copyright} {ital 1996 The American Physical Society.}</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5482298','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5482298"><span>Time-predictable recurrence <span class="hlt">model</span> for large <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Shimazaki, K.; Nakata, T.</p> <p>1980-04-01</p> <p>We present historical and geomorphological evidence of a regularity in <span class="hlt">earthquake</span> recurrence at three different sites of plate convergence around the Japan arcs. The regularity shows that the larger an <span class="hlt">earthquake</span> is, the longer is the following quiet period. In other words, the time interval between two successive large <span class="hlt">earthquakes</span> is approximately proportional to the amount of coseismic displacement of the preceding <span class="hlt">earthquake</span> and not of the following <span class="hlt">earthquake</span>. The regularity enables us, in principle, to predict the approximate occurrence time of <span class="hlt">earthquakes</span>. The data set includes 1) a historical document describing repeated measurements of water depth at Murotsu near the focal region of Nankaido <span class="hlt">earthquakes</span>, 2) precise levelling and /sup 14/C dating of Holocene uplifted terraces in the southern boso peninsula facing the Sagami trough, and 3) similar geomorphological data on exposed Holocene coral reefs in Kikai Island along the Ryukyu arc.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014CEJG....6..403C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014CEJG....6..403C"><span>Prediction of <span class="hlt">earthquake</span> hazard by hidden Markov <span class="hlt">model</span> (around Bilecik, NW Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Can, Ceren Eda; Ergun, Gul; Gokceoglu, Candan</p> <p>2014-09-01</p> <p><span class="hlt">Earthquakes</span> are one of the most important natural hazards to be evaluated carefully in engineering projects, due to the severely damaging effects on human-life and human-made structures. The hazard of an <span class="hlt">earthquake</span> is defined by several approaches and consequently <span class="hlt">earthquake</span> parameters such as peak ground acceleration occurring on the focused area can be determined. In an <span class="hlt">earthquake</span> prone area, the identification of the seismicity patterns is an important task to assess the seismic activities and evaluate the risk of damage and loss along with an <span class="hlt">earthquake</span> occurrence. As a powerful and flexible framework to characterize the temporal seismicity changes and reveal unexpected patterns, Poisson hidden Markov <span class="hlt">model</span> provides a better understanding of the nature of <span class="hlt">earthquakes</span>. In this paper, Poisson hidden Markov <span class="hlt">model</span> is used to predict the <span class="hlt">earthquake</span> hazard in Bilecik (NW Turkey) as a result of its important geographic location. Bilecik is in close proximity to the North Anatolian Fault Zone and situated between Ankara and Istanbul, the two biggest cites of Turkey. Consequently, there are major highways, railroads and many engineering structures are being constructed in this area. The annual frequencies of <span class="hlt">earthquakes</span> occurred within a radius of 100 km area centered on Bilecik, from January 1900 to December 2012, with magnitudes ( M) at least 4.0 are <span class="hlt">modeled</span> by using Poisson-HMM. The hazards for the next 35 years from 2013 to 2047 around the area are obtained from the <span class="hlt">model</span> by forecasting the annual frequencies of M ≥ 4 <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014OGeo....6..403C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014OGeo....6..403C"><span>Prediction of <span class="hlt">earthquake</span> hazard by hidden Markov <span class="hlt">model</span> (around Bilecik, NW Turkey)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Can, Ceren; Ergun, Gul; Gokceoglu, Candan</p> <p>2014-09-01</p> <p><span class="hlt">Earthquakes</span> are one of the most important natural hazards to be evaluated carefully in engineering projects, due to the severely damaging effects on human-life and human-made structures. The hazard of an <span class="hlt">earthquake</span> is defined by several approaches and consequently <span class="hlt">earthquake</span> parameters such as peak ground acceleration occurring on the focused area can be determined. In an <span class="hlt">earthquake</span> prone area, the identification of the seismicity patterns is an important task to assess the seismic activities and evaluate the risk of damage and loss along with an <span class="hlt">earthquake</span> occurrence. As a powerful and flexible framework to characterize the temporal seismicity changes and reveal unexpected patterns, Poisson hidden Markov <span class="hlt">model</span> provides a better understanding of the nature of <span class="hlt">earthquakes</span>. In this paper, Poisson hidden Markov <span class="hlt">model</span> is used to predict the <span class="hlt">earthquake</span> hazard in Bilecik (NW Turkey) as a result of its important geographic location. Bilecik is in close proximity to the North Anatolian Fault Zone and situated between Ankara and Istanbul, the two biggest cites of Turkey. Consequently, there are major highways, railroads and many engineering structures are being constructed in this area. The annual frequencies of <span class="hlt">earthquakes</span> occurred within a radius of 100 km area centered on Bilecik, from January 1900 to December 2012, with magnitudes (M) at least 4.0 are <span class="hlt">modeled</span> by using Poisson-HMM. The hazards for the next 35 years from 2013 to 2047 around the area are obtained from the <span class="hlt">model</span> by forecasting the annual frequencies of M ≥ 4 <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH13D1954S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH13D1954S"><span>The Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> and Disaster Risk Reduction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Smolka, A. J.</p> <p>2015-12-01</p> <p>Advanced, reliable and transparent tools and data to assess <span class="hlt">earthquake</span> risk are inaccessible to most, especially in less developed regions of the world while few, if any, globally accepted standards currently allow a meaningful comparison of risk between places. The Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> (GEM) is a collaborative effort that aims to provide <span class="hlt">models</span>, datasets and state-of-the-art tools for transparent assessment of <span class="hlt">earthquake</span> hazard and risk. As part of this goal, GEM and its global network of collaborators have developed the OpenQuake engine (an open-source software for hazard and risk calculations), the OpenQuake platform (a web-based portal making GEM's resources and datasets freely available to all potential users), and a suite of tools to support <span class="hlt">modelers</span> and other experts in the development of hazard, exposure and vulnerability <span class="hlt">models</span>. These resources are being used extensively across the world in hazard and risk assessment, from individual practitioners to local and national institutions, and in regional projects to inform disaster risk reduction. Practical examples for how GEM is bridging the gap between science and disaster risk reduction are: - Several countries including Switzerland, Turkey, Italy, Ecuador, Papua-New Guinea and Taiwan (with more to follow) are computing national seismic hazard using the OpenQuake-engine. In some cases these results are used for the definition of actions in building codes. - Technical support, tools and data for the development of hazard, exposure, vulnerability and risk <span class="hlt">models</span> for regional projects in South America and Sub-Saharan Africa. - Going beyond physical risk, GEM's scorecard approach evaluates local resilience by bringing together neighborhood/community leaders and the risk reduction community as a basis for designing risk reduction programs at various levels of geography. Actual case studies are Lalitpur in the Kathmandu Valley in Nepal and Quito/Ecuador. In agreement with GEM's collaborative approach, all</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S52F0178C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S52F0178C"><span>A Hidden Markov Approach to <span class="hlt">Modeling</span> Interevent <span class="hlt">Earthquake</span> Times</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chambers, D.; Ebel, J. E.; Kafka, A. L.; Baglivo, J.</p> <p>2003-12-01</p> <p>A hidden Markov process, in which the interevent time distribution is a mixture of exponential distributions with different rates, is explored as a <span class="hlt">model</span> for seismicity that does not follow a Poisson process. In a general hidden Markov <span class="hlt">model</span>, one assumes that a system can be in any of a finite number k of states and there is a random variable of interest whose distribution depends on the state in which the system resides. The system moves probabilistically among the states according to a Markov chain; that is, given the history of visited states up to the present, the conditional probability that the next state is a specified one depends only on the present state. Thus the transition probabilities are specified by a k by k stochastic matrix. Furthermore, it is assumed that the actual states are unobserved (hidden) and that only the values of the random variable are seen. From these values, one wishes to estimate the sequence of states, the transition probability matrix, and any parameters used in the state-specific distributions. The hidden Markov process was applied to a data set of 110 interevent times for <span class="hlt">earthquakes</span> in New England from 1975 to 2000. Using the Baum-Welch method (Baum et al., Ann. Math. Statist. 41, 164-171), we estimate the transition probabilities, find the most likely sequence of states, and estimate the k means of the exponential distributions. Using k=2 states, we found the data were fit well by a mixture of two exponential distributions, with means of approximately 5 days and 95 days. The steady state <span class="hlt">model</span> indicates that after approximately one fourth of the <span class="hlt">earthquakes</span>, the waiting time until the next event had the first exponential distribution and three fourths of the time it had the second. Three and four state <span class="hlt">models</span> were also fit to the data; the data were inconsistent with a three state <span class="hlt">model</span> but were well fit by a four state <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70031809','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70031809"><span>Ground-motion <span class="hlt">modeling</span> of the 1906 San Francisco <span class="hlt">earthquake</span>, part I: Validation using the 1989 Loma Prieta <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>Aagaard, B.T.; Brocher, T.M.; Dolenc, D.; Dreger, D.; Graves, R.W.; Harmsen, S.; Hartzell, S.; Larsen, S.; Zoback, M.L.</p> <p>2008-01-01</p> <p>We compute ground motions for the Beroza (1991) and Wald et al. (1991) source <span class="hlt">models</span> of the 1989 magnitude 6.9 Loma Prieta <span class="hlt">earthquake</span> using four different wave-propagation codes and recently developed 3D geologic and seismic velocity <span class="hlt">models</span>. In preparation for <span class="hlt">modeling</span> the 1906 San Francisco <span class="hlt">earthquake</span>, we use this well-recorded <span class="hlt">earthquake</span> to characterize how well our ground-motion simulations reproduce the observed shaking intensities and amplitude and durations of recorded motions throughout the San Francisco Bay Area. All of the simulations generate ground motions consistent with the large-scale spatial variations in shaking associated with rupture directivity and the geologic structure. We attribute the small variations among the synthetics to the minimum shear-wave speed permitted in the simulations and how they accommodate topography. Our long-period simulations, on average, under predict shaking intensities by about one-half modified Mercalli intensity (MMI) units (25%-35% in peak velocity), while our broadband simulations, on average, under predict the shaking intensities by one-fourth MMI units (16% in peak velocity). Discrepancies with observations arise due to errors in the source <span class="hlt">models</span> and geologic structure. The consistency in the synthetic waveforms across the wave-propagation codes for a given source <span class="hlt">model</span> suggests the uncertainty in the source parameters tends to exceed the uncertainty in the seismic velocity structure. In agreement with earlier studies, we find that a source <span class="hlt">model</span> with slip more evenly distributed northwest and southeast of the hypocenter would be preferable to both the Beroza and Wald source <span class="hlt">models</span>. Although the new 3D seismic velocity <span class="hlt">model</span> improves upon previous velocity <span class="hlt">models</span>, we identify two areas needing improvement. Nevertheless, we find that the seismic velocity <span class="hlt">model</span> and the wave-propagation codes are suitable for <span class="hlt">modeling</span> the 1906 <span class="hlt">earthquake</span> and scenario events in the San Francisco Bay Area.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22596691','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22596691"><span>Phase response curves for <span class="hlt">models</span> of <span class="hlt">earthquake</span> fault dynamics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Franović, Igor; Kostić, Srdjan; Perc, Matjaž; Klinshov, Vladimir; Nekorkin, Vladimir; Kurths, Jürgen</p> <p>2016-06-15</p> <p>We systematically study effects of external perturbations on <span class="hlt">models</span> describing <span class="hlt">earthquake</span> fault dynamics. The latter are based on the framework of the Burridge-Knopoff spring-block system, including the cases of a simple mono-block fault, as well as the paradigmatic complex faults made up of two identical or distinct blocks. The blocks exhibit relaxation oscillations, which are representative for the stick-slip behavior typical for <span class="hlt">earthquake</span> dynamics. Our analysis is carried out by determining the phase response curves of first and second order. For a mono-block fault, we consider the impact of a single and two successive pulse perturbations, further demonstrating how the profile of phase response curves depends on the fault parameters. For a homogeneous two-block fault, our focus is on the scenario where each of the blocks is influenced by a single pulse, whereas for heterogeneous faults, we analyze how the response of the system depends on whether the stimulus is applied to the block having a shorter or a longer oscillation period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27368770','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27368770"><span>Phase response curves for <span class="hlt">models</span> of <span class="hlt">earthquake</span> fault dynamics.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Franović, Igor; Kostić, Srdjan; Perc, Matjaž; Klinshov, Vladimir; Nekorkin, Vladimir; Kurths, Jürgen</p> <p>2016-06-01</p> <p>We systematically study effects of external perturbations on <span class="hlt">models</span> describing <span class="hlt">earthquake</span> fault dynamics. The latter are based on the framework of the Burridge-Knopoff spring-block system, including the cases of a simple mono-block fault, as well as the paradigmatic complex faults made up of two identical or distinct blocks. The blocks exhibit relaxation oscillations, which are representative for the stick-slip behavior typical for <span class="hlt">earthquake</span> dynamics. Our analysis is carried out by determining the phase response curves of first and second order. For a mono-block fault, we consider the impact of a single and two successive pulse perturbations, further demonstrating how the profile of phase response curves depends on the fault parameters. For a homogeneous two-block fault, our focus is on the scenario where each of the blocks is influenced by a single pulse, whereas for heterogeneous faults, we analyze how the response of the system depends on whether the stimulus is applied to the block having a shorter or a longer oscillation period.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA......450E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA......450E"><span><span class="hlt">Modelling</span> the <span class="hlt">earthquake</span> intensities: A case study on the faults of the Marmara Region, NW Turkey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Erturac, M. K.; Tuysuz, O.</p> <p>2003-04-01</p> <p>North Anatolian Fault Zone is the biggest neo-tectonic structure of the Asia Minor. 17 August 1999 M=7.4 Izmit <span class="hlt">earthquake</span> was the seventh in a sequence of westward migrating <span class="hlt">earthquakes</span> along this fault. The <span class="hlt">earthquake</span> sequence which began with the 1939 Erzincan <span class="hlt">earthquake</span>, caused rupture of 1000 km section of the fault with maximum displacement of 7.5 meters. The time interval between these <span class="hlt">earthquakes</span> varied from 3 months to 32 years. Stress triggering has been invoked to explain the 60-year sequence of <span class="hlt">earthquakes</span> rupturing toward the west, in which every event promoted the next. The Izmit <span class="hlt">earthquake</span> increased the probability of future <span class="hlt">earthquake</span> in the Sea of Marmara region. GPS, historical and instrumental <span class="hlt">earthquake</span> data, and estimated stress triggering indicate a remarkable probability (62 % ±15) of a strong shaking in the Marmara Sea region during the next 30 years which threats the city of Istanbul. Active faults in the Sea of Marmara is mapped and published by different companies. By using these recent data, local geology, site conditions and attenuation relationships, it is possible to estimate the degree of shaking for a future <span class="hlt">earthquake</span>. In this study we used geographical information systems as a tool for such a <span class="hlt">modeling</span>. In the light of fault length, previous <span class="hlt">earthquake</span> data and GPS measurements we attributed possible magnitudes for each segment. Then we used different attenuation relationships to obtain the distribution of possible peak ground accelerations. These data is correlated with the recorded attenuations. After choosing appropriate formula, the peak ground accelerations converted to intensity values. The <span class="hlt">model</span> is also applied to data obtained during the 1999 Izmit (Mw 7.3) and Duzce (Mw 7.2) <span class="hlt">earthquakes</span> to test the consistency of the results. In this presentation <span class="hlt">models</span> for different fault segments will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH54B..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH54B..01R"><span>Nowcasting <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>Rundle, J. B.; Donnellan, A.; Grant Ludwig, L.; Turcotte, D. L.; Luginbuhl, M.; Gail, G.</p> <p>2016-12-01</p> <p>Nowcasting is a term originating from economics and finance. It refers to the process of determining the uncertain state of the economy or markets at the current time by indirect means. We apply this idea to seismically active regions, where the goal is to determine the current state of the fault system, and its current level of progress through the <span class="hlt">earthquake</span> cycle. In our implementation of this idea, we use the global catalog of <span class="hlt">earthquakes</span>, using "small" <span class="hlt">earthquakes</span> to determine the level of hazard from "large" <span class="hlt">earthquakes</span> in the region. Our method does not involve any <span class="hlt">model</span> other than the idea of an <span class="hlt">earthquake</span> cycle. Rather, we define a specific region and a specific large <span class="hlt">earthquake</span> magnitude of interest, ensuring that we have enough data to span at least 20 or more large <span class="hlt">earthquake</span> cycles in the region. We then compute the <span class="hlt">earthquake</span> potential score (EPS) which is defined as the cumulative probability distribution P(n<n(t)) for the current count n(t) for the small <span class="hlt">earthquakes</span> in the region. From the count of small <span class="hlt">earthquakes</span> since the last large <span class="hlt">earthquake</span>, we determine the value of EPS = P(n<n(t)). EPS is therefore the current level of hazard, and assigns a number between 0% and 100% to every region so defined, thus providing a unique measure. Physically, the EPS corresponds to an estimate of the level of progress through the <span class="hlt">earthquake</span> cycle in the defined region at the current time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016E%26SS....3..480R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016E%26SS....3..480R"><span>Nowcasting <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>Rundle, J. B.; Turcotte, D. L.; Donnellan, A.; Grant Ludwig, L.; Luginbuhl, M.; Gong, G.</p> <p>2016-11-01</p> <p>Nowcasting is a term originating from economics and finance. It refers to the process of determining the uncertain state of the economy or markets at the current time by indirect means. We apply this idea to seismically active regions, where the goal is to determine the current state of the fault system and its current level of progress through the <span class="hlt">earthquake</span> cycle. In our implementation of this idea, we use the global catalog of <span class="hlt">earthquakes</span>, using "small" <span class="hlt">earthquakes</span> to determine the level of hazard from "large" <span class="hlt">earthquakes</span> in the region. Our method does not involve any <span class="hlt">model</span> other than the idea of an <span class="hlt">earthquake</span> cycle. Rather, we define a specific region and a specific large <span class="hlt">earthquake</span> magnitude of interest, ensuring that we have enough data to span at least 20 or more large <span class="hlt">earthquake</span> cycles in the region. We then compute the <span class="hlt">earthquake</span> potential score (EPS) which is defined as the cumulative probability distribution P(n < n(t)) for the current count n(t) for the small <span class="hlt">earthquakes</span> in the region. From the count of small <span class="hlt">earthquakes</span> since the last large <span class="hlt">earthquake</span>, we determine the value of EPS = P(n < n(t)). EPS is therefore the current level of hazard and assigns a number between 0% and 100% to every region so defined, thus providing a unique measure. Physically, the EPS corresponds to an estimate of the level of progress through the <span class="hlt">earthquake</span> cycle in the defined region at the current time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10193934','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10193934"><span>Parity <span class="hlt">nonconservation</span> in radioactive atoms: An experimental perspective</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vieira, D.</p> <p>1994-11-01</p> <p>The measurement of parity <span class="hlt">nonconservation</span> (PNC) in atoms constitutes an important test of electroweak interactions in nuclei. Great progress has been made over the last 20 years in performing these measurements with ever increasing accuracies. To date the experimental accuracies have reached a level of 1 to 2%. In all cases, except for cesium, the theoretical atomic structure uncertainties now limit the comparison of these measurements to the predictions of the standard <span class="hlt">model</span>. New measurements involving the ratio of Stark interference transition rates for a series of Cs or Fr radioisotopes are foreseen as a way of eliminating these atomic structure uncertainties. The use of magneto-optical traps to collect and concentrate the much smaller number of radioactive atoms that are produced is considered to be one of the key steps in realizing these measurements. Plans for how these measurements will be done and progress made to date are outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAESc.114..299C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAESc.114..299C"><span>Statistical analysis of <span class="hlt">earthquakes</span> after the 1999 MW 7.7 Chi-Chi, Taiwan, <span class="hlt">earthquake</span> based on a modified Reasenberg-Jones <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Yuh-Ing; Huang, Chi-Shen; Liu, Jann-Yenq</p> <p>2015-12-01</p> <p>We investigated the temporal-spatial hazard of the <span class="hlt">earthquakes</span> after the 1999 September 21 MW = 7.7 Chi-Chi shock in a continental region of Taiwan. The Reasenberg-Jones (RJ) <span class="hlt">model</span> (Reasenberg and Jones, 1989, 1994) that combines the frequency-magnitude distribution (Gutenberg and Richter, 1944) and time-decaying occurrence rate (Utsu et al., 1995) is conventionally employed for assessing the <span class="hlt">earthquake</span> hazard after a large shock. However, it is found that the b values in the frequency-magnitude distribution of the <span class="hlt">earthquakes</span> in the study region dramatically decreased from background values after the Chi-Chi shock, and then gradually increased up. The observation of a time-dependent frequency-magnitude distribution motivated us to propose a modified RJ <span class="hlt">model</span> (MRJ) to assess the <span class="hlt">earthquake</span> hazard. To see how the <span class="hlt">models</span> perform on assessing short-term <span class="hlt">earthquake</span> hazard, the RJ and MRJ <span class="hlt">models</span> were separately used to sequentially forecast <span class="hlt">earthquakes</span> in the study region. To depict the potential rupture area for future <span class="hlt">earthquakes</span>, we further constructed relative hazard (RH) maps based on the two <span class="hlt">models</span>. The Receiver Operating Characteristics (ROC) curves (Swets, 1988) finally demonstrated that the RH map based on the MRJ <span class="hlt">model</span> was, in general, superior to the one based on the original RJ <span class="hlt">model</span> for exploring the spatial hazard of <span class="hlt">earthquakes</span> in a short time after the Chi-Chi shock.</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://pubs.er.usgs.gov/publication/70048493','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70048493"><span><span class="hlt">Modeling</span> <span class="hlt">earthquake</span> rate changes in Oklahoma and Arkansas: possible signatures of induced 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>Llenos, Andrea L.; Michael, Andrew J.</p> <p>2013-01-01</p> <p>The rate of ML≥3 <span class="hlt">earthquakes</span> 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 <span class="hlt">earthquakes</span> in Oklahoma, which had a low background seismicity rate before 2009, as well as rate changes in a catalog of ML≥2.2 <span class="hlt">earthquakes</span> in central Arkansas, which had a history of <span class="hlt">earthquake</span> swarms prior to the start of injection in 2009. In both cases, stochastic epidemic‐type aftershock sequence <span class="hlt">models</span> and statistical tests demonstrate that the <span class="hlt">earthquake</span> rate change is statistically significant, and both the background rate of independent <span class="hlt">earthquakes</span> 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 <span class="hlt">earthquake</span> rate changes. In Arkansas we also compare <span class="hlt">earthquake</span> and injection well locations, finding that <span class="hlt">earthquakes</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S23B..04M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S23B..04M"><span>Some thoughts on the feasibility of the 'characteristic <span class="hlt">earthquake</span>' <span class="hlt">model</span>. (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Marzocchi, W.</p> <p>2010-12-01</p> <p>The conceptual <span class="hlt">model</span> of 'characteristic <span class="hlt">earthquake</span>' was introduced by Schwartz et al. (1981). In the original form, a characteristic <span class="hlt">earthquake</span> was defined only in terms of the <span class="hlt">earthquake</span> size on a specified fault; specifically, "faults tend to generate essentially same size <span class="hlt">earthquakes</span> having a relatively narrow range of magnitudes near the maximum". Later, this concept has been stretched by Schwartz and Coppersmith (1984), incorporating the "recurrence interval" hypothesis that was already suggested in the early seventies (Wallace, 1970). Notably, the concept of recurrence interval already implicitly includes the notion of <span class="hlt">earthquakes</span> with equal size; in fact, the temporal recurrence is based on the assumption that the amount of slip of past <span class="hlt">earthquake</span> is constant through time and, when divided by a steady fault slip rate, will lead to a nearly constant recurrence interval between these same size events. Since the eighties, the characteristic <span class="hlt">earthquake</span> concept has been used in different ways: as reported in the original form, i.e., <span class="hlt">earthquakes</span> on faults tend to produce <span class="hlt">earthquakes</span> of similar size, or in the more rich form, including time recurrence. An important generalization brought to the definition of the seismic gap hypothesis applied to restricted regions of the world. Remarkably, despite the simplicity and the reasonableness of the assumptions that stand behind the characteristic <span class="hlt">earthquake</span> <span class="hlt">model</span>, it has never fully accepted by many seismologists. Here, we bring to the attention some physical considerations and empirical observations that led (and lead) to skepticism in accepting this conceptual <span class="hlt">model</span>. Particular attention is also devoted to some important semantic issues that may have created part of the contention (surprisingly, there are still different views of what a 'fault' is). We discuss both the time and size regularities of the characteristic <span class="hlt">earthquake</span>; the final goal is to provide a critical overview of what may be really considered</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/992345','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/992345"><span><span class="hlt">Earthquake</span> Response <span class="hlt">Modeling</span> for a Parked and Operating Megawatt-Scale Wind Turbine</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Prowell, I.; Elgamal, A.; Romanowitz, H.; Duggan, J. E.; Jonkman, J.</p> <p>2010-10-01</p> <p>Demand parameters for turbines, such as tower moment demand, are primarily driven by wind excitation and dynamics associated with operation. For that purpose, computational simulation platforms have been developed, such as FAST, maintained by the National Renewable Energy Laboratory (NREL). For seismically active regions, building codes also require the consideration of <span class="hlt">earthquake</span> loading. Historically, it has been common to use simple building code approaches to estimate the structural demand from <span class="hlt">earthquake</span> shaking, as an independent loading scenario. Currently, International Electrotechnical Commission (IEC) design requirements include the consideration of <span class="hlt">earthquake</span> shaking while the turbine is operating. Numerical and analytical tools used to consider <span class="hlt">earthquake</span> loads for buildings and other static civil structures are not well suited for <span class="hlt">modeling</span> simultaneous wind and <span class="hlt">earthquake</span> excitation in conjunction with operational dynamics. Through the addition of seismic loading capabilities to FAST, it is possible to simulate <span class="hlt">earthquake</span> shaking in the time domain, which allows consideration of non-linear effects such as structural nonlinearities, aerodynamic hysteresis, control system influence, and transients. This paper presents a FAST <span class="hlt">model</span> of a modern 900-kW wind turbine, which is calibrated based on field vibration measurements. With this calibrated <span class="hlt">model</span>, both coupled and uncoupled simulations are conducted looking at the structural demand for the turbine tower. Response is compared under the conditions of normal operation and potential emergency shutdown due the <span class="hlt">earthquake</span> induced vibrations. The results highlight the availability of a numerical tool for conducting such studies, and provide insights into the combined wind-<span class="hlt">earthquake</span> loading mechanism.</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> Rate <span class="hlt">Model</span> 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 rates 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 <span class="hlt">model</span>. 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.osti.gov/scitech/biblio/20895193','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20895193"><span>Information Theoric Framework for the <span class="hlt">Earthquake</span> Recurrence <span class="hlt">Models</span> : Methodica Firma Per Terra Non-Firma</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Esmer, Oezcan</p> <p>2006-11-29</p> <p>This paper first evaluates the <span class="hlt">earthquake</span> prediction method (1999 ) used by US Geological Survey as the lead example and reviews also the recent <span class="hlt">models</span>. Secondly, points out the ongoing debate on the predictability of <span class="hlt">earthquake</span> recurrences and lists the main claims of both sides. The traditional methods and the 'frequentist' approach used in determining the <span class="hlt">earthquake</span> probabilities cannot end the complaints that the <span class="hlt">earthquakes</span> are unpredictable. It is argued that the prevailing 'crisis' in seismic research corresponds to the Pre-Maxent Age of the current situation. The period of Kuhnian 'Crisis' should give rise to a new paradigm based on the Information-Theoric framework including the inverse problem, Maxent and Bayesian methods. Paper aims to show that the information- theoric methods shall provide the required 'Methodica Firma' for the <span class="hlt">earthquake</span> prediction <span class="hlt">models</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.T13C4659W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.T13C4659W"><span>Finite-Source <span class="hlt">Modeling</span> for Parkfield and Anza <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>Wooddell, K. E.; Taira, T.; Dreger, D. S.</p> <p>2014-12-01</p> <p>Repeating <span class="hlt">earthquakes</span> occur in the vicinity of creeping sections along the Parkfield section of the San Andreas fault (Nadeau et al., 1995) and the Anza section of the San Jacinto fault (Taira, 2013). Uilizing an empirical Green's function (eGF) approach for both the Parkfield and Anza events, we are able to conduct a comparative study of the resulting slip distributions and source parameters to examine differences in the scaling of fault dimension, average slip, and peak-slip with magnitude. Following the approach of Dreger et al. (2007), moment rate functions (MRFs) are obtained at each station for both Parkfield and Anza <span class="hlt">earthquakes</span> using a spectral domain deconvolution approach where the complex spectrum of the eGF is divided out of the complex spectrum of the target event. Spatial distributions of fault slip are derived by inverting the MRFs, and the coseismic stress change is computed following the method of Ripperger and Mai (2004). Initial results are based on the analysis of several Parkfield target events ranging in magnitude from Mw1.8 to 6.0 (Dreger et al., 2011) and a Mw4.7 Anza event. Parkfield peak slips are consistent with the Nadeau and Johnson (1998) tectonic loading <span class="hlt">model</span>, while average slips tend to scale self-similarly. Results for the Anza event show very high peak and average slips, in exceedance of 50 cm and 10 cm respectively. Directivity for this event is in the northwest direction, and preliminary sensitivity analyses suggest that the rupture velocity is near the shear wave velocity and the rise time is short (~0.03 sec). Multiple eGFs for the Anza event have been evaluated and the results appear robust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....9573A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....9573A"><span>Acceleration <span class="hlt">modeling</span> of moderate to large <span class="hlt">earthquakes</span> based on realistic fault <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arvidsson, R.; Toral, J.</p> <p>2003-04-01</p> <p>Strong motion is affected by distance to the <span class="hlt">earthquake</span>, local crustal structure, focal mechanism, azimuth to the source. However, the faulting process is also of importance such as development of rupture, i.e., directivity, slip distribution on the fault, extent of fault, rupture velocity. We have <span class="hlt">modelled</span> these parameters for <span class="hlt">earthquakes</span> that occurred in three tectonic zones close to the Panama Canal. We included in the <span class="hlt">modeling</span> directivity, distributed slip, discrete faulting, fault depth and expected focal mechanism. The distributed slip is based on previous fault <span class="hlt">models</span> that we produced from the region of other <span class="hlt">earthquakes</span>. Such previous examples show that maximum intensities in some cases coincides with areas of high slip on the fault. Our acceleration <span class="hlt">modeling</span> also gives similar values to the few observations that have been made for moderate to small <span class="hlt">earthquakes</span> in the range M=5-6.2. The <span class="hlt">modeling</span> indicates that events located in the Caribbean might cause strong motion in the lower frequency spectra where high frequency Rayleigh waves dominates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011IzPSE..47..847Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011IzPSE..47..847Y"><span>One-dimensional velocity <span class="hlt">model</span> of the Middle Kura Depresion from local <span class="hlt">earthquakes</span> data of Azerbaijan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yetirmishli, G. C.; Kazimova, S. E.; Kazimov, I. E.</p> <p>2011-09-01</p> <p>We present the method for determining the velocity <span class="hlt">model</span> of the Earth's crust and the parameters of <span class="hlt">earthquakes</span> in the Middle Kura Depression from the data of network telemetry in Azerbaijan. Application of this method allowed us to recalculate the main parameters of the hypocenters of the <span class="hlt">earthquake</span>, to compute the corrections to the arrival times of P and S waves at the observation station, and to significantly improve the accuracy in determining the coordinates of the <span class="hlt">earthquakes</span>. The <span class="hlt">model</span> was constructed using the VELEST program, which calculates one-dimensional minimal velocity <span class="hlt">models</span> from the travel times of seismic waves.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/946928','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/946928"><span>Ground motion <span class="hlt">modeling</span> of the 1906 San Francisco <span class="hlt">earthquake</span> II: Ground motion estimates for the 1906 <span class="hlt">earthquake</span> and scenario events</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Aagaard, B; Brocher, T; Dreger, D; Frankel, A; Graves, R; Harmsen, S; Hartzell, S; Larsen, S; McCandless, K; Nilsson, S; Petersson, N A; Rodgers, A; Sjogreen, B; Tkalcic, H; Zoback, M L</p> <p>2007-02-09</p> <p>We estimate the ground motions produced by the 1906 San Francisco <span class="hlt">earthquake</span> making use of the recently developed Song et al. (2008) source <span class="hlt">model</span> that combines the available geodetic and seismic observations and recently constructed 3D geologic and seismic velocity <span class="hlt">models</span>. Our estimates of the ground motions for the 1906 <span class="hlt">earthquake</span> are consistent across five ground-motion <span class="hlt">modeling</span> groups employing different wave propagation codes and simulation domains. The simulations successfully reproduce the main features of the Boatwright and Bundock (2005) ShakeMap, but tend to over predict the intensity of shaking by 0.1-0.5 modified Mercalli intensity (MMI) units. Velocity waveforms at sites throughout the San Francisco Bay Area exhibit characteristics consistent with rupture directivity, local geologic conditions (e.g., sedimentary basins), and the large size of the event (e.g., durations of strong shaking lasting tens of seconds). We also compute ground motions for seven hypothetical scenarios rupturing the same extent of the northern San Andreas fault, considering three additional hypocenters and an additional, random distribution of slip. Rupture directivity exerts the strongest influence on the variations in shaking, although sedimentary basins do consistently contribute to the response in some locations, such as Santa Rosa, Livermore, and San Jose. These scenarios suggest that future large <span class="hlt">earthquakes</span> on the northern San Andreas fault may subject the current San Francisco Bay urban area to stronger shaking than a repeat of the 1906 <span class="hlt">earthquake</span>. Ruptures propagating southward towards San Francisco appear to expose more of the urban area to a given intensity level than do ruptures propagating northward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70025926','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70025926"><span>An empirical <span class="hlt">model</span> for <span class="hlt">earthquake</span> probabilities in the San Francisco Bay region, California, 2002-2031</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.; Hanks, T.C.; Bakun, W.H.</p> <p>2003-01-01</p> <p>The moment magnitude M 7.8 <span class="hlt">earthquake</span> in 1906 profoundly changed the rate of seismic activity over much of northern California. The low rate of seismic activity in the San Francisco Bay region (SFBR) since 1906, relative to that of the preceding 55 yr, is often explained as a stress-shadow effect of the 1906 <span class="hlt">earthquake</span>. However, existing elastic and visco-elastic <span class="hlt">models</span> of stress change fail to fully account for the duration of the lowered rate of <span class="hlt">earthquake</span> activity. We use variations in the rate of <span class="hlt">earthquakes</span> as a basis for a simple empirical <span class="hlt">model</span> for estimating the probability of M ≥6.7 <span class="hlt">earthquakes</span> in the SFBR. The <span class="hlt">model</span> preserves the relative magnitude distribution of sources predicted by the Working Group on California <span class="hlt">Earthquake</span> Probabilities' (WGCEP, 1999; WGCEP, 2002) <span class="hlt">model</span> of characterized ruptures on SFBR faults and is consistent with the occurrence of the four M ≥6.7 <span class="hlt">earthquakes</span> in the region since 1838. When the empirical <span class="hlt">model</span> is extrapolated 30 yr forward from 2002, it gives a probability of 0.42 for one or more M ≥6.7 in the SFBR. This result is lower than the probability of 0.5 estimated by WGCEP (1988), lower than the 30-yr Poisson probability of 0.60 obtained by WGCEP (1999) and WGCEP (2002), and lower than the 30-yr time-dependent probabilities of 0.67, 0.70, and 0.63 obtained by WGCEP (1990), WGCEP (1999), and WGCEP (2002), respectively, for the occurrence of one or more large <span class="hlt">earthquakes</span>. This lower probability is consistent with the lack of adequate accounting for the 1906 stress-shadow in these earlier reports. The empirical <span class="hlt">model</span> represents one possible approach toward accounting for the stress-shadow effect of the 1906 <span class="hlt">earthquake</span>. However, the discrepancy between our result and those obtained with other <span class="hlt">modeling</span> methods underscores the fact that the physics controlling the timing of <span class="hlt">earthquakes</span> is not well understood. Hence, we advise against using the empirical <span class="hlt">model</span> alone (or any other single probability <span class="hlt">model</span>) for estimating the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S31G..06D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S31G..06D"><span>Finite-Source <span class="hlt">Modeling</span> of the South Napa <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>Dreger, D. S.; Huang, M. H.; Wooddell, K. E.; Taira, T.; Luna, B.</p> <p>2014-12-01</p> <p>On August 24 2014 an Mw 6.0 <span class="hlt">earthquake</span> struck south-southwest of the city of Napa, California. As part of the Berkeley Seismological Laboratory (BSL) Alarm Response a seismic moment tensor solution and preliminary finite-source <span class="hlt">model</span> were estimated. The preliminary finite-source <span class="hlt">model</span> used high quality three-component strong motion recordings, instrument corrected and integrated to displacement, from 8 stations of the BSL BK network for stations located between 30 to 200 km. The BSL focal mechanism (strike=155, dip=82, rake=-172), and a constant rise time and rupture velocity were assumed. The GIL7 plane-layered velocity <span class="hlt">model</span> was used to compute Green's functions using a frequency wave-number integration approach. The preliminary <span class="hlt">model</span> from these stations indicates the rupture was unilateral to the NNW, and up dip with a average slip of 42 cm and peak slip of 102 cm. The total scalar moment was found to be 1.15*1025 dyne cm giving a Mw 6.0.The strong directivity from the rupture likely leads to the observed elevated local strong ground motions and the extensive damage to buildings in Napa and surrounding residential areas. In this study we will reevaluate the seismic moment tensor of the mainshock and larger aftershocks, and incorporate local strong motion waveforms, GPS, and InSAR deformation data to better constrain the finite-source <span class="hlt">model</span>. While the hypocenter and focal parameters used in the preliminary <span class="hlt">model</span> are consistent with the mapped surface trace of the west Napa fault, the mapped surface slip lies approximately 2 km to the west. Furthermore there is a pronounced change in strike of the mapped surface offsets at the northern end. We will investigate the location of the fault <span class="hlt">model</span> and the fit to the joint data set as well as examine the possibility of multi-segmented fault <span class="hlt">models</span> to account for these apparently inconsistent observations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22259754','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22259754"><span><span class="hlt">Nonconservative</span> current-induced forces: A physical interpretation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Todorov, Tchavdar N; Dundas, Daniel; Paxton, Anthony T; Horsfield, Andrew P</p> <p>2011-01-01</p> <p>We give a physical interpretation of the recently demonstrated <span class="hlt">nonconservative</span> nature of interatomic forces in current-carrying nanostructures. We start from the analytical expression for the curl of these forces, and evaluate it for a point defect in a current-carrying system. We obtain a general definition of the capacity of electrical current flow to exert a <span class="hlt">nonconservative</span> force, and thus do net work around closed paths, by a formal noninvasive test procedure. Second, we show that the gain in atomic kinetic energy over time, generated by <span class="hlt">nonconservative</span> current-induced forces, is equivalent to the uncompensated stimulated emission of directional phonons. This connection with electron-phonon interactions quantifies explicitly the intuitive notion that <span class="hlt">nonconservative</span> forces work by angular momentum transfer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002PApGe.159.2261D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002PApGe.159.2261D"><span>Combined GPS and InSAR <span class="hlt">Models</span> of Postseismic Deformation from the Northridge <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>Donnellan, A.; Parker, J. W.; Peltzer, G.</p> <p></p> <p><span class="hlt">Models</span> of combined Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data collected in the region of the Northridge <span class="hlt">earthquake</span> indicate that significant afterslip on the main fault occurred following the <span class="hlt">earthquake</span>. Additional shallow deformation occurred to the west of the main rupture plane. Both data sets are consistent with logarithmic time-dependent behavior following the <span class="hlt">earthquake</span> indicative of afterslip rather than postseismic relaxation. Aftershocks account for only about 10% of the postseismic motion. The two data sets are complimentary in determining the postseismic processes. Fault afterslip and shallow deformation dominate the deformation field in the two years following the <span class="hlt">earthquake</span>. Lower crustal deformation may play an important role later in the <span class="hlt">earthquake</span> cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S11A2769M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S11A2769M"><span>Integrated Seismicity <span class="hlt">Model</span> to Detect Pairs of Possible Interdependent <span class="hlt">Earthquakes</span> and Its Application to Aftershocks of the 2011 Tohoku-Oki <span class="hlt">Earthquake</span> and Sequence of the 2014 Kermadec and Rat Islands <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>Miyazawa, M.; Tamura, R.</p> <p>2015-12-01</p> <p>We introduce an integrated seismicity <span class="hlt">model</span> to stochastically evaluate the time intervals of consecutive <span class="hlt">earthquakes</span> at global scales, making it possible to detect a pair of <span class="hlt">earthquakes</span> that are remotely located and possibly related to each other. The <span class="hlt">model</span> includes seismicity in non-overlapping areas and comprehensively explains the seismicity on the basis of point process <span class="hlt">models</span>, which include the stationary Poisson <span class="hlt">model</span>, the aftershock decay <span class="hlt">model</span> following Omori-Utsu's law, and/or the epidemic-type aftershock sequence (ETAS) <span class="hlt">model</span>. By use of this <span class="hlt">model</span>, we examine the possibility of remote triggering of the 2011 M6.4 eastern Shizuoka <span class="hlt">earthquake</span> in the vicinity of Mt. Fuji that occurred 4 days after the Mw9.0 Tohoku-Oki <span class="hlt">earthquake</span> and 4 minutes after the M6.2 off-Fukushima <span class="hlt">earthquake</span> that located about 400 km away, and that of the 2014 Mw7.9 Rat Islands <span class="hlt">earthquake</span> that occurred within one hour after the Mw6.7 Kermadec <span class="hlt">earthquake</span> that located about 9,000 km away and followed two large (Mw6.9, 6.5) <span class="hlt">earthquakes</span> in the region. Both target <span class="hlt">earthquakes</span> occurred during the passage of surface waves propagating from the previous large events. We estimated probability that the time interval is shorter than that between consecutive events and obtained dynamic stress changes on the faults. The results indicate that the M6.4 eastern Shizuoka event may be rather triggered by the static stress changes from the Tohoku-Oki <span class="hlt">earthquake</span> and that the Mw7.9 Rat Islands event may have been remotely triggered by the Kermadec events possibly via cyclic fatigue.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911966S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911966S"><span>Three dimensional <span class="hlt">modelling</span> of <span class="hlt">earthquake</span> rupture cycles on frictional faults</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Simpson, Guy; May, Dave</p> <p>2017-04-01</p> <p>We are developing an efficient MPI-parallel numerical method to simulate <span class="hlt">earthquake</span> sequences on preexisting faults embedding within a three dimensional viscoelastic half-space. We solve the velocity form of the elasto(visco)dynamic equations using a continuous Galerkin Finite Element Method on an unstructured pentahedral mesh, which thus permits local spatial refinement in the vicinity of the fault. Friction sliding is coupled to the viscoelastic solid via rate- and state-dependent friction laws using the split-node technique. Our coupled formulation employs a picard-type non-linear solver with a fully implicit, first order accurate time integrator that utilises an adaptive time step that efficiently evolves the system through multiple seismic cycles. The implementation leverages advanced parallel solvers, preconditioners and linear algebra from the Portable Extensible Toolkit for Scientific Computing (PETSc) library. The <span class="hlt">model</span> can treat heterogeneous frictional properties and stress states on the fault and surrounding solid as well as non-planar fault geometries. Preliminary tests show that the <span class="hlt">model</span> successfully reproduces dynamic rupture on a vertical strike-slip fault in a half-space governed by rate-state friction with the ageing law.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S43B2776A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S43B2776A"><span>Validating a Dynamic <span class="hlt">Earthquake</span> <span class="hlt">Model</span> to Produce Realistic Ground Motion</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andrews, D. J.; Ma, S.</p> <p>2015-12-01</p> <p>A dynamic <span class="hlt">earthquake</span> <span class="hlt">model</span> is validated by finding good agreement with an empirical ground motion prediction equation. The <span class="hlt">model</span> replaces detailed deterministic processes on the fault with a stochastic emergent law. Initial stress on a fault plane is heterogeneous with a power-law spectrum that is self-similar. Rupture stops naturally. Rupture extent and moment are determined primarily by the specified lowest Fourier mode of initial stress. Higher modes are random with a self-similar spectrum that is tied to the amplitude of the lowest mode. Ten random realizations are calculated with a velocity structure for a hard rock site. The calculated mean response spectrum for M7 at a distance of 10 km agrees the with the GMPE of Boore et al (2013) within 0.25 of one standard deviation at periods from 0.3 seconds to 10 seconds. The agreement could be improved by using a more refined relation of the spatial stress spectrum to the amplitude of the lowest mode. The standard deviation of the calculated ground motion is somewhat smaller than the GMPE, but it depends on other rupture parameters and needs more investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815360S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815360S"><span>Numerical <span class="hlt">modelling</span> of iceberg calving force responsible for glacial <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>Sergeant, Amandine; Yastrebov, Vladislav; Castelnau, Olivier; Mangeney, Anne; Stutzmann, Eleonore; Montagner, Jean-Paul</p> <p>2016-04-01</p> <p>Glacial <span class="hlt">earthquakes</span> is a class of seismic events of magnitude up to 5, occurring primarily in Greenland, in the margins of large marine-terminated glaciers with near-grounded termini. They are caused by calving of cubic-kilometer scale unstable icebergs which penetrate the full-glacier thickness and, driven by the buoyancy forces, capsize against the calving front. These phenomena produce seismic energy including surface waves with dominant energy between 10-150 s of period whose seismogenic source is compatible with the contact force exerted on the terminus by the iceberg while it capsizes. A reverse motion and posterior rebound of the terminus have also been measured and associated with the fluctuation of this contact force. Using a finite element <span class="hlt">model</span> of iceberg and glacier terminus coupled with simplified fluid-structure interaction <span class="hlt">model</span>, we simulate calving and capsize of icebergs. Contact and frictional forces are measured on the terminus and compared with laboratory experiments. We also study the influence of geometric factors on the force history, amplitude and duration at the laboratory and field scales. We show first insights into the force and the generated seismic waves exploring different scenarios for iceberg capsizing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.T13B4643B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.T13B4643B"><span>Depths of Intraplate Indian Ocean <span class="hlt">Earthquakes</span> from Waveform <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baca, A. J.; Polet, J.</p> <p>2014-12-01</p> <p>The Indian Ocean is a region of complex tectonics and anomalous seismicity. The ocean floor in this region exhibits many bathymetric features, most notably the multiple inactive fracture zones within the Wharton Basin and the Ninetyeast Ridge. The 11 April 2012 MW 8.7 and 8.2 strike-slip events that took place in this area are unique because their rupture appears to have extended to a depth where brittle failure, and thus seismic activity, was considered to be impossible. We analyze multiple intraplate <span class="hlt">earthquakes</span> that have occurred throughout the Indian Ocean to better constrain their focal depths in order to enhance our understanding of how deep intraplate events are occurring and more importantly determine if the ruptures are originating within a ductile regime. Selected events are located within the Indian Ocean away from major plate boundaries. A majority are within the deforming Indo-Australian tectonic plate. Events primarily display thrust mechanisms with some strike-slip or a combination of the two. All events are between MW5.5-6.5. Event selections were handled this way in order to facilitate the analysis of teleseismic waveforms using a point source approximation. From these criteria we gathered a suite of 15 intraplate events. Synthetic seismograms of direct P-waves and depth phases are computed using a 1-D propagator matrix approach and compared with global teleseismic waveform data to determine a best depth for each event. To generate our synthetic seismograms we utilized the CRUST1.0 software, a global crustal <span class="hlt">model</span> that generates velocity values at the hypocenter of our events. Our waveform analysis results reveal that our depths diverge from the Global Centroid Moment Tensor (GCMT) depths, which underestimate our deep lithosphere events and overestimate our shallow depths by as much as 17 km. We determined a depth of 45km for our deepest event. We will show a comparison of our final <span class="hlt">earthquake</span> depths with the lithospheric thickness based on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20060040562&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DEarthquake','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20060040562&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DEarthquake"><span>Use of GPS and InSAR Technology and its Further Development in <span class="hlt">Earthquake</span> <span class="hlt">Modeling</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Donnellan, A.; Lyzenga, G.; Argus, D.; Peltzer, G.; Parker, J.; Webb, F.; Heflin, M.; Zumberge, J.</p> <p>1999-01-01</p> <p>Global Positioning System (GPS) data are useful for understanding both interseismic and postseismic deformation. <span class="hlt">Models</span> of GPS data suggest that the lower crust, lateral heterogeneity, and fault slip, all provide a role in the <span class="hlt">earthquake</span> cycle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993PhDT........51R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993PhDT........51R"><span>Simulational Studies of a 2-DIMENSIONAL Burridge - <span class="hlt">Model</span> for <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>Ross, John Bernard</p> <p>1993-01-01</p> <p>A two-dimensional cellular automaton version of the Burridge-Knopoff (BK) <span class="hlt">model</span> for <span class="hlt">earthquakes</span> is studied. The <span class="hlt">model</span> consists of a lattice of blocks connected by springs, subject to static friction and driven at a rate v by an externally applied force. A block ruptures provided that its total stress matches or exceeds static friction. The distance it moves is proportional to the total stress, alpha of which it releases to each of its neighbors and 1 - qalpha<=aves the system, where q is the number of neighbors. The BK <span class="hlt">model</span> with nearest neighbor (q = 4) and long range (q = 24) interactions is simulated for spatially uniform and random static friction on lattices with periodic, open, closed, and fixed boundary conditions. In the nearest neighbor <span class="hlt">model</span>, the system appears to have a spinodal critical point at v = v_{c} in all cases except for closed boundaries and uniform thresholds, where the system appears to be self-organized critical. The dynamics of the <span class="hlt">model</span> is always periodic or quasiperiodic for non-closed boundaries and uniform thresholds. The stress is "quantized" in multiples of the loader force in this case. A mean field theory is presented from which v _{c} and the dominant period of oscillation is derived, which agree well with the data. v_{c} varies inversely with the number of neighbors to which each blocks is attached and, as a result, goes to zero as the range of the springs goes to infinity. This is consistent with the behavior of a spinodal critical point as the range of interactions goes to infinity. The quasistatic limit of tectonic loading is thus recovered.</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('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 <span class="hlt">Modeling</span> 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 <span class="hlt">model</span> may affect estimates of <span class="hlt">earthquake</span> economic loss. Specifically, it focuses on the <span class="hlt">earthquake</span> source <span class="hlt">model</span> 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 <span class="hlt">model</span>, and explores the effect of hypothetical reductions in epistemic uncertainty in parts of the <span class="hlt">model</span>. For example, it addresses questions such as what would happen to the calculated loss distribution if the uncertainty in slip rate in the WG02 <span class="hlt">model</span> 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 <span class="hlt">models</span> or by better constraining the inherent randomness in <span class="hlt">earthquake</span> recurrence? The study does not consider the effect of reducing uncertainty in the hazard introduced through <span class="hlt">models</span> 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> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70004499','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70004499"><span>Estimating shaking-induced casualties and building damage for global <span class="hlt">earthquake</span> events: a proposed <span class="hlt">modelling</span> 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>So, Emily; Spence, Robin</p> <p>2013-01-01</p> <p>Recent <span class="hlt">earthquakes</span> such as the Haiti <span class="hlt">earthquake</span> of 12 January 2010 and the Qinghai <span class="hlt">earthquake</span> on 14 April 2010 have highlighted the importance of rapid estimation of casualties after the event for humanitarian response. Both of these events resulted in surprisingly high death tolls, casualties and survivors made homeless. In the Mw = 7.0 Haiti <span class="hlt">earthquake</span>, over 200,000 people perished with more than 300,000 reported injuries and 2 million made homeless. The Mw = 6.9 <span class="hlt">earthquake</span> in Qinghai resulted in over 2,000 deaths with a further 11,000 people with serious or moderate injuries and 100,000 people have been left homeless in this mountainous region of China. In such events relief efforts can be significantly benefitted by the availability of rapid estimation and mapping of expected casualties. This paper contributes to ongoing global efforts to estimate probable <span class="hlt">earthquake</span> casualties very rapidly after an <span class="hlt">earthquake</span> has taken place. The analysis uses the assembled empirical damage and casualty data in the Cambridge <span class="hlt">Earthquake</span> Impacts Database (CEQID) and explores data by event and across events to test the relationships of building and fatality distributions to the main explanatory variables of building type, building damage level and <span class="hlt">earthquake</span> intensity. The prototype global casualty estimation <span class="hlt">model</span> described here uses a semi-empirical approach that estimates damage rates for different classes of buildings present in the local building stock, and then relates fatality rates to the damage rates of each class of buildings. This approach accounts for the effect of the very different types of buildings (by climatic zone, urban or rural location, culture, income level etc), on casualties. The resulting casualty parameters were tested against the overall casualty data from several historical <span class="hlt">earthquakes</span> in CEQID; a reasonable fit was found.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AcSSn..18..290J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AcSSn..18..290J"><span>The December 26, 2004, off the west coast of northern Sumatra, Indonesia, M W=9.0, <span class="hlt">earthquake</span> and the critical-point-like <span class="hlt">model</span> of <span class="hlt">earthquake</span> preparation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jiang, Chang-Sheng; Wu, Zhong-Liang</p> <p>2005-05-01</p> <p>Long-term seismic activity prior to the December 26, 2004, off the west coast of northern Sumatra, Indonesia, M W=9.0 <span class="hlt">earthquake</span> was investigated using the Harvard CMT catalogue. It is observed that before this great <span class="hlt">earthquake</span>, there exists an accelerating moment release (AMR) process with the temporal scale of a quarter century and the spatial scale of 1 500 km. Within this spatial range, the M W=9.0 event falls into the piece-wise power-law-like frequency-magnitude distribution. Therefore, in the perspective of the critical-point-like <span class="hlt">model</span> of <span class="hlt">earthquake</span> preparation, the failure to forecast/predict the approaching and/or the size of this <span class="hlt">earthquake</span> is not due to the physically intrinsic unpredictability of <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.4990B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.4990B"><span>Local <span class="hlt">earthquake</span> tomography <span class="hlt">model</span> for the southern Dead Sea area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Braeuer, B.; Asch, G.; Hofstetter, R.; Haberland, Ch.; Jaser, D.; El-Kelani, R.; Weber, M.</p> <p>2012-04-01</p> <p>Local <span class="hlt">earthquake</span> data from a dense temporary seismological network in the southern Dead Sea area have been analyzed within the project DESIRE (Dead Sea Integrated Research Project). Local <span class="hlt">earthquakes</span> are used for the first precise image of the distribution of the P velocity and the vp/vs ratios. 65 stations registered 655 local events within 18 months of observation time. A subset of 530 well locatable events with 26,730 P- and S-arrival times was used to calculate a tomographic <span class="hlt">model</span> for the vp and vp/vs distribution. Since the study area is at first order two-dimensional, a gradual approach was chosen, which compromised a 2-D inversion followed by a 3-D inversion. The sedimentary basin fill, clearly imaged through high vp/vs ratios and low vp, shows an asymmetric structure with a vertical eastern boundary and an inclined western boundary. Within the basin fill the Lisan salt diapir is imaged through low vp/vs ratios. Below the basin fill the pre-basin sediments and the reworked crust, indicated by low P velocities and low vp/vs ratios, form a 10 km wide body between 12 and 18 km depth with vertical boundaries. No indications are found for a significant change of the P velocity structure in NS direction. Meanwhile, the change of the vp/vs ratios from high to low values varies in NS direction. This change, interpreted as the lower boundary of the basin fill, is reached already at 10 km depth in the area of the Boqeq fault, but not until 14 km depth below the Lisan peninsula. This difference is most likely related to different amounts of faulting at the transverse normal faults. North of the Boqeq fault the seismic activity between 3 and 15 km depth is mostly related to the fluid containing basin sediments. South of the Boqeq fault the seismic events occur between 12 and 18 km depth, and thus within the pre-basin sediments and the underlying crust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NPGeo..22..499V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NPGeo..22..499V"><span><span class="hlt">Earthquake</span> sequencing: chimera states with Kuramoto <span class="hlt">model</span> dynamics on directed graphs</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vasudevan, K.; Cavers, M.; Ware, A.</p> <p>2015-09-01</p> <p><span class="hlt">Earthquake</span> sequencing studies allow us to investigate empirical relationships among spatio-temporal parameters describing the complexity of <span class="hlt">earthquake</span> properties. We have recently studied the relevance of Markov chain <span class="hlt">models</span> to draw information from global <span class="hlt">earthquake</span> catalogues. In these studies, we considered directed graphs as graph theoretic representations of the Markov chain <span class="hlt">model</span> and analyzed their properties. Here, we look at <span class="hlt">earthquake</span> sequencing itself as a directed graph. In general, <span class="hlt">earthquakes</span> are occurrences resulting from significant stress interactions among faults. As a result, stress-field fluctuations evolve continuously. We propose that they are akin to the dynamics of the collective behavior of weakly coupled non-linear oscillators. Since mapping of global stress-field fluctuations in real time at all scales is an impossible task, we consider an <span class="hlt">earthquake</span> zone as a proxy for a collection of weakly coupled oscillators, the dynamics of which would be appropriate for the ubiquitous Kuramoto <span class="hlt">model</span>. In the present work, we apply the Kuramoto <span class="hlt">model</span> with phase lag to the non-linear dynamics on a directed graph of a sequence of <span class="hlt">earthquakes</span>. For directed graphs with certain properties, the Kuramoto <span class="hlt">model</span> yields synchronization, and inclusion of non-local effects evokes the occurrence of chimera states or the co-existence of synchronous and asynchronous behavior of oscillators. In this paper, we show how we build the directed graphs derived from global seismicity data. Then, we present conditions under which chimera states could occur and, subsequently, point out the role of the Kuramoto <span class="hlt">model</span> in understanding the evolution of synchronous and asynchronous regions. We surmise that one implication of the emergence of chimera states will lead to investigation of the present and other mathematical <span class="hlt">models</span> in detail to generate global chimera-state maps similar to global seismicity maps for <span class="hlt">earthquake</span> forecasting studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1437/g/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1437/g/"><span>Development of Final A-Fault Rupture <span class="hlt">Models</span> for WGCEP/ NSHMP <span class="hlt">Earthquake</span> Rate <span class="hlt">Model</span> 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, Edward H.; Weldon, Ray J.; Parsons, Thomas; Wills, Chris J.; Dawson, Timothy E.; Stein, Ross S.; Petersen, Mark D.</p> <p>2008-01-01</p> <p>This appendix discusses how we compute the magnitude and rate of <span class="hlt">earthquake</span> 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 <span class="hlt">Earthquake</span> Rate <span class="hlt">Model</span> 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 <span class="hlt">models</span>, where ruptures are assumed be confined to one or more identifiable segments. The second section discusses an un-segmented-<span class="hlt">model</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....8860S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....8860S"><span>Fault geometry of Vesuvius <span class="hlt">earthquakes</span> from revised tomographic <span class="hlt">models</span> and accurate <span class="hlt">earthquake</span> relocations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Scarpa, R.; del Pezzo, E.; Bianco, F.; Saccorotti, G.; Tronca, F.</p> <p>2003-04-01</p> <p>A high resolution P-wave image of Mt. Vesuvius edifice has been derived from simultaneous inversion of travel times and hypocentral parameters of local <span class="hlt">earthquakes</span>, land based shots and small aperture array data. The resulting image is resolved to 300-500 m block size. The relocated local seismicity appears to extend down to 5 km below the central crater, distributed in a major cluster, centered at 3 km below the central crater and in a minor group, with diffuse hypocenters inside the volcanic edifice. The two clusters are separated by an anomalously high Vp region at around 1 km depth. A zone with high Vp/Vs in the upper layers is interpreted as produced by the presence of intense fluid circulation. The highest energy quakes (up to M=3.6) are located in the deeper cluster, in a high P-wave velocity zone. Our results favor an interpretation in terms of absence of shallow magma reservoirs. Fault plane solutions, obtained in the hypothesis of double couple mechanism, show unstable solutions with no preferential trend. This is possibly due to the unfavourable signal to noise ratio affecting the first motion pulse direction estimates. The occurrence of similar <span class="hlt">earthquakes</span> (multiplets) greatly helps in evidencing the trend of the main faults of the investigated area. We grouped similar <span class="hlt">earthquakes</span> into several different families using the Equivalence Class approach. For each family, we use interpolated correlation analyses to estimate the time shifts among the different members of the family with respect to a principal event selected as the master one. Least-squares adjustment of arrival times provide consistency of these estimates throughout the different members of the cluster. This refined set of arrival times is then used to relocate events belonging to individual clusters using a non-linear, probabilistic technique acting on the 3-D heterogeneous earth structure. The high similarity of waveforms for events belonging to different families is associated to similar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GGG....17.2700D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GGG....17.2700D"><span>Geodetically constrained <span class="hlt">models</span> of viscoelastic stress transfer and <span class="hlt">earthquake</span> triggering along the North Anatolian fault</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>DeVries, Phoebe M. R.; Krastev, Plamen G.; Meade, Brendan J.</p> <p>2016-07-01</p> <p>Over the past 80 years, 8 MW > 6.7 strike-slip <span class="hlt">earthquakes</span> west of 40° longitude have ruptured the North Anatolian fault (NAF) from east to west. The series began with the 1939 Erzincan <span class="hlt">earthquake</span> in eastern Turkey, and the most recent 1999 MW = 7.4 Izmit <span class="hlt">earthquake</span> extended the pattern of ruptures into the Sea of Marmara in western Turkey. The mean time between seismic events in this westward progression is 8.5 ± 11 years (67% confidence interval), much greater than the timescale of seismic wave propagation (seconds to minutes). The delayed triggering of these <span class="hlt">earthquakes</span> may be explained by the propagation of <span class="hlt">earthquake</span>-generated diffusive viscoelastic fronts within the upper mantle that slowly increase the Coulomb failure stress change (ΔCFS) at adjacent hypocenters. Here we develop three-dimensional stress transfer <span class="hlt">models</span> with an elastic upper crust coupled to a viscoelastic Burgers rheology mantle. Both the Maxwell (ηM = 4 × 1018-1 × 1019 Pa s) and Kelvin (ηK = 1 × 1018-1 × 1019 Pa s) viscosities are constrained by studies of geodetic observations before and after the 1999 Izmit <span class="hlt">earthquake</span>. We combine this geodetically constrained rheological <span class="hlt">model</span> with the observed sequence of large <span class="hlt">earthquakes</span> since 1939 to calculate the time evolution of ΔCFS changes along the North Anatolian fault due to viscoelastic stress transfer. Apparent threshold values of mean ΔCFS at which the <span class="hlt">earthquakes</span> in the eight decade sequence occur are between ˜0.02 to ˜3.15 MPa and may exceed the magnitude of static ΔCFS values by as much as 177%. By 2023, we infer that the mean time-dependent stress change along the northern NAF strand in the Marmara Sea near Istanbul, which may have previously ruptured in 1766, may reach the mean apparent time-dependent stress thresholds of the previous NAF <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S31B2730X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S31B2730X"><span>Aftershocks Decays of the 2015 Gorkha Nepal <span class="hlt">earthquake</span> and the 2008 Wenchuan China <span class="hlt">earthquake</span>: Observation, <span class="hlt">Modeling</span> and Implication</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xie, M.; Shi, B.</p> <p>2016-12-01</p> <p>To obtain the knowledge of <span class="hlt">earthquake</span> process, we need enough information from both experiments and observations. Among all kinds of observations, the locations and timing of the aftershock sequences from mainshocks could tell us some useful clues. The 2015 Gorkha Nepal <span class="hlt">earthquake</span> (GNE) and the 2008 Wenchuan China <span class="hlt">earthquake</span> (WCE) sequences occurred in the southern and eastern margins of Qinghai-Tibetan Plateau, respectively. Because the seismotectonic settings in Nepal and Tibet are broadly similar and their mainshock magnitudes are comparable, by using the regional seismicity data and the aftershock catalogs from the USGS and NEIC for these two events, we explored the spatio-temporal characteristics of aftershocks to gain insight into the possible fault frictional processes related to their triggering mechanisms. First, we estimated the minimum magnitude of complete recording for these two sequences within 0.1day. For this period, the magnitude of completeness Mc is estimated to 4.0 by using a maximum likelihood procedure. Then, we fit the seismicity decay both with the empirical and physical <span class="hlt">models</span>. Our current results indicate that, compared with the WCE sequence, the number of aftershocks is much smaller, and the aftershock duration is also shorter for the GNE sequence. Additionally, for these two sequences the p-value used to describe the aftershock decay rate given by the Modified Omori Law (MOL) is obviously large than 1 which is in contradiction with the static stress triggering <span class="hlt">model</span> (Dieterich, 1994). Based on the Dieterich seismicity evolution <span class="hlt">model</span> and the rate- and state-dependent friction law (RSF), we propose that the afterslip behavior could be a possible candidate to explain such kind of aftershock decays. The current results indicate that, with a constant background stress rate, the p > 1 could be well explained and fitted for events M > 4.0 if a postseismic stress rate change is involved in the <span class="hlt">model</span> fitting. Moreover, the p-value is connected</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70013903','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70013903"><span>Instability <span class="hlt">model</span> for recurring large and great <span class="hlt">earthquakes</span> in 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>Stuart, W.D.</p> <p>1985-01-01</p> <p>The locked section of the San Andreas fault in southern California has experienced a number of large and great <span class="hlt">earthquakes</span> in the past, and thus is expected to have more in the future. To estimate the location, time, and slip of the next few <span class="hlt">earthquakes</span>, an <span class="hlt">earthquake</span> instability <span class="hlt">model</span> is formulated. The <span class="hlt">model</span> is similar to one recently developed for moderate <span class="hlt">earthquakes</span> on the San Andreas fault near Parkfield, California. In both <span class="hlt">models</span>, unstable faulting (the <span class="hlt">earthquake</span> analog) is caused by failure of all or part of a patch of brittle, strain-softening fault zone. In the present <span class="hlt">model</span> the patch extends downward from the ground surface to about 12 km depth, and extends 500 km along strike from Parkfield to the Salton Sea. The variation of patch strength along strike is adjusted by trial until the computed sequence of instabilities matches the sequence of large and great <span class="hlt">earthquakes</span> since a.d. 1080 reported by Sieh and others. The last <span class="hlt">earthquake</span> was the M=8.3 Ft. Tejon event in 1857. The resulting strength variation has five contiguous sections of alternately low and high strength. From north to south, the approximate locations of the sections are: (1) Parkfield to Bitterwater Valley, (2) Bitterwater Valley to Lake Hughes, (3) Lake Hughes to San Bernardino, (4) San Bernardino to Palm Springs, and (5) Palm Springs to the Salton Sea. Sections 1, 3, and 5 have strengths between 53 and 88 bars; sections 2 and 4 have strengths between 164 and 193 bars. Patch section ends and unstable rupture ends usually coincide, although one or more adjacent patch sections may fail unstably at once. The <span class="hlt">model</span> predicts that the next sections of the fault to slip unstably will be 1, 3, and 5; the order and dates depend on the assumed length of an <span class="hlt">earthquake</span> rupture in about 1700. ?? 1985 Birkha??user Verlag.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70036770','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70036770"><span>An Atlas of ShakeMaps and population exposure catalog for <span class="hlt">earthquake</span> loss <span class="hlt">modeling</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>Allen, T.I.; Wald, D.J.; Earle, P.S.; Marano, K.D.; Hotovec, A.J.; Lin, K.; Hearne, M.G.</p> <p>2009-01-01</p> <p>We present an Atlas of ShakeMaps and a catalog of human population exposures to moderate-to-strong ground shaking (EXPO-CAT) for recent historical <span class="hlt">earthquakes</span> (1973-2007). The common purpose of the Atlas and exposure catalog is to calibrate <span class="hlt">earthquake</span> loss <span class="hlt">models</span> to be used in the US Geological Survey's Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER). The full ShakeMap Atlas currently comprises over 5,600 <span class="hlt">earthquakes</span> from January 1973 through December 2007, with almost 500 of these maps constrained-to varying degrees-by instrumental ground motions, macroseismic intensity data, community internet intensity observations, and published <span class="hlt">earthquake</span> rupture <span class="hlt">models</span>. The catalog of human exposures is derived using current PAGER methodologies. Exposure to discrete levels of shaking intensity is obtained by correlating Atlas ShakeMaps with a global population database. Combining this population exposure dataset with historical <span class="hlt">earthquake</span> loss data, such as PAGER-CAT, provides a useful resource for calibrating loss methodologies against a systematically-derived set of ShakeMap hazard outputs. We illustrate two example uses for EXPO-CAT; (1) simple objective ranking of country vulnerability to <span class="hlt">earthquakes</span>, and; (2) the influence of time-of-day on <span class="hlt">earthquake</span> mortality. In general, we observe that countries in similar geographic regions with similar construction practices tend to cluster spatially in terms of relative vulnerability. We also find little quantitative evidence to suggest that time-of-day is a significant factor in <span class="hlt">earthquake</span> mortality. Moreover, <span class="hlt">earthquake</span> mortality appears to be more systematically linked to the population exposed to severe ground shaking (Modified Mercalli Intensity VIII+). Finally, equipped with the full Atlas of ShakeMaps, we merge each of these maps and find the maximum estimated peak ground acceleration at any grid point in the world for the past 35 years. We subsequently compare this "composite ShakeMap" with existing global</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AIPC.1857j0011R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AIPC.1857j0011R"><span>Spatial <span class="hlt">modeling</span> for estimation of <span class="hlt">earthquakes</span> economic loss in West Java</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Retnowati, Dyah Ayu; Meilano, Irwan; Riqqi, Akhmad; Hanifa, Nuraini Rahma</p> <p>2017-07-01</p> <p>Indonesia has a high vulnerability towards <span class="hlt">earthquakes</span>. The low adaptive capacity could make the <span class="hlt">earthquake</span> become disaster that should be concerned. That is why risk management should be applied to reduce the impacts, such as estimating the economic loss caused by hazard. The study area of this research is West Java. The main reason of West Java being vulnerable toward <span class="hlt">earthquake</span> is the existence of active faults. These active faults are Lembang Fault, Cimandiri Fault, Baribis Fault, and also Megathrust subduction zone. This research tries to estimates the value of <span class="hlt">earthquakes</span> economic loss from some sources in West Java. The economic loss is calculated by using HAZUS method. The components that should be known are hazard (<span class="hlt">earthquakes</span>), exposure (building), and the vulnerability. Spatial <span class="hlt">modeling</span> is aimed to build the exposure data and make user get the information easier by showing the distribution map, not only in tabular data. As the result, West Java could have economic loss up to 1,925,122,301,868,140 IDR ± 364,683,058,851,703.00 IDR, which is estimated from six <span class="hlt">earthquake</span> sources with maximum possibly magnitude. However, the estimation of economic loss value in this research is the worst case <span class="hlt">earthquakes</span> occurrence which is probably over-estimated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19518296','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19518296"><span><span class="hlt">Earthquake</span> size-frequency statistics in a forest-fire <span class="hlt">model</span> of individual faults.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tejedor, Alejandro; Gómez, Javier B; Pacheco, Amalio F</p> <p>2009-04-01</p> <p>The <span class="hlt">earthquake</span> size-frequency distribution of individual seismic faults commonly differs from the Gutenberg-Richter law of regional seismicity by the presence of an excess of large <span class="hlt">earthquakes</span>. Here we present a cellular automaton of the forest-fire <span class="hlt">model</span> type that is able to reproduce several size-frequency distributions depending on the number and location of asperities on the fault plane. The <span class="hlt">model</span> describes a fault plane as a two-dimensional array of cells where each cell can be either a normal site or a trigger site. <span class="hlt">Earthquakes</span> start on trigger sites. Asperities appear as the dual entities of the trigger sites. We study the effect that the number and distribution of asperities (the dual of the set of trigger sites), the <span class="hlt">earthquake</span> rate, and the aspect ratio of the fault have on the size-frequency distribution. Size-frequency distributions have been grouped into subcritical, critical, and supercritical, and the relationship between the <span class="hlt">model</span> parameters and these three kinds of distributions is presented in the form of phase maps for each of the five asperity types tested. We also study the connection between the <span class="hlt">model</span> parameters and the aperiodicity of the large <span class="hlt">earthquakes</span>. For this purpose the concept of aperiodicity spectrum is introduced. The aperiodicity in the recurrence of the large <span class="hlt">earthquakes</span> in a fault shows an interesting variability that can be potentially useful for prediction purposes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1911937K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1911937K"><span>Preliminary <span class="hlt">modeling</span> of turbidity currents associated with 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>Kioka, Arata; Strasser, Michael; Moernaut, Jasper; Schwestermann, Tobias; Ikehara, Ken; Kanamatsu, Toshiya; McHugh, Cecilia M.</p> <p>2017-04-01</p> <p>The 2011 Tohoku-oki <span class="hlt">earthquake</span> generated among the largest volume of sediment transportation associated with coseismic shaking, tsunamis, and submarine landslides. Several recent studies of sediment cores, and instrumental observations revealed that the 2011 <span class="hlt">earthquake</span> mobilized sediments to transport along the slope and over to the Japan Trench through single or multi-flow turbidity currents. Yet, source location and flow pathways of turbidity currents associated with the 2011 <span class="hlt">earthquake</span>, and the resulting spatial distribution of deposit thickness remain unknown. Here we <span class="hlt">model</span> three-dimensional depth-averaged turbidity currents offshore Tohoku area, to investigate possible scenarios of source location, flow size, and pathways of turbidity currents generated by the 2011 <span class="hlt">earthquake</span>. Within the studied <span class="hlt">model</span> scheme, the <span class="hlt">model</span> is theoretically hampered to produce reliable results because of large uncertainties in parameters including seabed conditions and flow properties. In our <span class="hlt">modelling</span>, sediment cores and subbottom profiles acquired from research cruises after the 2011 <span class="hlt">earthquake</span> (e.g., R/V Sonne SO251A), and previous results are used to constrain most of the parameters. We also test a sensitivity of the parameters in order to examine how the sediment dynamics in Japan Trench changes with different properties of the flow. Our scheme also helps further our understanding of turbidite system produced by old giant <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6710795','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6710795"><span>Crack fusion dynamics: A <span class="hlt">model</span> for large <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Newman, W.I.; Knopoff, L.</p> <p>1982-07-01</p> <p>The physical processes of the fusion of small cracks into larger ones are nonlinear in character. A study of the nonlinear properties of fusion may lead to an understanding of the instabilities that give rise to clustering of large <span class="hlt">earthquakes</span>. We have investigated the properties of simple versions of fusion processes to see if instabilities culminating in repetitive massive <span class="hlt">earthquakes</span> are possible. We have taken into account such diverse phenomena as the production of aftershocks, the rapid extension of large cracks to overwhelm and absorb smaller cracks, the influence of anelastic creep-induced time delays, healing, the genesis of ''juvenile'' cracks due to plate motions, and others. A preliminary conclusion is that the time delays introduced by anelastic creep may be responsible for producing catastrophic instabilities characteristic of large <span class="hlt">earthquakes</span> as well as aftershock sequences. However, it seems that nonlocal influences, i.e., the spatial diffusion of cracks, may play a dominant role in producing episodes of seismicity and clustering.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/tm/12b1/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/tm/12b1/"><span>SLAMMER: Seismic LAndslide Movement <span class="hlt">Modeled</span> using <span class="hlt">Earthquake</span> Records</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jibson, Randall W.; Rathje, Ellen M.; Jibson, Matthew W.; Lee, Yong W.</p> <p>2013-01-01</p> <p>This program is designed to facilitate conducting sliding-block analysis (also called permanent-deformation analysis) of slopes in order to estimate slope behavior during <span class="hlt">earthquakes</span>. The program allows selection from among more than 2,100 strong-motion records from 28 <span class="hlt">earthquakes</span> and allows users to add their own records to the collection. Any number of <span class="hlt">earthquake</span> records can be selected using a search interface that selects records based on desired properties. Sliding-block analyses, using any combination of rigid-block (Newmark), decoupled, and fully coupled methods, are then conducted on the selected group of records, and results are compiled in both graphical and tabular form. Simplified methods for conducting each type of analysis are also included.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.211..239S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.211..239S"><span>Prospective and retrospective evaluation of five-year <span class="hlt">earthquake</span> forecast <span class="hlt">models</span> for California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Strader, Anne; Schneider, Max; Schorlemmer, Danijel</p> <p>2017-10-01</p> <p>The Collaboratory for the Study of <span class="hlt">Earthquake</span> Predictability was developed to prospectively test <span class="hlt">earthquake</span> forecasts through reproducible and transparent experiments within a controlled environment. From January 2006 to December 2010, the Regional <span class="hlt">Earthquake</span> Likelihood <span class="hlt">Models</span> (RELM) Working Group developed and evaluated thirteen time-invariant prospective <span class="hlt">earthquake</span> mainshock forecasts. The number, spatial and magnitude components of the forecasts were compared to the observed seismicity distribution using a set of likelihood-based consistency tests. In this RELM experiment update, we assess the long-term forecasting potential of the RELM forecasts. Additionally, we evaluate RELM forecast performance against the Uniform California <span class="hlt">Earthquake</span> Rupture Forecast (UCERF2) and the National Seismic Hazard Mapping Project (NSHMP) forecasts, which are used for seismic hazard analysis for California. To test each forecast's long-term stability, we also evaluate each forecast from January 2006 to December 2015, which contains both five-year testing periods, and the 40-year period from January 1967 to December 2006. Multiple RELM forecasts, which passed the N-test during the retrospective (January 2006 to December 2010) period, overestimate the number of events from January 2011 to December 2015, although their forecasted spatial distributions are consistent with observed <span class="hlt">earthquakes</span>. Both the UCERF2 and NSHMP forecasts pass all consistency tests for the two five-year periods; however, they tend to underestimate the number of observed <span class="hlt">earthquakes</span> over the 40-year testing period. The smoothed seismicity <span class="hlt">model</span> Helmstetter-et-al.Mainshock outperforms both United States Geological Survey (USGS) <span class="hlt">models</span> during the second five-year experiment, and contains higher forecasted seismicity rates than the USGS <span class="hlt">models</span> at multiple observed <span class="hlt">earthquake</span> locations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S22B..06M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S22B..06M"><span>Combining Multiple Rupture <span class="hlt">Models</span> in Real-Time for <span class="hlt">Earthquake</span> Early Warning</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Minson, S. E.; Wu, S.; Beck, J. L.; Heaton, T. H.</p> <p>2015-12-01</p> <p>The ShakeAlert <span class="hlt">earthquake</span> early warning system for the west coast of the United States is designed to combine information from multiple independent <span class="hlt">earthquake</span> analysis algorithms in order to provide the public with robust predictions of shaking intensity at each user's location before they are affected by strong shaking. The current contributing analyses come from algorithms that determine the origin time, epicenter, and magnitude of an <span class="hlt">earthquake</span> (On-site, ElarmS, and Virtual Seismologist). A second generation of algorithms will provide seismic line source information (FinDer), as well as geodetically-constrained slip <span class="hlt">models</span> (BEFORES, GPSlip, G-larmS, G-FAST). These new algorithms will provide more information about the spatial extent of the <span class="hlt">earthquake</span> rupture and thus improve the quality of the resulting shaking forecasts.Each of the contributing algorithms exploits different features of the observed seismic and geodetic data, and thus each algorithm may perform differently for different data availability and <span class="hlt">earthquake</span> source characteristics. Thus the ShakeAlert system requires a central mediator, called the Central Decision Module (CDM). The CDM acts to combine disparate <span class="hlt">earthquake</span> source information into one unified shaking forecast. Here we will present a new design for the CDM that uses a Bayesian framework to combine <span class="hlt">earthquake</span> reports from multiple analysis algorithms and compares them to observed shaking information in order to both assess the relative plausibility of each <span class="hlt">earthquake</span> report and to create an improved unified shaking forecast complete with appropriate uncertainties. We will describe how these probabilistic shaking forecasts can be used to provide each user with a personalized decision-making tool that can help decide whether or not to take a protective action (such as opening fire house doors or stopping trains) based on that user's distance to the <span class="hlt">earthquake</span>, vulnerability to shaking, false alarm tolerance, and time required to act.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH54B..02C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH54B..02C"><span>Short- and Long-Term <span class="hlt">Earthquake</span> Forecasts Based on Statistical <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Console, R.; Murru, M.; Falcone, G.; Marzocchi, W.</p> <p>2016-12-01</p> <p>The epidemic-type aftershock sequences (ETAS) <span class="hlt">models</span> have been experimentally used to forecast the space-time <span class="hlt">earthquake</span> occurrence rate during the sequence that followed the 2009 L'Aquila <span class="hlt">earthquake</span> and for the 2012 Emilia <span class="hlt">earthquake</span> sequence. These forecasts represented the two first pioneering attempts to check the feasibility of providing operational <span class="hlt">earthquake</span> forecasting (OEF) in Italy. After the 2009 L'Aquila <span class="hlt">earthquake</span> the Italian Department of Civil Protection nominated an International Commission on <span class="hlt">Earthquake</span> Forecasting (ICEF) for the development of the first official OEF in Italy that was implemented for testing purposes by the newly established "Centro di Pericolosità Sismica" (CPS, the seismic Hazard Center) at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). According to the ICEF guidelines, the system is open, transparent, reproducible and testable. The scientific information delivered by OEF-Italy is shaped in different formats according to the interested stakeholders, such as scientists, national and regional authorities, and the general public. The communication to people is certainly the most challenging issue, and careful pilot tests are necessary to check the effectiveness of the communication strategy, before opening the information to the public. With regard to long-term time-dependent <span class="hlt">earthquake</span> forecast, the application of a newly developed simulation algorithm to Calabria region provided typical features in time, space and magnitude behaviour of the seismicity, which can be compared with those of the real observations. These features include long-term pseudo-periodicity and clustering of strong <span class="hlt">earthquakes</span>, and a realistic <span class="hlt">earthquake</span> magnitude distribution departing from the Gutenberg-Richter distribution in the moderate and higher magnitude range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1919030C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1919030C"><span>Short- and Long-Term <span class="hlt">Earthquake</span> Forecasts Based on Statistical <span class="hlt">Models</span></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; Taroni, Matteo; Murru, Maura; Falcone, Giuseppe; Marzocchi, Warner</p> <p>2017-04-01</p> <p>The epidemic-type aftershock sequences (ETAS) <span class="hlt">models</span> have been experimentally used to forecast the space-time <span class="hlt">earthquake</span> occurrence rate during the sequence that followed the 2009 L'Aquila <span class="hlt">earthquake</span> and for the 2012 Emilia <span class="hlt">earthquake</span> sequence. These forecasts represented the two first pioneering attempts to check the feasibility of providing operational <span class="hlt">earthquake</span> forecasting (OEF) in Italy. After the 2009 L'Aquila <span class="hlt">earthquake</span> the Italian Department of Civil Protection nominated an International Commission on <span class="hlt">Earthquake</span> Forecasting (ICEF) for the development of the first official OEF in Italy that was implemented for testing purposes by the newly established "Centro di Pericolosità Sismica" (CPS, the seismic Hazard Center) at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). According to the ICEF guidelines, the system is open, transparent, reproducible and testable. The scientific information delivered by OEF-Italy is shaped in different formats according to the interested stakeholders, such as scientists, national and regional authorities, and the general public. The communication to people is certainly the most challenging issue, and careful pilot tests are necessary to check the effectiveness of the communication strategy, before opening the information to the public. With regard to long-term time-dependent <span class="hlt">earthquake</span> forecast, the application of a newly developed simulation algorithm to Calabria region provided typical features in time, space and magnitude behaviour of the seismicity, which can be compared with those of the real observations. These features include long-term pseudo-periodicity and clustering of strong <span class="hlt">earthquakes</span>, and a realistic <span class="hlt">earthquake</span> magnitude distribution departing from the Gutenberg-Richter distribution in the moderate and higher magnitude range.</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/2015ESS.....310909T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ESS.....310909T"><span>"Slimplectic" Integrators: Variational Integrators for General <span class="hlt">Nonconservative</span> Dynamics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tsang, David</p> <p>2015-12-01</p> <p>Symplectic integrators are widely used for long-term integration of conservative astrophysical problems due to their ability to preserve the constants of motion; however, they cannot in general be applied in the presence of <span class="hlt">nonconservative</span> (e.g. dissipative) interactions. Here we present the “slimplectic” integrator, a new type of numerical integrator that shares many of the benefits of traditional symplectic integrators yet is applicable to general <span class="hlt">nonconservative</span> systems. We utilize a fixed-time-step variational integrator formalism applied to the recently developed principle of stationary <span class="hlt">nonconservative</span> action. As a result, the generalized momenta and energy (Noether current) evolutions are well-tracked. Slimplectic integrators are well-suited for integrations of systems where <span class="hlt">nonconservative</span> effects play an important role in the long-term dynamical evolution. As such they are particularly appropriate for cosmological or celestial N-body dynamics problems where <span class="hlt">nonconservative</span> interactions, e.g., PR drag, gas interactions, or dissipative tides, can play an important role</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22518911','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22518911"><span>“SLIMPLECTIC” INTEGRATORS: VARIATIONAL INTEGRATORS FOR GENERAL <span class="hlt">NONCONSERVATIVE</span> SYSTEMS</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Tsang, David; Turner, Alec; Galley, Chad R.; Stein, Leo C.</p> <p>2015-08-10</p> <p>Symplectic integrators are widely used for long-term integration of conservative astrophysical problems due to their ability to preserve the constants of motion; however, they cannot in general be applied in the presence of <span class="hlt">nonconservative</span> interactions. In this Letter, we develop the “slimplectic” integrator, a new type of numerical integrator that shares many of the benefits of traditional symplectic integrators yet is applicable to general <span class="hlt">nonconservative</span> systems. We utilize a fixed-time-step variational integrator formalism applied to the principle of stationary <span class="hlt">nonconservative</span> action developed in Galley et al. As a result, the generalized momenta and energy (Noether current) evolutions are well-tracked. We discuss several example systems, including damped harmonic oscillators, Poynting–Robertson drag, and gravitational radiation reaction, by utilizing our new publicly available code to demonstrate the slimplectic integrator algorithm. Slimplectic integrators are well-suited for integrations of systems where <span class="hlt">nonconservative</span> effects play an important role in the long-term dynamical evolution. As such they are particularly appropriate for cosmological or celestial N-body dynamics problems where <span class="hlt">nonconservative</span> interactions, e.g., gas interactions or dissipative tides, can play an important role.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUSM.U53A..02C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUSM.U53A..02C"><span><span class="hlt">Modeling</span> And Economics Of Extreme Subduction <span class="hlt">Earthquakes</span>: Two Case Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chavez, M.; Cabrera, E.; Emerson, D.; Perea, N.; Moulinec, C.</p> <p>2008-05-01</p> <p>The destructive effects of large magnitude, thrust subduction superficial (TSS) <span class="hlt">earthquakes</span> on Mexico City (MC) and Guadalajara (G) has been shown in the recent centuries. For example, the 7/04/1845 and the 19/09/1985, two TSS <span class="hlt">earthquakes</span> occurred on the coast of the state of Guerrero and Michoacan, with Ms 7+ and 8.1. The economical losses for the later were of about 7 billion US dollars. Also, the largest Ms 8.2, instrumentally observed TSS <span class="hlt">earthquake</span> in Mexico, occurred in the Colima-Jalisco region the 3/06/1932, and the 9/10/1995 another similar, Ms 7.4 event occurred in the same region, the later produced economical losses of hundreds of thousands US dollars.The frequency of occurrence of large TSS <span class="hlt">earthquakes</span> in Mexico is poorly known, but it might vary from decades to centuries [1]. Therefore there is a lack of strong ground motions records for extreme TSS <span class="hlt">earthquakes</span> in Mexico, which as mentioned above, recently had an important economical impact on MC and potentially could have it in G. In this work we obtained samples of broadband synthetics [2,3] expected in MC and G, associated to extreme (plausible) magnitude Mw 8.5, TSS scenario <span class="hlt">earthquakes</span>, with epicenters in the so-called Guerrero gap and in the Colima-Jalisco zone, respectively. The economical impacts of the proposed extreme TSS <span class="hlt">earthquake</span> scenarios for MC and G were considered as follows: For MC by using a risk acceptability criteria, the probabilities of exceedance of the maximum seismic responses of their construction stock under the assumed scenarios, and the estimated economical losses observed for the 19/09/1985 <span class="hlt">earthquake</span>; and for G, by estimating the expected economical losses, based on the seismic vulnerability assessment of their construction stock under the extreme seismic scenario considered. ----------------------- [1] Nishenko S.P. and Singh SK, BSSA 77, 6, 1987 [2] Cabrera E., Chavez M., Madariaga R., Mai M, Frisenda M., Perea N., AGU, Fall Meeting, 2005 [3] Chavez M., Olsen K</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.S53C4531N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S53C4531N"><span>Space-time Renewal <span class="hlt">Model</span> for Repeating <span class="hlt">Earthquakes</span> and Slow Slip before and after the Major <span class="hlt">Earthquakes</span> in the Northeastern Japan 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>Nomura, S.; Ogata, Y.; Uchida, N.</p> <p>2014-12-01</p> <p>Repeating <span class="hlt">earthquake</span> sequences on the plate subduction zone represent the slip-rate histories around their fault patches. So they are useful resources for monitoring precursory aseismic slip of major <span class="hlt">earthquakes</span> on plate boundaries. Repeating <span class="hlt">earthquakes</span> are often <span class="hlt">modeled</span> by renewal processes, point processes whose recurrence intervals are independent and identically distributed. However, their repeating intervals are greatly influenced by larger seismic events or aseismic slow slip, and hence we need to <span class="hlt">model</span> such non-stationary behavior of repeating <span class="hlt">earthquakes</span>. In this study, we propose a non-stationary space-time <span class="hlt">model</span> for repeating <span class="hlt">earthquakes</span> based on the <span class="hlt">model</span> in Nomura et al. (2014) applied to the Parkfield catalog. We used the empirical relation between magnitudes and slip sizes of repeating <span class="hlt">earthquakes</span> by Nadeau and Johnson (1998) to estimate the slip-rate histories in repeating sequences. The proposed <span class="hlt">model</span> can estimate spatio-temporal variation in slip rate with smoothness restriction adjusted to optimize its Bayesian likelihood.We apply the proposed <span class="hlt">model</span> to the large catalog of repeating <span class="hlt">earthquakes</span> in Uchida and Matsuzawa (2013) on subduction zone of Pacific Plate in the northeastern Japan from 1993 to 2011 and estimate slip-rate history of the plate boundary. From this analysis, we discuss the characteristic changes in slip rate before and after the major <span class="hlt">earthquakes</span> such as Sanriku-Haruka-Oki (1994 Mw7.6), Tokachi-Oki (2003 Mw8.0), Kushiro-Oki (2004 Mw7.1), Fukushima-Oki (2008 Mw6.9), Ibaraki-Oki (2008 Mw7.0) and Tohoku-Oki (2011 Mw9.0).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.205..236X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.205..236X"><span>An improved geodetic source <span class="hlt">model</span> for the 1999 Mw 6.3 Chamoli <span class="hlt">earthquake</span>, India</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Wenbin; Bürgmann, Roland; Li, Zhiwei</p> <p>2016-04-01</p> <p>We present a distributed slip <span class="hlt">model</span> for the 1999 Mw 6.3 Chamoli <span class="hlt">earthquake</span> of north India using interferometric synthetic aperture radar (InSAR) data from both ascending and descending orbits and Bayesian estimation of confidence levels and trade-offs of the <span class="hlt">model</span> geometry parameters. The results of fault-slip inversion in an elastic half-space show that the <span class="hlt">earthquake</span> ruptured a 9°_{-2.2}^{+3.4} northeast-dipping plane with a maximum slip of ˜1 m. The fault plane is located at a depth of ˜15.9_{ - 3.0}^{ + 1.1} km and is ˜120 km north of the Main Frontal Thrust, implying that the rupture plane was on the northernmost detachment near the mid-crustal ramp of the Main Himalayan Thrust. The InSAR-determined moment is 3.35 × 1018 Nm with a shear modulus of 30 GPa, equivalent to Mw 6.3, which is smaller than the seismic moment estimates of Mw 6.4-6.6. Possible reasons for this discrepancy include the trade-off between moment and depth, uncertainties in seismic moment tensor components for shallow dip-slip <span class="hlt">earthquakes</span> and the role of earth structure <span class="hlt">models</span> in the inversions. The released seismic energy from recent <span class="hlt">earthquakes</span> in the Garhwal region is far less than the accumulated strain energy since the 1803 Ms 7.5 <span class="hlt">earthquake</span>, implying substantial hazard of future great <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.174....1S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.174....1S"><span>A Review of Source <span class="hlt">Models</span> of the 2015 Illapel, Chile <span class="hlt">Earthquake</span> and Insights from Tsunami Data</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; Heidarzadeh, Mohammad</p> <p>2017-01-01</p> <p>The 16 September 2015 Illapel, Chile, <span class="hlt">earthquake</span> and associated tsunami have been studied by many researchers from various aspects. This paper reviews studies on the source <span class="hlt">model</span> of the <span class="hlt">earthquake</span> and examines tsunami data. The Illapel <span class="hlt">earthquake</span> occurred in the source region of previous <span class="hlt">earthquakes</span> in 1943 and 1880. The <span class="hlt">earthquake</span> source was studied using various geophysical data, such as near-field seismograms, teleseismic waveform and backprojection, GPS and InSAR data, and tsunami waveforms. Most seismological analyses show a duration of 100 s with a peak at 50 s. The spatial distribution has some variety, but they all have the largest slip varying from 5 to 16 m located at 31°S, 72°W, which is 70 km NW of the epicenter. The shallow slip seems to be extended to the trench axis. A deeper slip patch was proposed from high-frequency seismic data. A tsunami <span class="hlt">earthquake</span> <span class="hlt">model</span> with a total duration of 250 s and a third asperity south of the epicenter is also proposed, but we show that the tsunami data do not support this <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.8816S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.8816S"><span>Facilitating open global data use in <span class="hlt">earthquake</span> source <span class="hlt">modelling</span> to improve geodetic and seismological approaches</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sudhaus, Henriette; Heimann, Sebastian; Steinberg, Andreas; Isken, Marius; Vasyura-Bathke, Hannes</p> <p>2017-04-01</p> <p>In the last few years impressive achievements have been made in improving inferences about <span class="hlt">earthquake</span> sources by using InSAR (Interferometric Synthetic Aperture Radar) data. Several factors aided these developments. The open data basis of <span class="hlt">earthquake</span> observations has expanded vastly with the two powerful Sentinel-1 SAR sensors up in space. Increasing computer power allows processing of large data sets for more detailed source <span class="hlt">models</span>. Moreover, data inversion approaches for <span class="hlt">earthquake</span> source inferences are becoming more advanced. By now data error propagation is widely implemented and the estimation of <span class="hlt">model</span> uncertainties is a regular feature of reported optimum <span class="hlt">earthquake</span> source <span class="hlt">models</span>. Also, more regularly InSAR-derived surface displacements and seismological waveforms are combined, which requires finite rupture <span class="hlt">models</span> instead of point-source approximations and layered medium <span class="hlt">models</span> instead of homogeneous half-spaces. In other words the disciplinary differences in geodetic and seismological <span class="hlt">earthquake</span> source <span class="hlt">modelling</span> shrink towards common source-medium descriptions and a source near-field/far-field data point of view. We explore and facilitate the combination of InSAR-derived near-field static surface displacement maps and dynamic far-field seismological waveform data for global <span class="hlt">earthquake</span> source inferences. We join in the community efforts with the particular goal to improve crustal <span class="hlt">earthquake</span> source inferences in generally not well instrumented areas, where often only the global backbone observations of <span class="hlt">earthquakes</span> are available provided by seismological broadband sensor networks and, since recently, by Sentinel-1 SAR acquisitions. We present our work on <span class="hlt">modelling</span> standards for the combination of static and dynamic surface displacements in the source's near-field and far-field, e.g. on data and prediction error estimations as well as <span class="hlt">model</span> uncertainty estimation. Rectangular dislocations and moment-tensor point sources are exchanged by simple planar finite</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006PhRvC..73f5501L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006PhRvC..73f5501L"><span>Parity <span class="hlt">nonconservation</span> in elastic p→p scattering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, C.-P.; Hyun, C. H.; Desplanques, B.</p> <p>2006-06-01</p> <p>By looking at the parity-<span class="hlt">nonconserving</span> (PNC) asymmetries for different energies in p→p scattering, it is in principle possible to determine the PNC ρNN and ωNN couplings of a single-meson-exchange <span class="hlt">model</span> of the PNC NN force. Analysis of the experimental data at 13.6, 45, and 221 MeV was performed by Carlson , [Phys. Rev. C 65, 035502 (2002)] who concluded the data were in agreement with the uncertainties accorded the original DDH estimates for the PNC meson-nucleon couplings. In this work it is shown first that a comparison with updated hadronic predictions of these couplings suggests the existence of some discrepancy for the PNC ωNN coupling. The effect of varying the strong coupling constants and introducing cutoffs in the one-boson-exchange weak potential is then investigated. As expected, the resulting asymmetry is quite sensitive to these parameters regardless of the energy. However, the above mentioned discrepancy persists. The dependence of this conclusion on various ingredients entering an improved description of the PNC NN force is also examined. Additional mechanisms include the two-pion resonance nature of the rho meson and some momentum dependence of the isoscalar PNC ρNN vertex. None of these corrections removes or even alleviates the above discrepancy. Their impact on the theoretical determination of the vector meson-nucleon couplings, the description of the PNC force in terms of single-meson exchange, and the interpretation of measurements are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20974514','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20974514"><span>Breit interaction and parity <span class="hlt">nonconservation</span> in many-electron atoms</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Dzuba, V. A.; Flambaum, V. V.; Safronova, M. S.</p> <p>2006-02-15</p> <p>We present accurate ab initio nonperturbative calculations of the Breit correction to the parity <span class="hlt">nonconserving</span> (PNC) amplitudes of the 6s-7s and 6s-5d{sub 3/2} transitions in Cs, 7s-8s and 7s-6d{sub 3/2} transitions in Fr, 6s-5d{sub 3/2} transition in Ba{sup +}, 7s-6d{sub 3/2} transition in Ra{sup +}, and 6p{sub 1/2}-6p{sub 3}/{sub 2} transition in Tl. The results for the 6s-7s transition in Cs and 7s-8s transition in Fr are in good agreement with other calculations. We demonstrate that higher-orders many-body corrections to the Breit interaction are especially important for the s-d PNC amplitudes. We confirm good agreement of the PNC measurements for cesium and thallium with the standard <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11009414','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11009414"><span>A mechanical <span class="hlt">model</span> for intraplate <span class="hlt">earthquakes</span>: application to the new madrid seismic zone</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kenner; Segall</p> <p>2000-09-29</p> <p>We present a time-dependent <span class="hlt">model</span> for the generation of repeated intraplate <span class="hlt">earthquakes</span> that incorporates a weak lower crustal zone within an elastic lithosphere. Relaxation of this weak zone after tectonic perturbations transfers stress to the overlying crust, generating a sequence of <span class="hlt">earthquakes</span> that continues until the zone fully relaxes. Simulations predict large (5 to 10 meters) slip events with recurrence intervals of 250 to 4000 years and cumulative offsets of about 100 meters, depending on material parameters and far-field stress magnitude. Most are consistent with <span class="hlt">earthquake</span> magnitude, coseismic slip, recurrence intervals, cumulative offset, and surface deformation rates in the New Madrid Seismic Zone. Computed interseismic strain rates may not be detectable with available geodetic data, implying that low observed rates of strain accumulation cannot be used to rule out future damaging <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.2264L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.2264L"><span>Source <span class="hlt">models</span> of great <span class="hlt">earthquakes</span> from ultra low-frequency normal mode data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lentas, Konstantinos; Ferreira, Ana; Clévédé, Eric</p> <p>2014-05-01</p> <p>We present a new <span class="hlt">earthquake</span> source inversion technique based on normal mode data for the simultaneous determination of the rupture duration, length and moment tensor of large <span class="hlt">earthquakes</span> with unilateral rupture. We use ultra low-frequency (f < 1 mHz) normal mode spheroidal multiplets and the phases of split free oscillations, which are <span class="hlt">modelled</span> using Higher Order Perturbation Theory (HOPT), taking into account the Earth's rotation, ellipticity and lateral heterogeneities. A Monte Carlo exploration of the <span class="hlt">model</span> space is carried out, enabling the assessment of source parameter tradeoffs and uncertainties. We carry out synthetic tests for four different realistic artificial <span class="hlt">earthquakes</span> with different faulting mechanisms and magnitudes (Mw 8.1-9.3) to investigate errors in the source inversions due to: (i) unmodelled 3-D Earth structure; (ii) noise in the data; (iii) uncertainties in spatio-temporal <span class="hlt">earthquake</span> location; and, (iv) neglecting the source finiteness in point source moment tensor inversions. We find that unmodelled 3-D structure is the most serious source of errors for rupture duration and length determinations especially for the lowest magnitude artificial events. The errors in moment magnitude and fault mechanism are generally small, with the rake angle showing systematically larger errors (up to 20 degrees). We then carry out source inversions of five giant thrust <span class="hlt">earthquakes</span> (Mw ≥ 8.5): (i) the 26 December 2004 Sumatra-Andaman <span class="hlt">earthquake</span>; (ii) the 28 March 2005 Nias, Sumatra <span class="hlt">earthquake</span>; (iii) the 12 September 2007 Bengkulu <span class="hlt">earthquake</span>; (iv) the Tohoku, Japan <span class="hlt">earthquake</span> of 11 March 2011; (v) the Maule, Chile <span class="hlt">earthquake</span> of 27 February 2010; and (vi) the recent 24 May 2013 Mw 8.3 Okhotsk Sea, Russia, deep (607 km) <span class="hlt">earthquake</span>. While finite source inversions for rupture length, duration, magnitude and fault mechanism are possible for the Sumatra-Andaman and Tohoku events, for all the other events their lower magnitudes do not allow stable inversions of mode</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26282331','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26282331"><span>Cross-cultural comparisons between the <span class="hlt">earthquake</span> preparedness <span class="hlt">models</span> of Taiwan and New Zealand.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jang, Li-Ju; Wang, Jieh-Jiuh; Paton, Douglas; Tsai, Ning-Yu</p> <p>2016-04-01</p> <p>Taiwan and New Zealand are both located in the Pacific Rim where 81 per cent of the world's largest <span class="hlt">earthquakes</span> occur. Effective programmes for increasing people's preparedness for these hazards are essential. This paper tests the applicability of the community engagement theory of hazard preparedness in two distinct cultural contexts. Structural equation <span class="hlt">modelling</span> analysis provides support for this theory. The paper suggests that the close fit between theory and data that is achieved by excluding trust supports the theoretical prediction that familiarity with a hazard negates the need to trust external sources. The results demonstrate that the hazard preparedness theory is applicable to communities that have previously experienced <span class="hlt">earthquakes</span> and are therefore familiar with the associated hazards and the need for <span class="hlt">earthquake</span> preparedness. The paper also argues that cross-cultural comparisons provide opportunities for collaborative research and learning as well as access to a wider range of potential <span class="hlt">earthquake</span> risk management strategies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA529678','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA529678"><span>Transportations Systems <span class="hlt">Modeling</span> and Applications in <span class="hlt">Earthquake</span> Engineering</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-07-01</p> <p>Missouri State Emergency Management Agency), Mr. Richard Bennett (Missouri Department of Transportation), Mr. Phillip Anello (Illinois Emergency Management...sufficient demand during the post-<span class="hlt">earthquake</span> evacuation process , and the flows from different evacuation zones can be evacuated to any safe zones...assignment step of the conventional four-step transportation demand forecasting process (Weiner 1987). Traffic assignment methods (static or dynamic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1411715B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1411715B"><span>The investigation of blind continental <span class="hlt">earthquake</span> sources through analogue and numerical <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bonini, L.; Toscani, G.; Seno, S.</p> <p>2012-04-01</p> <p>One of the most challenging topic in <span class="hlt">earthquake</span> geology is to characterize the seismogenic sources, i.e. the potential causative faults of <span class="hlt">earthquakes</span>. The main seismogenic layer is located in the upper brittle crust. Nevertheless it does not mean that a fault take up the whole schizosphere: i.e. from the brittle-plastic transition to the surface. Indeed, latest damaging <span class="hlt">earthquakes</span> were generated by blind or "hidden" faults: 23 Oct. 2011, Van <span class="hlt">earthquake</span> (Mw 7.1, Turkey); 3 Sep 2010, Darfield <span class="hlt">earthquake</span> (Mw 7.1, New Zealand); 12 January 2010 Haiti <span class="hlt">earthquake</span> (Mw 7.0); 6 April 2009 L'Aquila <span class="hlt">earthquake</span> (Mw 6.3, Italy). Therefore understand how a fault grows and develops is a key question to evaluate the seismogenic potential of an area. Analogue <span class="hlt">model</span> was used to understand kinematics and geometry of the geological structures since the beginning of the modern geology. On the other hand, numerical <span class="hlt">model</span> develops much more during the last thirty years. Nowadays we can use these two methods working together providing mutual interactions. In the two-three most recent years we tried to use both numerical and analogue <span class="hlt">models</span> to investigate the long-term and short-term evolution of a blind normal fault. To do this we improved the Analogue <span class="hlt">Model</span> Laboratory of the University of Pavia with a laser scanner, a stepper motor and other high resolution tools in order to detect the distribution of the deformation mainly induced by blind faults. The goal of this kind of approach is to mimic the effects of the faults movements in a scaled <span class="hlt">model</span>. We selected two seismogenic source cases: the causative fault of the 1908 Messina <span class="hlt">earthquake</span> (Mw 7.1) and that of the 2009 L'Aquila <span class="hlt">earthquake</span> (Mw 6.3). In the first case we investigate the long term evolution of this structure using a set of analogue <span class="hlt">models</span> and afterwards a numerical <span class="hlt">model</span> of our sandbox allow us to investigate stress and strain partitioning. In the second case we performed only an analogue <span class="hlt">model</span> of short-term evolution of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S22D..04T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S22D..04T"><span>Locating and <span class="hlt">Modeling</span> Regional <span class="hlt">Earthquakes</span> with Broadband Waveform Data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tan, Y.; Zhu, L.; Helmberger, D.</p> <p>2003-12-01</p> <p>Retrieving source parameters of small <span class="hlt">earthquakes</span> (Mw < 4.5), including mechanism, depth, location and origin time, relies on local and regional seismic data. Although source characterization for such small events achieves a satisfactory stage in some places with a dense seismic network, such as TriNet, Southern California, a worthy revisit to the historical events in these places or an effective, real-time investigation of small events in many other places, where normally only a few local waveforms plus some short-period recordings are available, is still a problem. To address this issue, we introduce a new type of approach that estimates location, depth, origin time and fault parameters based on 3-component waveform matching in terms of separated Pnl, Rayleigh and Love waves. We show that most local waveforms can be well <span class="hlt">modeled</span> by a regionalized 1-D <span class="hlt">model</span> plus different timing corrections for Pnl, Rayleigh and Love waves at relatively long periods, i.e., 4-100 sec for Pnl, and 8-100 sec for surface waves, except for few anomalous paths involving greater structural complexity, meanwhile, these timing corrections reveal similar azimuthal patterns for well-located cluster events, despite their different focal mechanisms. Thus, we can calibrate the paths separately for Pnl, Rayleigh and Love waves with the timing corrections from well-determined events widely recorded by a dense modern seismic network or a temporary PASSCAL experiment. In return, we can locate events and extract their fault parameters by waveform matching for available waveform data, which could be as less as from two stations, assuming timing corrections from the calibration. The accuracy of the obtained source parameters is subject to the error carried by the events used for the calibration. The detailed method requires a Green­_s function library constructed from a regionalized 1-D <span class="hlt">model</span> together with necessary calibration information, and adopts a grid search strategy for both hypercenter and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011ESASP.696E...5B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011ESASP.696E...5B"><span><span class="hlt">Modelling</span> and Observing the 8.8 Chile and 9.0 Japan <span class="hlt">Earthquakes</span> Using GOCE</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Broerse, T.; Visser, P.; Bouman, J.; Fuchs, M.; Vermeersen, B.; Schmidt, M.</p> <p>2011-07-01</p> <p>Large <span class="hlt">earthquakes</span> do not only heavily deform the crust in the vicinity of the fault, they also change the gravity field of the area affected by the <span class="hlt">earthquake</span> due to mass redistribution in the upper layers of the Earth. Besides that, for sub-oceanic <span class="hlt">earthquakes</span> deformation of the ocean floor causes relative sea-level changes and mass redistribution of water that has again a significant effect on the gravity field. Such a sub-oceanic <span class="hlt">earthquake</span> occurred on 27 February 2010 in central Chili with a magnitude of Mw 8.8 and on 11 March 2011 with a magnitude of Mw 9.0 near the east coast of Honshu, Japan. This makes both a potential candidate for detecting the co-seismic gravity changes in the GOCE gradiometer data. We will assess the detectability of gravity field changes in the GOCE gravity gradients by <span class="hlt">modelling</span> these <span class="hlt">earthquakes</span> using a forward <span class="hlt">model</span> as well as taking differences of GOCE data before and after the respective <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70035883','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70035883"><span>PAGER-CAT: A composite <span class="hlt">earthquake</span> catalog for calibrating global fatality <span class="hlt">models</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>Allen, T.I.; Marano, K.D.; Earle, P.S.; Wald, D.J.</p> <p>2009-01-01</p> <p>We have described the compilation and contents of PAGER-CAT, an <span class="hlt">earthquake</span> catalog developed principally for calibrating <span class="hlt">earthquake</span> fatality <span class="hlt">models</span>. It brings together information from a range of sources in a comprehensive, easy to use digital format. <span class="hlt">Earthquake</span> source information (e.g., origin time, hypocenter, and magnitude) contained in PAGER-CAT has been used to develop an Atlas of Shake Maps of historical <span class="hlt">earthquakes</span> (Allen et al. 2008) that can subsequently be used to estimate the population exposed to various levels of ground shaking (Wald et al. 2008). These measures will ultimately yield improved <span class="hlt">earthquake</span> loss <span class="hlt">models</span> employing the uniform hazard mapping methods of ShakeMap. Currently PAGER-CAT does not consistently contain indicators of landslide and liquefaction occurrence prior to 1973. In future PAGER-CAT releases we plan to better document the incidence of these secondary hazards. This information is contained in some existing global catalogs but is far from complete and often difficult to parse. Landslide and liquefaction hazards can be important factors contributing to <span class="hlt">earthquake</span> losses (e.g., Marano et al. unpublished). Consequently, the absence of secondary hazard indicators in PAGER-CAT, particularly for events prior to 1973, could be misleading to sorne users concerned with ground-shaking-related losses. We have applied our best judgment in the selection of PAGER-CAT's preferred source parameters and <span class="hlt">earthquake</span> effects. We acknowledge the creation of a composite catalog always requires subjective decisions, but we believe PAGER-CAT represents a significant step forward in bringing together the best available estimates of <span class="hlt">earthquake</span> source parameters and reports of <span class="hlt">earthquake</span> effects. All information considered in PAGER-CAT is stored as provided in its native catalog so that other users can modify PAGER preferred parameters based on their specific needs or opinions. As with all catalogs, the values of some parameters listed in PAGER-CAT are</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMNG44A..07T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMNG44A..07T"><span>Damage and the Gutenberg-Richter Law: from simple <span class="hlt">models</span> to natural <span class="hlt">earthquake</span> fault systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tiampo, K. F.; Klein, W.; Rundle, J. B.; Dominguez, R.; Serino, C.</p> <p>2010-12-01</p> <p>Natural <span class="hlt">earthquake</span> fault systems are highly nonhomogeneous in space, where these inhomogeneities occur because the earth is made of a variety of materials which hold and dissipate stress differently. One way that the inhomogeneous nature of fault systems manifests itself is in the spatial patterns which emerge in seismicity graphs (Tiampo et al., 2002, 2007). Despite their inhomogeneous nature, real faults are often <span class="hlt">modeled</span> as spatially homogeneous systems. One argument for this approach is that <span class="hlt">earthquake</span> faults experience long range stress transfer, and if this range is longer than the length scales associated with the inhomogeneities of the system, the dynamics of the system may be unaffected by their presence. However, it is not clear that this is the case. In this work we study the scaling of an <span class="hlt">earthquake</span> <span class="hlt">model</span> that is a variation of the Olami-Feder-Christensen (OFC) <span class="hlt">model</span>, in order to explore the effect of spatial inhomogeneities on <span class="hlt">earthquake</span>-like systems when interaction ranges are long, but not necessarily longer than the distances associated with those inhomogeneities (Rundle and Jackson, 1977; Olami et al., 1988). For long ranges and without inhomogeneities, such <span class="hlt">models</span> have been found to produce scaling similar to GR scaling found in real <span class="hlt">earthquake</span> systems (Rundle and Klein, 1993). In the <span class="hlt">earthquake</span> <span class="hlt">models</span> discussed here, damage is distributed inhomogeneously throughout and the interaction ranges, while long, are not longer than all of the damage length scales. We find that the scaling depends not only on the amount of damage, but also on the spatial distribution of that damage. In addition, we study the behaviour of particular natural <span class="hlt">earthquake</span> faults and the spatial and temporal variation of GR scaling in those systems, in order to compare them with various damage cases from the simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH41B1706L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH41B1706L"><span><span class="hlt">Modeling</span> Tsunamis and Hydroacoustic Waves from Megathrust <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>Lotto, G. C.; Belair, G. M.; Kozdon, J. E.; Dunham, E. M.</p> <p>2013-12-01</p> <p>The immense damage caused by the 11 March 2011 Tohoku, Japan <span class="hlt">earthquake</span> demonstrated the importance of understanding tsunami excitation by megathrust ruptures. Of particular interest are any faster-propagating seismic or hydroacoustic signals that could be used to rapidly predict tsunami wave heights. To study the full seismic, acoustic, and tsunami wavefields, we have developed a provably stable and accurate finite-difference method that couples an elastic solid to a compressible fluid subject to gravitational restoring forces. We introduce a new treatment of the dynamic (free surface) boundary condition on the moving sea surface in the presence of gravity that is valid for small-amplitude perturbations about an ocean initially in hydrostatic balance. This permits us to <span class="hlt">model</span> surface gravity waves in the linearized limit, including dispersion from nonhydrostatic motions at short wavelengths. This is done using summation-by-parts (SBP) finite difference operators and weak enforcement of boundary conditions. Shallow coseismic slip during megathrust events causes seafloor uplift that excites both tsunamis and long-period (~10 s) hydroacoustic waves; the latter ocean sound waves travel at several km/s and reach the coast many minutes sooner than tsunami waves. These hydroacoustic waves might be used as part of local tsunami early warning systems. Our previous dynamic rupture simulations of the Tohoku event, which neglected surface gravity waves, revealed correlations between pressure perturbations recorded at the seafloor (associated with ~10 s hydroacoustic waves in the ocean) and near-trench seafloor uplift caused by shallow slip. Now that we can <span class="hlt">model</span> tsunamis within the same code, we plan to quantify the correlation between these pressure perturbations and tsunami height. We are also investigating properties of these hydroacoustic modes, which involve significant motions of the solid Earth as well as the ocean. Phase and group velocity curves for a uniform ocean</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20630420','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20630420"><span>Bounded solutions for <span class="hlt">nonconserving</span>-parity pseudoscalar potentials</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Castro, Antonio S. de; Malheiro, Manuel; Lisboa, Ronai</p> <p>2004-12-02</p> <p>The Dirac equation is analyzed for <span class="hlt">nonconserving</span>-parity pseudoscalar radial potentials in 3+1 dimensions. It is shown that despite the <span class="hlt">nonconservation</span> of parity this general problem can be reduced to a Sturm-Liouville problem of nonrelativistic fermions in spherically symmetric effective potentials. The searching for bounded solutions is done for the power-law and Yukawa potentials. The use of the methodology of effective potentials allow us to conclude that the existence of bound-state solutions depends whether the potential leads to a definite effective potential-well structure or to an effective potential less singular than -1/4r2.</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('http://adsabs.harvard.edu/abs/2013AGUFM.T11D2496H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T11D2496H"><span>Post <span class="hlt">Earthquake</span> Investigation Of The Mw7.8 Haida Gwaii, Canada, Rupture Area And Constraints On <span class="hlt">Earthquake</span> Source <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Haeussler, P. J.; Witter, R. C.; Wang, K.</p> <p>2013-12-01</p> <p>The October 28, 2012 Mw 7.8 Haida Gwaii, British Columbia, <span class="hlt">earthquake</span> was the second largest historical <span class="hlt">earthquake</span> recorded in Canada. <span class="hlt">Earthquake</span> seismology and GPS geodesy shows this was an underthrusting event, in agreement with prior studies that indicated oblique underthrusting of the Haida Gwaii by the Pacific plate. Coseismic deformation is poorly constrained by geodesy, with only six GPS sites and two tide gauge stations anywhere near the rupture area. In order to better constrain the coseismic deformation, we measured the upper limit of sessile intertidal organisms at 26 sites relative to sea level. We dominantly measured the positions of bladder weed (fucus distichus - 617 observations) and the common acorn barnacle (Balanus balanoides - 686 observations). Physical conditions control the upper limit of sessile intertidal organisms, so we tried to find the quietest water conditions, with steep, but not overhanging faces, where slosh from wave motion was minimized. We focused on the western side of the islands as rupture <span class="hlt">models</span> indicated that the greatest displacement was there. However, we were also looking for calm water sites in bays located as close as possible to the often tumultuous Pacific Ocean. In addition, we made 322 measurements of sea level that will be used to develop a precise tidal <span class="hlt">model</span> and to evaluate the position of the organisms with respect to a common sea level datum. We anticipate the resolution of the method will be about 20-30 cm. The sites were focused on the western side of the Haida Gwaii from Wells Bay on the south up to Otard Bay to the north, with 5 transects across strike. We also collected data at the town of Masset, which lies outside of the deformation zone of the <span class="hlt">earthquake</span>. We observed dried and desiccated bands of fucus and barnacles at two sites on the western coast of southern Moresby Island (Gowgia Bay and Wells Bay). Gowgia Bay had the strongest evidence of uplift with fucus that was dried out and apparently dead. A</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T22C..03W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T22C..03W"><span><span class="hlt">Modeling</span> Long-term Changes of Low-frequency <span class="hlt">Earthquake</span> Recurrence</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>2015-12-01</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 recurrence 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 recurrence are still under debate. In this study, we combine observations of long-term changes in LFE recurrence near Parkfield, California (Wu et al. 2013) with a brittle and ductile friction (BDF) <span class="hlt">model</span> (Daub et al. 2011), and use the <span class="hlt">model</span> to constrain the possible physical mechanisms causing the observed long-term changes in LFE recurrence after the 2004 M6 Parkfield <span class="hlt">earthquake</span>. The BDF <span class="hlt">model</span> mimics the slipping of deep fault patches by a spring-drugged block slider with both brittle and ductile friction components. Our on-going work includes testing the BDF <span class="hlt">model</span> by varying two sets of parameters: 1) time varying shear stress caused by the postseismic relaxation of the static stress imposed by the 2004 Parkfield <span class="hlt">earthquake</span>, and 2) gradual recovery of brittle friction strength following the strong shaking of the Parkfield <span class="hlt">earthquake</span>. Hopefully our <span class="hlt">modeling</span> results can help to clarify the roles of the two mechanisms, and link seismic observations of LFE to the physics of deep fault deformation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013GeoJI.192..710B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013GeoJI.192..710B"><span>Location and magnitudes of <span class="hlt">earthquakes</span> in Central Asia from seismic intensity data: <span class="hlt">model</span> calibration and validation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bindi, Dino; Capera, Augusto A. Gómez; Parolai, Stefano; Abdrakhmatov, Kanatbek; Stucchi, Massimiliano; Zschau, Jochen</p> <p>2013-02-01</p> <p>In this study, we estimate the location and magnitude of Central Asian <span class="hlt">earthquake</span> from macroseismic intensity data. A set of 2373 intensity observations from 15 <span class="hlt">earthquakes</span> is analysed to calibrate non-parametric <span class="hlt">models</span> for the source and attenuation with distance, the distance being computed from the instrumental epicentres located according to the International Seismological Centre (ISC) catalogue. In a second step, the non-parametric source <span class="hlt">model</span> is regressed against different magnitude values (e.g. MLH, mb, MS, Mw) as listed in various instrumental catalogues. The reliability of the calibrated <span class="hlt">model</span> is then assessed by applying the methodology to macroseismic intensity data from 29 validation <span class="hlt">earthquakes</span> for which both MLH and mb are available from the Central Asian Seismic Risk Initiative (CASRI) project and the ISC catalogue. An overall agreement is found for both the location and magnitude of these events, with the distribution of the differences between instrumental and intensity-based magnitudes having almost a zero mean, and standard deviations equal to 0.30 and 0.44 for mb and MLH, respectively. The largest discrepancies are observed for the location of the 1985, MLH = 7.0 southern Xinjiang <span class="hlt">earthquake</span>, whose location is outside the area covered by the intensity assignments, and for the magnitude of the 1974, mb = 6.2 Markansu <span class="hlt">earthquake</span>, which shows a difference in magnitude greater than one unit in terms of MLH. Finally, the relationships calibrated for the non-parametric source <span class="hlt">model</span> are applied to assign different magnitude-scale values to <span class="hlt">earthquakes</span> that lack instrumental information. In particular, an intensity-based moment magnitude is assigned to all of the validation <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSeis..21.1001A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSeis..21.1001A"><span>Empirical <span class="hlt">models</span> for the prediction of ground motion duration for intraplate <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>Anbazhagan, P.; Neaz Sheikh, M.; Bajaj, Ketan; Mariya Dayana, P. J.; Madhura, H.; Reddy, G. R.</p> <p>2017-07-01</p> <p>Many empirical relationships for the <span class="hlt">earthquake</span> ground motion duration were developed for interplate region, whereas only a very limited number of empirical relationships exist for intraplate region. Also, the existing relationships were developed based mostly on the scaled recorded interplate <span class="hlt">earthquakes</span> to represent intraplate <span class="hlt">earthquakes</span>. To the author's knowledge, none of the existing relationships for the intraplate regions were developed using only the data from intraplate regions. Therefore, an attempt is made in this study to develop empirical predictive relationships of <span class="hlt">earthquake</span> ground motion duration (i.e., significant and bracketed) with <span class="hlt">earthquake</span> magnitude, hypocentral distance, and site conditions (i.e., rock and soil sites) using the data compiled from intraplate regions of Canada, Australia, Peninsular India, and the central and southern parts of the USA. The compiled <span class="hlt">earthquake</span> ground motion data consists of 600 records with moment magnitudes ranging from 3.0 to 6.5 and hypocentral distances ranging from 4 to 1000 km. The non-linear mixed-effect (NLMEs) and logistic regression techniques (to account for zero duration) were used to fit predictive <span class="hlt">models</span> to the duration data. The bracketed duration was found to be decreased with an increase in the hypocentral distance and increased with an increase in the magnitude of the <span class="hlt">earthquake</span>. The significant duration was found to be increased with the increase in the magnitude and hypocentral distance of the <span class="hlt">earthquake</span>. Both significant and bracketed durations were predicted higher in rock sites than in soil sites. The predictive relationships developed herein are compared with the existing relationships for interplate and intraplate regions. The developed relationship for bracketed duration predicts lower durations for rock and soil sites. However, the developed relationship for a significant duration predicts lower durations up to a certain distance and thereafter predicts higher durations compared to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSeis.tmp...15A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSeis.tmp...15A"><span>Empirical <span class="hlt">models</span> for the prediction of ground motion duration for intraplate <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>Anbazhagan, P.; Neaz Sheikh, M.; Bajaj, Ketan; Mariya Dayana, P. J.; Madhura, H.; Reddy, G. R.</p> <p>2017-02-01</p> <p>Many empirical relationships for the <span class="hlt">earthquake</span> ground motion duration were developed for interplate region, whereas only a very limited number of empirical relationships exist for intraplate region. Also, the existing relationships were developed based mostly on the scaled recorded interplate <span class="hlt">earthquakes</span> to represent intraplate <span class="hlt">earthquakes</span>. To the author's knowledge, none of the existing relationships for the intraplate regions were developed using only the data from intraplate regions. Therefore, an attempt is made in this study to develop empirical predictive relationships of <span class="hlt">earthquake</span> ground motion duration (i.e., significant and bracketed) with <span class="hlt">earthquake</span> magnitude, hypocentral distance, and site conditions (i.e., rock and soil sites) using the data compiled from intraplate regions of Canada, Australia, Peninsular India, and the central and southern parts of the USA. The compiled <span class="hlt">earthquake</span> ground motion data consists of 600 records with moment magnitudes ranging from 3.0 to 6.5 and hypocentral distances ranging from 4 to 1000 km. The non-linear mixed-effect (NLMEs) and logistic regression techniques (to account for zero duration) were used to fit predictive <span class="hlt">models</span> to the duration data. The bracketed duration was found to be decreased with an increase in the hypocentral distance and increased with an increase in the magnitude of the <span class="hlt">earthquake</span>. The significant duration was found to be increased with the increase in the magnitude and hypocentral distance of the <span class="hlt">earthquake</span>. Both significant and bracketed durations were predicted higher in rock sites than in soil sites. The predictive relationships developed herein are compared with the existing relationships for interplate and intraplate regions. The developed relationship for bracketed duration predicts lower durations for rock and soil sites. However, the developed relationship for a significant duration predicts lower durations up to a certain distance and thereafter predicts higher durations compared to the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3364293','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3364293"><span><span class="hlt">Modelling</span> Psychological Responses to the Great East Japan <span class="hlt">Earthquake</span> and Nuclear Incident</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Goodwin, Robin; Takahashi, Masahito; Sun, Shaojing; Gaines, Stanley O.</p> <p>2012-01-01</p> <p>The Great East Japan (Tōhoku/Kanto) <span class="hlt">earthquake</span> of March 2011was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have <span class="hlt">modelled</span> individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan <span class="hlt">earthquake</span> and nuclear incident, with data collected 11–13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the <span class="hlt">earthquake</span> and leaking nuclear plants), Tokyo/Chiba (approximately 220 km from the nuclear plants), and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants). Results indicated significant regional differences in risk perception, with greater concern over <span class="hlt">earthquake</span> risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about <span class="hlt">earthquake</span> and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived <span class="hlt">earthquake</span> and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan). The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events. PMID:22666380</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/10184921','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/10184921"><span>An exact renormalization <span class="hlt">model</span> for <span class="hlt">earthquakes</span> and material failure: Statics and dynamics</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Newman, W.I. |; Gabrielov, A.M. |; Durand, T.A.; Phoenix, S.L.; Turcotte, D.L.</p> <p>1993-09-12</p> <p><span class="hlt">Earthquake</span> events are well-known to prams a variety of empirical scaling laws. Accordingly, renormalization methods offer some hope for understanding why <span class="hlt">earthquake</span> statistics behave in a similar way over orders of magnitude of energy. We review the progress made in the use of renormalization methods in approaching the <span class="hlt">earthquake</span> problem. In particular, <span class="hlt">earthquake</span> events have been <span class="hlt">modeled</span> by previous investigators as hierarchically organized bundles of fibers with equal load sharing. We consider by computational and analytic means the failure properties of such bundles of fibers, a problem that may be treated exactly by renormalization methods. We show, independent of the specific properties of an individual fiber, that the stress and time thresholds for failure of fiber bundles obey universal, albeit different, staling laws with respect to the size of the bundles. The application of these results to fracture processes in <span class="hlt">earthquake</span> events and in engineering materials helps to provide insight into some of the observed patterns and scaling-in particular, the apparent weakening of <span class="hlt">earthquake</span> faults and composite materials with respect to size, and the apparent emergence of relatively well-defined stresses and times when failure is seemingly assured.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010JESS..119..553A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010JESS..119..553A"><span>The 2007 Bengkulu <span class="hlt">earthquake</span>, its rupture <span class="hlt">model</span> and implications for seismic hazard</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ambikapathy, A.; Catherine, J. K.; Gahalaut, V. K.; Narsaiah, M.; Bansal, A.; Mahesh, P.</p> <p>2010-08-01</p> <p>The 12 September 2007 great Bengkulu <span class="hlt">earthquake</span> ( M w 8.4) occurred on the west coast of Sumatra about 130 km SW of Bengkulu. The <span class="hlt">earthquake</span> was followed by two strong aftershocks of M w 7.9 and 7.0. We estimate coseismic offsets due to the mainshock, derived from near-field Global Positioning System (GPS) measurements from nine continuous SuGAr sites operated by the California Institute of Technology (Caltech) group. Using a forward <span class="hlt">modelling</span> approach, we estimated slip distribution on the causative rupture of the 2007 Bengkulu <span class="hlt">earthquake</span> and found two patches of large slip, one located north of the mainshock epicenter and the other, under the Pagai Islands. Both patches of large slip on the rupture occurred under the island belt and shallow water. Thus, despite its great magnitude, this <span class="hlt">earthquake</span> did not generate a major tsunami. Further, we suggest that the occurrence of great <span class="hlt">earthquakes</span> in the subduction zone on either side of the Siberut Island region, might have led to the increase in static stress in the region, where the last great <span class="hlt">earthquake</span> occurred in 1797 and where there is evidence of strain accumulation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PApGe.168..495N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PApGe.168..495N"><span><span class="hlt">Modeling</span> of Ground Motion at Napoli for the 1688 Scenario <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>Nunziata, C.; Sacco, C.; Panza, G. F.</p> <p>2011-03-01</p> <p>The Sannio seismogenic area turns out to be responsible for the highest peak ground accelerations (PGA) and seismic response spectra (SRS) at Napoli. The 1688 <span class="hlt">earthquake</span> is considered representative of the area, and realistic synthetic seismograms have been computed for this scenario <span class="hlt">earthquake</span> at the historical center and the eastern sector of Napoli. The use of a hybrid technique based on mode summation and finite-difference methods is fully justified by the available detailed knowledge about the geological and geophysical properties of the Neapolitan subsoil. This <span class="hlt">modeling</span> makes it possible to recognize that amplifications of ~2 for PGA and >3 for SRS are to be expected because of the pyroclastic soil cover. Based on the information contained in the available catalogs, different magnitudes have been considered. Taking into account the correlation, valid for the Italian territory, between synthetic PGA and observed intensities, it turns out that the most probable magnitude ( M) of the 1688 <span class="hlt">earthquake</span> is 6.7, while M = 7.3 should be assigned to a conservative scenario <span class="hlt">earthquake</span>. Comparison of the computed response spectra for the 1688 scenario <span class="hlt">earthquake</span> with the Italian seismic building code shows that the code is adequate with respect to the expected effects at the historical center of Napoli, but that it underestimates the possible ground motion at the eastern sector, in particular at the newly developed area built after the 1980 <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22666380','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22666380"><span><span class="hlt">Modelling</span> psychological responses to the Great East Japan <span class="hlt">earthquake</span> and nuclear incident.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Goodwin, Robin; Takahashi, Masahito; Sun, Shaojing; Gaines, Stanley O</p> <p>2012-01-01</p> <p>The Great East Japan (Tōhoku/Kanto) <span class="hlt">earthquake</span> of March 2011 was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have <span class="hlt">modelled</span> individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan <span class="hlt">earthquake</span> and nuclear incident, with data collected 11-13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the <span class="hlt">earthquake</span> and leaking nuclear plants), Tokyo/Chiba (approximately 220 km from the nuclear plants), and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants). Results indicated significant regional differences in risk perception, with greater concern over <span class="hlt">earthquake</span> risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about <span class="hlt">earthquake</span> and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived <span class="hlt">earthquake</span> and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan). The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.7960S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.7960S"><span>Effect of data quality on a hybrid Coulomb/STEP <span class="hlt">model</span> for <span class="hlt">earthquake</span> forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Steacy, Sandy; Jimenez, Abigail; Gerstenberger, Matt; Christophersen, Annemarie</p> <p>2014-05-01</p> <p>Operational <span class="hlt">earthquake</span> forecasting is rapidly becoming a 'hot topic' as civil protection authorities seek quantitative information on likely near future <span class="hlt">earthquake</span> distributions during seismic crises. At present, most of the <span class="hlt">models</span> in public domain are statistical and use information about past and present seismicity as well as b-value and Omori's law to forecast future rates. A limited number of researchers, however, are developing hybrid <span class="hlt">models</span> which add spatial constraints from Coulomb stress <span class="hlt">modeling</span> to existing statistical approaches. Steacy et al. (2013), for instance, recently tested a <span class="hlt">model</span> that combines Coulomb stress patterns with the STEP (short-term <span class="hlt">earthquake</span> probability) approach against seismicity observed during the 2010-2012 Canterbury <span class="hlt">earthquake</span> sequence. They found that the new <span class="hlt">model</span> performed at least as well as, and often better than, STEP when tested against retrospective data but that STEP was generally better in pseudo-prospective tests that involved data actually available within the first 10 days of each event of interest. They suggested that the major reason for this discrepancy was uncertainty in the slip <span class="hlt">models</span> and, in particular, in the geometries of the faults involved in each complex major event. Here we test this hypothesis by developing a number of retrospective forecasts for the Landers <span class="hlt">earthquake</span> using hypothetical slip distributions developed by Steacy et al. (2004) to investigate the sensitivity of Coulomb stress <span class="hlt">models</span> to fault geometry and <span class="hlt">earthquake</span> slip. Specifically, we consider slip <span class="hlt">models</span> based on the NEIC location, the CMT solution, surface rupture, and published inversions and find significant variation in the relative performance of the <span class="hlt">models</span> depending upon the input data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6103729','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6103729"><span>Locating <span class="hlt">earthquakes</span> in west Texas oil fields using 3-D anisotropic velocity <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hua, Fa; Doser, D.; Baker, M. . Dept. of Geological Sciences)</p> <p>1993-02-01</p> <p><span class="hlt">Earthquakes</span> within the War-Wink gas field, Ward County, Texas, that have been located with a 1-D velocity <span class="hlt">model</span> occur near the edges and top of a naturally occurring overpressured zone. Because the War-Wink field is a structurally controlled anticline with significant velocity anisotropy associated with the overpressured zone and finely layered evaporites, the authors have attempted to re-locate <span class="hlt">earthquakes</span> using a 3-D anisotropic velocity <span class="hlt">model</span>. Preliminary results with this <span class="hlt">model</span> give the unsatisfactory result that many <span class="hlt">earthquakes</span> previously located at the top of the overpressured zone (3-3.5 km) moved into the evaporites (1-1.5 km) above the field. They believe that this result could be caused by: (1) aliasing the velocity <span class="hlt">model</span>; or (2) problems in determining the correct location minima when several minima exist. They are currently attempting to determine which of these causes is more likely for the unsatisfactory result observed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S31B2742G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S31B2742G"><span>Source mechanism inversion and ground motion <span class="hlt">modeling</span> of induced <span class="hlt">earthquakes</span> in Kuwait - A Bayesian approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gu, C.; Toksoz, M. N.; Marzouk, Y.; Al-Enezi, A.; Al-Jeri, F.; Buyukozturk, O.</p> <p>2016-12-01</p> <p>The increasing seismic activity in the regions of oil/gas fields due to fluid injection/extraction and hydraulic fracturing has drawn new attention in both academia and industry. Source mechanism and triggering stress of these induced <span class="hlt">earthquakes</span> are of great importance for understanding the physics of the seismic processes in reservoirs, and predicting ground motion in the vicinity of oil/gas fields. The induced seismicity data in our study are from Kuwait National Seismic Network (KNSN). Historically, Kuwait has low local seismicity; however, in recent years the KNSN has monitored more and more local <span class="hlt">earthquakes</span>. Since 1997, the KNSN has recorded more than 1000 <span class="hlt">earthquakes</span> (Mw < 5). In 2015, two local <span class="hlt">earthquakes</span> - Mw4.5 in 03/21/2015 and Mw4.1 in 08/18/2015 - have been recorded by both the Incorporated Research Institutions for Seismology (IRIS) and KNSN, and widely felt by people in Kuwait. These <span class="hlt">earthquakes</span> happen repeatedly in the same locations close to the oil/gas fields in Kuwait (see the uploaded image). The <span class="hlt">earthquakes</span> are generally small (Mw < 5) and are shallow with focal depths of about 2 to 4 km. Such events are very common in oil/gas reservoirs all over the world, including North America, Europe, and the Middle East. We determined the location and source mechanism of these local <span class="hlt">earthquakes</span>, with the uncertainties, using a Bayesian inversion method. The triggering stress of these <span class="hlt">earthquakes</span> was calculated based on the source mechanisms results. In addition, we <span class="hlt">modeled</span> the ground motion in Kuwait due to these local <span class="hlt">earthquakes</span>. Our results show that most likely these local <span class="hlt">earthquakes</span> occurred on pre-existing faults and were triggered by oil field activities. These events are generally smaller than Mw 5; however, these events, occurring in the reservoirs, are very shallow with focal depths less than about 4 km. As a result, in Kuwait, where oil fields are close to populated areas, these induced <span class="hlt">earthquakes</span> could produce ground accelerations high</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT........71R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT........71R"><span>Combining Dynamic <span class="hlt">Earthquake</span> and Tsunami <span class="hlt">Models</span> With Case Studies Offshore Alaska and Southern California</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ryan, Kenny</p> <p></p> <p><span class="hlt">Earthquakes</span> and their corresponding tsunamis pose significant hazard to popu- lated regions around the world. Therefore, it is critically important that we seek to more fully understand the physics of the combined <span class="hlt">earthquake</span>-tsunami system. One way to address this goal is through numerical <span class="hlt">modeling</span>. The work discussed herein focuses on combining dynamic <span class="hlt">earthquake</span> and tsunami <span class="hlt">models</span> through the use of the Finite Element Method (FEM) and the Finite Difference Method (FDM). Dynamic <span class="hlt">earthquake</span> <span class="hlt">models</span> ac- count for the force that the entire fault system exerts on each individual element of the <span class="hlt">model</span> for each time step, so that <span class="hlt">earthquake</span> rupture takes a path based on the physics of the <span class="hlt">model</span>; dynamic tsunami <span class="hlt">models</span> can incorporate water height variations to produce water wave formation, propagation, and inundation. Chapter 1 provides an introduction to some important concepts and equations of elastodynamics and fluid dynamics as well as a brief example of the FEM. In Chapter 2, we investigate the 3-D effects of realistic fault dynamics on slip, free surface deformation, and resulting tsunami formation from an Mw 9 megathrust <span class="hlt">earthquake</span> offshore Southern Alaska. Corresponding tsunami <span class="hlt">models</span>, which use a FDM to solve linear long-wave equations, match sea floor deformation, in time, to the free surface deformation from the rupture simulations. Tsunamis generated in this region could have large adverse effects on Pacific coasts. In Chapter 3, we construct a 3-D dynamic rupture <span class="hlt">model</span> of an <span class="hlt">earthquake</span> on a reverse fault structure offshore Southern California to <span class="hlt">model</span> the resulting tsunami, with a goal of elucidating the seismic and tsunami hazard in this area. The corresponding tsunami <span class="hlt">model</span> uses final seafloor displacements from the rupture <span class="hlt">model</span> as initial conditions to compute local propagation and inundation, resulting in large peak tsunami amplitudes northward and eastward due to site and path effects. In Chapter 4, we begin to evaluate 2-D <span class="hlt">earthquake</span> source parameters</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.205..509R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.205..509R"><span><span class="hlt">Earthquake</span> potential and magnitude limits inferred from a geodetic strain-rate <span class="hlt">model</span> for southern Europe</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.; Bird, P.; Jackson, D. D.</p> <p>2016-04-01</p> <p>The project Seismic Hazard Harmonization in Europe (SHARE), completed in 2013, presents significant improvements over previous regional seismic hazard <span class="hlt">modeling</span> efforts. The Global Strain Rate Map v2.1, sponsored by the Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> Foundation and built on a large set of self-consistent geodetic GPS velocities, was released in 2014. To check the SHARE seismic source <span class="hlt">models</span> that were based mainly on historical <span class="hlt">earthquakes</span> and active fault data, we first evaluate the SHARE historical <span class="hlt">earthquake</span> catalogues and demonstrate that the <span class="hlt">earthquake</span> magnitudes are acceptable. Then, we construct an <span class="hlt">earthquake</span> potential <span class="hlt">model</span> using the Global Strain Rate Map data. SHARE <span class="hlt">models</span> provided parameters from which magnitude-frequency distributions can be specified for each of 437 seismic source zones covering most of Europe. Because we are interested in proposed magnitude limits, and the original zones had insufficient data for accurate estimates, we combine zones into five groups according to SHARE's estimates of maximum magnitude. Using the strain rates, we calculate tectonic moment rates for each group. Next, we infer seismicity rates from the tectonic moment rates and compare them with historical and SHARE seismicity rates. For two of the groups, the tectonic moment rates are higher than the seismic moment rates of the SHARE <span class="hlt">models</span>. Consequently, the rates of large <span class="hlt">earthquakes</span> forecast by the SHARE <span class="hlt">models</span> are lower than those inferred from tectonic moment rate. In fact, the SHARE <span class="hlt">models</span> forecast higher seismicity rates than the historical rates, which indicate that the authors of SHARE were aware of the potentially higher seismic activities in the zones. For one group, the tectonic moment rate is lower than the seismic moment rates forecast by the SHARE <span class="hlt">models</span>. As a result, the rates of large <span class="hlt">earthquakes</span> in that group forecast by the SHARE <span class="hlt">model</span> are higher than those inferred from tectonic moment rate, but lower than what the historical data show. For the other two</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.1181A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.1181A"><span><span class="hlt">Earthquake</span> Hazard and Risk in Sub-Saharan Africa: current status of the Global <span class="hlt">Earthquake</span> <span class="hlt">model</span> (GEM) initiative in the region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ayele, Atalay; Midzi, Vunganai; Ateba, Bekoa; Mulabisana, Thifhelimbilu; Marimira, Kwangwari; Hlatywayo, Dumisani J.; Akpan, Ofonime; Amponsah, Paulina; Georges, Tuluka M.; Durrheim, Ray</p> <p>2013-04-01</p> <p>Large magnitude <span class="hlt">earthquakes</span> have been observed in Sub-Saharan Africa in the recent past, such as the Machaze event of 2006 (Mw, 7.0) in Mozambique and the 2009 Karonga <span class="hlt">earthquake</span> (Mw 6.2) in Malawi. The December 13, 1910 <span class="hlt">earthquake</span> (Ms = 7.3) in the Rukwa rift (Tanzania) is the largest of all instrumentally recorded events known to have occurred in East Africa. The overall <span class="hlt">earthquake</span> hazard in the region is on the lower side compared to other <span class="hlt">earthquake</span> prone areas in the globe. However, the risk level is high enough for it to receive attention of the African governments and the donor community. The latest <span class="hlt">earthquake</span> hazard map for the sub-Saharan Africa was done in 1999 and updating is long overdue as several development activities in the construction industry is booming allover sub-Saharan Africa. To this effect, regional seismologists are working together under the GEM (Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span>) framework to improve incomplete, inhomogeneous and uncertain catalogues. The working group is also contributing to the UNESCO-IGCP (SIDA) 601 project and assessing all possible sources of data for the catalogue as well as for the seismotectonic characteristics that will help to develop a reasonable hazard <span class="hlt">model</span> in the region. In the current progress, it is noted that the region is more seismically active than we thought. This demands the coordinated effort of the regional experts to systematically compile all available information for a better output so as to mitigate <span class="hlt">earthquake</span> risk in the sub-Saharan Africa.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT........76W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT........76W"><span>Statistical Mechanics of Colloidal Particles in <span class="hlt">Non-Conservative</span> Force Fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wakil Moyses, Henrique</p> <p></p> <p>Systems that are in mechanical equilibrium but are driven away from thermodynamic equilibrium present directed motion when in a thermal bath. This thesis explores this motion when systems are out of thermodynamic equilibrium due to the presence of <span class="hlt">non-conservative</span> force fields. The first system we explored are Brownian vortexes. These are stochastic machines that use static <span class="hlt">non-conservative</span> force fields to bias random thermal fluctuations into steadily circulating currents. The archetype for this class of systems is a colloidal sphere in an optical tweezer. Trapped near the focus of a strongly converging beam of light, the particle is displaced by random thermal kicks into the <span class="hlt">nonconservative</span> part of the optical force field arising from radiation pressure, which then biases its diffusion. Assuming the particle remains localized within the trap, its time-averaged trajectory traces out a toroidal vortex. Unlike trivial Brownian vortexes, such as the biased Brownian pendulum, which circulate preferentially in the direction of the bias, the general Brownian vortex can change direction and even topology in response to temperature changes. In this thesis we introduce a theory based on a perturbative expansion of the Fokker-Planck equation for weak <span class="hlt">non-conservative</span> driving. We show that the first-order solution takes the form of a modified Boltzmann relation and accounts for the rich phenomenology observed in experiments on micrometer-scale colloidal spheres in optical tweezers. Another system we explore are colloidal Janus particles composed of an optically absorbing and transparent faces. When illuminated by a defocused optical tweezer these particles swim vigorously, without requiring any chemical fuel. Most surprisingly, these optically activated colloidal swimmers circulate back and forth through the beam of light, tracing out regular sinuous patterns. In this thesis we propose a <span class="hlt">model</span> for this class of light-activated swimmers in which a combination of radiation</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFMPA33A1027R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFMPA33A1027R"><span>EQRM: An open-source event-based <span class="hlt">earthquake</span> risk <span class="hlt">modeling</span> program</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robinson, D. J.; Dhu, T.; Row, P.</p> <p>2007-12-01</p> <p>Geoscience Australia's <span class="hlt">Earthquake</span> Risk <span class="hlt">Model</span> (EQRM) is an event-based tool for <span class="hlt">earthquake</span> scenario ground motion and scenario loss <span class="hlt">modeling</span> as well as probabilistic seismic hazard (PSHA) and risk (PSRA) <span class="hlt">modeling</span>. It has been used to conduct PSHA and PSRA for many of Australia's largest cities and it has become an important tool for the emergency management community which use it for scneario response planning. It has the potential to link with <span class="hlt">earthquake</span> monitoring programs to provide automatic loss estimates from network recorded events. An open-source alpha-release version of the software is freely available on SourceForge. It can be used for hazard or risk analyses in any region of the world by supplying appropriately formatted input files. Source code is also supplied so advanced users can modify individual components to suit their needs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70147090','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70147090"><span>Time‐dependent renewal‐<span class="hlt">model</span> 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-<span class="hlt">model</span> <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-<span class="hlt">model</span> probabilities exceed Poisson results by more than 10% when the forecast duration exceeds ~20% of the mean recurrence 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 <span class="hlt">models</span>.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('http://adsabs.harvard.edu/abs/2014AGUFM.S53A4484I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.S53A4484I"><span>Estimation of completeness magnitude with a Bayesian <span class="hlt">modeling</span> of daily and weekly variations in <span class="hlt">earthquake</span> detectability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Iwata, T.</p> <p>2014-12-01</p> <p>In the analysis of seismic activity, assessment of <span class="hlt">earthquake</span> detectability of a seismic network is a fundamental issue. For this assessment, the completeness magnitude Mc, the minimum magnitude above which all <span class="hlt">earthquakes</span> are recorded, is frequently estimated. In most cases, Mc is estimated for an <span class="hlt">earthquake</span> catalog of duration longer than several weeks. However, owing to human activity, noise level in seismic data is higher on weekdays than on weekends, so that <span class="hlt">earthquake</span> detectability has a weekly variation [e.g., Atef et al., 2009, BSSA]; the consideration of such a variation makes a significant contribution to the precise assessment of <span class="hlt">earthquake</span> detectability and Mc. For a quantitative evaluation of the weekly variation, we introduced the statistical <span class="hlt">model</span> of a magnitude-frequency distribution of <span class="hlt">earthquakes</span> covering an entire magnitude range [Ogata & Katsura, 1993, GJI]. The frequency distribution is represented as the product of the Gutenberg-Richter law and a detection rate function. Then, the weekly variation in one of the <span class="hlt">model</span> parameters, which corresponds to the magnitude where the detection rate of <span class="hlt">earthquakes</span> is 50%, was estimated. Because <span class="hlt">earthquake</span> detectability also have a daily variation [e.g., Iwata, 2013, GJI], and the weekly and daily variations were estimated simultaneously by adopting a modification of a Bayesian smoothing spline method for temporal change in <span class="hlt">earthquake</span> detectability developed in Iwata [2014, Aust. N. Z. J. Stat.]. Based on the estimated variations in the parameter, the value of Mc was estimated. In this study, the Japan Meteorological Agency catalog from 2006 to 2010 was analyzed; this dataset is the same as analyzed in Iwata [2013] where only the daily variation in <span class="hlt">earthquake</span> detectability was considered in the estimation of Mc. A rectangular grid with 0.1° intervals covering in and around Japan was deployed, and the value of Mc was estimated for each gridpoint. Consequently, a clear weekly variation was revealed; the</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('http://adsabs.harvard.edu/abs/2010AGUFM.G11C..03F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.G11C..03F"><span>Rapid Assessment of <span class="hlt">Earthquakes</span> with Radar and Optical Geodetic Imaging and Finite Fault <span class="hlt">Models</span> (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fielding, E. J.; Sladen, A.; Simons, M.; Rosen, P. A.; Yun, S.; Li, Z.; Avouac, J.; Leprince, S.</p> <p>2010-12-01</p> <p><span class="hlt">Earthquake</span> responders need to know where the <span class="hlt">earthquake</span> has caused damage and what is the likely intensity of damage. The earliest information comes from global and regional seismic networks, which provide the magnitude and locations of the main <span class="hlt">earthquake</span> hypocenter and moment tensor centroid and also the locations of aftershocks. Location accuracy depends on the availability of seismic data close to the <span class="hlt">earthquake</span> source. Finite fault <span class="hlt">models</span> of the <span class="hlt">earthquake</span> slip can be derived from analysis of seismic waveforms alone, but the results can have large errors in the location of the fault ruptures and spatial distribution of slip, which are critical for estimating the distribution of shaking and damage. Geodetic measurements of ground displacements with GPS, LiDAR, or radar and optical imagery provide key spatial constraints on the location of the fault ruptures and distribution of slip. Here we describe the analysis of interferometric synthetic aperture radar (InSAR) and sub-pixel correlation (or pixel offset tracking) of radar and optical imagery to measure ground coseismic displacements for recent large <span class="hlt">earthquakes</span>, and lessons learned for rapid assessment of future events. These geodetic imaging techniques have been applied to the 2010 Leogane, Haiti; 2010 Maule, Chile; 2010 Baja California, Mexico; 2008 Wenchuan, China; 2007 Tocopilla, Chile; 2007 Pisco, Peru; 2005 Kashmir; and 2003 Bam, Iran <span class="hlt">earthquakes</span>, using data from ESA Envisat ASAR, JAXA ALOS PALSAR, NASA Terra ASTER and CNES SPOT5 satellite instruments and the NASA/JPL UAVSAR airborne system. For these events, the geodetic data provided unique information on the location of the fault or faults that ruptured and the distribution of slip that was not available from the seismic data and allowed the creation of accurate finite fault source <span class="hlt">models</span>. In many of these cases, the fault ruptures were on previously unknown faults or faults not believed to be at high risk of <span class="hlt">earthquakes</span>, so the area and degree of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PApGe.tmp....1T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PApGe.tmp....1T"><span>Dynamic Rupture Simulations Based on the Characterized Source <span class="hlt">Model</span> of 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>Tsuda, Kenichi; Iwase, Satoshi; Uratani, Hiroaki; Ogawa, Sachio; Watanabe, Takahide; Miyakoshi, Jun'ichi; Ampuero, Jean Paul</p> <p>2017-01-01</p> <p>The 2011 Off the Pacific Coast of Tohoku <span class="hlt">earthquake</span> (Tohoku <span class="hlt">earthquake</span>, M w 9.0) occurred on the Japan Trench and caused a devastating tsunami. Studies of this <span class="hlt">earthquake</span> have revealed complex features of its rupture process. In particular, the shallow parts of the fault (near the trench) hosted large slip and long period seismic wave radiation, whereas the deep parts of the rupture (near the coast) hosted smaller slip and strong radiation of short period seismic waves. Understanding such depth-dependent feature of the rupture process of the Tohoku <span class="hlt">earthquake</span> is necessary as it may occur during future mega-thrust <span class="hlt">earthquakes</span> in this and other regions. In this study, we investigate the "characterized source <span class="hlt">model</span>" of the Tohoku <span class="hlt">earthquake</span> through dynamic rupture simulations. This source <span class="hlt">model</span> divides the fault plane into several parts characterized by different size and frictional strength (main asperity, background area, etc.) and is widely used in Japan for the prediction of strong ground motion and tsunami through kinematic rupture simulations. Our characterized source <span class="hlt">model</span> of the Tohoku <span class="hlt">earthquake</span> comprises a large shallow asperity with moderate frictional strength, small deep asperities with high frictional strength, a background area with low frictional strength, and an area with dynamic weakening close to the trench (low dynamic friction coefficient as arising from, e.g., thermal pressurization). The results of our dynamic rupture simulation reproduce the main depth-dependent feature of the rupture process of the Tohoku <span class="hlt">earthquake</span>. We also find that the width of the area close to the trench (equal to the distance from the trench to the shallow asperity, interpreted as the size of the accretionary prism) and the presence of dynamic weakening in this area have a significant influence on the final slip distribution. These results are useful to construct characterized source <span class="hlt">models</span> for other subduction zones with different scale of the accretionary prism, such</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.T22B..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.T22B..01R"><span><span class="hlt">Modeling</span> geometrically complex faults over many <span class="hlt">earthquake</span> cycles via neural network acceleration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robinson DeVries, P.; Thompson, T. B.; Meade, B. J.</p> <p>2016-12-01</p> <p>Deformation throughout the <span class="hlt">earthquake</span> cycle along geometrically complex fault systems contributes to, and may dominate, the deformation budget of evolving tectonic structures. One of the greatest challenges to understanding the effects of repeated <span class="hlt">earthquake</span> cycle activity on large-scale tectonic structures is the computational cost of viscoelastic <span class="hlt">earthquake</span> cycle <span class="hlt">models</span>. These computationally intensive viscoelastic codes may need to be evaluated at thousands of times and locations, and as a result, studies tend to adopt a few fixed rheological structures and <span class="hlt">model</span> geometries, and examine the predicted time-dependent deformation over short (<10 yr) time periods at a given depth after a large <span class="hlt">earthquake</span>. Training a deep neural network to learn an efficient representation of viscoelastic solutions - at any time, location, and for a large range of rheological structures - allows these calculations to be done quickly, with dense spatial and temporal resolution. Preliminary tests suggest this method can accelerate viscoelastic calculations by a factor of 500, and perhaps orders of magnitude more. We demonstrate how this machine learning approach enables the <span class="hlt">modeling</span> of geometrically complex faults over thousands of <span class="hlt">earthquake</span> cycles with high spatial and temporal resolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007ChPhy..16.2665L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007ChPhy..16.2665L"><span>Lie symmetry algebra of one-dimensional <span class="hlt">nonconservative</span> dynamical systems</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Cui-Mei; Wu, Run-Heng; Fu, Jing-Li</p> <p>2007-09-01</p> <p>Lie symmetry algebra of linear <span class="hlt">nonconservative</span> dynamical systems is studied in this paper. By using 1-1 mapping, the Lie point and Lie contact symmetry algebras are obtained from two independent solutions of the one-dimensional linear equations of motion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4660942','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4660942"><span><span class="hlt">Nonconservative</span> current-driven dynamics: beyond the nanoscale</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Todorov, Tchavdar N; Dundas, Daniel</p> <p>2015-01-01</p> <p>Summary Long metallic nanowires combine crucial factors for <span class="hlt">nonconservative</span> current-driven atomic motion. These systems have degenerate vibrational frequencies, clustered about a Kohn anomaly in the dispersion relation, that can couple under current to form nonequilibrium modes of motion growing exponentially in time. Such motion is made possible by <span class="hlt">nonconservative</span> current-induced forces on atoms, and we refer to it generically as the waterwheel effect. Here the connection between the waterwheel effect and the stimulated directional emission of phonons propagating along the electron flow is discussed in an intuitive manner. Nonadiabatic molecular dynamics show that waterwheel modes self-regulate by reducing the current and by populating modes in nearby frequency, leading to a dynamical steady state in which <span class="hlt">nonconservative</span> forces are counter-balanced by the electronic friction. The waterwheel effect can be described by an appropriate effective nonequilibrium dynamical response matrix. We show that the current-induced parts of this matrix in metallic systems are long-ranged, especially at low bias. This nonlocality is essential for the characterisation of <span class="hlt">nonconservative</span> atomic dynamics under current beyond the nanoscale. PMID:26665086</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S33A2751C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S33A2751C"><span>Seismic hazard assessment for Myanmar: <span class="hlt">Earthquake</span> <span class="hlt">model</span> database, ground-motion scenarios, and probabilistic assessments</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. H.; Wang, Y.; Thant, M.; Maung Maung, P.; Sieh, K.</p> <p>2015-12-01</p> <p>We have constructed an <span class="hlt">earthquake</span> and fault database, conducted a series of ground-shaking scenarios, and proposed seismic hazard maps for all of Myanmar and hazard curves for selected cities. Our <span class="hlt">earthquake</span> database integrates the ISC, ISC-GEM and global ANSS Comprehensive Catalogues, and includes harmonized magnitude scales without duplicate events. Our active fault database includes active fault data from previous studies. Using the parameters from these updated databases (i.e., the Gutenberg-Richter relationship, slip rate, maximum magnitude and the elapse time of last events), we have determined the <span class="hlt">earthquake</span> recurrence <span class="hlt">models</span> of seismogenic sources. To evaluate the ground shaking behaviours in different tectonic regimes, we conducted a series of tests by matching the <span class="hlt">modelled</span> ground motions to the felt intensities of <span class="hlt">earthquakes</span>. Through the case of the 1975 Bagan <span class="hlt">earthquake</span>, we determined that Atkinson and Moore's (2003) scenario using the ground motion prediction equations (GMPEs) fits the behaviours of the subduction events best. Also, the 2011 Tarlay and 2012 Thabeikkyin events suggested the GMPEs of Akkar and Cagnan (2010) fit crustal <span class="hlt">earthquakes</span> best. We thus incorporated the best-fitting GMPEs and site conditions based on Vs30 (the average shear-velocity down to 30 m depth) from analysis of topographic slope and microtremor array measurements to assess seismic hazard. The hazard is highest in regions close to the Sagaing Fault and along the Western Coast of Myanmar as seismic sources there have <span class="hlt">earthquakes</span> occur at short intervals and/or last events occurred a long time ago. The hazard curves for the cities of Bago, Mandalay, Sagaing, Taungoo and Yangon show higher hazards for sites close to an active fault or with a low Vs30, e.g., the downtown of Sagaing and Shwemawdaw Pagoda in Bago.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1072/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1072/"><span>Comprehensive Areal <span class="hlt">Model</span> of <span class="hlt">Earthquake</span>-Induced Landslides: Technical Specification and User Guide</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Miles, Scott B.; Keefer, David K.</p> <p>2007-01-01</p> <p>This report describes the complete design of a comprehensive areal <span class="hlt">model</span> of earthquakeinduced landslides (CAMEL). This report presents the design process, technical specification of CAMEL. It also provides a guide to using the CAMEL source code and template ESRI ArcGIS map document file for applying CAMEL, both of which can be obtained by contacting the authors. CAMEL is a regional-scale <span class="hlt">model</span> of <span class="hlt">earthquake</span>-induced landslide hazard developed using fuzzy logic systems. CAMEL currently estimates areal landslide concentration (number of landslides per square kilometer) of six aggregated types of <span class="hlt">earthquake</span>-induced landslides - three types each for rock and soil.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JSV...407..209X','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JSV...407..209X"><span>Stochastic analysis <span class="hlt">model</span> for vehicle-track coupled systems subject to <span class="hlt">earthquakes</span> and track random irregularities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Xu, Lei; Zhai, Wanming</p> <p>2017-10-01</p> <p>This paper devotes to develop a computational <span class="hlt">model</span> for stochastic analysis and reliability assessment of vehicle-track systems subject to <span class="hlt">earthquakes</span> and track random irregularities. In this <span class="hlt">model</span>, the <span class="hlt">earthquake</span> is expressed as non-stationary random process simulated by spectral representation and random function, and the track random irregularities with ergodic properties on amplitudes, wavelengths and probabilities are characterized by a track irregularity probabilistic <span class="hlt">model</span>, and then the number theoretical method (NTM) is applied to effectively select representative samples of <span class="hlt">earthquakes</span> and track random irregularities. Furthermore, a vehicle-track coupled <span class="hlt">model</span> is presented to obtain the dynamic responses of vehicle-track systems due to the <span class="hlt">earthquakes</span> and track random irregularities at time-domain, and the probability density evolution method (PDEM) is introduced to describe the evolutionary process of probability from excitation input to response output by assuming the vehicle-track system as a probabilistic conservative system, which lays the foundation on reliability assessment of vehicle-track systems. The effectiveness of the proposed <span class="hlt">model</span> is validated by comparing to the results of Monte-Carlo method from statistical viewpoint. As an illustrative example, the random vibrations of a high-speed railway vehicle running on the track slabs excited by lateral seismic waves and track random irregularities are analyzed, from which some significant conclusions can be drawn, e.g., track irregularities will additionally promote the dynamic influence of <span class="hlt">earthquakes</span> especially on maximum values and dispersion degree of responses; the characteristic frequencies or frequency ranges respectively governed by <span class="hlt">earthquakes</span> and track random irregularities are greatly different, moreover, the lateral seismic waves will dominate or even change the characteristic frequencies of system responses of some lateral dynamic indices at low frequency.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70027428','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70027428"><span>Rapid tsunami <span class="hlt">models</span> and <span class="hlt">earthquake</span> source parameters: Far-field and local applications</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, E.L.</p> <p>2005-01-01</p> <p>Rapid tsunami <span class="hlt">models</span> have recently been developed to forecast far-field tsunami amplitudes from initial <span class="hlt">earthquake</span> information (magnitude and hypocenter). <span class="hlt">Earthquake</span> source parameters that directly affect tsunami generation as used in rapid tsunami <span class="hlt">models</span> are examined, with particular attention to local versus far-field application of those <span class="hlt">models</span>. First, validity of the assumption that the focal mechanism and type of faulting for tsunamigenic <span class="hlt">earthquakes</span> is similar in a given region can be evaluated by measuring the seismic consistency of past events. Second, the assumption that slip occurs uniformly over an area of rupture will most often underestimate the amplitude and leading-wave steepness of the local tsunami. Third, sometimes large magnitude <span class="hlt">earthquakes</span> will exhibit a high degree of spatial heterogeneity such that tsunami sources will be composed of distinct sub-events that can cause constructive and destructive interference in the wavefield away from the source. Using a stochastic source <span class="hlt">model</span>, it is demonstrated that local tsunami amplitudes vary by as much as a factor of two or more, depending on the local bathymetry. If other <span class="hlt">earthquake</span> source parameters such as focal depth or shear modulus are varied in addition to the slip distribution patterns, even greater uncertainty in local tsunami amplitude is expected for <span class="hlt">earthquakes</span> of similar magnitude. Because of the short amount of time available to issue local warnings and because of the high degree of uncertainty associated with local, <span class="hlt">model</span>-based forecasts as suggested by this study, direct wave height observations and a strong public education and preparedness program are critical for those regions near suspected tsunami sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005PApGe.162.1113S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005PApGe.162.1113S"><span>Power-law Distributions of Offspring and Generation Numbers in Branching <span class="hlt">Models</span> of <span class="hlt">Earthquake</span> Triggering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saichev, A.; Helmstetter, A.; Sornette, D.</p> <p>2005-06-01</p> <p>We consider a general stochastic branching process,which is relevant to <span class="hlt">earthquakes</span> as well as to many other systems, and we study the distributions of the total number of offsprings (direct and indirect aftershocks in seismicity) and of the total number of generations before extinction. We apply our results to a branching <span class="hlt">model</span> of triggered seismicity, the ETAS (epidemic-type aftershock sequence) <span class="hlt">model</span>. The ETAS <span class="hlt">model</span> assumes that each <span class="hlt">earthquake</span> can trigger other <span class="hlt">earthquakes</span> (“aftershocks”). An aftershock sequence results in this <span class="hlt">model</span> from the cascade of aftershocks of each past <span class="hlt">earthquake</span>. Due to the large fluctuations of the number of aftershocks triggered directly by any <span class="hlt">earthquake</span> (“fertility”), there is a large variability of the total number of aftershocks from one sequence to another, for the same mainshock magnitude. We study the regime in which the distribution of fertilities μ is characterized by a power law ~1/μ1+γ. For <span class="hlt">earthquakes</span> we expect such a power-distribution of fertilities with γ=b/α based on the Gutenberg-Richter magnitude distribution ~ 10-bm and on the increase ~ 10-αm of the number of aftershocks with the mainshock magnitude m. We derive the asymptotic distributions pr(r) and pg(g) of the total number r of offsprings and of the total number g of generations until extinction following a mainshock. In the regime γ < 2 for which the distribution of fertilities has an infinite variance, we find This should be compared with the distributions obtained for standard branching processes with finite variance. These predictions are checked by numerical simulations. Our results apply directly to the ETAS <span class="hlt">model</span> whose preferred values α=0.8 1 and b=1 puts it in the regime where the distribution of fertilities has an infinite variance. More generally, our results apply to any stochastic branching process with a power-law distribution of offsprings per mother</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1817231S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1817231S"><span>Mechanisms of postseismic relaxation after a great subduction <span class="hlt">earthquake</span> constrained by cross-scale thermomechanical <span class="hlt">model</span> and geodetic observations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sobolev, Stephan; Muldashev, Iskander</p> <p>2016-04-01</p> <p>According to conventional view, postseismic relaxation process after a great megathrust <span class="hlt">earthquake</span> is dominated by fault-controlled afterslip during first few months to year, and later by visco-elastic relaxation in mantle wedge. We test this idea by cross-scale thermomechanical <span class="hlt">models</span> of seismic cycle that employs elasticity, mineral-physics constrained non-linear transient viscous rheology and rate-and-state friction plasticity. As initial conditions for the <span class="hlt">models</span> we use thermomechanical <span class="hlt">models</span> of subduction zones at geological time-scale including a narrow subduction channel with low static friction for two settings, similar to the Southern Chile in the region of the great Chile <span class="hlt">Earthquake</span> of 1960 and Japan in the region of Tohoku <span class="hlt">Earthquake</span> of 2011. We next introduce in the same <span class="hlt">models</span> classic rate-and state friction law in subduction channels, leading to stick-slip instability. The <span class="hlt">models</span> start to generate spontaneous <span class="hlt">earthquake</span> sequences and <span class="hlt">model</span> parameters are set to closely replicate co-seismic deformations of Chile and Japan <span class="hlt">earthquakes</span>. In order to follow in details deformation process during the entire seismic cycle and multiple seismic cycles we use adaptive time-step algorithm changing integration step from 40 sec during the <span class="hlt">earthquake</span> to minute-5 year during postseismic and interseismic processes. We show that for the case of the Chile <span class="hlt">earthquake</span> visco-elastic relaxation in the mantle wedge becomes dominant relaxation process already since 1 hour after the <span class="hlt">earthquake</span>, while for the smaller Tohoku <span class="hlt">earthquake</span> this happens some days after the <span class="hlt">earthquake</span>. We also show that our <span class="hlt">model</span> for Tohoku <span class="hlt">earthquake</span> is consistent with the geodetic observations for the day-to-4year time range. We will demonstrate and discuss <span class="hlt">modeled</span> deformation patterns during seismic cycles and identify the regions where the effects of afterslip and visco-elastic relaxation can be best distinguished.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028348','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028348"><span>Rupture <span class="hlt">models</span> for the A.D. 900-930 Seattle fault <span class="hlt">earthquake</span> from uplifted shorelines</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>ten Brink, U.S.; Song, J.; Bucknam, R.C.</p> <p>2006-01-01</p> <p>A major <span class="hlt">earthquake</span> on the Seattle fault, Washington, ca. A.D. 900-930 was first inferred from uplifted shorelines and tsunami deposits. Despite follow-up geophysical and geological investigations, the rupture parameters of the <span class="hlt">earthquake</span> and the geometry of the fault are uncertain. Here we estimate the fault geometry, slip direction, and magnitude of the <span class="hlt">earthquake</span> by <span class="hlt">modeling</span> shoreline elevation change. The best fitting <span class="hlt">model</span> geometry is a reverse fault with a shallow roof ramp consisting of at least two back thrusts. The best fitting rupture is a SW-NE ohlique reverse slip with horizontal shortening of 15 m, rupture depth of 12.5 km, and magnitude Mw = 7.5. ?? 2006 Geological Society of America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5891099','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5891099"><span>Family number <span class="hlt">non-conservation</span> induced by the supersymmetric mixing of scalar leptons</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Levine, M.J.S.</p> <p>1987-08-01</p> <p>The most egregious aspect of (N = 1) supersymmetric theories is that each particle state is accompanied by a 'super-partner', a state with identical quantum numbers save that it differs in spin by one half unit. For the leptons these are scalars and are called ''sleptons'', or scalar leptons. These consist of the charged sleptons (selectron, smuon, stau) and the scalar neutrinos ('sneutrinos'). We examine a <span class="hlt">model</span> of supersymmetry with soft breaking terms in the electroweak sector. Explicit mixing among the scalar leptons results in a number of effects, principally <span class="hlt">non-conservation</span> of lepton family number. Comparison with experiment permits us to place constraints upon the <span class="hlt">model</span>. 49 refs., 12 figs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19..407D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19..407D"><span>Improving vulnerability <span class="hlt">models</span>: lessons learned from a comparison between flood and <span class="hlt">earthquake</span> assessments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Ruiter, Marleen; Ward, Philip; Daniell, James; Aerts, Jeroen</p> <p>2017-04-01</p> <p>In a cross-discipline study, an extensive literature review has been conducted to increase the understanding of vulnerability indicators used in both <span class="hlt">earthquake</span>- and flood vulnerability assessments, and to provide insights into potential improvements of <span class="hlt">earthquake</span> and flood vulnerability assessments. It identifies and compares indicators used to quantitatively assess <span class="hlt">earthquake</span> and flood vulnerability, and discusses their respective differences and similarities. Indicators have been categorized into Physical- and Social categories, and further subdivided into (when possible) measurable and comparable indicators. Physical vulnerability indicators have been differentiated to exposed assets such as buildings and infrastructure. Social indicators are grouped in subcategories such as demographics, economics and awareness. Next, two different vulnerability <span class="hlt">model</span> types have been described that use these indicators: index- and curve-based vulnerability <span class="hlt">models</span>. A selection of these <span class="hlt">models</span> (e.g. HAZUS) have been described, and compared on several characteristics such as temporal- and spatial aspects. It appears that <span class="hlt">earthquake</span> vulnerability methods are traditionally strongly developed towards physical attributes at an object scale and used in vulnerability curve <span class="hlt">models</span>, whereas flood vulnerability studies focus more on indicators applied to aggregated land-use scales. Flood risk studies could be improved using approaches from <span class="hlt">earthquake</span> studies, such as incorporating more detailed lifeline and building indicators, and developing object-based vulnerability curve assessments of physical vulnerability, for example by defining building material based flood vulnerability curves. Related to this, is the incorporation of time of the day based building occupation patterns (at 2am most people will be at home while at 2pm most people will be in the office). <span class="hlt">Earthquake</span> assessments could learn from flood studies when it comes to the refined selection of social vulnerability indicators</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 <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">model</span>, 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 <span class="hlt">model</span> for two time-windows: 5 and 10 years. Each <span class="hlt">model</span> to be tested defines a forecasted <span class="hlt">earthquake</span> rate 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('http://adsabs.harvard.edu/abs/2016WRR....52.9164M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016WRR....52.9164M"><span>Innovative framework to simulate the fate and transport of <span class="hlt">nonconservative</span> constituents in urban combined sewer catchments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Morales, V. M.; Quijano, J. C.; Schmidt, A.; Garcia, M. H.</p> <p>2016-11-01</p> <p>We have developed a probabilistic <span class="hlt">model</span> to simulate the fate and transport of <span class="hlt">nonconservative</span> constituents in urban watersheds. The approach implemented here extends previous studies that rely on the geomorphological instantaneous unit hydrograph concept to include <span class="hlt">nonconservative</span> constituents. This is implemented with a factor χ that affects the transfer functions and therefore accounts for the loss (gain) of mass associated with the constituent as it travels through the watershed. Using this framework, we developed an analytical solution for the dynamics of dissolved oxygen (DO) and biochemical oxygen demand (BOD) in urban networks based on the Streeter and Phelps <span class="hlt">model</span>. This <span class="hlt">model</span> breaks down the catchment into a discreet number of possible flow paths through the system, requiring less data and implementation effort than well-established deterministic <span class="hlt">models</span>. Application of the <span class="hlt">model</span> to one sewer catchment in the Chicago area with available BOD information proved its ability to predict the BOD concentration observed in the measurements. In addition, comparison of the <span class="hlt">model</span> with a calibrated Storm Water Management <span class="hlt">Model</span> (SWMM) of another sewer catchment from the Chicago area showed that the <span class="hlt">model</span> predicted the BOD concentration as well as the widely accepted SWMM. The developed <span class="hlt">model</span> proved to be a suitable alternative to simulate the fate and transport of constituents in urban catchments with limited and uncertain input data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/20771607','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/20771607"><span>Parity <span class="hlt">nonconservation</span> in elastic p-vectorp scattering</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Liu, C.-P.; Hyun, C.H.; Desplanques, B.</p> <p>2006-06-15</p> <p>By looking at the parity-<span class="hlt">nonconserving</span> (PNC) asymmetries for different energies in p-vectorp scattering, it is in principle possible to determine the PNC {rho}NN and {omega}NN couplings of a single-meson-exchange <span class="hlt">model</span> of the PNC NN force. Analysis of the experimental data at 13.6, 45, and 221 MeV was performed by Carlson et al., [Phys. Rev. C 65, 035502 (2002)] who concluded the data were in agreement with the uncertainties accorded the original DDH estimates for the PNC meson-nucleon couplings. In this work it is shown first that a comparison with updated hadronic predictions of these couplings suggests the existence of some discrepancy for the PNC {omega}NN coupling. The effect of varying the strong coupling constants and introducing cutoffs in the one-boson-exchange weak potential is then investigated. As expected, the resulting asymmetry is quite sensitive to these parameters regardless of the energy. However, the above mentioned discrepancy persists. The dependence of this conclusion on various ingredients entering an improved description of the PNC NN force is also examined. Additional mechanisms include the two-pion resonance nature of the rho meson and some momentum dependence of the isoscalar PNC {rho}NN vertex. None of these corrections removes or even alleviates the above discrepancy. Their impact on the theoretical determination of the vector meson-nucleon couplings, the description of the PNC force in terms of single-meson exchange, and the interpretation of measurements are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JETP..124..731D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JETP..124..731D"><span><span class="hlt">Nonconservation</span> of lepton current and asymmetry of relic neutrinos</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dvornikov, M. S.; Semikoz, V. B.</p> <p>2017-05-01</p> <p>The neutrino asymmetry, {n_v} - {n_{\\bar v}} , in the plasma of the early Universe generated both before and after the electroweak phase transition (EWPT) is calculated. It is well known that in the Standard <span class="hlt">Model</span> the leptogenesis before the EWPT, in particular, for neutrinos, owes to the Abelian anomaly in a massless hypercharge field. At the same time, the generation of neutrino asymmetry in the Higgs phase after the EWPT has not been considered previously due to the absence of any quantum anomaly in an external electromagnetic field for such electroneutral particles as neutrinos, in contrast to the Adler anomaly for charged left- and right-handed massless electrons in the same electromagnetic field. Using the Boltzmann equation for neutrinos modified to include the Berry curvature term in momentum space, we establish a violation of the macroscopic neutrino current in the plasma after the EWPT and exactly reproduce the <span class="hlt">non-conservation</span> of the lepton current in the symmetric phase before the EWPT that owes to the contribution of the triangle anomaly in an external hypercharge field but already without computing the corresponding Feynman diagrams. We apply the new kinetic equation to calculate the neutrino asymmetry by taking into account the Berry curvature and the electroweak interaction with plasma particles in the Higgs phase, including that after the neutrino decoupling in the absence of their collisions in the plasma. We find that this asymmetry is too small for observations. Thus, a difference between the relic neutrino and antineutrino densities, if it exists, must appear already in the symmetric phase of the early Universe before the EWPT.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..1113961A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..1113961A"><span>GEM1: First-year <span class="hlt">modeling</span> and IT activities for the Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Anderson, G.; Giardini, D.; Wiemer, S.</p> <p>2009-04-01</p> <p>GEM is a public-private partnership initiated by the Organisation for Economic Cooperation and Development (OECD) to build an independent standard for <span class="hlt">modeling</span> and communicating <span class="hlt">earthquake</span> risk worldwide. GEM is aimed at providing authoritative, open information about seismic risk and decision tools to support mitigation. GEM will also raise risk awareness and help post-disaster economic development, with the ultimate goal of reducing the toll of future <span class="hlt">earthquakes</span>. GEM will provide a unified set of seismic hazard, risk, and loss <span class="hlt">modeling</span> tools based on a common global IT infrastructure and consensus standards. These tools, systems, and standards will be developed in partnership with organizations around the world, with coordination by the GEM Secretariat and its Secretary General. GEM partners will develop a variety of global components, including a unified <span class="hlt">earthquake</span> catalog, fault database, and ground motion prediction equations. To ensure broad representation and community acceptance, GEM will include local knowledge in all <span class="hlt">modeling</span> activities, incorporate existing detailed <span class="hlt">models</span> where possible, and independently test all resulting tools and <span class="hlt">models</span>. When completed in five years, GEM will have a versatile, penly accessible <span class="hlt">modeling</span> environment that can be updated as necessary, and will provide the global standard for seismic hazard, risk, and loss <span class="hlt">models</span> to government ministers, scientists and engineers, financial institutions, and the public worldwide. GEM is now underway with key support provided by private sponsors (Munich Reinsurance Company, Zurich Financial Services, AIR Worldwide Corporation, and Willis Group Holdings); countries including Belgium, Germany, Italy, Singapore, Switzerland, and Turkey; and groups such as the European Commission. The GEM Secretariat has been selected by the OECD and will be hosted at the Eucentre at the University of Pavia in Italy; the Secretariat is now formalizing the creation of the GEM Foundation. Some of GEM's global</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..12.5812H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..12.5812H"><span>Large Historical <span class="hlt">Earthquakes</span> and Tsunami Hazards in the Western Mediterranean: Source Characteristics and <span class="hlt">Modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harbi, Assia; Meghraoui, Mustapha; Belabbes, Samir; Maouche, Said</p> <p>2010-05-01</p> <p>The western Mediterranean region was the site of numerous large <span class="hlt">earthquakes</span> in the past. Most of these <span class="hlt">earthquakes</span> are located at the East-West trending Africa-Eurasia plate boundary and along the coastline of North Africa. The most recent recorded tsunamigenic <span class="hlt">earthquake</span> occurred in 2003 at Zemmouri-Boumerdes (Mw 6.8) and generated ~ 2-m-high tsunami wave. The destructive wave affected the Balearic Islands and Almeria in southern Spain and Carloforte in southern Sardinia (Italy). The <span class="hlt">earthquake</span> provided a unique opportunity to gather instrumental records of seismic waves and tide gauges in the western Mediterranean. A database that includes a historical catalogue of main events, seismic sources and related fault parameters was prepared in order to assess the tsunami hazard of this region. In addition to the analysis of the 2003 records, we study the 1790 Oran and 1856 Jijel historical tsunamigenic <span class="hlt">earthquakes</span> (Io = IX and X, respectively) that provide detailed observations on the heights and extension of past tsunamis and damage in coastal zones. We performed the <span class="hlt">modelling</span> of wave propagation using NAMI-DANCE code and tested different fault sources from synthetic tide gauges. We observe that the characteristics of seismic sources control the size and directivity of tsunami wave propagation on both northern and southern coasts of the western Mediterranean.</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/2013AGUFMNH32A..02N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH32A..02N"><span>Toward a Global <span class="hlt">Model</span> for Predicting <span class="hlt">Earthquake</span>-Induced Landslides in Near-Real Time</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nowicki, M. A.; Wald, D. J.; Hamburger, M. W.; Hearne, M.; Thompson, E.</p> <p>2013-12-01</p> <p>We present a newly developed statistical <span class="hlt">model</span> for estimating the distribution of <span class="hlt">earthquake</span>-triggered landslides in near-real time, which is designed for use in the USGS Prompt Assessment of Global <span class="hlt">Earthquakes</span> for Response (PAGER) and ShakeCast systems. We use standardized estimates of ground shaking from the USGS ShakeMap Atlas 2.0 to develop an empirical landslide probability <span class="hlt">model</span> by combining shaking estimates with broadly available landslide susceptibility proxies, including topographic slope, surface geology, and climatic parameters. While the initial <span class="hlt">model</span> was based on four <span class="hlt">earthquakes</span> for which digitally mapped landslide inventories and well constrained ShakeMaps are available--the Guatemala (1976), Northridge, California (1994), Chi-Chi, Taiwan (1999), and Wenchuan, China (2008) <span class="hlt">earthquakes</span>, our improved <span class="hlt">model</span> includes observations from approximately ten other events from a variety of tectonic and geomorphic settings for which we have obtained landslide inventories. Using logistic regression, this database is used to build a predictive <span class="hlt">model</span> of the probability of landslide occurrence. We assess the performance of the regression <span class="hlt">model</span> using statistical goodness-of-fit metrics to determine which combination of the tested landslide proxies provides the optimum prediction of observed landslides while minimizing ';false alarms' in non-landslide zones. Our initial results indicate strong correlations with peak ground acceleration and maximum slope, and weaker correlations with surface geological and soil wetness proxies. In terms of the original four events included, the global <span class="hlt">model</span> predicts landslides most accurately when applied to the Wenchuan and Chi-Chi events, and less accurately when applied to the Northridge and Guatemala datasets. Combined with near-real time ShakeMaps, the <span class="hlt">model</span> can be used to make generalized predictions of whether or not landslides are likely to occur (and if so, where) for future <span class="hlt">earthquakes</span> around the globe, and these estimates</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70030430','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70030430"><span>Regional intensity attenuation <span class="hlt">models</span> for France and the estimation of magnitude and location of historical <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>Bakun, W.H.; Scotti, O.</p> <p>2006-01-01</p> <p>Intensity assignments for 33 calibration <span class="hlt">earthquakes</span> were used to develop intensity attenuation <span class="hlt">models</span> for the Alps, Armorican, Provence, Pyrenees and Rhine regions of France. Intensity decreases with ?? most rapidly in the French Alps, Provence and Pyrenees regions, and least rapidly in the Armorican and Rhine regions. The comparable Armorican and Rhine region attenuation <span class="hlt">models</span> are aggregated into a French stable continental region <span class="hlt">model</span> and the comparable Provence and Pyrenees region <span class="hlt">models</span> are aggregated into a Southern France <span class="hlt">model</span>. We analyse MSK intensity assignments using the technique of Bakun & Wentworth, which provides an objective method for estimating epicentral location and intensity magnitude MI. MI for the 1356 October 18 <span class="hlt">earthquake</span> in the French stable continental region is 6.6 for a location near Basle, Switzerland, and moment magnitude M is 5.9-7.2 at the 95 per cent (??2??) confidence level. MI for the 1909 June 11 Trevaresse (Lambesc) <span class="hlt">earthquake</span> near Marseilles in the Southern France region is 5.5, and M is 4.9-6.0 at the 95 per cent confidence level. Bootstrap resampling techniques are used to calculate objective, reproducible 67 per cent and 95 per cent confidence regions for the locations of historical <span class="hlt">earthquakes</span>. These confidence regions for location provide an attractive alternative to the macroseismic epicentre and qualitative location uncertainties used heretofore. ?? 2006 The Authors Journal compilation ?? 2006 RAS.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NPGeo..24..179B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NPGeo..24..179B"><span>Sandpile-based <span class="hlt">model</span> for capturing magnitude distributions and spatiotemporal clustering and separation in regional <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>Batac, Rene C.; Paguirigan, Antonino A., Jr.; Tarun, Anjali B.; Longjas, Anthony G.</p> <p>2017-04-01</p> <p>We propose a cellular automata <span class="hlt">model</span> for <span class="hlt">earthquake</span> occurrences patterned after the sandpile <span class="hlt">model</span> of self-organized criticality (SOC). By incorporating a single parameter describing the probability to target the most susceptible site, the <span class="hlt">model</span> successfully reproduces the statistical signatures of seismicity. The energy distributions closely follow power-law probability density functions (PDFs) with a scaling exponent of around -1. 6, consistent with the expectations of the Gutenberg-Richter (GR) law, for a wide range of the targeted triggering probability values. Additionally, for targeted triggering probabilities within the range 0.004-0.007, we observe spatiotemporal distributions that show bimodal behavior, which is not observed previously for the original sandpile. For this critical range of values for the probability, <span class="hlt">model</span> statistics show remarkable comparison with long-period empirical data from <span class="hlt">earthquakes</span> from different seismogenic regions. The proposed <span class="hlt">model</span> has key advantages, the foremost of which is the fact that it simultaneously captures the energy, space, and time statistics of <span class="hlt">earthquakes</span> by just introducing a single parameter, while introducing minimal parameters in the simple rules of the sandpile. We believe that the critical targeting probability parameterizes the memory that is inherently present in <span class="hlt">earthquake</span>-generating regions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PApGe.172...23T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PApGe.172...23T"><span>The Negative Binomial Distribution as a Renewal <span class="hlt">Model</span> for the Recurrence of Large <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>Tejedor, Alejandro; Gómez, Javier B.; Pacheco, Amalio F.</p> <p>2015-01-01</p> <p>The negative binomial distribution is presented as the waiting time distribution of a cyclic Markov <span class="hlt">model</span>. This cycle simulates the seismic cycle in a fault. As an example, this <span class="hlt">model</span>, which can describe recurrences with aperiodicities between 0 and 0.5, is used to fit the Parkfield, California <span class="hlt">earthquake</span> series in the San Andreas Fault. The performance of the <span class="hlt">model</span> in the forecasting is expressed in terms of error diagrams and compared with other recurrence <span class="hlt">models</span> from literature.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoJI.198..671W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoJI.198..671W"><span>Joint <span class="hlt">earthquake</span> source inversions using seismo-geodesy and 3-D earth <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weston, J.; Ferreira, A. M. G.; Funning, G. J.</p> <p>2014-08-01</p> <p>A joint <span class="hlt">earthquake</span> source inversion technique is presented that uses InSAR and long-period teleseismic data, and, for the first time, takes 3-D Earth structure into account when <span class="hlt">modelling</span> seismic surface and body waves. Ten average source parameters (Moment, latitude, longitude, depth, strike, dip, rake, length, width and slip) are estimated; hence, the technique is potentially useful for rapid source inversions of moderate magnitude <span class="hlt">earthquakes</span> using multiple data sets. Unwrapped interferograms and long-period seismic data are jointly inverted for the location, fault geometry and seismic moment, using a hybrid downhill Powell-Monte Carlo algorithm. While the InSAR data are <span class="hlt">modelled</span> assuming a rectangular dislocation in a homogeneous half-space, seismic data are <span class="hlt">modelled</span> using the spectral element method for a 3-D earth <span class="hlt">model</span>. The effect of noise and lateral heterogeneity on the inversions is investigated by carrying out realistic synthetic tests for various <span class="hlt">earthquakes</span> with different faulting mechanisms and magnitude (Mw 6.0-6.6). Synthetic tests highlight the improvement in the constraint of fault geometry (strike, dip and rake) and moment when InSAR and seismic data are combined. Tests comparing the effect of using a 1-D or 3-D earth <span class="hlt">model</span> show that long-period surface waves are more sensitive than long-period body waves to the change in earth <span class="hlt">model</span>. Incorrect source parameters, particularly incorrect fault dip angles, can compensate for systematic errors in the assumed Earth structure, leading to an acceptable data fit despite large discrepancies in source parameters. Three real <span class="hlt">earthquakes</span> are also investigated: Eureka Valley, California (1993 May 17, Mw 6.0), Aiquile, Bolivia (1998 February 22, Mw 6.6) and Zarand, Iran (2005 May 22, Mw 6.5). These events are located in different tectonic environments and show large discrepancies between InSAR and seismically determined source <span class="hlt">models</span>. Despite the 40-50 km discrepancies in location between previous geodetic and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....6760D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....6760D"><span><span class="hlt">Earthquake</span> triggering in the peri-adriatic regions induced by stress diffusion: insights from numerical <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>D'Onza, F.; Viti, M.; Mantovani, E.; Albarello, D.</p> <p>2003-04-01</p> <p><span class="hlt">EARTHQUAKE</span> TRIGGERING IN THE PERI-ADRIATIC REGIONS INDUCED BY STRESS DIFFUSION: INSIGHTS FROM NUMERICAL <span class="hlt">MODELLING</span> F. D’Onza (1), M. Viti (1), E. Mantovani (1) and D. Albarello (1) (1) Dept. of Earth Sciences, University of Siena - Italy (donza@unisi.it/Fax:+39-0577-233820) Significant evidence suggests that major <span class="hlt">earthquakes</span> in the peri-Adriatic Balkan zones may influence the seismicity pattern in the Italian area. In particular, a seismic correlation has been recognized between major <span class="hlt">earthquakes</span> in the southern Dinaric belt and those in southern Italy. It is widely recognized that such kind of regularities may be an effect of postseismic relaxation triggered by strong <span class="hlt">earthquakes</span>. In this note, we describe an attempt to quantitatively investigate, by numerical <span class="hlt">modelling</span>, the reliability of the above interpretation. In particular, we have explored the possibility to explain the last example of the presumed correlation (triggering event: April, 1979 Montenegro <span class="hlt">earthquake</span>, MS=6.7; induced event: November, 1980 Irpinia event, MS=6.9) as an effect of postseismic relaxation through the Adriatic plate. The triggering event is <span class="hlt">modelled</span> by imposing a sudden dislocation in the Montenegro seismic fault, taking into account the fault parameters (length and average slip) recognized from seismological observations. The perturbation induced by the seismic source in the neighbouring lithosphere is obtained by the Elsasser diffusion equation for an elastic lithosphere coupled with a viscous asthenosphere. The results obtained by numerical experiments indicate that the strain regime induced by the Montenegro event in southern Italy is compatible with the tensional strain field observed in this last zone, that the amplitude of the induced strain is significantly higher than that induced by Earth tides and that this amplitude is comparable with the strain perturbation recognized as responsible for <span class="hlt">earthquake</span> triggering. The time delay between the triggering and the induced</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21254893','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21254893"><span>Precursory measure of interoccurrence time associated with large <span class="hlt">earthquakes</span> in the Burridge-Knopoff <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hasumi, Tomohiro</p> <p>2008-11-13</p> <p>We studied the statistical properties of interoccurrence time i.e., time intervals between successive <span class="hlt">earthquakes</span> in the two-dimensional (2D) Burridge-Knopoff (BK) <span class="hlt">model</span>, and have found that these statistics can be classified into three types: the subcritical state, the critical state, and the supercritical state. The survivor function of interoccurrence time is well fitted by the Zipf-Mandelbrot type power law in the subcritical regime. However, the fitting accuracy of this distribution tends to be worse as the system changes from the subcritical state to the supercritical state. Because the critical phase of a fault system in nature changes from the subcritical state to the supercritical state prior to a forthcoming large <span class="hlt">earthquake</span>, we suggest that the fitting accuracy of the survivor distribution can be another precursory measure associated with large <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007Tectp.438...33O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007Tectp.438...33O"><span>Source parameters of intermediate-depth Vrancea (Romania) <span class="hlt">earthquakes</span> from empirical Green's functions <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oth, Adrien; Wenzel, Friedemann; Radulian, Mircea</p> <p>2007-06-01</p> <p>Several source parameters (source dimensions, slip, particle velocity, static and dynamic stress drop) are determined for the moderate-size October 27th, 2004 ( MW = 5.8), and the large August 30th, 1986 ( MW = 7.1) and March 4th, 1977 ( MW = 7.4) Vrancea (Romania) intermediate-depth <span class="hlt">earthquakes</span>. For this purpose, the empirical Green's functions method of Irikura [e.g. Irikura, K. (1983). Semi-Empirical Estimation of Strong Ground Motions during Large <span class="hlt">Earthquakes</span>. Bull. Dis. Prev. Res. Inst., Kyoto Univ., 33, Part 2, No. 298, 63-104., Irikura, K. (1986). Prediction of strong acceleration motions using empirical Green's function, in Proceedings of the 7th Japan <span class="hlt">earthquake</span> engineering symposium, 151-156., Irikura, K. (1999). Techniques for the simulation of strong ground motion and deterministic seismic hazard analysis, in Proceedings of the advanced study course seismotectonic and microzonation techniques in <span class="hlt">earthquake</span> engineering: integrated training in <span class="hlt">earthquake</span> risk reduction practices, Kefallinia, 453-554.] is used to generate synthetic time series from recordings of smaller events (with 4 ≤ MW ≤ 5) in order to estimate several parameters characterizing the so-called strong motion generation area, which is defined as an extended area with homogeneous slip and rise time and, for crustal <span class="hlt">earthquakes</span>, corresponds to an asperity of about 100 bar stress release [Miyake, H., T. Iwata and K. Irikura (2003). Source characterization for broadband ground-motion simulation: Kinematic heterogeneous source <span class="hlt">model</span> and strong motion generation area. Bull. Seism. Soc. Am., 93, 2531-2545.] The parameters are obtained by acceleration envelope and displacement waveform inversion for the 2004 and 1986 events and MSK intensity pattern inversion for the 1977 event using a genetic algorithm. The strong motion recordings of the analyzed Vrancea <span class="hlt">earthquakes</span> as well as the MSK intensity pattern of the 1977 <span class="hlt">earthquake</span> can be well reproduced using relatively small strong motion</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGeo..110....1L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGeo..110....1L"><span>Recurrence interval of the 2008 Mw 7.9 Wenchuan <span class="hlt">earthquake</span> inferred from geodynamic <span class="hlt">modelling</span> stress buildup and release</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Chang; Dong, Peiyu; Shi, Yaolin</p> <p>2017-10-01</p> <p>The destructive 2008 Mw 7.9 Wenchuan <span class="hlt">earthquake</span> ruptured the Longmen Shan (LMS) fault zone and devastated cities in Sichuan province, China. Estimates of the recurrence interval of the large <span class="hlt">earthquake</span> is important to understand the feature of seismic activity and to analyze the seismic hazard in the fault area. In this research we introduce the method of geodynamic <span class="hlt">modelling</span> to estimate the recurrence interval of the Mw7.9 <span class="hlt">earthquake</span> based on the basic physics of <span class="hlt">earthquakes</span>-stress buildup and release on fault. The inter-seismic stress accumulation prior to the 2008 Wenchuan <span class="hlt">earthquake</span> is extracted from our previous study, which developed 3D finite element visco-elastic lithospheric <span class="hlt">model</span> of the LMS fault zone. The co-seismic stress release and the post-seismic stress relaxation of the <span class="hlt">earthquake</span> are simulated through dislocation source <span class="hlt">models</span>. The recurrence interval, which is the duration needed to accumulate the magnitude of the stress drop of the Mw7.9 <span class="hlt">earthquake</span>, is estimated to be about 4200-6500 years. Sensitivities of the estimated recurrence interval relying on <span class="hlt">model</span> dependent parameters, such as the viscosity and slip <span class="hlt">models</span>, are discussed. This research provides a preferred method to estimate recurrence interval of large <span class="hlt">earthquake</span> in fault zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S41A1999S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S41A1999S"><span>Benefits of multidisciplinary collaboration for <span class="hlt">earthquake</span> casualty estimation <span class="hlt">models</span>: recent case studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>So, E.</p> <p>2010-12-01</p> <p><span class="hlt">Earthquake</span> casualty loss estimation, which depends primarily on building-specific casualty rates, has long suffered from a lack of cross-disciplinary collaboration in post-<span class="hlt">earthquake</span> data gathering. An increase in our understanding of what contributes to casualties in <span class="hlt">earthquakes</span> involve coordinated data-gathering efforts amongst disciplines; these are essential for improved global casualty estimation <span class="hlt">models</span>. It is evident from examining past casualty loss <span class="hlt">models</span> and reviewing field data collected from recent events, that generalized casualty rates cannot be applied globally for different building types, even within individual countries. For a particular structure type, regional and topographic building design effects, combined with variable material and workmanship quality all contribute to this multi-variant outcome. In addition, social factors affect building-specific casualty rates, including social status and education levels, and human behaviors in general, in that they modify egress and survivability rates. Without considering complex physical pathways, loss <span class="hlt">models</span> purely based on historic casualty data, or even worse, rates derived from other countries, will be of very limited value. What’s more, as the world’s population, housing stock, and living and cultural environments change, methods of loss <span class="hlt">modeling</span> must accommodate these variables, especially when considering casualties. To truly take advantage of observed <span class="hlt">earthquake</span> losses, not only do damage surveys need better coordination of international and national reconnaissance teams, but these teams must integrate difference areas of expertise including engineering, public health and medicine. Research is needed to find methods to achieve consistent and practical ways of collecting and <span class="hlt">modeling</span> casualties in <span class="hlt">earthquakes</span>. International collaboration will also be necessary to transfer such expertise and resources to the communities in the cities which most need it. Coupling the theories and findings from</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFM.S43B1382H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFM.S43B1382H"><span>3D <span class="hlt">Modeling</span> of <span class="hlt">Earthquakes</span> using Time-Reversal or Adjoint Methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hjorleifsdottir, V.; Liu, Q.; Tromp, J.</p> <p>2006-12-01</p> <p>The availability of global broad-band seismic data has allowed for detailed <span class="hlt">modeling</span> of slip on a fault plane for many recent large <span class="hlt">earthquakes</span>. This is a difficult process involving many trade-offs between <span class="hlt">model</span> parameters. Although the whole waveform contains information about the <span class="hlt">earthquake</span>, most studies focus on limited parts of the time series to extract source information. This is in part to avoid errors from not accurately accounting for 3D structure along the propagation path. By <span class="hlt">modeling</span> <span class="hlt">earthquakes</span> using 3D structure one could use more of the time series to constrain the source process, thereby reducing the trade-offs. Further, the effect of assuming a 1D structure in the source region on source <span class="hlt">models</span> has not been carefully studied, especially for subduction zones where the structure is often very heterogeneous. Traditional inversion techniques require computation of a large Green's function library, which can become very computationally expensive in the case of 3D <span class="hlt">modeling</span>. A 3D time-stepping method would require two simulations for each sub fault, once a location and orientation of the fault plane has been chosen. An alternative would be to use an `adjoint' method, which computes the gradient of the misfit function for a given <span class="hlt">model</span> in only two simulations (Tarantola Geoph.~1984, Tromp et al.~GJI 2005). Combining this with a conjugate gradient method, we can obtain a final <span class="hlt">model</span> from much fewer 3D simulations than by computing the whole Green's function library, reducing the computational cost. In it's simplest form an adjoint method for inverting for source parameters can be viewed as a time-reversal experiment performed with a wave-propagation code (McMechan GJRAS 1982). The recorded seismograms are inserted as simultaneous sources at the location of the receiver and the computed wave field (which we call the adjoint wavefield) is recorded on an array around the <span class="hlt">earthquake</span> location. A special case is the source-scanning or stacking algorithm as used</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8194R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8194R"><span>A new statistical time-dependent <span class="hlt">model</span> of <span class="hlt">earthquake</span> occurrence: failure processes driven by a self-correcting <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rotondi, Renata; Varini, Elisa</p> <p>2016-04-01</p> <p>The long-term recurrence of strong <span class="hlt">earthquakes</span> is often <span class="hlt">modelled</span> by the stationary Poisson process for the sake of simplicity, although renewal and self-correcting point processes (with non-decreasing hazard functions) are more appropriate. Short-term <span class="hlt">models</span> mainly fit <span class="hlt">earthquake</span> clusters due to the tendency of an <span class="hlt">earthquake</span> to trigger other <span class="hlt">earthquakes</span>; in this case, self-exciting point processes with non-increasing hazard are especially suitable. In order to provide a unified framework for analyzing <span class="hlt">earthquake</span> catalogs, Schoenberg and Bolt proposed the SELC (Short-term Exciting Long-term Correcting) <span class="hlt">model</span> (BSSA, 2000) and Varini employed a state-space <span class="hlt">model</span> for estimating the different phases of a seismic cycle (PhD Thesis, 2005). Both attempts are combinations of long- and short-term <span class="hlt">models</span>, but results are not completely satisfactory, due to the different scales at which these <span class="hlt">models</span> appear to operate. In this study, we split a seismic sequence in two groups: the leader events, whose magnitude exceeds a threshold magnitude, and the remaining ones considered as subordinate events. The leader events are assumed to follow a well-known self-correcting point process named stress release <span class="hlt">model</span> (Vere-Jones, J. Phys. Earth, 1978; Bebbington & Harte, GJI, 2003, Varini & Rotondi, Env. Ecol. Stat., 2015). In the interval between two subsequent leader events, subordinate events are expected to cluster at the beginning (aftershocks) and at the end (foreshocks) of that interval; hence, they are <span class="hlt">modeled</span> by a failure processes that allows bathtub-shaped hazard function. In particular, we have examined the generalized Weibull distributions, a large family that contains distributions with different bathtub-shaped hazard as well as the standard Weibull distribution (Lai, Springer, 2014). The <span class="hlt">model</span> is fitted to a dataset of Italian historical <span class="hlt">earthquakes</span> and the results of Bayesian inference are shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21076231','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21076231"><span>Interoccurrence time statistics in the two-dimensional Burridge-Knopoff <span class="hlt">earthquake</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hasumi, Tomohiro</p> <p>2007-08-15</p> <p>We have numerically investigated statistical properties of the so-called interoccurrence time or the waiting time, i.e., the time interval between successive <span class="hlt">earthquakes</span>, based on the two-dimensional (2D) spring-block (Burridge-Knopoff) <span class="hlt">model</span>, selecting the velocity-weakening property as the constitutive friction law. The statistical properties of frequency distribution and the cumulative distribution of the interoccurrence time are discussed by tuning the dynamical parameters, namely, a stiffness and frictional property of a fault. We optimize these <span class="hlt">model</span> parameters to reproduce the interoccurrence time statistics in nature; the frequency and cumulative distribution can be described by the power law and Zipf-Mandelbrot type power law, respectively. In an optimal case, the b value of the Gutenberg-Richter law and the ratio of wave propagation velocity are in agreement with those derived from real <span class="hlt">earthquakes</span>. As the threshold of magnitude is increased, the interoccurrence time distribution tends to follow an exponential distribution. Hence it is suggested that a temporal sequence of <span class="hlt">earthquakes</span>, aside from small-magnitude events, is a Poisson process, which is observed in nature. We found that the interoccurrence time statistics derived from the 2D BK (original) <span class="hlt">model</span> can efficiently reproduce that of real <span class="hlt">earthquakes</span>, so that the <span class="hlt">model</span> can be recognized as a realistic one in view of interoccurrence time statistics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70013784','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70013784"><span>Forecast <span class="hlt">model</span> for great <span class="hlt">earthquakes</span> at the Nankai Trough 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>Stuart, W.D.</p> <p>1988-01-01</p> <p>An <span class="hlt">earthquake</span> instability <span class="hlt">model</span> is formulated for recurring great <span class="hlt">earthquakes</span> at the Nankai Trough subduction zone in southwest Japan. The <span class="hlt">model</span> is quasistatic, two-dimensional, and has a displacement and velocity dependent constitutive law applied at the fault plane. A constant rate of fault slip at depth represents forcing due to relative motion of the Philippine Sea and Eurasian plates. The <span class="hlt">model</span> simulates fault slip and stress for all parts of repeated <span class="hlt">earthquake</span> cycles, including post-, inter-, pre- and coseismic stages. Calculated ground uplift is in agreement with most of the main features of elevation changes observed before and after the M=8.1 1946 Nankaido <span class="hlt">earthquake</span>. In <span class="hlt">model</span> simulations, accelerating fault slip has two time-scales. The first time-scale is several years long and is interpreted as an intermediate-term precursor. The second time-scale is a few days long and is interpreted as a short-term precursor. Accelerating fault slip on both time-scales causes anomalous elevation changes of the ground surface over the fault plane of 100 mm or less within 50 km of the fault trace. ?? 1988 Birkha??user Verlag.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17393560','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17393560"><span>Neural network <span class="hlt">models</span> for <span class="hlt">earthquake</span> magnitude prediction using multiple seismicity indicators.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Panakkat, Ashif; Adeli, Hojjat</p> <p>2007-02-01</p> <p>Neural networks are investigated for predicting the magnitude of the largest seismic event in the following month based on the analysis of eight mathematically computed parameters known as seismicity indicators. The indicators are selected based on the Gutenberg-Richter and characteristic <span class="hlt">earthquake</span> magnitude distribution and also on the conclusions drawn by recent <span class="hlt">earthquake</span> prediction studies. Since there is no known established mathematical or even empirical relationship between these indicators and the location and magnitude of a succeeding <span class="hlt">earthquake</span> in a particular time window, the problem is <span class="hlt">modeled</span> using three different neural networks: a feed-forward Levenberg-Marquardt backpropagation (LMBP) neural network, a recurrent neural network, and a radial basis function (RBF) neural network. Prediction accuracies of the <span class="hlt">models</span> are evaluated using four different statistical measures: the probability of detection, the false alarm ratio, the frequency bias, and the true skill score or R score. The <span class="hlt">models</span> are trained and tested using data for two seismically different regions: Southern California and the San Francisco bay region. Overall the recurrent neural network <span class="hlt">model</span> yields the best prediction accuracies compared with LMBP and RBF networks. While at the present <span class="hlt">earthquake</span> prediction cannot be made with a high degree of certainty this research provides a scientific approach for evaluating the short-term seismic hazard potential of a region.</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><span class="hlt">Modeling</span> 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 recurrence 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 recurrence 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) <span class="hlt">model</span>, and use the <span class="hlt">model</span> 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 <span class="hlt">model</span> mimics the slipping of deep fault patches by a spring-drugged block slider with both brittle and ductile friction components. We use the BDF <span class="hlt">model</span> 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('http://adsabs.harvard.edu/abs/2013PApGe.170.1567S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PApGe.170.1567S"><span>Tsunami Source of the 2010 Mentawai, Indonesia <span class="hlt">Earthquake</span> Inferred from Tsunami Field Survey and Waveform <span class="hlt">Modeling</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; Nishimura, Yuichi; Putra, Purna Sulastya; Gusman, Aditya Riadi; Sunendar, Haris; Fujii, Yushiro; Tanioka, Yuichiro; Latief, Hamzah; Yulianto, Eko</p> <p>2013-09-01</p> <p>The 2010 Mentawai <span class="hlt">earthquake</span> (magnitude 7.7) generated a destructive tsunami that caused more than 500 casualties in the Mentawai Islands, west of Sumatra, Indonesia. Seismological analyses indicate that this <span class="hlt">earthquake</span> was an unusual "tsunami <span class="hlt">earthquake</span>," which produces much larger tsunamis than expected from the seismic magnitude. We carried out a field survey to measure tsunami heights and inundation distances, an inversion of tsunami waveforms to estimate the slip distribution on the fault, and inundation <span class="hlt">modeling</span> to compare the measured and simulated tsunami heights. The measured tsunami heights at eight locations on the west coasts of North and South Pagai Island ranged from 2.5 to 9.3 m, but were mostly in the 4-7 m range. At three villages, the tsunami inundation extended more than 300 m. Interviews of local residents indicated that the <span class="hlt">earthquake</span> ground shaking was less intense than during previous large <span class="hlt">earthquakes</span> and did not cause any damage. Inversion of tsunami waveforms recorded at nine coastal tide gauges, a nearby GPS buoy, and a DART station indicated a large slip (maximum 6.1 m) on a shallower part of the fault near the trench axis, a distribution similar to other tsunami <span class="hlt">earthquakes</span>. The total seismic moment estimated from tsunami waveform inversion was 1.0 × 1021 Nm, which corresponded to Mw 7.9. Computed coastal tsunami heights from this tsunami source <span class="hlt">model</span> using linear equations are similar to the measured tsunami heights. The inundation heights computed by using detailed bathymetry and topography data and nonlinear equations including inundation were smaller than the measured ones. This may have been partly due to the limited resolution and accuracy of publically available bathymetry and topography data. One-dimensional run-up computations using our surveyed topography profiles showed that the computed heights were roughly similar to the measured ones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.S33A2507F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.S33A2507F"><span>Stochastic <span class="hlt">modelling</span> of a large subduction interface <span class="hlt">earthquake</span> in Wellington, New Zealand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Francois-Holden, C.; Zhao, J.</p> <p>2012-12-01</p> <p>The Wellington region, home of New Zealand's capital city, is cut by a number of major right-lateral strike slip faults, and is underlain by the currently locked west-dipping subduction interface between the down going Pacific Plate, and the over-riding Australian Plate. A potential cause of significant <span class="hlt">earthquake</span> loss in the Wellington region is a large magnitude (perhaps 8+) "subduction <span class="hlt">earthquake</span>" on the Australia-Pacific plate interface, which lies ~23 km beneath Wellington City. "It's Our Fault" is a project involving a comprehensive study of Wellington's <span class="hlt">earthquake</span> risk. Its objective is to position Wellington city to become more resilient, through an encompassing study of the likelihood of large <span class="hlt">earthquakes</span>, and the effects and impacts of these <span class="hlt">earthquakes</span> on humans and the built environment. As part of the "It's Our Fault" project, we are working on estimating ground motions from potential large plate boundary <span class="hlt">earthquakes</span>. We present the latest results on ground motion simulations in terms of response spectra and acceleration time histories. First we characterise the potential interface rupture area based on previous geodetically-derived estimates interface of slip deficit. Then, we entertain a suitable range of source parameters, including various rupture areas, moment magnitudes, stress drops, slip distributions and rupture propagation directions. Our comprehensive study also includes simulations from historical large world subduction events translated into the New Zealand subduction context, such as the 2003 M8.3 Tokachi-Oki Japan <span class="hlt">earthquake</span> and the M8.8 2010 Chili <span class="hlt">earthquake</span>. To <span class="hlt">model</span> synthetic seismograms and the corresponding response spectra we employed the EXSIM code developed by Atkinson et al. (2009), with a regional attenuation <span class="hlt">model</span> based on the 3D attenuation <span class="hlt">model</span> for the lower North-Island which has been developed by Eberhart-Phillips et al. (2005). The resulting rupture scenarios all produce long duration shaking, and peak ground</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.T53C2141Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.T53C2141Z"><span><span class="hlt">Modeling</span> dynamic processes of the Wenchuan <span class="hlt">earthquake</span> with finite element method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhu, S.; Zhang, P.</p> <p>2010-12-01</p> <p>The sudden and unexpected Wenchuan <span class="hlt">earthquake</span> (Mw=7.9) occurred on the Longmen Shan Fault, causing a large number of casualties and huge property loss. As one of the most devastating <span class="hlt">earthquakes</span> in China, the 2008 Wenchuan <span class="hlt">earthquake</span> occurred on imbricate, high-angle listric reverse faults. The faults dip ~70° above 15 km deep, become 30° to 40° below ~15 km deep, and presumably root into sub-horizontal brittle-ductile transition zone below about 22±2 km deep. In this paper we use visco-elastic finite element method to simulate co-seismic deformation and stress change, and recurrence of major <span class="hlt">earthquakes</span> associated with the high-angle listric reverse fault. Our <span class="hlt">modeling</span> shows that changes of co-seismic equivalent stress mainly occurs in the vicinity of the seismogenic fault, especially hanging wall of the fault in the depth range above 12 km. <span class="hlt">Modeled</span> co-seismic slip distribution and <span class="hlt">modeled</span> average recurrent interval corroborate with geological, geodetic and seismological observations. We <span class="hlt">modeled</span> 250,000 years slip history of the fault slip. The result shows that minor slips, that obey slip-predictable <span class="hlt">model</span>, take places on 30°-40° dipping fault plane at depth below 15 km. When the isotropic stress accumulation on the gentle fault reaches the critical level, the entire gently dipping fault ruptures to form a large slip. The large slips on the gently dipping fault comply with time-predictable <span class="hlt">model</span> of recurrences. These larger slips on the gently dipping fault occur simultaneously with slips on the steeply dipping fault, and might have triggered slips on the steeply dipping fault to form great events such as the 2008 Wenchuan <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CompM.tmp..112G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CompM.tmp..112G"><span>The spectral cell method in nonlinear <span class="hlt">earthquake</span> <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Giraldo, Daniel; Restrepo, Doriam</p> <p>2017-08-01</p> <p>This study examines the applicability of the spectral cell method (SCM) to compute the nonlinear <span class="hlt">earthquake</span> response of complex basins. SCM combines fictitious-domain concepts with the spectral-version of the finite element method to solve the wave equations in heterogeneous geophysical domains. Nonlinear behavior is considered by implementing the Mohr-Coulomb and Drucker-Prager yielding criteria. We illustrate the performance of SCM with numerical examples of nonlinear basins exhibiting physically and computationally challenging conditions. The numerical experiments are benchmarked with results from overkill solutions, and using MIDAS GTS NX, a finite element software for geotechnical applications. Our findings show good agreement between the two sets of results. Traditional spectral elements implementations allow points per wavelength as low as PPW = 4.5 for high-order polynomials. Our findings show that in the presence of nonlinearity, high-order polynomials (p ≥ 3 ) require mesh resolutions above of PPW ≥ 10 to ensure displacement errors below 10%.</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://adsabs.harvard.edu/abs/2015AGUFMNH13B1919K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH13B1919K"><span>Planning a Preliminary program for <span class="hlt">Earthquake</span> Loss Estimation and Emergency Operation by Three-dimensional Structural <span class="hlt">Model</span> of 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>Ke, M. C.</p> <p>2015-12-01</p> <p>Large scale <span class="hlt">earthquakes</span> often cause serious economic losses and a lot of deaths. Because the seismic magnitude, the occurring time and the occurring location of <span class="hlt">earthquakes</span> are still unable to predict now. The pre-disaster risk <span class="hlt">modeling</span> and post-disaster operation are really important works of reducing <span class="hlt">earthquake</span> damages. In order to understanding disaster risk of <span class="hlt">earthquakes</span>, people usually use the technology of <span class="hlt">Earthquake</span> simulation to build the <span class="hlt">earthquake</span> scenarios. Therefore, Point source, fault line source and fault plane source are the <span class="hlt">models</span> which often are used as a seismic source of scenarios. The assessment results made from different <span class="hlt">models</span> used on risk assessment and emergency operation of <span class="hlt">earthquakes</span> are well, but the accuracy of the assessment results could still be upgrade. This program invites experts and scholars from Taiwan University, National Central University, and National Cheng Kung University, and tries using historical records of <span class="hlt">earthquakes</span>, geological data and geophysical data to build underground three-dimensional structure planes of active faults. It is a purpose to replace projection fault planes by underground fault planes as similar true. The analysis accuracy of <span class="hlt">earthquake</span> prevention efforts can be upgraded by this database. Then these three-dimensional data will be applied to different stages of disaster prevention. For pre-disaster, results of <span class="hlt">earthquake</span> risk analysis obtained by the three-dimensional data of the fault plane are closer to real damage. For disaster, three-dimensional data of the fault plane can be help to speculate that aftershocks distributed and serious damage area. The program has been used 14 geological profiles to build the three dimensional data of Hsinchu fault and HisnCheng faults in 2015. Other active faults will be completed in 2018 and be actually applied on <span class="hlt">earthquake</span> disaster prevention.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014JGRB..119.8089S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014JGRB..119.8089S"><span>A friction to flow constitutive law and its application to a 2-D <span class="hlt">modeling</span> 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>Shimamoto, Toshihiko; Noda, Hiroyuki</p> <p>2014-11-01</p> <p>Establishment of a constitutive law from friction to high-temperature plastic flow has long been a challenging task for solving problems such as <span class="hlt">modeling</span> <span class="hlt">earthquakes</span> and plate interactions. Here we propose an empirical constitutive law that describes this transitional behavior using only friction and flow parameters, with good agreements with experimental data on halite shear zones. The law predicts steady state and transient behaviors, including the dependence of the shear resistance of fault on slip rate, effective normal stress, and temperature. It also predicts a change in velocity weakening to velocity strengthening with increasing temperature, similar to the changes recognized for quartz and granite gouge under hydrothermal conditions. A slight deviation from the steady state friction law due to the involvement of plastic deformation can cause a large change in the velocity dependence. We solved seismic cycles of a fault across the lithosphere with the law using a 2-D spectral boundary integral equation method, revealing dynamic rupture extending into the aseismic zone and rich evolution of interseismic creep including slow slip prior to <span class="hlt">earthquakes</span>. Seismic slip followed by creep is consistent with natural pseudotachylytes overprinted with mylonitic deformation. Overall fault behaviors during <span class="hlt">earthquake</span> cycles are insensitive to transient flow parameters. The friction-to-flow law merges "Christmas tree" strength profiles of the lithosphere and rate dependency fault <span class="hlt">models</span> used for <span class="hlt">earthquake</span> <span class="hlt">modeling</span> on a unified basis. Strength profiles were drawn assuming a strain rate for the flow regime, but we emphasize that stress distribution evolves reflecting the fault behavior. A fault zone <span class="hlt">model</span> was updated based on the <span class="hlt">earthquake</span> <span class="hlt">modeling</span>.</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> Rate <span class="hlt">Models</span> 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> rates 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 <span class="hlt">model</span> of mainshock occurrence. To help society cope with rapidly evolving seismicity, the USGS is developing one-year hazard <span class="hlt">models</span> 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> rates 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 rate to forecast the next year's seismicity rate. However, in places such as northern Oklahoma the rates vary so rapidly over time that a simple linear extrapolation does not accurately forecast the future, even when the variability in the rates is <span class="hlt">modeled</span> with simulations based on an Epidemic-Type Aftershock Sequence (ETAS) <span class="hlt">model</span> (Ogata, JASA, 1988) to account for <span class="hlt">earthquake</span> clustering. Instead of relying on a fixed time period for rate estimation, we explore another way to determine when the <span class="hlt">earthquake</span> rate should be updated. This approach could also objectively identify new areas where the induced seismicity hazard <span class="hlt">model</span> should be applied. We will estimate the background seismicity rate 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 rate parameters in each zone. The full seismicity rate, with uncertainties, can then be estimated using ETAS simulations and changes in rate 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('http://pubs.er.usgs.gov/publication/70023066','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70023066"><span>Viscoelastic shear zone <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">model</span> predicts that sufficiently long after initiation of the system, (1) average fault-parallel velocity at any point is the average slip rate of that side of the fault and (2) far-field velocities equal the same constant rate. Because of the sensitivity to the mechanical properties of the schizosphere-plastosphere system (i.e., elastic layer thickness, plastosphere viscosity), this <span class="hlt">model</span> 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 <span class="hlt">model</span> 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 <span class="hlt">model</span>. These differences are magnified as plastosphere viscosity is reduced or as the recurrence 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('http://adsabs.harvard.edu/abs/2017JPhB...50j5101C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JPhB...50j5101C"><span>Effects of parity <span class="hlt">nonconservation</span> in a molecule of oxygen</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chubukov, D. V.; Skripnikov, L. V.; Andreev, O. Yu; Labzowsky, L. N.; Plunien, G.</p> <p>2017-05-01</p> <p>This paper is devoted to the calculation of parity <span class="hlt">nonconserving</span> (PNC) effects in the diatomic homonuclear molecule of oxygen O2. For this purpose the magnetic dipole transition b{}1{{{Σ }}}g+≤ftarrow X{}3{{{Σ }}}g- was considered. It was believed that the weak electron-electron interaction prevails over the weak interaction of electrons with nuclei in this case. This idea appeared not to be justified for molecular oxygen. As it turns out from our calculations, the parity <span class="hlt">nonconservation</span> degree for the weak electron-nucleus interaction is of the order {{ P }}{{eN}}=1.4\\cdot {10}-11 and for the weak electron-electron interaction is by two orders smaller {{ P }}{{ee}}=1.1\\cdot {10}-13. Nevertheless, a PNC experiment for the observation of the weak electron-nucleus interaction looks sufficiently feasible (previously, such experiments were carried out only with atoms).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PhRvA..96a2516F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PhRvA..96a2516F"><span>Effect of nuclear quadrupole moments on parity <span class="hlt">nonconservation</span> in atoms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Flambaum, V. V.; Dzuba, V. A.; Harabati, C.</p> <p>2017-07-01</p> <p>Nuclei with spin I ≥1 have a weak quadrupole moment which leads to tensor contribution to the parity <span class="hlt">nonconserving</span> interaction between nuclei and electrons. We calculate this contribution for atoms of current experiment interest Yb+, Fr, and Ra+. We have also performed order of magnitude estimates and found strong enhancement of the weak quadrupole effects due to the close levels of opposite parity in many lanthanoids (e.g., Nd, Gd, Dy, Ho, Er, Pr, Sm) and Ra. Another possibility is to measure the parity-<span class="hlt">nonconservation</span> (PNC) transitions between the hyperfine components of the ground state of Bi. Since nuclear weak charge is dominated by neutrons this opens a way of measuring quadrupole moments of neutron distribution in nuclei.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70190039','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70190039"><span>A long-term <span class="hlt">earthquake</span> rate <span class="hlt">model</span> 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> rate <span class="hlt">model</span> 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 <span class="hlt">models</span> 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 <span class="hlt">models</span>, 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 <span class="hlt">models</span> 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 rate <span class="hlt">model</span> with uniform rates in all cells. In this regard, fixed smoothing <span class="hlt">models</span> perform better than adaptive smoothing <span class="hlt">models</span>. The preferred <span class="hlt">model</span> of this study is the adaptive smoothed seismicity <span class="hlt">model</span>, 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 rate <span class="hlt">model</span> delineates 12 regions where the annual rate 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 rates from fixed smoothed seismicity <span class="hlt">models</span>, with rate increases of up to a factor of 10 near clusters of high seismic activity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028804','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028804"><span>Three-dimensional compressional wavespeed <span class="hlt">model</span>, <span class="hlt">earthquake</span> relocations, and focal mechanisms for the Parkfield, California, region</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Thurber, C.; Zhang, H.; Waldhauser, F.; Hardebeck, J.; Michael, A.; Eberhart-Phillips, D.</p> <p>2006-01-01</p> <p>We present a new three-dimensional (3D) compressional vvavespeed (V p) <span class="hlt">model</span> for the Parkfield region, taking advantage of the recent seismicity associated with the 2003 San Simeon and 2004 Parkfield <span class="hlt">earthquake</span> sequences to provide increased <span class="hlt">model</span> resolution compared to the work of Eberhart-Phillips and Michael (1993) (EPM93). Taking the EPM93 3D <span class="hlt">model</span> as our starting <span class="hlt">model</span>, we invert the arrival-time data from about 2100 <span class="hlt">earthquakes</span> and 250 shots recorded on both permanent network and temporary stations in a region 130 km northeast-southwest by 120 km northwest-southeast. We include catalog picks and cross-correlation and catalog differential times in the inversion, using the double-difference tomography method of Zhang and Thurber (2003). The principal Vp features reported by EPM93 and Michelini and McEvilly (1991) are recovered, but with locally improved resolution along the San Andreas Fault (SAF) and near the active-source profiles. We image the previously identified strong wavespeed contrast (faster on the southwest side) across most of the length of the SAF, and we also improve the image of a high Vp body on the northeast side of the fault reported by EPM93. This narrow body is at about 5- to 12-km depth and extends approximately from the locked section of the SAP to the town of Parkfield. The footwall of the thrust fault responsible for the 1983 Coalinga <span class="hlt">earthquake</span> is imaged as a northeast-dipping high wavespeed body. In between, relatively low wavespeeds (<5 km/sec) extend to as much as 10-km depth. We use this <span class="hlt">model</span> to derive absolute locations for about 16,000 <span class="hlt">earthquakes</span> from 1966 to 2005 and high-precision double-difference locations for 9,000 <span class="hlt">earthquakes</span> from 1984 to 2005, and also to determine focal mechanisms for 446 <span class="hlt">earthquakes</span>. These <span class="hlt">earthquake</span> locations and mechanisms show that the seismogenic fault is a simple planar structure. The aftershock sequence of the 2004 mainshock concentrates into the same structures defined by the pre-2004 seismicity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984PhLB..142....1A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984PhLB..142....1A"><span>Parity <span class="hlt">nonconserving</span> spin rotation in weak neutron-proton scattering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Avishai, Y.</p> <p>1984-07-01</p> <p>Parity <span class="hlt">nonconservation</span> in weak n-p scattering is studied at threshold wehre neutron spin rotation might occur. We use the DDH weak NN force and a separable form with S, P and D partial waves in the strong NN interaction. The contribution of various spin-isospin components to the weak NN scattering amplitude is evaluated and the spin rotation angle is found to be -2.35 × 10 -9 rad/cm. The sources of possible errors are indicated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S11A1006K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S11A1006K"><span>Analysis of the M=7.2 1992 Cape Mendocino <span class="hlt">Earthquake</span> with Kinematic Source <span class="hlt">Models</span> and Empirical Green's Functions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kane, D. L.; Hutchings, L. J.</p> <p>2004-12-01</p> <p>The M=7.2 Cape Mendocino <span class="hlt">earthquake</span> occurred on April 25, 1992 and is potentially the first subduction zone <span class="hlt">earthquake</span> recorded in the Mendocino Triple Junction region. We utilize recordings of weak motion events as empirical Green's functions to constrain the propagation path effects of the <span class="hlt">earthquakes</span> in forward kinematic <span class="hlt">modeling</span>. Using constraints based on the 1992 event, we create kinematic source <span class="hlt">models</span> based upon physical parameters of fault rupture and generate a suite of synthetic accelerograms to identify potential fault rupture characteristics of the actual <span class="hlt">earthquake</span>. The precise fault for the 1992 <span class="hlt">earthquake</span> is not known, so we confine the calculations to a small source volume where the <span class="hlt">earthquake</span> likely occurred and run 100 scenario <span class="hlt">earthquakes</span>. This also provides a test of a physically-based methodology to predict the range of ground motion that may occur from a particular magnitude <span class="hlt">earthquake</span> along a specific fault or within a specific source volume. We test whether the actual ground motion recordings fall within the range predicted. We also test the hypothesis that some of the synthesized records will match those observed, and we make the assumption that the source <span class="hlt">models</span> for these records are close to what actually occurred. This work was performed under the auspices of the U.S. Department of Energy by the University of California, Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.U13E2088D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.U13E2088D"><span>Visualizing the 2009 Samoan and Sumatran <span class="hlt">Earthquakes</span> using Google Earth-based COLLADA <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>de Paor, D. G.; Brooks, W. D.; Dordevic, M.; Ranasinghe, N. R.; Wild, S. C.</p> <p>2009-12-01</p> <p><span class="hlt">Earthquake</span> hazards are generally analyzed by a combination of graphical focal mechanism or centroid moment tensor solutions (aka geophysical beach balls), contoured fault plane maps, and shake maps or tsunami damage surveys. In regions of complex micro-plate tectonics, it can be difficult to visualize spatial and temporal relations among <span class="hlt">earthquakes</span>, aftershocks, and associated tectonic and volcanic structures using two-dimensional maps and cross sections alone. Developing the techniques originally described by D.G. De Paor & N.R. Williams (EOS Trans. AGU S53E-05, 2006), we can view the plate tectonic setting, geophysical parameters, and societal consequences of the 2009 Samoan and Sumatran <span class="hlt">earthquakes</span> on the Google Earth virtual globe. We use xml-based COLLADA <span class="hlt">models</span> to represent the subsurface structure and standard KML to overlay map data on the digital terrain <span class="hlt">model</span>. Unlike traditional geophysical beach ball figures, our <span class="hlt">models</span> are three dimensional and located at correct depth, and they optionally show nodal planes which are useful in relating the orientation of one <span class="hlt">earthquake</span> to the hypo-centers of its neighbors. With the aid of the new Google Earth application program interface (GE API), we can use web page-based Javascript controls to lift structural <span class="hlt">models</span> from the subsurface in Google Earth and generate serial sections along strike. Finally, we use the built-in features of the Google Earth web browser plug-in to create a virtual tour of damage sites with hyperlinks to web-based field reports. These virtual globe visualizations may help complement existing KML and HTML resources of the USGS <span class="hlt">Earthquake</span> Hazards Program and The Global CMT Project.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NHESS..17.1521R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NHESS..17.1521R"><span>Rapid post-<span class="hlt">earthquake</span> <span class="hlt">modelling</span> of coseismic landslide intensity and distribution for emergency response decision support</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Robinson, Tom R.; Rosser, Nicholas J.; Densmore, Alexander L.; Williams, Jack G.; Kincey, Mark E.; Benjamin, Jessica; Bell, Heather J. A.</p> <p>2017-09-01</p> <p>Current methods to identify coseismic landslides immediately after an <span class="hlt">earthquake</span> using optical imagery are too slow to effectively inform emergency response activities. Issues with cloud cover, data collection and processing, and manual landslide identification mean even the most rapid mapping exercises are often incomplete when the emergency response ends. In this study, we demonstrate how traditional empirical methods for <span class="hlt">modelling</span> the total distribution and relative intensity (in terms of point density) of coseismic landsliding can be successfully undertaken in the hours and days immediately after an <span class="hlt">earthquake</span>, allowing the results to effectively inform stakeholders during the response. The method uses fuzzy logic in a GIS (Geographic Information Systems) to quickly assess and identify the location-specific relationships between predisposing factors and landslide occurrence during the <span class="hlt">earthquake</span>, based on small initial samples of identified landslides. We show that this approach can accurately <span class="hlt">model</span> both the spatial pattern and the number density of landsliding from the event based on just several hundred mapped landslides, provided they have sufficiently wide spatial coverage, improving upon previous methods. This suggests that systematic high-fidelity mapping of landslides following an <span class="hlt">earthquake</span> is not necessary for informing rapid <span class="hlt">modelling</span> attempts. Instead, mapping should focus on rapid sampling from the entire affected area to generate results that can inform the <span class="hlt">modelling</span>. This method is therefore suited to conditions in which imagery is affected by partial cloud cover or in which the total number of landslides is so large that mapping requires significant time to complete. The method therefore has the potential to provide a quick assessment of landslide hazard after an <span class="hlt">earthquake</span> and may therefore inform emergency operations more effectively compared to current practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://earthquake.usgs.gov/resources/software/slope_perf.php','USGSPUBS'); return false;" href="http://earthquake.usgs.gov/resources/software/slope_perf.php"><span>Java Programs for Using Newmark's Method and Simplified Decoupled Analysis to <span class="hlt">Model</span> Slope Performance During <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>Jibson, Randall W.; Jibson, Matthew W.</p> <p>2003-01-01</p> <p>Landslides typically cause a large proportion of <span class="hlt">earthquake</span> damage, and the ability to predict slope performance during <span class="hlt">earthquakes</span> is important for many types of seismic-hazard analysis and for the design of engineered slopes. Newmark's method for <span class="hlt">modeling</span> a landslide as a rigid-plastic block sliding on an inclined plane provides a useful method for predicting approximate landslide displacements. Newmark's method estimates the displacement of a potential landslide block as it is subjected to <span class="hlt">earthquake</span> shaking from a specific strong-motion record (<span class="hlt">earthquake</span> acceleration-time history). A modification of Newmark's method, decoupled analysis, allows <span class="hlt">modeling</span> landslides that are not assumed to be rigid blocks. This open-file report is available on CD-ROM and contains Java programs intended to facilitate performing both rigorous and simplified Newmark sliding-block analysis and a simplified <span class="hlt">model</span> of decoupled analysis. For rigorous analysis, 2160 strong-motion records from 29 <span class="hlt">earthquakes</span> are included along with a search interface for selecting records based on a wide variety of record properties. Utilities are available that allow users to add their own records to the program and use them for conducting Newmark analyses. Also included is a document containing detailed information about how to use Newmark's method to <span class="hlt">model</span> dynamic slope performance. This program will run on any platform that supports the Java Runtime Environment (JRE) version 1.3, including Windows, Mac OSX, Linux, Solaris, etc. A minimum of 64 MB of available RAM is needed, and the fully installed program requires 400 MB of disk space.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.3609D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.3609D"><span>Collective properties of injection-induced <span class="hlt">earthquake</span> sequences: 1. <span class="hlt">Model</span> description and directivity bias</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dempsey, David; Suckale, Jenny</p> <p>2016-05-01</p> <p>Induced seismicity is of increasing concern for oil and gas, geothermal, and carbon sequestration operations, with several M > 5 events triggered in recent years. <span class="hlt">Modeling</span> plays an important role in understanding the causes of this seismicity and in constraining seismic hazard. Here we study the collective properties of induced <span class="hlt">earthquake</span> sequences and the physics underpinning them. In this first paper of a two-part series, we focus on the directivity ratio, which quantifies whether fault rupture is dominated by one (unilateral) or two (bilateral) propagating fronts. In a second paper, we focus on the spatiotemporal and magnitude-frequency distributions of induced seismicity. We develop a <span class="hlt">model</span> that couples a fracture mechanics description of 1-D fault rupture with fractal stress heterogeneity and the evolving pore pressure distribution around an injection well that triggers <span class="hlt">earthquakes</span>. The extent of fault rupture is calculated from the equations of motion for two tips of an expanding crack centered at the <span class="hlt">earthquake</span> hypocenter. Under tectonic loading conditions, our <span class="hlt">model</span> exhibits a preference for unilateral rupture and a normal distribution of hypocenter locations, two features that are consistent with seismological observations. On the other hand, catalogs of induced events when injection occurs directly onto a fault exhibit a bias toward ruptures that propagate toward the injection well. This bias is due to relatively favorable conditions for rupture that exist within the high-pressure plume. The strength of the directivity bias depends on a number of factors including the style of pressure buildup, the proximity of the fault to failure and event magnitude. For injection off a fault that triggers <span class="hlt">earthquakes</span>, the <span class="hlt">modeled</span> directivity bias is small and may be too weak for practical detection. For two hypothetical injection scenarios, we estimate the number of <span class="hlt">earthquake</span> observations required to detect directivity bias.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70182571','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70182571"><span><span class="hlt">Earthquake</span> catalogs for the 2017 Central and Eastern U.S. short-term seismic hazard <span class="hlt">model</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>Mueller, Charles S.</p> <p>2017-01-01</p> <p>The U. S. Geological Survey (USGS) makes long-term seismic hazard forecasts that are used in building codes. The hazard <span class="hlt">models</span> usually consider only natural seismicity; non-tectonic (man-made) <span class="hlt">earthquakes</span> are excluded because they are transitory or too small. In the past decade, however, thousands of <span class="hlt">earthquakes</span> related to underground fluid injection have occurred in the central and eastern U.S. (CEUS), and some have caused damage.  In response, the USGS is now also making short-term forecasts that account for the hazard from these induced <span class="hlt">earthquakes</span>. Seismicity statistics are analyzed to develop recurrence <span class="hlt">models</span>, accounting for catalog completeness. In the USGS hazard <span class="hlt">modeling</span> methodology, <span class="hlt">earthquakes</span> are counted on a map grid, recurrence <span class="hlt">models</span> are applied to estimate the rates of future <span class="hlt">earthquakes</span> in each grid cell, and these rates are combined with maximum-magnitude <span class="hlt">models</span> and ground-motion <span class="hlt">models</span> to compute the hazard The USGS published a forecast for the years 2016 and 2017.Here, we document the development of the seismicity catalogs for the 2017 CEUS short-term hazard <span class="hlt">model</span>.  A uniform <span class="hlt">earthquake</span> catalog is assembled by combining and winnowing pre-existing source catalogs. The initial, final, and supporting <span class="hlt">earthquake</span> catalogs are made available here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.U51B0031K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.U51B0031K"><span>Mega-asperity <span class="hlt">model</span> for the 2011 Tohoku-Oki <span class="hlt">earthquake</span>, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kumagai, H.; Pulido Hernandez, N. E.; Fukuyama, E.; Aoi, S.</p> <p>2011-12-01</p> <p>We performed moment tensor inversion of the 2011 Mw 9.0 Tohoku-Oki <span class="hlt">earthquake</span> using regional seismic waveforms, which indicates that the <span class="hlt">earthquake</span> can be approximated by a point source. We used strong-motion seismograms from a nationwide broadband seismic network of the F-net installed and operated by the National Research Institute for Earth Science and Disaster Prevention (NIED). At each F-net station, a velocity-type strong-motion seismometer is installed at the end of a 30-50 m long vault to record strong motions up to +-2 m/s. We selected five F-net stations with the hypocentral distances more than several hundred kilometers. We used a waveform inversion method that assumes a double-couple focal mechanism for a point source [Nakano et al., 2008, GJI]. Our inversion using the strong-motion seismograms band-pass filtered between 0.006 and 0.02 Hz indicates that the best-fit source location was obtained at 38.25 N, 143.25 E at a depth of 30 km, at which the normalized residual was 0.13. The estimated mechanism and moment magnitude (Mw = 9.0) are consistent with those estimated from global broadband seismographic network data by the global CMT project and the National <span class="hlt">Earthquake</span> Information Center (NEIC) of the U.S. Geological Survey. We fitted the omega-square <span class="hlt">model</span> to amplitude spectra of observed vertical displacement seismograms, which resulted in the corner frequency of around 0.017 Hz. This implies average slip of roughly 70 m over a circular fault with radius of 70 km. These results suggest that a strongly localized asperity (mega asperity) was ruptured during the <span class="hlt">earthquake</span>. For the northeastern Japan subduction zone, where the old Pacific Sea plate subducts along the Japan Trench, the seismic coupling was believed to be very small. The occurrence of the mega <span class="hlt">earthquake</span> is apparently not compatible with weak seismic coupling. However, as suggested by Scholz and Small [1997, Geology], the subduction of a large seamount increases the normal stress across</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PEPI..233...41L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PEPI..233...41L"><span>Source <span class="hlt">models</span> of great <span class="hlt">earthquakes</span> from ultra low-frequency normal mode data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lentas, K.; Ferreira, A. M. G.; Clévédé, E.; Roch, J.</p> <p>2014-08-01</p> <p>We present a new <span class="hlt">earthquake</span> source inversion technique based on normal mode data for the simultaneous determination of the rupture duration, length and moment tensor of large <span class="hlt">earthquakes</span> with unilateral rupture. We use ultra low-frequency (f <1 mHz) mode singlets and multiplets which are <span class="hlt">modelled</span> using Higher Order Perturbation Theory (HOPT), taking into account the Earth’s rotation, ellipticity and lateral heterogeneities. A Monte Carlo exploration of the <span class="hlt">model</span> space is carried out, enabling the assessment of source parameter tradeoffs and uncertainties. We carry out synthetic tests to investigate errors in the source inversions due to: (i) unmodelled 3-D Earth structure; (ii) noise in the data; (iii) uncertainties in spatio-temporal <span class="hlt">earthquake</span> location; and, (iv) neglecting the source finiteness in point source inversions. We find that unmodelled 3-D structure is the most serious source of errors for rupture duration and length determinations especially for the lowest magnitude events. The errors in moment magnitude and fault mechanism are generally small, with the rake angle showing systematically larger errors (up to 20°). We then investigate five real thrust <span class="hlt">earthquakes</span> (Mw⩾8.5): (i) Sumatra-Andaman (26th December 2004); (ii) Nias, Sumatra (28th March 2005); (iii) Bengkulu (12th September 2007); (iv) Tohoku, Japan (11th March 2011); (v) Maule, Chile (27th February 2010); and, (vi) the 24 May 2013 Mw 8.3 Okhotsk Sea, Russia, deep (607 km) event. While finite source inversions for rupture length, duration, magnitude and fault mechanism are possible for the Sumatra-Andaman and Tohoku events, for all the other events their lower magnitudes only allow stable point source inversions of mode multiplets. We obtain the first normal mode finite source <span class="hlt">model</span> for the 2011 Tohoku <span class="hlt">earthquake</span>, which yields a fault length of 461 km, a rupture duration of 151 s, and hence an average rupture velocity of 3.05 km/s, giving an independent confirmation of the compact nature of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28503008','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28503008"><span>A new <span class="hlt">model</span> order reduction strategy adapted to nonlinear problems in <span class="hlt">earthquake</span> engineering.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Bamer, Franz; Amiri, Abbas Kazemi; Bucher, Christian</p> <p>2017-04-10</p> <p><span class="hlt">Earthquake</span> dynamic response analysis of large complex structures, especially in the presence of nonlinearities, usually turns out to be computationally expensive. In this paper, the methodical developments of a new <span class="hlt">model</span> order reduction strategy (MOR) based on the proper orthogonal decomposition (POD) method as well as its practical applicability to a realistic building structure are presented. The seismic performance of the building structure, a medical complex, is to be improved by means of base isolation realized by frictional pendulum bearings. According to the new introduced MOR strategy, a set of deterministic POD modes (transformation matrix) is assembled, which is derived based on the information of parts of the response history, so-called snapshots, of the structure under a representative <span class="hlt">earthquake</span> excitation. Subsequently, this transformation matrix is utilized to create reduced-order <span class="hlt">models</span> of the structure subjected to different <span class="hlt">earthquake</span> excitations. These sets of nonlinear low-order representations are now solved in a fractional amount of time in comparison with the computations of the full (non-reduced) systems. The results demonstrate accurate approximations of the physical (full) responses by means of this new MOR strategy if the probable behavior of the structure has already been captured in the POD snapshots. Copyright © 2016 The Authors. <span class="hlt">Earthquake</span> Engineering & Structural Dynamics Published by John Wiley & Sons Ltd.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S21B2031H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S21B2031H"><span>Improving three dimensional velocity <span class="hlt">model</span> for Puerto Rico - Virgin Islands for rapid <span class="hlt">earthquake</span> re-locations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huerfano, V. A.; Lopez, A. M.; Castillo, L.; Baez-Sanchez, G.; Soto-Cordero, L.; Lin, G.; Zhang, Q.</p> <p>2010-12-01</p> <p>Puerto Rico and the Virgin Islands (PRVI) block lie on the northeastern boundary of the Caribbean plate, where active transpressional tectonics result in the deformation of the boundaries of this block. Every year hundreds of <span class="hlt">earthquakes</span> occur within and around PRVI region and at least four destructive <span class="hlt">earthquakes</span> after 1700 are documented in the historical records. The mission of the Puerto Rico Seismic Network (PRSN), Department of Geology of the University of Puerto Rico in Mayagüez is to detect, analyze, disseminate <span class="hlt">earthquake</span>/tsunami messages and investigate the seismicity in the PR/VI. Currently the PRSN operates 30 seismic stations and receive real time stream from over 75 station installed around the Caribbean. 25 years worth of data recorded by the PRSN has been quality checked and compiled to constrain a new velocity structure using the tomographic package TomoDD. Currently at PRSN, the velocity structure to perform real-time determination of hypocenters consists of a 1-D <span class="hlt">model</span>. Therefore, this ambitious tomographic study seek to produce a more comprehensive velocity <span class="hlt">model</span> to be implemented at the PRSN for the daily <span class="hlt">earthquake</span> locations. Results from this study are a collaborative effort between the University of Miami and the University of Puerto Rico - Mayaguez.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70022356','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70022356"><span>Viscoelastic-coupling <span class="hlt">model</span> for the <span class="hlt">earthquake</span> cycle driven from below</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Savage, J.C.</p> <p>2000-01-01</p> <p>In a linear system the <span class="hlt">earthquake</span> cycle can be represented as the sum of a solution which reproduces the <span class="hlt">earthquake</span> cycle itself (viscoelastic-coupling <span class="hlt">model</span>) and a solution that provides the driving force. We consider two cases, one in which the <span class="hlt">earthquake</span> cycle is driven by stresses transmitted along the schizosphere and a second in which the cycle is driven from below by stresses transmitted along the upper mantle (i.e., the schizosphere and upper mantle, respectively, act as stress guides in the lithosphere). In both cases the driving stress is attributed to steady motion of the stress guide, and the upper crust is assumed to be elastic. The surface deformation that accumulates during the interseismic interval depends solely upon the <span class="hlt">earthquake</span>-cycle solution (viscoelastic-coupling <span class="hlt">model</span>) not upon the driving source solution. Thus geodetic observations of interseismic deformation are insensitive to the source of the driving forces in a linear system. In particular, the suggestion of Bourne et al. [1998] that the deformation that accumulates across a transform fault system in the interseismic interval is a replica of the deformation that accumulates in the upper mantle during the same interval does not appear to be correct for linear systems.</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('http://adsabs.harvard.edu/abs/2012GeoJI.189..602B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012GeoJI.189..602B"><span>Constructing a Hidden Markov <span class="hlt">Model</span> based <span class="hlt">earthquake</span> detector: application to induced seismicity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beyreuther, Moritz; Hammer, Conny; Wassermann, Joachim; Ohrnberger, Matthias; Megies, Tobias</p> <p>2012-04-01</p> <p>The triggering or detection of seismic events out of a continuous seismic data stream is one of the key issues of an automatic or semi-automatic seismic monitoring system. In the case of dense networks, either local or global, most of the implemented trigger algorithms are based on a large number of active stations. However, in the case of only few available stations or small events, for example, like in monitoring volcanoes or hydrothermal power plants, common triggers often show high false alarms. In such cases detection algorithms are of interest, which show reasonable performance when operating even on a single station. In this context, we apply Hidden Markov <span class="hlt">Models</span> (HMM) which are algorithms borrowed from speech recognition. However, many pitfalls need to be avoided to apply speech recognition technology directly to <span class="hlt">earthquake</span> detection. We show the fit of the <span class="hlt">model</span> parameters in an innovative way. State clustering is introduced to refine the intrinsically assumed time dependency of the HMMs and we explain the effect coda has on the recognition results. The methodology is then used for the detection of anthropogenicly induced <span class="hlt">earthquakes</span> for which we demonstrate for a period of 3.9 months of continuous data that the single station HMM <span class="hlt">earthquake</span> detector can achieve similar detection rates as a common trigger in combination with coincidence sums over two stations. To show the general applicability of state clustering we apply the proposed method also to <span class="hlt">earthquake</span> classification at Mt. Merapi volcano, Indonesia.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004GeoJI.157.1233O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004GeoJI.157.1233O"><span>Search for direct empirical spatial correlation signatures of the critical triggering <span class="hlt">earthquake</span> <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ouillon, G.; Sornette, D.</p> <p>2004-06-01</p> <p>We propose a new test of the critical <span class="hlt">earthquake</span> <span class="hlt">model</span> based on the hypothesis that precursory <span class="hlt">earthquakes</span> are `actors' that create fluctuations in the stress field which exhibit an increasing correlation length as the critical large event becomes imminent. Our approach constitutes an attempt to build a more physically based time-dependent indicator (cumulative scalar stress function), in the spirit of, but improving on, the cumulative Benioff strain used in previous works documenting the phenomenon of accelerating seismicity. Using a simplified scalar space and time-dependent viscoelastic Green's function in a two-layer <span class="hlt">model</span> of the Earth's lithosphere, we compute spatiotemporal pseudo-stress fluctuations induced by a series of events before four of the largest recent shocks in southern California. Through an appropriate spatial wavelet transform, we then estimate the contribution of each event in the series to the correlation properties of the simplified pseudo-stress field around the location of the mainshock at different scales. This allows us to define a cumulative scalar pseudo-stress function which reveals neither an acceleration of stress storage at the epicentre of the mainshock nor an increase of the spatial stress-stress correlation length similar to those observed previously for the cumulative Benioff strain. The <span class="hlt">earthquakes</span> we studied are thus either simple `witnesses' of a large-scale tectonic organization, or are simply unrelated, and/or the Green's function describing interactions between <span class="hlt">earthquakes</span> has a significantly longer range than predicted for standard viscoelastic media used here.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70118276','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70118276"><span>Conditional spectrum computation incorporating multiple causal <span class="hlt">earthquakes</span> and ground-motion prediction <span class="hlt">models</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>Lin, Ting; Harmsen, Stephen C.; Baker, Jack W.; Luco, Nicolas</p> <p>2013-01-01</p> <p>The conditional spectrum (CS) is a target spectrum (with conditional mean and conditional standard deviation) that links seismic hazard information with ground-motion selection for nonlinear dynamic analysis. Probabilistic seismic hazard analysis (PSHA) estimates the ground-motion hazard by incorporating the aleatory uncertainties in all <span class="hlt">earthquake</span> scenarios and resulting ground motions, as well as the epistemic uncertainties in ground-motion prediction <span class="hlt">models</span> (GMPMs) and seismic source <span class="hlt">models</span>. Typical CS calculations to date are produced for a single <span class="hlt">earthquake</span> scenario using a single GMPM, but more precise use requires consideration of at least multiple causal <span class="hlt">earthquakes</span> and multiple GMPMs that are often considered in a PSHA computation. This paper presents the mathematics underlying these more precise CS calculations. Despite requiring more effort to compute than approximate calculations using a single causal <span class="hlt">earthquake</span> and GMPM, the proposed approach produces an exact output that has a theoretical basis. To demonstrate the results of this approach and compare the exact and approximate calculations, several example calculations are performed for real sites in the western United States. The results also provide some insights regarding the circumstances under which approximate results are likely to closely match more exact results. To facilitate these more precise calculations for real applications, the exact CS calculations can now be performed for real sites in the United States using new deaggregation features in the U.S. Geological Survey hazard mapping tools. Details regarding this implementation are discussed in this paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFMNH43C..05I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFMNH43C..05I"><span>Seismic hazard assessment in the Tibet-Himalayan region based on observed and <span class="hlt">modeled</span> extreme <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>Ismail-Zadeh, A.; Sokolov, V. Y.</p> <p>2013-12-01</p> <p>Ground shaking due to recent catastrophic <span class="hlt">earthquakes</span> are estimated to be significantly higher than that predicted by a probabilistic seismic hazard analysis (PSHA). A reason is that extreme (large magnitude and rare) seismic events are not accounted in PSHA in the most cases due to the lack of information and unknown reoccurrence time of the extremes. We present a new approach to assessment of regional seismic hazard, which incorporates observed (recorded and historic) seismicity and <span class="hlt">modeled</span> extreme events. We apply this approach to PSHA of the Tibet-Himalayan region. The large magnitude events simulated for several thousand years in <span class="hlt">models</span> of lithospheric block-and-fault dynamics and consistent with the regional geophysical and geodetic data are employed together with the observed <span class="hlt">earthquakes</span> for the Monte-Carlo PSHA. <span class="hlt">Earthquake</span> scenarios are generated stochastically to sample the magnitude and spatial distribution of seismicity (observed and <span class="hlt">modeled</span>) as well as the distribution of ground motion for each seismic event. The peak ground acceleration (PGA) values (that is, ground shaking at a site), which are expected to be exceeded at least once in 50 years with a probability of 10%, are mapped and compared to those PGA values observed and predicted earlier. The results show that the PGA values predicted by our assessment fit much better the observed ground shaking due to the 2008 Wenchuan <span class="hlt">earthquake</span> than those predicted by conventional PSHA. Our approach to seismic hazard assessment provides a better understanding of ground shaking due to possible large-magnitude events and could be useful for risk assessment, <span class="hlt">earthquake</span> engineering purposes, and emergency planning.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.T33B2258S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.T33B2258S"><span>3-D cell <span class="hlt">model</span> simulation of the inland <span class="hlt">earthquake</span> generation pattern in Southwest Japan during the Nankai <span class="hlt">earthquake</span> cycles in a layered viscoelastic medium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shikakura, Y.; Fukahata, Y.; Mitsui, N.; Hirahara, K.</p> <p>2010-12-01</p> <p>In southwest Japan, there are a lot of inland active faults, such as Median Tectonic Line, the Neodani, Atotsugawa, and Rokko-Awaji faults. The <span class="hlt">earthquakes</span> in these faults are mainly generated by the east-west compressive stress due to the Pacific plate subduction. However, because the activity of inland <span class="hlt">earthquakes</span> increases in the period from 50 years before to 10 years after the great interplate <span class="hlt">earthquakes</span> (Hori & Oike, 1999), <span class="hlt">earthquake</span> generations in these faults are affected by the interplate <span class="hlt">earthquakes</span> and collision of the Izu volcanic arc due to the Philippine Sea (PHS) plate subduction. To evaluate the effects quantitatively, we <span class="hlt">model</span> the stress accumulation/release processes at the inland active faults in southwest Japan. For this problem, Pollitz & Sacks (1997), Hyodo & Hirahara (2004), and Hirahara (2007) evaluated the viscoelastic effect of great interplate <span class="hlt">earthquakes</span> at the PHS plate subduction by examining Coulomb Failure Function ΔCFF. We here simulate <span class="hlt">earthquake</span> generation pattern at inland active faults in southwest Japan by solving the boundary value problem. The governing equations are the slip response function and the friction constitutive law. The boundary conditions are east-west compressive stress due to the Pacific plate subduction, the interplate <span class="hlt">earthquakes</span> and collision of the Izu volcanic arc due to the PHS plate subduction, and the geometry of plate interfaces and inland active faults. We here compute the slip response function in an elastic-viscoelastic stratified medium. We employ quasi-static viscoelastic slip response functions for point sources by Fukahata & Matsu’ura (2006). To obtain accurate slip response functions for rectangular sources effectively, we apply the Gauss-Legendre integration scheme. We use the approximate solutions under the assumption that slip response exponentially decays with time, since it is difficult to calculate viscoelastic slip response functions for all time steps. To approximate quasi</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26959647','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26959647"><span>An Integrated and Interdisciplinary <span class="hlt">Model</span> for Predicting the Risk of Injury and Death in Future <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>Shapira, Stav; Novack, Lena; Bar-Dayan, Yaron; Aharonson-Daniel, Limor</p> <p>2016-01-01</p> <p>A comprehensive technique for <span class="hlt">earthquake</span>-related casualty estimation remains an unmet challenge. This study aims to integrate risk factors related to characteristics of the exposed population and to the built environment in order to improve communities' preparedness and response capabilities and to mitigate future consequences. An innovative <span class="hlt">model</span> was formulated based on a widely used loss estimation <span class="hlt">model</span> (HAZUS) by integrating four human-related risk factors (age, gender, physical disability and socioeconomic status) that were identified through a systematic review and meta-analysis of epidemiological data. The common effect measures of these factors were calculated and entered to the existing <span class="hlt">model</span>'s algorithm using logistic regression equations. Sensitivity analysis was performed by conducting a casualty estimation simulation in a high-vulnerability risk area in Israel. the integrated <span class="hlt">model</span> outcomes indicated an increase in the total number of casualties compared with the prediction of the traditional <span class="hlt">model</span>; with regard to specific injury levels an increase was demonstrated in the number of expected fatalities and in the severely and moderately injured, and a decrease was noted in the lightly injured. Urban areas with higher populations at risk rates were found more vulnerable in this regard. The proposed <span class="hlt">model</span> offers a novel approach that allows quantification of the combined impact of human-related and structural factors on the results of <span class="hlt">earthquake</span> casualty <span class="hlt">modelling</span>. Investing efforts in reducing human vulnerability and increasing resilience prior to an occurrence of an <span class="hlt">earthquake</span> could lead to a possible decrease in the expected number of casualties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/945662','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/945662"><span>REGIONAL SEISMIC AMPLITUDE <span class="hlt">MODELING</span> AND TOMOGRAPHY FOR <span class="hlt">EARTHQUAKE</span>-EXPLOSION DISCRIMINATION</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Walter, W R; Pasyanos, M E; Matzel, E; Gok, R; Sweeney, J; Ford, S R; Rodgers, A J</p> <p>2008-07-08</p> <p>We continue exploring methodologies to improve <span class="hlt">earthquake</span>-explosion discrimination using regional amplitude ratios such as P/S in a variety of frequency bands. Empirically we demonstrate that such ratios separate explosions from <span class="hlt">earthquakes</span> using closely located pairs of <span class="hlt">earthquakes</span> and explosions recorded on common, publicly available stations at test sites around the world (e.g. Nevada, Novaya Zemlya, Semipalatinsk, Lop Nor, India, Pakistan, and North Korea). We are also examining if there is any relationship between the observed P/S and the point source variability revealed by longer period full waveform <span class="hlt">modeling</span> (e. g. Ford et al 2008). For example, regional waveform <span class="hlt">modeling</span> shows strong tectonic release from the May 1998 India test, in contrast with very little tectonic release in the October 2006 North Korea test, but the P/S discrimination behavior appears similar in both events using the limited regional data available. While regional amplitude ratios such as P/S can separate events in close proximity, it is also empirically well known that path effects can greatly distort observed amplitudes and make <span class="hlt">earthquakes</span> appear very explosion-like. Previously we have shown that the MDAC (Magnitude Distance Amplitude Correction, Walter and Taylor, 2001) technique can account for simple 1-D attenuation and geometrical spreading corrections, as well as magnitude and site effects. However in some regions 1-D path corrections are a poor approximation and we need to develop 2-D path corrections. Here we demonstrate a new 2-D attenuation tomography technique using the MDAC <span class="hlt">earthquake</span> source <span class="hlt">model</span> applied to a set of events and stations in both the Middle East and the Yellow Sea Korean Peninsula regions. We believe this new 2-D MDAC tomography has the potential to greatly improve <span class="hlt">earthquake</span>-explosion discrimination, particularly in tectonically complex regions such as the Middle East. Monitoring the world for potential nuclear explosions requires characterizing seismic</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S53D..01L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S53D..01L"><span>Oceanic transform fault <span class="hlt">earthquake</span> nucleation process and source scaling relations - A numerical <span class="hlt">modeling</span> study with rate-state friction (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Liu, Y.; McGuire, J. J.; Behn, M. D.</p> <p>2013-12-01</p> <p>We use a three-dimensional strike-slip fault <span class="hlt">model</span> in the framework of rate and state-dependent friction to investigate <span class="hlt">earthquake</span> behavior and scaling relations on oceanic transform faults (OTFs). Gabbro friction data under hydrothermal conditions are mapped onto OTFs using temperatures from (1) a half-space cooling <span class="hlt">model</span>, and (2) a thermal <span class="hlt">model</span> that incorporates a visco-plastic rheology, non-Newtonian viscous flow and the effects of shear heating and hydrothermal circulation. Without introducing small-scale frictional heterogeneities on the fault, our <span class="hlt">model</span> predicts that an OTF segment can transition between seismic and aseismic slip over many <span class="hlt">earthquake</span> cycles, consistent with the multimode hypothesis for OTF ruptures. The average seismic coupling coefficient χ is strongly dependent on the ratio of seismogenic zone width W to <span class="hlt">earthquake</span> nucleation size h*; χ increases by four orders of magnitude as W/h* increases from ~ 1 to 2. Specifically, the average χ = 0.15 +/- 0.05 derived from global OTF <span class="hlt">earthquake</span> catalogs can be reached at W/h* ≈ 1.2-1.7. The <span class="hlt">modeled</span> largest <span class="hlt">earthquake</span> rupture area is less than the total seismogenic area and we predict a deficiency of large <span class="hlt">earthquakes</span> on long transforms, which is also consistent with observations. <span class="hlt">Earthquake</span> magnitude and distribution on the Gofar (East Pacific Rise) and Romanche (equatorial Mid-Atlantic) transforms are better predicted using the visco-plastic <span class="hlt">model</span> than the half-space cooling <span class="hlt">model</span>. We will also investigate how fault gouge porosity variation during an OTF <span class="hlt">earthquake</span> nucleation phase may affect the seismic wave velocity structure, for which up to 3% drop was observed prior to the 2008 Mw6 Gofar <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920035260&hterms=plate+tectonics+earthquakes&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dplate%2Btectonics%2Bearthquakes','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920035260&hterms=plate+tectonics+earthquakes&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dplate%2Btectonics%2Bearthquakes"><span><span class="hlt">Models</span> of recurrent strike-slip <span class="hlt">earthquake</span> cycles and the state of crustal stress</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Lyzenga, Gregory A.; Raefsky, Arthur; Mulligan, Stephanie G.</p> <p>1991-01-01</p> <p>Numerical <span class="hlt">models</span> of the strike-slip <span class="hlt">earthquake</span> cycle, assuming a viscoelastic asthenosphere coupling <span class="hlt">model</span>, are examined. The time-dependent simulations incorporate a stress-driven fault, which leads to tectonic stress fields and <span class="hlt">earthquake</span> recurrence histories that are mutually consistent. Single-fault simulations with constant far-field plate motion lead to a nearly periodic <span class="hlt">earthquake</span> 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 <span class="hlt">models</span> 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. <span class="hlt">Models</span> incorporating both low-stress and high-stress fault strength assumptions are examined, under Newtonian and non-Newtonian rheology assumptions. <span class="hlt">Model</span> results suggest a preference for low-stress (a shear stress level of about 10 MPa) fault <span class="hlt">models</span>, in agreement with previous estimates based on heat flow measurements and other stress indicators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AGUFM.S43B1072M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AGUFM.S43B1072M"><span>Real time forecasts through physical and stochastic <span class="hlt">models</span> of <span class="hlt">earthquake</span> clustering</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Murru, M.; Console, R.; Catalli, F.; Falcone, G.</p> <p>2005-12-01</p> <p>The phenomenon of <span class="hlt">earthquake</span> interaction has become a popular subject of study because it can shed light on the physical processes leading to <span class="hlt">earthquakes</span>, and because it has a potential value for short-term <span class="hlt">earthquake</span> forecast and hazard mitigation. In this study we start from a purely stochastic approach known as the so-called epidemic <span class="hlt">model</span> (ETAS) introduced by Ogata in 1988 and its variations. Then we build up an approach by which this <span class="hlt">model</span> and the rate-and-state constitutive law introduced by Dieterich in the `90s have been merged in a single algorithm and statistically tested. Tests on real seismicity and comparison with a plain time-independent Poissonian <span class="hlt">model</span> through likelihood-based methods have reliably proved their validity. The <span class="hlt">models</span> are suitable for real-time forecast of the seismic activity. In the context of the low-magnitude Italian seismicity recorded from 1987 to 2005, the new <span class="hlt">model</span> incorporating the physical concept of the rate-and-state theory performs not better than the purely stochastic <span class="hlt">model</span>. Nevertheless, it has the advantage of needing a smaller number of free parameters and providing new interesting insights on the physics of the seismogenic process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70032943','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70032943"><span>Evaluation of CAMEL - comprehensive areal <span class="hlt">model</span> of <span class="hlt">earthquake</span>-induced landslides</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Miles, S.B.; Keefer, D.K.</p> <p>2009-01-01</p> <p>A new comprehensive areal <span class="hlt">model</span> of <span class="hlt">earthquake</span>-induced landslides (CAMEL) has been developed to assist in planning decisions related to disaster risk reduction. CAMEL provides an integrated framework for <span class="hlt">modeling</span> all types of <span class="hlt">earthquake</span>-induced landslides using fuzzy logic systems and geographic information systems. CAMEL is designed to facilitate quantitative and qualitative representation of terrain conditions and knowledge about these conditions on the likely areal concentration of each landslide type. CAMEL has been empirically evaluated with respect to disrupted landslides (Category I) using a case study of the 1989 M = 6.9 Loma Prieta, CA <span class="hlt">earthquake</span>. In this case, CAMEL performs best in comparison to disrupted slides and falls in soil. For disrupted rock fall and slides, CAMEL's performance was slightly poorer. The <span class="hlt">model</span> predicted a low occurrence of rock avalanches, when none in fact occurred. A similar comparison with the Loma Prieta case study was also conducted using a simplified Newmark displacement <span class="hlt">model</span>. The area under the curve method of evaluation was used in order to draw comparisons between both <span class="hlt">models</span>, revealing improved performance with CAMEL. CAMEL should not however be viewed as a strict alternative to Newmark displacement <span class="hlt">models</span>. CAMEL can be used to integrate Newmark displacements with other, previously incompatible, types of knowledge. ?? 2008 Elsevier B.V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMNH43A1826A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMNH43A1826A"><span>Field Investigations and a Tsunami <span class="hlt">Modeling</span> for the 1766 Marmara Sea <span class="hlt">Earthquake</span>, Turkey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aykurt Vardar, H.; Altinok, Y.; Alpar, B.; Unlu, S.; Yalciner, A. C.</p> <p>2016-12-01</p> <p>Turkey is located on one of the world's most hazardous <span class="hlt">earthquake</span> zones. The northern branch of the North Anatolian fault beneath the Sea of Marmara, where the population is most concentrated, is the most active fault branch at least since late Pliocene. The Sea of Marmara region has been affected by many large tsunamigenic <span class="hlt">earthquakes</span>; the most destructive ones are 549, 553, 557, 740, 989, 1332, 1343, 1509, 1766, 1894, 1912 and 1999 events. In order to understand and determine the tsunami potential and their possible effects along the coasts of this inland sea, detailed documentary, geophysical and numerical <span class="hlt">modelling</span> studies are needed on the past <span class="hlt">earthquakes</span> and their associated tsunamis whose effects are presently unknown.On the northern coast of the Sea of Marmara region, the Kucukcekmece Lagoon has a high potential to trap and preserve tsunami deposits. Within the scope of this study, lithological content, composition and sources of organic matters in the lagoon's bottom sediments were studied along a 4.63 m-long piston core recovered from the SE margin of the lagoon. The sedimentary composition and possible sources of the organic matters along the core were analysed and their results were correlated with the historical events on the basis of dating results. Finally, a tsunami scenario was tested for May 22nd 1766 Marmara Sea <span class="hlt">Earthquake</span> by using a widely used tsunami simulation <span class="hlt">model</span> called NAMIDANCE. The results show that the candidate tsunami deposits at the depths of 180-200 cm below the lagoons bottom were related with the 1766 (May) <span class="hlt">earthquake</span>. This work was supported by the Scientific Research Projects Coordination Unit of Istanbul University (Project 6384) and by the EU project TRANSFER for coring.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.S33G..07V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.S33G..07V"><span>Large Subduction <span class="hlt">Earthquake</span> Simulations using Finite Source <span class="hlt">Modeling</span> and the Offshore-Onshore Ambient Seismic Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Viens, L.; Miyake, H.; Koketsu, K.</p> <p>2016-12-01</p> <p>Large subduction <span class="hlt">earthquakes</span> have the potential to generate strong long-period ground motions. The ambient seismic field, also called seismic noise, contains information about the elastic response of the Earth between two seismic stations that can be retrieved using seismic interferometry. The DONET1 network, which is composed of 20 offshore stations, has been deployed atop the Nankai subduction zone, Japan, to continuously monitor the seismotectonic activity in this highly seismically active region. The surrounding onshore area is covered by hundreds of seismic stations, which are operated the National Research Institute for Earth Science and Disaster Prevention (NIED) and the Japan Meteorological Agency (JMA), with a spacing of 15-20 km. We retrieve offshore-onshore Green's functions from the ambient seismic field using the deconvolution technique and use them to simulate the long-period ground motions of moderate subduction <span class="hlt">earthquakes</span> that occurred at shallow depth. We extend the point source method, which is appropriate for moderate events, to finite source <span class="hlt">modeling</span> to simulate the long-period ground motions of large Mw 7 class <span class="hlt">earthquake</span> scenarios. The source <span class="hlt">models</span> are constructed using scaling relations between moderate and large <span class="hlt">earthquakes</span> to discretize the fault plane of the large hypothetical events into subfaults. Offshore-onshore Green's functions are spatially interpolated over the fault plane to obtain one Green's function for each subfault. The interpolated Green's functions are finally summed up considering different rupture velocities. Results show that this technique can provide additional information about <span class="hlt">earthquake</span> ground motions that can be used with the existing physics-based simulations to improve seismic hazard assessment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017GeoJI.208..715P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017GeoJI.208..715P"><span>Insights into pulverized rock formation from dynamic rupture <span class="hlt">models</span> 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>Payne, R. M.; Duan, B.</p> <p>2017-02-01</p> <p>Pulverized rocks (PR) are extremely incohesive and highly fractured rocks found within the damage zones of several large strike-slip faults around the world. They maintain their crystal structure, show little evidence of shearing or chemical alteration, and are believed to be produced by strong tensile forces. Several mechanisms for pulverization have been proposed based on simple qualitative analyses or laboratory experiments under simplified loading conditions. Numerical <span class="hlt">modelling</span>, however, can offer new insights into what is needed to produce PR and likely conditions of formation. We perform dynamic rupture simulations of different <span class="hlt">earthquakes</span>, varying the magnitude, the slip distribution, and the rupture speed (supershear and subshear), while measuring the stresses produced away from the fault. To contextualize our results, a basic threshold of 10 MPa is set as the tensile strength of the rock mass and recordings are made of where, when, and by how much this threshold is exceeded for each <span class="hlt">earthquake</span> type. Guided by field observations, we discern that a large (>Mw 7.1) subshear <span class="hlt">earthquake</span> along a bimaterial fault produces a pulverized rock distribution most consistent with observations. The damage is asymmetric with the majority on the stiffer side of the fault extending out for several hundred metres. Within this zone there is a large and sudden volumetric expansion in all directions as the rupture passes. We propose that such an extreme tensile stress state, repeated for every <span class="hlt">earthquake</span>, eventually produces the PR seen in the field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70014783','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70014783"><span><span class="hlt">Modelling</span> aftershock migration and afterslip of the San Juan Bautista, California, <span class="hlt">earthquake</span> of October 3, 1972</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Wesson, R.L.</p> <p>1987-01-01</p> <p>The San Juan Bautista <span class="hlt">earthquake</span> of October 3, 1972 (ML = 4.8), located along the San Andreas fault in central California, initiated an aftershock sequence characterized by a subtle, but perceptible, tendency for aftershocks to spread to the northwest and southeast along the fault zone. The apparent dimension of the aftershock zone along strike increased from about 7-10 km within a few days of the <span class="hlt">earthquake</span>, to about 20 km eight months later. In addition, the mainshock initiated a period of accelerated fault creep, which was observed at 2 creep meters situated astride the trace of the San Andreas fault within about 15 km of the epicenter of the mainshock. The creep rate gradually returned to the preearthquake rate after about 3 yrs. Both the spreading of the aftershocks and the rapid surface creep are interpreted as reflecting a period of rapid creep in the fault zone representing the readjustment of stress and displacement following the failure of a "stuck" patch or asperity during the San Juan Bautista <span class="hlt">earthquake</span>. Numerical calculations suggest that the behavior of the fault zone is consistent with that of a material characterized by a viscosity of about 3.6??1014 P, although the real rheology is likely to be more complicated. In this <span class="hlt">model</span>, the mainshock represents the failure of an asperity that slips only during <span class="hlt">earthquakes</span>. Aftershocks represent the failure of second-order asperities which are dragged along by the creeping fault zone. ?? 1987.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.tmp..466P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.tmp..466P"><span>Insights into Pulverized Rock Formation from Dynamic Rupture <span class="hlt">Models</span> 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>Payne, R. M.; Duan, B.</p> <p>2016-11-01</p> <p>Pulverized rocks (PR) are extremely incohesive and highly fractured rocks found within the damage zones of several large strike-slip faults around the world. They maintain their crystal structure, show little evidence of shearing or chemical alteration, and are believed to be produced by strong tensile forces. Several mechanisms for pulverization have been proposed based on simple qualitative analyses or laboratory experiments under simplified loading conditions. Numerical <span class="hlt">modeling</span>, however, can offer new insights into what is needed to produce PR and likely conditions of formation. We perform dynamic rupture simulations of different <span class="hlt">earthquakes</span>, varying the magnitude, the slip distribution, and the rupture speed (supershear and subshear), while measuring the stresses produced away from the fault. To contextualize our results, a basic threshold of 10 MPa is set as the tensile strength of the rock mass and recordings are made of where, when, and by how much this threshold is exceeded for each <span class="hlt">earthquake</span> type. Guided by field observations, we discern that a large (> Mw 7.1) subshear <span class="hlt">earthquake</span> along a bimaterial fault produces a pulverized rock distribution most consistent with observations. The damage is asymmetric with the majority on the stiffer side of the fault extending out for several hundred meters. Within this zone there is a large and sudden volumetric expansion in all directions as the rupture passes. We propose that such an extreme tensile stress state, repeated for every <span class="hlt">earthquake</span>, eventually produces the PR seen in the field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015A%26A...577A..55D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015A%26A...577A..55D"><span><span class="hlt">Non-conservative</span> evolution in Algols: where is the matter?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deschamps, R.; Braun, K.; Jorissen, A.; Siess, L.; Baes, M.; Camps, P.</p> <p>2015-05-01</p> <p>Context. There is indirect evidence of <span class="hlt">non-conservative</span> evolutions in Algols. However, the systemic mass-loss rate is poorly constrained by observations and generally set as a free parameter in binary-star evolution simulations. Moreover, systemic mass loss may lead to observational signatures that still need to be found. Aims: Within the "hotspot" ejection mechanism, some of the material that is initially transferred from the companion star via an accretion stream is expelled from the system due to the radiative energy released on the gainer's surface by the impacting material. The objective of this paper is to retrieve observable quantities from this process and to compare them with observations. Methods: We investigate the impact of the outflowing gas and the possible presence of dust grains on the spectral energy distribution (SED). We used the 1D plasma code Cloudy and compared the results with the 3D Monte-Carlo radiative transfer code Skirt for dusty simulations. The circumbinary mass-distribution and binary parameters were computed with state-of-the-art binary calculations done with the Binstar evolution code. Results: The outflowing material reduces the continuum flux level of the stellar SED in the optical and UV. Because of the time-dependence of this effect, it may help to distinguish between different ejection mechanisms. If present, dust leads to observable infrared excesses, even with low dust-to-gas ratios, and traces the cold material at large distances from the star. By searching for this dust emission in the WISE catalogue, we found a small number of Algols showing infrared excesses, among which the two rather surprising objects SX Aur and CZ Vel. We find that some binary B[e] stars show the same strong Balmer continuum as we predict with our <span class="hlt">models</span>. However, direct evidence of systemic mass loss is probably not observable in genuine Algols, since these systems no longer eject mass through the hotspot mechanism. Furthermore, owing to its high</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814895C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814895C"><span>The use of the Finite Element method for the <span class="hlt">earthquakes</span> <span class="hlt">modelling</span> in different geodynamic environments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Castaldo, Raffaele; Tizzani, Pietro</p> <p>2016-04-01</p> <p>Many numerical <span class="hlt">models</span> have been developed to simulate the deformation and stress changes associated to the faulting process. This aspect is an important topic in fracture mechanism. In the proposed study, we investigate the impact of the deep fault geometry and tectonic setting on the co-seismic ground deformation pattern associated to different <span class="hlt">earthquake</span> phenomena. We exploit the impact of the structural-geological data in Finite Element environment through an optimization procedure. In this framework, we <span class="hlt">model</span> the failure processes in a physical mechanical scenario to evaluate the kinematics associated to the Mw 6.1 L'Aquila 2009 <span class="hlt">earthquake</span> (Italy), the Mw 5.9 Ferrara and Mw 5.8 Mirandola 2012 <span class="hlt">earthquake</span> (Italy) and the Mw 8.3 Gorkha 2015 <span class="hlt">earthquake</span> (Nepal). These seismic events are representative of different tectonic scenario: the normal, the reverse and thrust faulting processes, respectively. In order to simulate the kinematic of the analyzed natural phenomena, we assume, under the plane stress approximation (is defined to be a state of stress in which the normal stress, sz, and the shear stress sxz and syz, directed perpendicular to x-y plane are assumed to be zero), the linear elastic behavior of the involved media. The performed finite element procedure consist of through two stages: (i) compacting under the weight of the rock successions (gravity loading), the deformation <span class="hlt">model</span> reaches a stable equilibrium; (ii) the co-seismic stage simulates, through a distributed slip along the active fault, the released stresses. To constrain the <span class="hlt">models</span> solution, we exploit the DInSAR deformation velocity maps retrieved by satellite data acquired by old and new generation sensors, as ENVISAT, RADARSAT-2 and SENTINEL 1A, encompassing the studied <span class="hlt">earthquakes</span>. More specifically, we first generate 2D several forward mechanical <span class="hlt">models</span>, then, we compare these with the recorded ground deformation fields, in order to select the best boundaries setting and parameters. Finally</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JAESc.147..240S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JAESc.147..240S"><span>Source <span class="hlt">model</span> estimation of the 2005 Kyushu <span class="hlt">Earthquake</span>, Japan using Modified Semi Empirical Technique</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sandeep; Joshi, A.; Sah, S. K.; Kumar, Parveen; Lal, Sohan; Vandana; Kamal; Singh, R. S.</p> <p>2017-10-01</p> <p>The 2005 Kyushu <span class="hlt">earthquake</span> (MW 6.6, MJMA 7.0) occurred northwest of Fukuoka, Japan causing much damage and injuries. Here, we <span class="hlt">model</span> the <span class="hlt">earthquake</span>'s source using the data recorded at surrounding field stations. Two isolated strong motion generation areas (SMGA) are identified on the rupture plane. The parameters of each SMGA are estimated using source displacement spectra and then used the spatiotemporal distribution of aftershocks to identify possible locations of SMGAs on the rupture plane. A modified semi empirical technique (MSET) simulated the records for the estimated rupture <span class="hlt">model</span>. We then compared the observed and simulated acceleration records from eight regional stations. A comparable match between the observed and simulated records confirms the robustness of two SMGA rupture <span class="hlt">model</span> and ability of MSET to simulate strong ground motion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4186249','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4186249"><span>Evolution of wealth in a <span class="hlt">non-conservative</span> economy driven by local Nash equilibria</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Degond, Pierre; Liu, Jian-Guo; Ringhofer, Christian</p> <p>2014-01-01</p> <p>We develop a <span class="hlt">model</span> for the evolution of wealth in a <span class="hlt">non-conservative</span> economic environment, extending a theory developed in Degond et al. (2014 J. Stat. Phys. 154, 751–780 (doi:10.1007/s10955-013-0888-4)). The <span class="hlt">model</span> considers a system of rational agents interacting in a game-theoretical framework. This evolution drives the dynamics of the agents in both wealth and economic configuration variables. The cost function is chosen to represent a risk-averse strategy of each agent. That is, the agent is more likely to interact with the market, the more predictable the market, and therefore the smaller its individual risk. This yields a kinetic equation for an effective single particle agent density with a Nash equilibrium serving as the local thermodynamic equilibrium. We consider a regime of scale separation where the large-scale dynamics is given by a hydrodynamic closure with this local equilibrium. A class of generalized collision invariants is developed to overcome the difficulty of the <span class="hlt">non-conservative</span> property in the hydrodynamic closure derivation of the large-scale dynamics for the evolution of wealth distribution. The result is a system of gas dynamics-type equations for the density and average wealth of the agents on large scales. We recover the inverse Gamma distribution, which has been previously considered in the literature, as a local equilibrium for particular choices of the cost function. PMID:25288808</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/25288808','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25288808"><span>Evolution of wealth in a <span class="hlt">non-conservative</span> economy driven by local Nash equilibria.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Degond, Pierre; Liu, Jian-Guo; Ringhofer, Christian</p> <p>2014-11-13</p> <p>We develop a <span class="hlt">model</span> for the evolution of wealth in a <span class="hlt">non-conservative</span> economic environment, extending a theory developed in Degond et al. (2014 J. Stat. Phys. 154, 751-780 (doi:10.1007/s10955-013-0888-4)). The <span class="hlt">model</span> considers a system of rational agents interacting in a game-theoretical framework. This evolution drives the dynamics of the agents in both wealth and economic configuration variables. The cost function is chosen to represent a risk-averse strategy of each agent. That is, the agent is more likely to interact with the market, the more predictable the market, and therefore the smaller its individual risk. This yields a kinetic equation for an effective single particle agent density with a Nash equilibrium serving as the local thermodynamic equilibrium. We consider a regime of scale separation where the large-scale dynamics is given by a hydrodynamic closure with this local equilibrium. A class of generalized collision invariants is developed to overcome the difficulty of the <span class="hlt">non-conservative</span> property in the hydrodynamic closure derivation of the large-scale dynamics for the evolution of wealth distribution. The result is a system of gas dynamics-type equations for the density and average wealth of the agents on large scales. We recover the inverse Gamma distribution, which has been previously considered in the literature, as a local equilibrium for particular choices of the cost function.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFMNH21C1527G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFMNH21C1527G"><span>PTHA Slip <span class="hlt">Models</span> in the Aftermath of the 2011 Tohoku <span class="hlt">Earthquake</span> and Tsunami</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geist, E. L.; Parsons, T.; Oglesby, D. D.</p> <p>2011-12-01</p> <p>Inter-plate thrust slip <span class="hlt">models</span> used in Probabilistic Tsunami Hazard Analysis (PTHA) are re-evaluated in light of the 2011 Tohoku <span class="hlt">earthquake</span> and tsunami. Whereas recurrence is typically linked to seismic moment in PTHA, the magnitude and distribution of slip are the primary variables that affect tsunami generation. Because of the self-similar nature of rupture, the slip <span class="hlt">model</span> is dependent on other scaling relationships, such as magnitude-area and magnitude-mean slip. In the past, various slip <span class="hlt">models</span> have been used to calculate tsunami generation, ranging from uniform slip to stochastic <span class="hlt">models</span>. Uniform slip <span class="hlt">models</span> systematically underestimate the amplitude and leading-wave steepness for the local, broadside tsunami. Stochastic slip <span class="hlt">models</span>, constrained by the seismic displacement spectrum, produce a range of possible slip distributions for a given seismic moment and slip spectrum and more accurately represent heterogeneous <span class="hlt">earthquake</span> ruptures. Conventional stochastic slip <span class="hlt">models</span> based on a k-2 slip spectrum and Gaussian random variables result in a coefficient of variation (c.v.) approximately equal to 0.5. However, slip inversion results of recent tsunamigenic <span class="hlt">earthquakes</span> indicate that the observed c.v. is significantly greater than 0.5. This is particularly evident for the 2011 Tohoku <span class="hlt">earthquake</span>, in which the c.v. for slip is approximately 1.0. Recent updates to the stochastic slip <span class="hlt">model</span> can retain a k-2 slip spectrum, but use non-Gaussian distributed random variables. The updated stochastic slip <span class="hlt">model</span> is more consistent with the observed fluctuations in slip. We investigate how these <span class="hlt">models</span> can be applied in a PTHA framework. In addition, dynamic effects such as amplification of slip near the free surface, partitioning of slip between different overlapping fault segments, and dynamic overshoot can strongly modify the slip pattern in ways that may be correlated with geometrical and frictional properties on the fault; such effects potentially may be predictable prior</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.7018S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.7018S"><span>The 2015, Mw 6.5, Leucas (Ionian Sea, Greece) <span class="hlt">earthquake</span>: Seismological and Geodetic <span class="hlt">Modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saltogianni, Vasso; Taymaz, Tuncay; Yolsal-Çevikbilen, Seda; Eken, Tuna; Moschas, Fanis; Stiros, Stathis</p> <p>2016-04-01</p> <p>A cluster of <span class="hlt">earthquakes</span> (6<Ms <7) characterized by strike slip faulting have occurred along the NW edge of the Aegean Arc in the Ionian Sea, the most seismically active region in Greece, in the last 30 years. The most recent <span class="hlt">earthquake</span> was the 2015 (Mw 6.5) Leucas (Lefkada) <span class="hlt">earthquake</span>. The <span class="hlt">modelling</span> of these <span class="hlt">earthquakes</span>, some of which are double events (2003 Leucas; 2014 Cephalonia) is a challenge for two main reasons. First, the geography of the area limits the distribution of the available seismological and GNSS stations and the correlations of INSAR data. Second, the structural pattern of the area indicates distributed thrusting but recent <span class="hlt">earthquakes</span> are confined to the west margin of the Aegean Arc, usually assigned to the Cephalonia Transform Fault (CTF), and are dominated by strike slip faulting. In order to contribute to the understanding active tectonics along this critical region, our study was based on the independent analysis of the seismological and geodetic signature of the 2015 <span class="hlt">earthquake</span> and the on the joint evaluation of the inferred <span class="hlt">models</span> on the basis of the fault pattern of the area and of previous <span class="hlt">earthquakes</span>. First, based on teleseismic long-period P- and SH- and broad-band P-waveforms a point-source solution at the SW part of Leucas yielded dominantly right-lateral strike-slip faulting mechanisms (strike: 23o, dip: 68o, rake: -170o) with a shallow focal depth (h: 9 km) and with seismic moment of Mo: 10.4x1018 Nm. Furthermore, the rupture history of the <span class="hlt">earthquake</span> was obtained by applying a new back-projection method that uses teleseismic P-waveforms to integrate the direct P-phase with reflected phases from structural discontinuities near the source. In the slip inversion the faulting occurs on a single fault plane (strike and dip are obtained from the best fitting point-source solution) and slip (rake) angle varied during the whole rupture process. Second, co-seismic displacements were derived from eight permanent and one campaign GPS</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011JGRB..116.2308F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011JGRB..116.2308F"><span>A revised tsunami source <span class="hlt">model</span> for the 1707 Hoei <span class="hlt">earthquake</span> and simulation of tsunami inundation of Ryujin Lake, Kyushu, Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Furumura, Takashi; Imai, Kentaro; Maeda, Takuto</p> <p>2011-02-01</p> <p>Based on many recent findings such as those for geodetic data from Japan's GEONET nationwide GPS network and geological investigations of a tsunami-inundated Ryujin Lake in Kyushu, we present a revised source rupture <span class="hlt">model</span> for the great 1707 Hoei <span class="hlt">earthquake</span> that occurred in the Nankai Trough off southwestern Japan. The source rupture area of the new Hoei <span class="hlt">earthquake</span> source <span class="hlt">model</span> extends further, to the Hyuga-nada, more than 70 km beyond the currently accepted location at the westernmost end of Shikoku. Numerical simulation of the tsunami using a new source rupture <span class="hlt">model</span> for the Hoei <span class="hlt">earthquake</span> explains the distribution of the very high tsunami observed along the Pacific coast from western Shikoku to Kyushu more consistently. A simulation of the tsunami runup into Ryujin Lake using the onshore tsunami estimated by the new <span class="hlt">model</span> demonstrates a tsunami inundation process; inflow and outflow speeds affect transport and deposition of sand in the lake and around the channel connecting it to the sea. Tsunamis from the 684 Tenmu, 1361 Shokei, and 1707 Hoei <span class="hlt">earthquakes</span> deposited sand in Ryujin Lake and around the channel connecting it to the sea, but lesser tsunamis from other <span class="hlt">earthquakes</span> were unable to reach Ryujin Lake. This irregular behavior suggests that in addition to the regular Nankai Trough <span class="hlt">earthquake</span> cycle of 100-150 years, there is a hyperearthquake cycle of 300-500 years. These greater <span class="hlt">earthquakes</span> produce the largest tsunamis from western Shikoku to Kyushu.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhDT.......112A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhDT.......112A"><span><span class="hlt">Earthquake</span>-Soil-Structure Interaction <span class="hlt">Modeling</span> of Nuclear Power Plants for Near-Field Events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Abell Mena, Jose Antonio</p> <p></p> <p>This dissertation proposes an approach to <span class="hlt">modeling</span> the response of a nuclear power facility considering soil-structure interaction, when subjected to <span class="hlt">earthquake</span> motions originated in the near-field. It is argued that near-field <span class="hlt">earthquake</span>-induced motions are complex in the sense that current state-of-practice assumptions made on the nature of seismic wave-field stemming from such events are oversimplified. Furthermore, even if near-field sources might not deliver the largest magnitude <span class="hlt">earthquakes</span> for a given seismic setting, it is possible that the intensity of motions generated by such sources controls design of structural and/or non-structural components of nuclear facilities in some frequency range. Several nuclear power facilities are located in the vicinity of known smaller <span class="hlt">earthquake</span> sources (within less than 10km). The domain reduction method is used to excite a <span class="hlt">model</span> of the soil-structure system with a three-dimensional seismic wave-field which is computed using a state-of-the-art seismic simulation code. The response of this <span class="hlt">model</span> is compared with that of an alternative <span class="hlt">model</span> which assumes that the incoming wave-field is not three-dimensional but unidimensional. This last <span class="hlt">modeling</span> approach is the most common in both the research and practice of nuclear power-plant seismic design. Two source-to-site geometries are evaluated to compare possible effects of the propagation path. Computation of non-linear soil response is achieved by using a new implementation of the classical elasto-plasticity constitutive <span class="hlt">modeling</span> framework using the new language features of the C++11 standard. This novel implementation scheme aims at being both efficient and maintainable by software-engineering standards. Both these goals are hard to achieve with just the features of previous editions of the C++ standard.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.S53C..03C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.S53C..03C"><span>Using a Global Search Inversion to Constrain <span class="hlt">Earthquake</span> Kinematic Rupture History and to Assess <span class="hlt">Model</span> Uncertainty</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cirella, A.; Piatanesi, A.; Spudich, P.; Cocco, M.; Tinti, E.</p> <p>2007-12-01</p> <p>We use a two-stage nonlinear technique to invert strong motions records and geodetic data to retrieve the rupture history of an <span class="hlt">earthquake</span> on a finite fault. The unknown <span class="hlt">model</span> parameters, spatially variable peak slip velocity, slip direction, rupture time and rise time, are given at the vertices of subfaults, whereas the parameters within a subfault can vary through a bilinear interpolation of the vertex values. The forward <span class="hlt">modeling</span> is performed with a discrete wavenumber technique, whose Green's functions include the complete response of the vertically varying non-attenuating Earth structure. The GPS coseismic data are compared with the synthetic displacements using a L2 norm, while the recorded and <span class="hlt">modeled</span> waveforms are compared in the frequency domain, using a cost function that is a hybrid representation between L1 and L2 norms. During the first stage (search), an algorithm based on heat-bath simulated annealing generates an ensemble of <span class="hlt">models</span> that efficiently sample the good data-fitting regions of the parameter space. During this stage multiple Earth structures can be used to allow for uncertainty in the true structure. In the second stage (appraisal), the algorithm performs a statistical analysis of the <span class="hlt">model</span> ensemble and computes a weighted mean <span class="hlt">model</span> and its standard deviation by weighting all <span class="hlt">models</span> by the inverse of the cost function values. We do not use any smoothing operator. This technique, rather than simply looking at the best <span class="hlt">model</span>, extracts the most stable features of the <span class="hlt">earthquake</span> rupture that are consistent with the data and gives an estimate of the variability of each <span class="hlt">model</span> parameter. We present some applications to recent <span class="hlt">earthquakes</span> such as the 2000 western Tottori (Mw 6.7) and the 2007 Niigata (Mw 6.6) (Japan) <span class="hlt">earthquakes</span> in order to test and show the effectiveness of the method. Our methodology allows the use of different slip velocity time functions and we emphasize the relevance of adopting source time functions in kinematic inversions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://earthquake.usgs.gov/learn/facts.php','NIH-MEDLINEPLUS'); return false;" href="https://earthquake.usgs.gov/learn/facts.php"><span><span class="hlt">Earthquake</span> Facts</span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>... landslide (usually triggered by an <span class="hlt">earthquake</span>) displacing the ocean water. The hypocenter of an <span class="hlt">earthquake</span> is the ... is the zone of <span class="hlt">earthquakes</span> surrounding the Pacific Ocean — about 90% of the world’s <span class="hlt">earthquakes</span> occur ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70160542','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70160542"><span>Non-linear resonant coupling of tsunami edge waves using stochastic <span class="hlt">earthquake</span> source <span class="hlt">models</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>Geist, Eric L.</p> <p>2016-01-01</p> <p>Non-linear resonant coupling of edge waves can occur with tsunamis generated by large-magnitude subduction zone <span class="hlt">earthquakes</span>. <span class="hlt">Earthquake</span> rupture zones that straddle beneath the coastline of continental margins are particularly efficient at generating tsunami edge waves. Using a stochastic <span class="hlt">model</span> for <span class="hlt">earthquake</span> slip, it is shown that a wide range of edge-wave modes and wavenumbers can be excited, depending on the variability of slip. If two modes are present that satisfy resonance conditions, then a third mode can gradually increase in amplitude over time, even if the <span class="hlt">earthquake</span> did not originally excite that edge-wave mode. These three edge waves form a resonant triad that can cause unexpected variations in tsunami amplitude long after the first arrival. An M ∼ 9, 1100 km-long continental subduction zone <span class="hlt">earthquake</span> is considered as a test case. For the least-variable slip examined involving a Gaussian random variable, the dominant resonant triad includes a high-amplitude fundamental mode wave with wavenumber associated with the along-strike dimension of rupture. The two other waves that make up this triad include subharmonic waves, one of fundamental mode and the other of mode 2 or 3. For the most variable slip examined involving a Cauchy-distributed random variable, the dominant triads involve higher wavenumbers and modes because subevents, rather than the overall rupture dimension, control the excitation of edge waves. Calculation of the resonant period for energy transfer determines which cases resonant coupling may be instrumentally observed. For low-mode triads, the maximum transfer of energy occurs approximately 20–30 wave periods after the first arrival and thus may be observed prior to the tsunami coda being completely attenuated. Therefore, under certain circumstances the necessary ingredients for resonant coupling of tsunami edge waves exist, indicating that resonant triads may be observable and implicated in late, large-amplitude tsunami arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T53B..01R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T53B..01R"><span>Surface Deformation Associated with the 1983 Borah Peak <span class="hlt">Earthquake</span> Measured from Digital Surface <span class="hlt">Model</span> Differencing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reitman, N. G.; Briggs, R.; Gold, R. D.; DuRoss, C. B.</p> <p>2015-12-01</p> <p>Post-<span class="hlt">earthquake</span>, field-based assessments of surface displacement commonly underestimate offsets observed with remote sensing techniques (e.g., InSAR, image cross-correlation) because they fail to capture the total deformation field. Modern <span class="hlt">earthquakes</span> are readily characterized by comparing pre- and post-event remote sensing data, but historical <span class="hlt">earthquakes</span> often lack pre-event data. To overcome this challenge, we use historical aerial photographs to derive pre-event digital surface <span class="hlt">models</span> (DSMs), which we compare to modern, post-event DSMs. Our case study focuses on resolving on- and off-fault deformation along the Lost River fault that accompanied the 1983 M6.9 Borah Peak, Idaho, normal-faulting <span class="hlt">earthquake</span>. We use 343 aerial images from 1952-1966 and vertical control points selected from National Geodetic Survey benchmarks measured prior to 1983 to construct a pre-event point cloud (average ~ 0.25 pts/m2) and corresponding DSM. The post-event point cloud (average ~ 1 pt/m2) and corresponding DSM are derived from WorldView 1 and 2 scenes processed with NASA's Ames Stereo Pipeline. The point clouds and DSMs are coregistered using vertical control points, an iterative closest point algorithm, and a DSM coregistration algorithm. Preliminary results of differencing the coregistered DSMs reveal a signal spanning the surface rupture that is consistent with tectonic displacement. Ongoing work is focused on quantifying the significance of this signal and error analysis. We expect this technique to yield a more complete understanding of on- and off-fault deformation patterns associated with the Borah Peak <span class="hlt">earthquake</span> along the Lost River fault and to help improve assessments of surface deformation for other historical ruptures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204..878G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204..878G"><span>Non-linear resonant coupling of tsunami edge waves using stochastic <span class="hlt">earthquake</span> source <span class="hlt">models</span></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.</p> <p>2016-02-01</p> <p>Non-linear resonant coupling of edge waves can occur with tsunamis generated by large-magnitude subduction zone <span class="hlt">earthquakes</span>. <span class="hlt">Earthquake</span> rupture zones that straddle beneath the coastline of continental margins are particularly efficient at generating tsunami edge waves. Using a stochastic <span class="hlt">model</span> for <span class="hlt">earthquake</span> slip, it is shown that a wide range of edge-wave modes and wavenumbers can be excited, depending on the variability of slip. If two modes are present that satisfy resonance conditions, then a third mode can gradually increase in amplitude over time, even if the <span class="hlt">earthquake</span> did not originally excite that edge-wave mode. These three edge waves form a resonant triad that can cause unexpected variations in tsunami amplitude long after the first arrival. An M ˜ 9, 1100 km-long continental subduction zone <span class="hlt">earthquake</span> is considered as a test case. For the least-variable slip examined involving a Gaussian random variable, the dominant resonant triad includes a high-amplitude fundamental mode wave with wavenumber associated with the along-strike dimension of rupture. The two other waves that make up this triad include subharmonic waves, one of fundamental mode and the other of mode 2 or 3. For the most variable slip examined involving a Cauchy-distributed random variable, the dominant triads involve higher wavenumbers and modes because subevents, rather than the overall rupture dimension, control the excitation of edge waves. Calculation of the resonant period for energy transfer determines which cases resonant coupling may be instrumentally observed. For low-mode triads, the maximum transfer of energy occurs approximately 20-30 wave periods after the first arrival and thus may be observed prior to the tsunami coda being completely attenuated. Therefore, under certain circumstances the necessary ingredients for resonant coupling of tsunami edge waves exist, indicating that resonant triads may be observable and implicated in late, large-amplitude tsunami arrivals.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhDT........65C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhDT........65C"><span>Using GPS to Rapidly Detect and <span class="hlt">Model</span> <span class="hlt">Earthquakes</span> and Transient Deformation Events</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Crowell, Brendan W.</p> <p></p> <p>The rapid <span class="hlt">modeling</span> and detection of <span class="hlt">earthquakes</span> and transient deformation is a problem of extreme societal importance for <span class="hlt">earthquake</span> early warning and rapid hazard response. To date, GPS data is not used in <span class="hlt">earthquake</span> early warning or rapid source <span class="hlt">modeling</span> even in Japan or California where the most extensive geophysical networks exist. This dissertation focuses on creating algorithms for automated <span class="hlt">modeling</span> of <span class="hlt">earthquakes</span> and transient slip events using GPS data in the western United States and Japan. First, I focus on the creation and use of high-rate GPS and combined seismogeodetic data for applications in <span class="hlt">earthquake</span> early warning and rapid slip inversions. Leveraging data from <span class="hlt">earthquakes</span> in Japan and southern California, I demonstrate that an accurate magnitude estimate can be made within seconds using P wave displacement scaling, and that a heterogeneous static slip <span class="hlt">model</span> can be generated within 2-3 minutes. The preliminary source characterization is sufficiently robust to independently confirm the extent of fault slip used for rapid assessment of strong ground motions and improved tsunami warning in subduction zone environments. Secondly, I investigate the automated detection of transient slow slip events in Cascadia using daily positional estimates from GPS. Proper geodetic characterization of transient deformation is necessary for studies of regional interseismic, coseismic and postseismic tectonics, and miscalculations can affect our understanding of the regional stress field. I utilize the relative strength index (RSI) from financial forecasting to create a complete record of slow slip from continuous GPS stations in the Cascadia subduction zone between 1996 and 2012. I create a complete history of slow slip across the Cascadia subduction zone, fully characterizing the timing, progression, and magnitude of events. Finally, using a combination of continuous and campaign GPS measurements, I characterize the amount of extension, shear and subsidence in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S22A..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S22A..04C"><span>Triggering processes of <span class="hlt">earthquake</span> bursts in Japan: evidence from statistical <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, X.; Kato, A.</p> <p>2013-12-01</p> <p>We search for spatial-temporal isolated <span class="hlt">earthquake</span> bursts across Japan using the JMA catalog from 2000 to 2013. For each identified burst, we obtain a set of parameters, which include: Δσquasi (ratio between total moment release and volume of the burst), tmax, duration, radius, planarity and dip. A total of 290 bursts are identified, and 90 bursts exhibit 'repeating-like' feature: they tend to occur within 2 km of at least one other burst. Bursts with tmax ≥ 0.05 exhibit significantly longer duration and lower Δσquasi. To understand the temporal evolution of possible external stressing rate change, we select 18 areas through examination of 'repeating' bursts, and apply ETAS <span class="hlt">model</span> to all <span class="hlt">earthquakes</span> in each area with magnitude ≥ Mc (local). We compare <span class="hlt">models</span> with constant background seismicity rate μ0 and time varying μ(t), the latter general produce higher likelihood (better fit to observations). All the 18 areas feature high background seismicity fraction, ranging from 37% to 91%. Variations in background seismicity rate range 1-to-4 orders of magnitude. Increased aftershock productivity α (range from 0.9 to 1.5) is generally observed for <span class="hlt">models</span> with μ(t). For <span class="hlt">earthquakes</span> within the Izu-Tobu volcanic area and during the 2000 Miyakijima eruption, extremely fast Omori's-law aftershock decay (p > 3) and high background fraction (≥ 90%) are observed. Seismicity in the two areas is almost entirely related to dike intrusion processes with very little <span class="hlt">earthquake</span> interaction, and the high p-value may relate to the strong stress heterogeneity or temperature. The background seismicity rates in the 18 areas are usually superimposition of smooth-shaped slow transient process and pulse-like sudden onset with exponential decay. For comparison, we obtain ETAS parameters for six shallow crustal mainshock-aftershock sequences with Mw ≥ 6.5, and include <span class="hlt">earthquakes</span> prior to mainshocks for <span class="hlt">modeling</span>. These sequences all feature higher aftershock productivity (α>2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.S22A..04C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.S22A..04C"><span>Triggering processes of <span class="hlt">earthquake</span> bursts in Japan: evidence from statistical <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cramer, C. H.; Boyd, O. S.</p> <p>2011-12-01</p> <p>We search for spatial-temporal isolated <span class="hlt">earthquake</span> bursts across Japan using the JMA catalog from 2000 to 2013. For each identified burst, we obtain a set of parameters, which include: Δσquasi (ratio between total moment release and volume of the burst), tmax, duration, radius, planarity and dip. A total of 290 bursts are identified, and 90 bursts exhibit 'repeating-like' feature: they tend to occur within 2 km of at least one other burst. Bursts with tmax ≥ 0.05 exhibit significantly longer duration and lower Δσquasi. To understand the temporal evolution of possible external stressing rate change, we select 18 areas through examination of 'repeating' bursts, and apply ETAS <span class="hlt">model</span> to all <span class="hlt">earthquakes</span> in each area with magnitude ≥ Mc (local). We compare <span class="hlt">models</span> with constant background seismicity rate μ0 and time varying μ(t), the latter general produce higher likelihood (better fit to observations). All the 18 areas feature high background seismicity fraction, ranging from 37% to 91%. Variations in background seismicity rate range 1-to-4 orders of magnitude. Increased aftershock productivity α (range from 0.9 to 1.5) is generally observed for <span class="hlt">models</span> with μ(t). For <span class="hlt">earthquakes</span> within the Izu-Tobu volcanic area and during the 2000 Miyakijima eruption, extremely fast Omori's-law aftershock decay (p > 3) and high background fraction (≥ 90%) are observed. Seismicity in the two areas is almost entirely related to dike intrusion processes with very little <span class="hlt">earthquake</span> interaction, and the high p-value may relate to the strong stress heterogeneity or temperature. The background seismicity rates in the 18 areas are usually superimposition of smooth-shaped slow transient process and pulse-like sudden onset with exponential decay. For comparison, we obtain ETAS parameters for six shallow crustal mainshock-aftershock sequences with Mw ≥ 6.5, and include <span class="hlt">earthquakes</span> prior to mainshocks for <span class="hlt">modeling</span>. These sequences all feature higher aftershock productivity (α>2</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NHESS..16...55V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NHESS..16...55V"><span>A detailed seismic zonation <span class="hlt">model</span> for shallow <span class="hlt">earthquakes</span> in the broader Aegean area</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vamvakaris, D. A.; Papazachos, C. B.; Papaioannou, Ch. A.; Scordilis, E. M.; Karakaisis, G. F.</p> <p>2016-01-01</p> <p>In the present work we propose a new seismic zonation <span class="hlt">model</span> of area type sources for the broader Aegean area, which can be readily used for seismic hazard assessment. The definition of this <span class="hlt">model</span> is based not only on seismicity information but incorporates all available seismotectonic and neotectonic information for the study area, in an attempt to define zones which show not only a rather homogeneous seismicity release but also exhibit similar active faulting characteristics. For this reason, all available seismological information such as fault plane solutions and the corresponding kinematic axes have been incorporated in the analysis, as well as information about active tectonics, such as seismic and active faults. Moreover, various morphotectonic features (e.g. relief, coastline) were also considered. Finally, a revised seismic catalogue is employed and <span class="hlt">earthquake</span> epicentres since historical times (550 BC-2008) are employed, in order to define areas of common seismotectonic characteristics, that could constitute a discrete seismic zone. A new revised <span class="hlt">model</span> of 113 <span class="hlt">earthquake</span> seismic zones of shallow <span class="hlt">earthquakes</span> for the broader Aegean area is finally proposed. Using the proposed zonation <span class="hlt">model</span>, a detailed study is performed for the catalogue completeness for the recent instrumental period.Using the defined completeness information, seismicity parameters (such as G-R values) for the 113 new seismic zones have been calculated, and their spatial distribution was also examined. The spatial variation of the obtained b values shows an excellent correlation with the geotectonic setting in the area, in good agreement with previous studies. Moreover, a quantitative estimation of seismicity is performed in terms of the mean return period, T<i/>m, of large (M ≥ 6.0) <span class="hlt">earthquakes</span>, as well as the most frequent maximum magnitude, M<i/>t, for a typical time period (T = 50 yr), revealing significant spatial variations of seismicity levels within the study area. The new proposed</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8345E..0QH','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8345E..0QH"><span>Experimental validation of finite element <span class="hlt">model</span> analysis of a steel frame in simulated post-<span class="hlt">earthquake</span> fire environments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huang, Ying; Bevans, W. J.; Xiao, Hai; Zhou, Zhi; Chen, Genda</p> <p>2012-04-01</p> <p>During or after an <span class="hlt">earthquake</span> event, building system often experiences large strains due to shaking effects as observed during recent <span class="hlt">earthquakes</span>, causing permanent inelastic deformation. In addition to the inelastic deformation induced by the <span class="hlt">earthquake</span> effect, the post-<span class="hlt">earthquake</span> fires associated with short fuse of electrical systems and leakage of gas devices can further strain the already damaged structures during the <span class="hlt">earthquakes</span>, potentially leading to a progressive collapse of buildings. Under these harsh environments, measurements on the involved building by various sensors could only provide limited structural health information. Finite element <span class="hlt">model</span> analysis, on the other hand, if validated by predesigned experiments, can provide detail structural behavior information of the entire structures. In this paper, a temperature dependent nonlinear 3-D finite element <span class="hlt">model</span> (FEM) of a one-story steel frame is set up by ABAQUS based on the cited material property of steel from EN 1993-1.2 and AISC manuals. The FEM is validated by testing the <span class="hlt">modeled</span> steel frame in simulated post-<span class="hlt">earthquake</span> environments. Comparisons between the FEM analysis and the experimental results show that the FEM predicts the structural behavior of the steel frame in post-<span class="hlt">earthquake</span> fire conditions reasonably. With experimental validations, the FEM analysis of critical structures could be continuously predicted for structures in these harsh environments for a better assistant to fire fighters in their rescue efforts and save fire victims.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70003681','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70003681"><span><span class="hlt">Model</span> and parametric uncertainty in source-based kinematic <span class="hlt">models</span> of <span class="hlt">earthquake</span> ground motion</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, Stephen; Frankel, Arthur; Liu, Pengcheng; Zeng, Yuehua; Rahman, Shariftur</p> <p>2011-01-01</p> <p>Four independent ground-motion simulation codes are used to <span class="hlt">model</span> the strong ground motion for three <span class="hlt">earthquakes</span>: 1994 Mw 6.7 Northridge, 1989 Mw 6.9 Loma Prieta, and 1999 Mw 7.5 Izmit. These 12 sets of synthetics are used to make estimates of the variability in ground-motion predictions. In addition, ground-motion predictions over a grid of sites are used to estimate parametric uncertainty for changes in rupture velocity. We find that the combined <span class="hlt">model</span> uncertainty and random variability of the simulations is in the same range as the variability of regional empirical ground-motion data sets. The majority of the standard deviations lie between 0.5 and 0.7 natural-log units for response spectra and 0.5 and 0.8 for Fourier spectra. The estimate of <span class="hlt">model</span> epistemic uncertainty, based on the different <span class="hlt">model</span> predictions, lies between 0.2 and 0.4, which is about one-half of the estimates for the standard deviation of the combined <span class="hlt">model</span> uncertainty and random variability. Parametric uncertainty, based on variation of just the average rupture velocity, is shown to be consistent in amplitude with previous estimates, showing percentage changes in ground motion from 50% to 300% when rupture velocity changes from 2.5 to 2.9 km/s. In addition, there is some evidence that mean biases can be reduced by averaging ground-motion estimates from different methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1714559S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1714559S"><span>A post-seismic deformation <span class="hlt">model</span> after the 2010 <span class="hlt">earthquakes</span> in Latin America</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sánchez, Laura; Drewes, Hermann; Schmidt, Michael</p> <p>2015-04-01</p> <p>The Maule 2010 <span class="hlt">earthquake</span> in Chile generated the largest displacements of geodetic observation stations ever observed in terrestrial reference systems. Coordinate changes came up to 4 meters, and deformations were measurable in distances up to more than 1000 km from the epicentre. The station velocities in the regions adjacent to the epicentre changed dramatically after the seism; while they were oriented eastward with approximately 2 cm/year before the event, they are now directed westward with about 1 cm/year. The 2010 Baja California <span class="hlt">earthquake</span> in Mexico produced displacements in the decimetre level also followed by anomalous velocity changes. The main problem in geodetic applications is that there is no reliable reference system to be used practically in the region. For geophysical applications we have to redefine the tectonic structure in South America. The area south of 35° S … 40° S was considered as a stable part of the South American plate. Now we see that there are large and extended crustal deformations. The paper presents a new multi-year velocity <span class="hlt">model</span> computed from the Geocentric Reference System of the Americas (SIRGAS) including only the four years after the seismic events (mid-2010 … mid-2014). These velocities are used to derive a continuous deformation <span class="hlt">model</span> of the entire Latin American region from Mexico to Tierra de Fuego. The <span class="hlt">model</span> is compared with the same velocity <span class="hlt">model</span> for SIRGAS (VEMOS2009) before the <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PApGe.171.3421B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PApGe.171.3421B"><span>Observations and <span class="hlt">Modeling</span> of the August 27, 2012 <span class="hlt">Earthquake</span> and Tsunami affecting El Salvador and Nicaragua</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Borrero, Jose C.; Kalligeris, Nikos; Lynett, Patrick J.; Fritz, Hermann M.; Newman, Andrew V.; Convers, Jaime A.</p> <p>2014-12-01</p> <p>On 27 August 2012 (04:37 UTC, 26 August 10:37 p.m. local time) a magnitude M w = 7.3 <span class="hlt">earthquake</span> occurred off the coast of El Salvador and generated surprisingly large local tsunami. Following the event, local and international tsunami teams surveyed the tsunami effects in El Salvador and northern Nicaragua. The tsunami reached a maximum height of ~6 m with inundation of up to 340 m inland along a 25 km section of coastline in eastern El Salvador. Less severe inundation was reported in northern Nicaragua. In the far-field, the tsunami was recorded by a DART buoy and tide gauges in several locations of the eastern Pacific Ocean but did not cause any damage. The field measurements and recordings are compared to numerical <span class="hlt">modeling</span> results using initial conditions of tsunami generation based on finite-fault <span class="hlt">earthquake</span> and tsunami inversions and a uniform slip <span class="hlt">model</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1916671M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1916671M"><span>Dynamic Rupture <span class="hlt">Model</span> of the 2004 Sumatra-Andaman Megathrust <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>Madden, Elizabeth H.; Ulrich, Thomas; Gabriel, Alice-Agnes</p> <p>2017-04-01</p> <p>The M 9.1-9.3 Sumatra-Andaman <span class="hlt">earthquake</span> of 26 December 2004 caused violent shaking and generated a tsunami wave that was up to 50 m high along the northern coast of Sumatra. While various finite-source <span class="hlt">models</span> have been proposed, here we present a physically realistic dynamic rupture <span class="hlt">model</span> of the megathrust <span class="hlt">earthquake</span>. To accomplish this, we use SeisSol, a highly parallelized software package that runs on modern supercomputers. Numerically, it follows an ADER-DG scheme to solve the spontaneous dynamic <span class="hlt">earthquake</span> rupture problem with high-order accuracy in space and time. SeisSol accommodates unstructured tetrahedral meshes that decrease computational expense by allowing for a high-resolution mesh where required, including along the non-planar subducting fault and to capture the bathymetry, as well as a lower resolution mesh in other regions. In the SeisSol <span class="hlt">model</span>, the slip interface follows the geometry of Slab1.0 to the south and aftershock locations to the north. 4 km resolution bathymetry from GEBCO is incorporated at the ocean floor. Material properties are taken from Crust1.0 and are laterally homogeneous, but vertically varying. The <span class="hlt">model</span> results are constrained by the overall characteristics of the rupture, including the magnitude, propagation speed, and extent along strike, as well as surface displacements recorded with GPS satellites. We aim to resolve the influence of source dynamics on ground displacement and the potential impacts on tsunami generation in the framework of the ASCETE project ("Advanced Simulation of Coupled <span class="hlt">Earthquake</span> and Tsunami Events", www.ascete.de).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23D..02G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23D..02G"><span>Using Inundation and Sediment Transport <span class="hlt">Modeling</span> To Characterize <span class="hlt">Earthquake</span> Source Parameters from Tsunami Deposits</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gelfenbaum, G. R.; La Selle, S.; Witter, R. C.; Sugawara, D.; Jaffe, B. E.</p> <p>2015-12-01</p> <p>Inferring the relative magnitude of tsunamis generated during <span class="hlt">earthquakes</span> based on the characteristics of sandy coastal deposits is a challenging problem. Using a hydrodynamic and sediment transport <span class="hlt">model</span>, we explore whether the volume of sandy tsunami deposits can be used to infer tsunami magnitude and seafloor deformation. For large subduction zone <span class="hlt">earthquakes</span> specifically, we are testing the hypothesis that onshore tsunami deposit volume is correlated with nearshore tsunami wave height and coseismic slip. First, we test this hypothesis using onshore tsunami deposit volume data and offshore slip for the 2011 Tohoku <span class="hlt">earthquake</span> and tsunami. This test considers tsunami deposit volume and offshore slip as they vary alongshore across a wide range of sediment sources, offshore and onshore slopes, and boundary roughness conditions. Preliminary analysis suggests that a strong correlation exists between onshore tsunami deposit volume and adjacent offshore coseismic slip, so long as ample sediment were available along the coast to be eroded. Second, we apply a Delft3D tsunami inundation and sediment transport <span class="hlt">model</span> to Stardust Bay in the U.S. Aleutian Islands, where 6 tsunamis in the last ~1700 years deposited marine sand across a coastal plain as much as 800 m inland and up to ~15 m above mean sea level. The youngest sand sheet, probably deposited by a tsunami generated during the 1957 Andreanof Islands <span class="hlt">earthquake</span> (Mw 8.6), has the smallest sediment volume. Several older deposits have larger volumes. <span class="hlt">Models</span> show that ≥10 m of slip on the Aleutian subduction megathrust offshore of Stardust Bay could produce the onshore sediment volume measured for the 1957 deposit. Older tsunami deposits of greater volume require up to 14 m of megathrust slip. <span class="hlt">Model</span> sensitivity studies show that onshore sediment volume is most sensitive to megathrust slip and less sensitive to other unknowns such as width of fault rupture and roughness of inundated terrain</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.osti.gov/scitech/biblio/5014998','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5014998"><span>Equivalent strike-slip <span class="hlt">earthquake</span> cycles in half-space and lithosphere-asthenosphere Earth <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Savage, J.C. )</p> <p>1990-04-10</p> <p>By virtue of the images used in the dislocation solution, the deformation at the free surface produced throughout the <span class="hlt">earthquake</span> cycle by slippage on a long strike-slip fault in an Earth <span class="hlt">model</span> consisting of an elastic plate (lithosphere) overlying a visoelastic half-space (asthenosphere) can be duplicated by prescribed slip on a vertical fault embedded in an elastic half-space. For the case in which each <span class="hlt">earthquake</span> ruptures the entire lithosphere (thickness H), the half-space equivalent slip rate is as follows: Depth interval 0-H, slip identical to that in lithosphere-asthenosphere <span class="hlt">model</span> (i.e., abrupt coseismic slip and no subsequent slip); depth interval (2n {minus} 1) H to (2n + 1) H (n = 1,2,...), slip rate uniform in space and dependent upon time as F{sub n}(t) exp ({minus}t/{tau}) where F{sub n} is a (n {minus} 1) degree polynomial in t, {tau} is twice the asthenosphere relaxation time, and t is measured from the instant after the preceding <span class="hlt">earthquake</span>. The slip rate averaged over the seismic cycle in each depth interval equals the secular rate of relative plate motion. The surface deformation due to the <span class="hlt">earthquake</span> cycle in the lithosphere-asthenosphere <span class="hlt">model</span> can be calculated very simply from the half-space <span class="hlt">model</span> with time-dependent slip in the two depth intervals H-3H and 3H-5H, and uniform slip at a rate equal to the secular relative plate velocity below depth 5H. Inversion of 1973-1988 geodetic measurements of deformation across the segment of the San Andrea fault in the Transverse Ranges north of Los Angeles for the half-space equivalent slip distribution suggests no significant slip on the fault above 30 km and a uniform slip rate of 36 mm/yr below 30 km.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815547P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815547P"><span>Numerical <span class="hlt">model</span> of the glacially-induced intraplate <span class="hlt">earthquakes</span> and faults formation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Petrunin, Alexey; Schmeling, Harro</p> <p>2016-04-01</p> <p>According to the plate tectonics, main <span class="hlt">earthquakes</span> are caused by moving lithospheric plates and are located mainly at plate boundaries. However, some of significant seismic events may be located far away from these active areas. The nature of the intraplate <span class="hlt">earthquakes</span> remains unclear. It is assumed, that the triggering of seismicity in the eastern Canada and northern Europe might be a result of the glacier retreat during a glacial-interglacial cycle (GIC). Previous numerical <span class="hlt">models</span> show that the impact of the glacial loading and following isostatic adjustment is able to trigger seismicity in pre-existing faults, especially during deglaciation stage. However this <span class="hlt">models</span> do not explain strong glaciation-induced historical <span class="hlt">earthquakes</span> (M5-M7). Moreover, numerous studies report connection of the location and age of major faults in the regions undergone by glaciation during last glacial maximum with the glacier dynamics. This probably imply that the GIC might be a reason for the fault system formation. Our numerical <span class="hlt">model</span> provides analysis of the strain-stress evolution during the GIC using the finite volume approach realised in the numerical code Lapex 2.5D which is able to operate with large strains and visco-elasto-plastic rheology. To simulate self-organizing faults, the damage rheology <span class="hlt">model</span> is implemented within the code that makes possible not only visualize faulting but also estimate energy release during the seismic cycle. The <span class="hlt">modeling</span> domain includes two-layered crust, lithospheric mantle and the asthenosphere that makes possible simulating elasto-plastic response of the lithosphere to the glaciation-induced loading (unloading) and viscous isostatic adjustment. We have considered three scenarios for the <span class="hlt">model</span>: horizontal extension, compression and fixed boundary conditions. <span class="hlt">Modeling</span> results generally confirm suppressing seismic activity during glaciation phases whereas retreat of a glacier triggers <span class="hlt">earthquakes</span> for several thousand years. Tip of the glacier</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004GMS...150..335J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004GMS...150..335J"><span><span class="hlt">Earthquake</span> Prediction 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>Jackson, David D.</p> <p></p> <p>Prospects for <span class="hlt">earthquake</span> prediction and forecasting, and even their definitions, are actively debated. Here, "forecasting" means estimating the future <span class="hlt">earthquake</span> rate as a function of location, time, and magnitude. Forecasting becomes "prediction" when we identify special conditions that make the immediate probability much higher than usual and high enough to justify exceptional action. Proposed precursors run from aeronomy to zoology, but no identified phenomenon consistently precedes <span class="hlt">earthquakes</span>. The reported prediction of the 1975 Haicheng, China <span class="hlt">earthquake</span> is often proclaimed as the most successful, but the success is questionable. An <span class="hlt">earthquake</span> predicted to occur near Parkfield, California in 1988±5 years has not happened. Why is prediction so hard? <span class="hlt">Earthquakes</span> start in a tiny volume deep within an opaque medium; we do not know their boundary conditions, initial conditions, or material properties well; and <span class="hlt">earthquake</span> precursors, if any, hide amongst unrelated anomalies. <span class="hlt">Earthquakes</span> cluster in space and time, and following a quake <span class="hlt">earthquake</span> probability spikes. Aftershocks illustrate this clustering, and later <span class="hlt">earthquakes</span> may even surpass earlier ones in size. However, the main shock in a cluster usually comes first and causes the most damage. Specific <span class="hlt">models</span> help reveal the physics and allow intelligent disaster response. <span class="hlt">Modeling</span> stresses from past <span class="hlt">earthquakes</span> may improve forecasts, but this approach has not yet been validated prospectively. Reliable prediction of individual quakes is not realistic in the foreseeable future, but probabilistic forecasting provides valuable information for reducing risk. Recent studies are also leading to exciting discoveries about <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20813636','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20813636"><span>A <span class="hlt">nonconservative</span> Lagrangian framework for statistical fluid registration-SAFIRA.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brun, Caroline C; Lepore, Natasha; Pennec, Xavier; Chou, Yi-Yu; Lee, Agatha D; de Zubicaray, Greig; McMahon, Katie L; Wright, Margaret J; Gee, James C; Thompson, Paul M</p> <p>2011-02-01</p> <p>In this paper, we used a <span class="hlt">nonconservative</span> Lagrangian mechanics approach to formulate a new statistical algorithm for fluid registration of 3-D brain images. This algorithm is named SAFIRA, acronym for statistically-assisted fluid image registration algorithm. A nonstatistical version of this algorithm was implemented , where the deformation was regularized by penalizing deviations from a zero rate of strain. In , the terms regularizing the deformation included the covariance of the deformation matrices (Σ) and the vector fields (q) . Here, we used a Lagrangian framework to reformulate this algorithm, showing that the regularizing terms essentially allow <span class="hlt">nonconservative</span> work to occur during the flow. Given 3-D brain images from a group of subjects, vector fields and their corresponding deformation matrices are computed in a first round of registrations using the nonstatistical implementation. Covariance matrices for both the deformation matrices and the vector fields are then obtained and incorporated (separately or jointly) in the <span class="hlt">nonconservative</span> terms, creating four versions of SAFIRA. We evaluated and compared our algorithms' performance on 92 3-D brain scans from healthy monozygotic and dizygotic twins; 2-D validations are also shown for corpus callosum shapes delineated at midline in the same subjects. After preliminary tests to demonstrate each method, we compared their detection power using tensor-based morphometry (TBM), a technique to analyze local volumetric differences in brain structure. We compared the accuracy of each algorithm variant using various statistical metrics derived from the images and deformation fields. All these tests were also run with a traditional fluid method, which has been quite widely used in TBM studies. The versions incorporating vector-based empirical statistics on brain variation were consistently more accurate than their counterparts, when used for automated volumetric quantification in new brain images. This suggests the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.8782A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.8782A"><span>Dynamic <span class="hlt">modeling</span> of normal faults of the 2016 Central Italy <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>Aochi, Hideo</p> <p>2017-04-01</p> <p>The <span class="hlt">earthquake</span> sequence of the Central Italy in 2016 are characterized mainly by the Mw6.0 24th August, Mw5.9 26th October and Mw6.4 30th October as well as two Mw5.4 <span class="hlt">earthquakes</span> (24th August, 26th October) (catalogue INGV). They all show normal faulting mechanisms corresponding to the Apennines's tectonics. They are aligned briefly along NNW-SSE axis, and they may not be on a single continuous fault plane. Therefore, dynamic rupture <span class="hlt">modeling</span> of sequences should be carried out supposing co-planar normal multiple segments. We apply a Boundary Domain Method (BDM, Goto and Bielak, GJI, 2008) coupling a boundary integral equation method and a domain-based method, namely a finite difference method in this study. The Mw6.0 24th August <span class="hlt">earthquake</span> is <span class="hlt">modeled</span>. We use the basic information of hypocenter position, focal mechanism and potential ruptured dimension from the INGV catalogue and Tinti et al., GRL, 2016), and begin with a simple condition (homogeneous boundary condition). From our preliminary simulations, it is shown that a uniformly extended rupture <span class="hlt">model</span> does not fit the near-field ground motions and localized heterogeneity would be required.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70024568','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70024568"><span>A bilinear source-scaling <span class="hlt">model</span> for M-log a observations of continental <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>Hanks, T.C.; Bakun, W.H.</p> <p>2002-01-01</p> <p>The Wells and Coppersmith (1994) M-log A data set for continental <span class="hlt">earthquakes</span> (where M is moment magnitude and A is fault area) and the regression lines derived from it are widely used in seismic hazard analysis for estimating M, given A. Their relations are well determined, whether for the full data set of all mechanism types or for the subset of strike-slip <span class="hlt">earthquakes</span>. Because the coefficient of the log A term is essentially 1 in both their relations, they are equivalent to constant stress-drop scaling, at least for M ??? 7, where most of the data lie. For M > 7, however, both relations increasingly underestimate the observations with increasing M. This feature, at least for strike-slip <span class="hlt">earthquakes</span>, is strongly suggestive of L-<span class="hlt">model</span> scaling at large M. Using constant stress-drop scaling (???? = 26.7 bars) for M ??? 6.63 and L-<span class="hlt">model</span> scaling (average fault slip u?? = ??L, where L is fault length and ?? = 2.19 × 10-5) at larger M, we obtain the relations M = log A + 3.98 ?? 0.03, A ??? 537 km2 and M = 4/3 log A + 3.07 ?? 0.04, A > 537 km2. These prediction equations of our bilinear <span class="hlt">model</span> fit the Wells and Coppersmith (1994) data set well in their respective ranges of validity, the transition magnitude corresponding to A = 537 km2 being M = 6.71.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70189164','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70189164"><span>A spatiotemporal clustering <span class="hlt">model</span> for the Third Uniform California <span class="hlt">Earthquake</span> Rupture Forecast (UCERF3‐ETAS): Toward an operational <span class="hlt">earthquake</span> forecast</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, Ned; Milner, Kevin R.; Hardebeck, Jeanne L.; Page, Morgan T.; van der Elst, Nicholas; Jordan, Thomas H.; Michael, Andrew J.; Shaw, Bruce E.; Werner, Maximillan J.</p> <p>2017-01-01</p> <p>We, the ongoing Working Group on California <span class="hlt">Earthquake</span> Probabilities, present a spatiotemporal clustering <span class="hlt">model</span> for the Third Uniform California <span class="hlt">Earthquake</span> Rupture Forecast (UCERF3), with the goal being to represent aftershocks, induced seismicity, and otherwise triggered events as a potential basis for operational <span class="hlt">earthquake</span> forecasting (OEF). Specifically, we add an epidemic‐type aftershock sequence (ETAS) component to the previously published time‐independent and long‐term time‐dependent forecasts. This combined <span class="hlt">model</span>, referred to as UCERF3‐ETAS, collectively represents a relaxation of segmentation assumptions, the inclusion of multifault ruptures, an elastic‐rebound <span class="hlt">model</span> for fault‐based ruptures, and a state‐of‐the‐art spatiotemporal clustering component. It also represents an attempt to merge fault‐based forecasts with statistical seismology <span class="hlt">models</span>, such that information on fault proximity, activity rate, and time since last event are considered in OEF. We describe several unanticipated challenges that were encountered, including a need for elastic rebound and characteristic magnitude–frequency distributions (MFDs) on faults, both of which are required to get realistic triggering behavior. UCERF3‐ETAS produces synthetic catalogs of M≥2.5 events, conditioned on any prior M≥2.5 events that are input to the <span class="hlt">model</span>. We evaluate results with respect to both long‐term (1000 year) simulations as well as for 10‐year time periods following a variety of hypothetical scenario mainshocks. Although the results are very plausible, they are not always consistent with the simple notion that triggering probabilities should be greater if a mainshock is located near a fault. Important factors include whether the MFD near faults includes a significant characteristic <span class="hlt">earthquake</span> component, as well as whether large triggered events can nucleate from within the rupture zone of the mainshock. Because UCERF3‐ETAS has many sources of uncertainty, as</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21541382','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21541382"><span><span class="hlt">Nonconservative</span> electric and magnetic optical forces on submicron dielectric particles</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Gomez-Medina, Raquel; Nieto-Vesperinas, Manuel; Saenz, Juan Jose</p> <p>2011-03-15</p> <p>We present a study of the total force on a small lossless dielectric particle, which presents both an electric and magnetic response, in a optical vortex wave field. We show that the force is a simple combination of conservative and <span class="hlt">nonconservative</span> steady forces that can rectify the flow of magnetodielectric particles. In a vortex lattice the electric-magnetic dipolar interaction can spin the particles either in or out of the whirl sites leading to trapping or diffusion. Specifically, we analyze force effects on submicron silicon spheres in the near infrared, proving that the results previously discussed for hypothetical magnetodielectric particles can be observed for these Si particles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.S32A..05M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.S32A..05M"><span><span class="hlt">Modeling</span> and Monitoring for Predictive Simulation of <span class="hlt">Earthquake</span> Generation in the Japan Region</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Matsu'Ura, M.; Noda, A.; Terakawa, T.; Hashimoto, C.; Fukuyama, E.</p> <p>2008-12-01</p> <p>We can regard <span class="hlt">earthquakes</span> as releases of tectonically accumulated elastic strain energy through dynamic fault ruptures. Given this, the entire <span class="hlt">earthquake</span> generation process generally consists of tectonic loading due to relative plate motion, quasi-static rupture nucleation, dynamic rupture propagation and stop, and fault strength recovery. In the 1990s <span class="hlt">earthquake</span> generation physics has made great progress, and so we can now quantitatively describe the entire <span class="hlt">earthquake</span> generation process with coupled nonlinear equations, consisting of a slip-response function that relates fault slip to shear stress change, a fault constitutive law that prescribes shear strength change with fault slip and contact time, and relative plate motion as driving forces. Recently, we completed a physics-based simulation system for the entire <span class="hlt">earthquake</span> generation process in and around Japan, where the four plates of Pacific, North American, Philippine Sea and Eurasian are interacting with each other. The total system consists of three basic simulation <span class="hlt">models</span> for quasi-static stress accumulation, dynamic rupture propagation and seismic wave propagation, developed on a realistic 3- D structure <span class="hlt">model</span>. Then, given past slip histories and present stress states, we can now predict next step seismic/aseismic fault-slip motion through computation with the combined simulation system. We show two examples of the combined simulation for the 1968 Tokachi-oki <span class="hlt">earthquake</span> (Mw=8.2) and the 2003 Tokachi- oki <span class="hlt">earthquake</span> (Mw=8.1). The first example demonstrates that when the stress state is close to a critical level, dynamic rupture develops into a large <span class="hlt">earthquake</span>, but when the stress state is much lower than the critical level, started rupture is not accelerated. The second example demonstrates that we can quantitatively evaluate the strong ground motions produced by potential interplate <span class="hlt">earthquakes</span> through computer simulation, if the realistic plate-interface geometry, fault constitutive parameters and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.8546D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.8546D"><span>Broadband characterization of large subduction <span class="hlt">earthquakes</span> through the combination of coherent rupture imaging and kinematic <span class="hlt">modeling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dionicio, V.; Satriano, C.; Kiraly, E.; Vilotte, J.-P.; Bernard, P.</p> <p>2012-04-01</p> <p>In recent years the seismic observation has made a huge leap forward in terms of coverage and density of recording stations. This instrumental effort has fostered the development of new approaches to the study of the seismic rupture, which can potentially support and complement the classical finite source kinematic <span class="hlt">modeling</span>. The availability of dense seismic arrays makes today possible to image the <span class="hlt">earthquake</span> extended source through the coherent interferometry of the wave radiation emitted during the rupture propagation. One of the advantages of this approach is to deliver images of the source emissivity that do not need a-priori information on the rupture speed or on the fault geometry, while they can constrain these parameters for kinematic inversion. Moreover, coherent interferometry provides intrinsically high frequency images of the rupture, since it works at frequencies that are generally one or two order of magnitudes higher than those used for kinematic slip inversion. The combination and the joint interpretation of coherent imaging and finite source slip <span class="hlt">modeling</span> opens up new perspectives in the study of the rupture processes, in relation to the geometry and the strength of the fault asperities. We effectively combined coherent rupture imaging and kinematic <span class="hlt">modeling</span> for the study of the rupture process of two mega-thrust events: the 2010, Mw 8.8 Maule <span class="hlt">earthquake</span> (Chile) and the 2011, Mw 9.0 Tohoku <span class="hlt">earthquake</span>. The joint analysis of the rupture images shows, for both the <span class="hlt">earthquakes</span>, distinctive patterns in the space-time distribution of high-frequency emissivity and low-frequency coherent slip. We interpret these results in terms of their implications on the geometry and mechanical properties of the subduction interface and the dynamical properties of the rupture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PApGe.172.1305R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PApGe.172.1305R"><span>Postseismic Deformation Following the 2010 El Mayor-Cucapah <span class="hlt">Earthquake</span>: Observations, Kinematic Inversions, and Dynamic <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rollins, Christopher; Barbot, Sylvain; Avouac, Jean-Philippe</p> <p>2015-05-01</p> <p>Due to its location on a transtensional section of the Pacific-North American plate boundary, the Salton Trough is a region featuring large strike-slip <span class="hlt">earthquakes</span> within a regime of shallow asthenosphere, high heat flow, and complex faulting, and so postseismic deformation there may feature enhanced viscoelastic relaxation and afterslip that is particularly detectable at the surface. The 2010 El Mayor-Cucapah <span class="hlt">earthquake</span> was the largest shock in the Salton Trough since 1892 and occurred close to the US-Mexico border, and so the postseismic deformation recorded by the continuous GPS network of southern California provides an opportunity to study the rheology of this region. Three-year postseismic transients extracted from GPS displacement time-series show four key features: (1) 1-2 cm of cumulative uplift in the Imperial Valley and 1 cm of subsidence in the Peninsular Ranges, (2) relatively large cumulative horizontal displacements 150 km from the rupture in the Peninsular Ranges, (3) rapidly decaying horizontal displacement rates in the first few months after the <span class="hlt">earthquake</span> in the Imperial Valley, and (4) sustained horizontal velocities, following the rapid early motions, that were still visibly ongoing 3 years after the <span class="hlt">earthquake</span>. Kinematic inversions show that the cumulative 3-year postseismic displacement field can be well fit by afterslip on and below the coseismic rupture, though these solutions require afterslip with a total moment equivalent to at least a <span class="hlt">earthquake</span> and higher slip magnitudes than those predicted by coseismic stress changes. Forward <span class="hlt">modeling</span> shows that stress-driven afterslip and viscoelastic relaxation in various configurations within the lithosphere can reproduce the early and later horizontal velocities in the Imperial Valley, while Newtonian viscoelastic relaxation in the asthenosphere can reproduce the uplift in the Imperial Valley and the subsidence and large westward displacements in the Peninsular Ranges. We present two forward</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Earthquake&pg=4&id=EJ782558','ERIC'); return false;" href="https://eric.ed.gov/?q=Earthquake&pg=4&id=EJ782558"><span>Redefining <span class="hlt">Earthquakes</span> and the <span class="hlt">Earthquake</span> Machine</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>Hubenthal, Michael; Braile, Larry; Taber, John</p> <p>2008-01-01</p> <p>The <span class="hlt">Earthquake</span> Machine (EML), a mechanical <span class="hlt">model</span> of stick-slip fault systems, can increase student engagement and facilitate opportunities to participate in the scientific process. This article introduces the EML <span class="hlt">model</span> and an activity that challenges ninth-grade students' misconceptions about <span class="hlt">earthquakes</span>. The activity emphasizes the role of models…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Seismology&pg=7&id=EJ782558','ERIC'); return false;" href="http://eric.ed.gov/?q=Seismology&pg=7&id=EJ782558"><span>Redefining <span class="hlt">Earthquakes</span> and the <span class="hlt">Earthquake</span> Machine</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>Hubenthal, Michael; Braile, Larry; Taber, John</p> <p>2008-01-01</p> <p>The <span class="hlt">Earthquake</span> Machine (EML), a mechanical <span class="hlt">model</span> of stick-slip fault systems, can increase student engagement and facilitate opportunities to participate in the scientific process. This article introduces the EML <span class="hlt">model</span> and an activity that challenges ninth-grade students' misconceptions about <span class="hlt">earthquakes</span>. The activity emphasizes the role of models…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.T41F..01M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.T41F..01M"><span>The Decollement of the 2011 Great Tohoku <span class="hlt">Earthquake</span>: Oceanographic Provenance and a Potential <span class="hlt">Model</span> for Tsunami <span class="hlt">Earthquake</span> Production. (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moore, J. C.; Chester, F. M.; Plank, T. A.; Polissar, P. J.; Savage, H. M.</p> <p>2013-12-01</p> <p>At its deformation front, the Tohoku <span class="hlt">Earthquake</span>'s displacement was about 50 m. Slip was localized along a decollement consisting of pelagic brown clay. The brown clay of the Tohoku decollement at Site C0019 correlates lithologically with a lower portion of the pelagic brown clay section of Site 436, the 'reference' drill site closest to Site C0019 on the subducting Pacific Plate. The brown clay at Site 436 is of Eocene age, is dominated by smectite and illite, is extremely fine-grained, and unconformably overlies Cretaceous cherty mudstone. Similar pelagic clay layers occur at drill sites to the east and northeast of the Japan Trench. Pelagic clay may have been the slip surface of the 1896 Sanriku tsunami <span class="hlt">earthquake</span>, located just north of the Tohoku <span class="hlt">earthquake</span> along the Japan Trench. Both the Tohoku and Sanriku <span class="hlt">earthquakes</span> may have also been facilitated by the lack of large seamounts on the incoming Pacific Plate east of the Japan Trench. Moreover, the relatively thin sedimentary section overlying the pelagic clays in the Japan Trench may be offscraped and enable decollement development in the weak pelagic clay; this may not occur where a thick incoming terrigenous section offers options for decollement development at depth above the pelagic clays. Backtracking the plate motions of Sites 436 and C0019 shows that they initiate in the southern Pacific Ocean, accumulate concentrations of siliceous sediments crossing beneath the equatorial upwelling zone, enter the central north Pacific desert of pelagic clay deposition, and finally approach the margin of Japan where the upper section of Neogene, terrigenous-ashy-siliceous sediments dominate. Pelagic clay deposits are common in central, deep portions of the oceans that are shielded from terrigenous input. Thus, subduction of relatively smooth oceanic crust overlain by pelagic clay with a modest overburden of younger sediments may potentially foster a tsunami <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70028772','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70028772"><span>M ≥ 7.0 <span class="hlt">earthquake</span> recurrence on the San Andreas fault from a stress renewal <span class="hlt">model</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>Parsons, Thomas E.</p> <p>2006-01-01</p> <p> Forecasting M ≥ 7.0 San Andreas fault <span class="hlt">earthquakes</span> requires an assessment of their expected frequency. I used a three-dimensional finite element <span class="hlt">model</span> of California to calculate volumetric static stress drops from scenario M ≥ 7.0 <span class="hlt">earthquakes</span> 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 <span class="hlt">model</span> volume. Under a renewal <span class="hlt">model</span>, stress recovery times on ruptured fault planes can be a proxy for <span class="hlt">earthquake</span> 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 <span class="hlt">earthquake</span> frequencies, they fit Gutenberg-Richter relationships well matched to observed regional rates of M ≤ 6.0 <span class="hlt">earthquakes</span>. Thus a stress-balanced <span class="hlt">model</span> permits large <span class="hlt">earthquake</span> Gutenberg-Richter behavior on an individual fault segment, though it does not require it. <span class="hlt">Modeled</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFMED41B1171S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFMED41B1171S"><span>Undergraduate Research - Analyzing Data Sets: Global Positioning System (GPS) and <span class="hlt">Modeling</span> the 1994 Northridge <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>Simila, G.; Shubin, C.; Horn, W.</p> <p>2003-12-01</p> <p>Our undergraduate research program (2000-2003), funded by NASA, consisted of four short courses on the analysis of selected data sets from GPS, solar physics, orbital mechanics, and proteomics. During the program, approximately 80 students were recruited from science, math, engineering, and technology disciplines. This short course introduced students to GPS and <span class="hlt">earthquake</span> data analysis with additional presentations by scientists from JPL. Additional lectures involved discussions of the wave equation, Fourier analysis, statistical techniques, and computer applications of Excel and Matlab. Each student <span class="hlt">modeled</span> the observed GPS displacements produced by the 1994 Northridge <span class="hlt">earthquake</span> and presented an oral report. An additional component of the program involved students as research assistants engaged in a variety of projects at CSUN and JPL. Each short course continued the following semester with weekly research lectures.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.6891J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.6891J"><span>Were the May 2012 Emilia-Romagna <span class="hlt">earthquakes</span> induced? A coupled flow-geomechanics <span class="hlt">modeling</span> assessment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Juanes, R.; Jha, B.; Hager, B. H.; Shaw, J. H.; Plesch, A.; Astiz, L.; Dieterich, J. H.; Frohlich, C.</p> <p>2016-07-01</p> <p>Seismicity induced by fluid injection and withdrawal has emerged as a central element of the scientific discussion around subsurface technologies that tap into water and energy resources. Here we present the application of coupled flow-geomechanics simulation technology to the post mortem analysis of a sequence of damaging <span class="hlt">earthquakes</span> (Mw = 6.0 and 5.8) in May 2012 near the Cavone oil field, in northern Italy. This sequence raised the question of whether these <span class="hlt">earthquakes</span> might have been triggered by activities due to oil and gas production. Our analysis strongly suggests that the combined effects of fluid production and injection from the Cavone field were not a driver for the observed seismicity. More generally, our study illustrates that computational <span class="hlt">modeling</span> of coupled flow and geomechanics permits the integration of geologic, seismotectonic, well log, fluid pressure and flow rate, and geodetic data and provides a promising approach for assessing and managing hazards associated with induced seismicity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19880054601&hterms=California+history&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCalifornia%2Bhistory','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19880054601&hterms=California+history&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DCalifornia%2Bhistory"><span>A physical <span class="hlt">model</span> for <span class="hlt">earthquakes</span>. I - Fluctuations and interactions. II - Application to southern California</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rundle, John B.</p> <p>1988-01-01</p> <p>The idea that <span class="hlt">earthquakes</span> represent a fluctuation about the long-term motion of plates is expressed mathematically through the fluctuation hypothesis, under which all physical quantities which pertain to the occurance of <span class="hlt">earthquakes</span> are required to depend on the difference between the present state of slip on the fault and its long-term average. It is shown that under certain circumstances the <span class="hlt">model</span> fault dynamics undergo a sudden transition from a spatially ordered, temporally disordered state to a spatially disordered, temporally ordered state, and that the latter stages are stable for long intervals of time. For long enough faults, the dynamics are evidently chaotic. The methods developed are then used to construct a detailed <span class="hlt">model</span> for <span class="hlt">earthquake</span> dynamics in southern California. The result is a set of slip-time histories for all the major faults, which are similar to data obtained by geological trenching studies. Although there is an element of periodicity to the events, the patterns shift, change and evolve with time. Time scales for pattern evolution seem to be of the order of a thousand years for average recurring intervals of about a hundred years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790056259&hterms=forces+distance&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dforces%2Bdistance','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790056259&hterms=forces+distance&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dforces%2Bdistance"><span>Finite element <span class="hlt">modeling</span> of stress in the Nazca plate - Driving forces and plate boundary <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, R. M.</p> <p>1978-01-01</p> <p>The state of stress within the Nazca plate due to plate driving forces and large plate boundary <span class="hlt">earthquakes</span> has been analyzed by applying a finite element method using the wave front solution technique to <span class="hlt">models</span> of the intraplate stress field in a single plate using a refined grid. Although only static elastic <span class="hlt">models</span> have been explicitly calculated, certain limiting cases of an elastic plate over a viscous asthenosphere were also treated. A state of nearly east-west compression inferred from the source mechanism of thrust <span class="hlt">earthquakes</span> in the interior of the plate requires ridge pushing forces. The net pulling force on the oceanic plate by the subducted slab has a maximum value comparable to pushing forces. The estimated horizontal deviatoric stress in intraplate regions, based on potential forces associated with the ridge, is on the order of a few hundred bars. The intraplate stress field in the region of the 1960 <span class="hlt">earthquake</span> may change by a few tens of bars at most once the asthenosphere has relaxed, with changes on the order of one bar occurring at greater distances into the plate. The changes in the intraplate stress field are probably not noticeable unless the lithosphere is near failure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19790056259&hterms=driving+technique&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddriving%2Btechnique','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19790056259&hterms=driving+technique&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Ddriving%2Btechnique"><span>Finite element <span class="hlt">modeling</span> of stress in the Nazca plate - Driving forces and plate boundary <span class="hlt">earthquakes</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Richardson, R. M.</p> <p>1978-01-01</p> <p>The state of stress within the Nazca plate due to plate driving forces and large plate boundary <span class="hlt">earthquakes</span> has been analyzed by applying a finite element method using the wave front solution technique to <span class="hlt">models</span> of the intraplate stress field in a single plate using a refined grid. Although only static elastic <span class="hlt">models</span> have been explicitly calculated, certain limiting cases of an elastic plate over a viscous asthenosphere were also treated. A state of nearly east-west compression inferred from the source mechanism of thrust <span class="hlt">earthquakes</span> in the interior of the plate requires ridge pushing forces. The net pulling force on the oceanic plate by the subducted slab has a maximum value comparable to pushing forces. The estimated horizontal deviatoric stress in intraplate regions, based on potential forces associated with the ridge, is on the order of a few hundred bars. The intraplate stress field in the region of the 1960 <span class="hlt">earthquake</span> may change by a few tens of bars at most once the asthenosphere has relaxed, with changes on the order of one bar occurring at greater distances into the plate. The changes in the intraplate stress field are probably not noticeable unless the lithosphere is near failure.</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://www.ncbi.nlm.nih.gov/pubmed/14995508','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14995508"><span>Distribution of epicenters in the Olami-Feder-Christensen <span class="hlt">model</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Peixoto, Tiago P; Prado, Carmen P C</p> <p>2004-02-01</p> <p>We show that the well established Olami-Feder-Christensen (OFC) <span class="hlt">model</span> for the dynamics of <span class="hlt">earthquakes</span> is able to reproduce a striking property of real <span class="hlt">earthquake</span> data. Recently, it has been pointed out by Abe and Suzuki that the epicenters of <span class="hlt">earthquakes</span> could be connected in order to generate a graph, with properties of a scale-free network of the Barabási-Albert type. However, only the <span class="hlt">nonconservative</span> version of the Olami-Feder-Christensen <span class="hlt">model</span> is able to reproduce this behavior. The conservative version, instead, behaves like a random graph. Besides indicating the robustness of the <span class="hlt">model</span> to describe <span class="hlt">earthquake</span> dynamics, those findings reinforce that conservative and <span class="hlt">nonconservative</span> versions of the OFC <span class="hlt">model</span> are qualitatively different. Also, we propose a completely different dynamical mechanism that, even without an explicit rule of preferential attachment, generates a scale-free network. The preferential attachment is in this case a "byproduct" of the long term correlations associated with the self-organized critical state.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JAESc.100...20L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JAESc.100...20L"><span>Crustal rheology control on <span class="hlt">earthquake</span> activity across the eastern margin of the Tibetan Plateau: Insights from numerical <span class="hlt">modelling</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, Chang; Zhu, Bo-Jing; Yang, Xiao-Lin; Shi, Yao-Lin</p> <p>2015-03-01</p> <p>The devastating 2008 Mw7.9 Wenchuan and 2013 Mw6.6 Lushan <span class="hlt">earthquakes</span> occurred in the Longmen Shan (LMS) fault zone, the eastern margin of the Tibetan Plateau. Seismology investigation reveals that <span class="hlt">earthquakes</span> of Ms > 5.0 are frequently recorded in the eastern Tibetan Plateau, however rare <span class="hlt">earthquake</span> of Ms > 5.0 and only a few <span class="hlt">earthquakes</span> of 3.0 < Ms < 5.0 have been recorded in the Sichuan Basin. This study investigates the relation between the crustal rheology and the <span class="hlt">earthquake</span> activity across the eastern margin of the Tibetan Plateau through 3D numerical experiments assuming visco-elasticity rheology. We setup several finite element lithospheric <span class="hlt">models</span> based on different rheological structure. The interseismic stress accumulation processes in the <span class="hlt">models</span> are simulated with boundary conditions of steady compressional deformation rate constrained by GPS observations. The results show that the crustal stress accumulation process across the eastern margin of the Tibetan Plateau is significantly controlled by the regional crustal rheology, which presents large horizontal viscosity variation in the lower crusts between the Tibetan Plateau and the Sichuan Basin. The stress accumulation rate in the upper crust of the eastern Tibetan Plateau is much higher than the Sichuan Basin. This stress spatial distribution explains the seismology observation that <span class="hlt">earthquakes</span> are densely recorded in the eastern Tibetan Plateau, whereas rarely in the Sichuan Basin. The stress concentration nearly at the bottom of the entire LMS fault zone is thought to be responsible for the generation of the 2008 Mw7.9 Wenchuan and 2013 Mw6.6 Lushan <span class="hlt">earthquakes</span>. There is a high possibility of future <span class="hlt">earthquakes</span> in the seismic gaps at the southwest segment of the LMS fault zone, where it was stress accumulated but did not rupture during the last two events of the 2008 Wenchuan and 2013 Lushan <span class="hlt">earthquakes</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.7929B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.7929B"><span>Heterogeneous slip distribution on faults responsible for large <span class="hlt">earthquakes</span>: characterization and implications for tsunami <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Baglione, Enrico; Armigliato, Alberto; Pagnoni, Gianluca; Tinti, Stefano</p> <p>2017-04-01</p> <p>The fact that ruptures on the generating faults of large <span class="hlt">earthquakes</span> are strongly heterogeneous has been demonstrated over the last few decades by a large number of studies. The effort to retrieve reliable finite-fault <span class="hlt">models</span> (FFMs) for large <span class="hlt">earthquakes</span> occurred worldwide, mainly by means of the inversion of different kinds of geophysical data, has been accompanied in the last years by the systematic collection and format homogenisation of the published/proposed FFMs for different <span class="hlt">earthquakes</span> into specifically conceived databases, such as SRCMOD. The main aim of this study is to explore characteristic patterns of the slip distribution of large <span class="hlt">earthquakes</span>, by using a subset of the FFMs contained in SRCMOD, covering events with moment magnitude equal or larger than 6 and occurred worldwide over the last 25 years. We focus on those FFMs that exhibit a single and clear region of high slip (i.e. a single asperity), which is found to represent the majority of the events. For these FFMs, it sounds reasonable to best-fit the slip <span class="hlt">model</span> by means of a 2D Gaussian distributions. Two different methods are used (least-square and highest-similarity) and correspondingly two "best-fit" indexes are introduced. As a result, two distinct 2D Gaussian distributions for each FFM are obtained. To quantify how well these distributions are able to mimic the original slip heterogeneity, we calculate and compare the vertical displacements at the Earth surface in the near field induced by the original FFM slip, by an equivalent uniform-slip <span class="hlt">model</span>, by a depth-dependent slip <span class="hlt">model</span>, and by the two "best" Gaussian slip <span class="hlt">models</span>. The coseismic vertical surface displacement is used as the metric for comparison. Results show that, on average, the best results are the ones obtained with 2D Gaussian distributions based on similarity index fitting. Finally, we restrict our attention to those single-asperity FFMs associated to <span class="hlt">earthquakes</span> which generated tsunamis. We choose few events for which tsunami</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004AGUFM.S43C1010N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004AGUFM.S43C1010N"><span>Packaged Fault <span class="hlt">Model</span> for Geometric Segmentation of Active Faults Into <span class="hlt">Earthquake</span> Source Faults</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nakata, T.; Kumamoto, T.</p> <p>2004-12-01</p> <p>In Japan, the empirical formula proposed by Matsuda (1975) mainly based on the length of the historical surface fault ruptures and magnitude, is generally applied to estimate the size of future <span class="hlt">earthquakes</span> from the extent of existing active faults for seismic hazard assessment. Therefore validity of the active fault length and defining individual segment boundaries where propagating ruptures terminate are essential and crucial to the reliability for the accurate assessments. It is, however, not likely for us to clearly identify the behavioral <span class="hlt">earthquake</span> segments from observation of surface faulting during the historical period, because most of the active faults have longer recurrence intervals than 1000 years in Japan. Besides uncertainties of the datasets obtained mainly from fault trenching studies are quite large for fault grouping/segmentation. This is why new methods or criteria should be applied for active fault grouping/segmentation, and one of the candidates may be geometric criterion of active faults. Matsuda (1990) used _gfive kilometer_h as a critical distance for grouping and separation of neighboring active faults. On the other hand, Nakata and Goto (1998) proposed the geometric criteria such as (1) branching features of active fault traces and (2) characteristic pattern of vertical-slip distribution along the fault traces as tools to predict rupture length of future <span class="hlt">earthquakes</span>. The branching during the fault rupture propagation is regarded as an effective energy dissipation process and could result in final rupture termination. With respect to the characteristic pattern of vertical-slip distribution, especially with strike-slip components, the up-thrown sides along the faults are, in general, located on the fault blocks in the direction of relative strike-slip. Applying these new geometric criteria to the high-resolution active fault distribution maps, the fault grouping/segmentation could be more practically conducted. We tested this <span class="hlt">model</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70014159','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70014159"><span>Crustal velocities near Coalinga, California, <span class="hlt">modeled</span> from a combined <span class="hlt">earthquake</span>/explosion refraction profile</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Macgregor-Scott, N.; Walter, A.</p> <p>1988-01-01</p> <p>Crustal velocity structure for the region near Coalinga, California, has been derived from both <span class="hlt">earthquake</span> and explosion seismic phase data recorded along a NW-SE seismic-refraction profile on the western flank of the Great Valley east of the Diablo Range. Comparison of the two data sets reveals P-wave phases in common which can be correlated with changes in the velocity structure below the <span class="hlt">earthquake</span> hypocenters. In addition, the <span class="hlt">earthquake</span> records reveal secondary phases at station ranges of less than 20 km that could be the result of S- to P-wave conversions at velocity interfaces above the <span class="hlt">earthquake</span> hypocenters. Two-dimensional ray-trace <span class="hlt">modeling</span> of the P-wave travel times resulted in a P-wave velocity <span class="hlt">model</span> for the western flank of the Great Valley comprised of: 1) a 7- to 9-km thick section of sedimentary strata with velocities similar to those found elsewhere in the Great Valley (1.6 to 5.2 km s-1); 2) a middle crust extending to about 14 km depth with velocities comparable to those reported for the Franciscan assemblage in the Diablo Range (5.6 to 5.9 km s-1); and 3) a 13- to 14-km thick lower crust with velocities similar to those reported beneath the Diablo Range and the Great Valley (6.5 to 7.30 km s-1). This lower crust may have been derived from subducted oceanic crust that was thickened by accretionary underplating or crustal shortening. -Authors</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S21C..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S21C..08M"><span><span class="hlt">Modeling</span> Time Dependent <span class="hlt">Earthquake</span> Magnitude Distributions Associated with Injection-Induced Seismicity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maurer, J.; Segall, P.</p> <p>2015-12-01</p> <p>Understanding and predicting <span class="hlt">earthquake</span> magnitudes from injection-induced seismicity is critically important for estimating hazard due to injection operations. A particular problem has been that the largest event often occurs post shut-in. A rigorous analysis would require <span class="hlt">modeling</span> all stages of <span class="hlt">earthquake</span> nucleation, propagation, and arrest, and not just initiation. We present a simple conceptual <span class="hlt">model</span> for predicting the distribution of <span class="hlt">earthquake</span> magnitudes during and following injection, building on the analysis of Segall & Lu (2015). The analysis requires several assumptions: (1) the distribution of source dimensions follows a Gutenberg-Richter distribution; (2) in environments where the background ratio of shear to effective normal stress is low, the size of induced events is limited by the volume perturbed by injection (e.g., Shapiro et al., 2013; McGarr, 2014), and (3) the perturbed volume can be approximated by diffusion in a homogeneous medium. Evidence for the second assumption comes from numerical studies that indicate the background ratio of shear to normal stress controls how far an <span class="hlt">earthquake</span> rupture, once initiated, can grow (Dunham et al., 2011; Schmitt et al., submitted). We derive analytical expressions that give the rate of events of a given magnitude as the product of three terms: the time-dependent rate of nucleations, the probability of nucleating on a source of given size (from the Gutenberg-Richter distribution), and a time-dependent geometrical factor. We verify our results using simulations and demonstrate characteristics observed in real induced sequences, such as time-dependent b-values and the occurrence of the largest event post injection. We compare results to Segall & Lu (2015) as well as example datasets. Future work includes using 2D numerical simulations to test our results and assumptions; in particular, investigating how background shear stress and fault roughness control rupture extent.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S41D..06F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S41D..06F"><span>Assessing the quality of <span class="hlt">earthquake</span> source <span class="hlt">models</span> using 3-D forward <span class="hlt">modelling</span> of long-period seismic data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ferreira, A. M.; Vallée, M.; Lentas, K.</p> <p>2010-12-01</p> <p>Accurate <span class="hlt">earthquake</span> point source parameters (e.g. seismic moment, depth and focal mechanism) provide key first-order information for detailed studies of the <span class="hlt">earthquake</span> source process and for improved seismic and tsunami hazard evaluation. In order to objectively assess the quality of seismic source <span class="hlt">models</span>, it is important to go beyond classical resolution/misfit checks. In particular, it is desirable to apply sophisticated <span class="hlt">modeling</span> techniques to quantify uncertainties due to simplified theoretical formulations and/or Earth structure employed to build the source <span class="hlt">models</span>. Moreover, it is important to verify how well the <span class="hlt">models</span> explain data not used in their construction for a complete, quantitative assessment of the <span class="hlt">earthquake</span> source <span class="hlt">models</span>. In this study we compare the quality of the surface-wave Centroid Moment Tensor (CMT) method with that of the SCARDEC method, which is a new automated body-wave technique for the fast simultaneous determination of the seismic moment, focal mechanism, depth and source time functions of large <span class="hlt">earthquakes</span>. We focus on the major shallow subduction <span class="hlt">earthquakes</span> of the last 20 years, for which there are some systematic differences between SCARDEC and CMT source parameters, notably in fault dip angle and moment magnitude. Because the SCARDEC method is based on body-wave deconvolution using ray methods in a 1D Earth <span class="hlt">model</span>, we test how well SCARDEC source parameters explain long-period seismic data (surface waves and normal modes) compared to the CMT method. We calculate theoretical seismograms using two forward <span class="hlt">modelling</span> techniques (full ray theory and spectral element method) to simulate the long-period seismic wavefield for the 3D Earth <span class="hlt">model</span> S20RTS combined with the crust <span class="hlt">model</span> CRUST2.0, and for two point source <span class="hlt">models</span>: (i) the SCARDEC <span class="hlt">model</span>; and (ii) the Global CMT <span class="hlt">model</span>. We compare the synthetic seismograms with real broadband data from the FDSN for the major subduction <span class="hlt">earthquakes</span> of the last 20 years. We show that SCARDEC source</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013EGUGA..15.3974B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013EGUGA..15.3974B"><span>Comparing <span class="hlt">earthquake</span> <span class="hlt">models</span> for the Corinth rift for Mw>=5.5/6/6.5 (Greece)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Boiselet, Aurélien; Scotti, Oona; Lyon-Caen, Hélène; Ford, Mary; Meyer, NIcolas; Bernard, Pascal</p> <p>2013-04-01</p> <p>The Corinth rift (Greece) is identified as a site of major importance for <span class="hlt">earthquake</span> studies in Europe, producing one of the highest seismic activity and strain in the Euro-Mediterranean region. It is characterized by an asymmetrical structure, with the most active normal faults dipping north and a north-south extension rate measured by GPS increasing from 0.6 mm/year in the eastern part of the rift to 15 mm/year in the western part. Frequent seismic swarms and destructive <span class="hlt">earthquakes</span> are observed in this area. The Corinth rift Laboratory (CRL, http://crlab.eu) european project investigates fault mechanics, its relationship with <span class="hlt">earthquakes</span>, fluid flow and the related hazards in the western part of the rift, covering an area about 50 km by 40 km, between the city of Patras to the west and the city of Aigion to the east. As part of this project, within the CRL-SISCOR group, we construct <span class="hlt">earthquake</span> forecast <span class="hlt">models</span> (EFM) for M>=5.5/6/6.5 events of the Corinth rift area based on the in-depth seismotectonic studies available for this region. We first present the methodology used to construct the <span class="hlt">earthquake</span> and fault databases and to quantify the associated uncertainties. We then propose EFM following two approaches: one based on the definition of seimotectonic areas with similar geologic or strain characteristics, the second one based on the definition of fault sources mapped at the surface as well as blind ones. In order to compute the probability of occurrence for M>=5.5/6/6.5 for seismotectonic areas, we analyse two <span class="hlt">earthquake</span> catalogues available for Greece (National Observatory of Athens, Thessaloniki), apply two declustering methods (Reasenberg and Gardner) to construct a Poissonian <span class="hlt">earthquake</span> catalogue and test the influence of the minimal magnitude (3.5; 4.0). We compare the impact of maximum magnitude and corner magnitude (Kagan 1997, 2002) estimations. We then apply the Weichert method to estimate the probability of occurrence of M>=5.5/6/6.5 based on</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AcGeo.tmp...65F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AcGeo.tmp...65F"><span><span class="hlt">Earthquake</span> hazard assessment in the Zagros Orogenic Belt of Iran using a fuzzy rule-based <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Farahi Ghasre Aboonasr, Sedigheh; Zamani, Ahmad; Razavipour, Fatemeh; Boostani, Reza</p> <p>2017-06-01</p> <p>Producing accurate seismic hazard map and predicting hazardous areas is necessary for risk mitigation strategies. In this paper, a fuzzy logic inference system is utilized to estimate the <span class="hlt">earthquake</span> potential and seismic zoning of Zagros Orogenic Belt. In addition to the interpretability, fuzzy predictors can capture both nonlinearity and chaotic behavior of data, where the number of data is limited. In this paper, <span class="hlt">earthquake</span> pattern in the Zagros has been assessed for the intervals of 10 and 50 years using fuzzy rule-based <span class="hlt">model</span>. The Molchan statistical procedure has been used to show that our forecasting <span class="hlt">model</span> is reliable. The <span class="hlt">earthquake</span> hazard maps for this area reveal some remarkable features that cannot be observed on the conventional maps. Regarding our achievements, some areas in the southern (Bandar Abbas), southwestern (Bandar Kangan) and western (Kermanshah) parts of Iran display high <span class="hlt">earthquake</span> severity even though they are geographically far apart.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRB..121.8113L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRB..121.8113L"><span>Assessment of <span class="hlt">earthquake</span> locations in 3-D deterministic velocity <span class="hlt">models</span>: A case study from the Altotiberina Near Fault Observatory (Italy)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Latorre, D.; Mirabella, F.; Chiaraluce, L.; Trippetta, F.; Lomax, A.</p> <p>2016-11-01</p> <p>The accuracy of <span class="hlt">earthquake</span> locations and their correspondence with subsurface geology depends strongly on the accuracy of the available seismic velocity <span class="hlt">model</span>. Most modern methods to construct a velocity <span class="hlt">model</span> for <span class="hlt">earthquake</span> location are based on the inversion of passive source seismological data. Another approach is the integration of high-resolution geological and geophysical data to construct deterministic velocity <span class="hlt">models</span> in which <span class="hlt">earthquake</span> locations can be directly correlated to the geological structures. Such <span class="hlt">models</span> have to be kinematically consistent with independent seismological data in order to provide precise hypocenter solutions. We present the Altotiberina (AT) seismic <span class="hlt">model</span>, a three-dimensional velocity <span class="hlt">model</span> for the Upper Tiber Valley region (Northern Apennines, Italy), constructed by combining 300 km of seismic reflection profiles, six deep boreholes (down to 5 km depth), detailed data from geological surveys and direct measurements of P and S wave velocities performed in situ and in laboratory. We assess the robustness of the AT seismic <span class="hlt">model</span> by locating 11,713 <span class="hlt">earthquakes</span> with a nonlinear, global-search inversion method and comparing the probabilistic hypocenter solutions to those calculated in three previously published velocity <span class="hlt">models</span>, constructed by inverting passive seismological data only. Our results demonstrate that the AT seismic <span class="hlt">model</span> is able to provide higher-quality hypocenter locations than the previous velocity <span class="hlt">models</span>. <span class="hlt">Earthquake</span> locations are consistent with the subsurface geological structures and show a high degree of spatial correlation with specific lithostratigraphic units, suggesting a lithological control on the seismic activity evolution.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24483388','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24483388"><span>Stability of <span class="hlt">earthquake</span> clustering <span class="hlt">models</span>: criticality and branching ratios.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhuang, Jiancang; Werner, Maximilian J; Harte, David S</p> <p>2013-12-01</p> <p>We study the stability conditions of a class of branching processes prominent in the analysis and <span class="hlt">modeling</span> of seismicity. This class includes the epidemic-type aftershock sequence (ETAS) <span class="hlt">model</span> as a special case, but more generally comprises <span class="hlt">models</span> in which the magnitude distribution of direct offspring depends on the magnitude of the progenitor, such as the branching aftershock sequence (BASS) <span class="hlt">model</span> and another recently proposed branching <span class="hlt">model</span> based on a dynamic scaling hypothesis. These stability conditions are closely related to the concepts of the criticality parameter and the branching ratio. The criticality parameter summarizes the asymptotic behavior of the population after sufficiently many generations, determined by the maximum eigenvalue of the transition equations. The branching ratio is defined by the proportion of triggered events in all the events. Based on the results for the generalized case, we show that the branching ratio of the ETAS <span class="hlt">model</span> is identical to its criticality parameter because its magnitude density is separable from the full intensity. More generally, however, these two values differ and thus place separate conditions on <span class="hlt">model</span> stability. As an illustration of the difference and of the importance of the stability conditions, we employ a version of the BASS <span class="hlt">model</span>, reformulated to ensure the possibility of stationarity. In addition, we analyze the magnitude distributions of successive generations of the BASS <span class="hlt">model</span> via analytical and numerical methods, and find that the compound density differs substantially from a Gutenberg-Richter distribution, unless the process is essentially subcritical (branching ratio less than 1) or the magnitude dependence between the parent event and the direct offspring is weak.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhRvE..88f2109Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhRvE..88f2109Z"><span>Stability of <span class="hlt">earthquake</span> clustering <span class="hlt">models</span>: Criticality and branching ratios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhuang, Jiancang; Werner, Maximilian J.; Harte, David S.</p> <p>2013-12-01</p> <p>We study the stability conditions of a class of branching processes prominent in the analysis and <span class="hlt">modeling</span> of seismicity. This class includes the epidemic-type aftershock sequence (ETAS) <span class="hlt">model</span> as a special case, but more generally comprises <span class="hlt">models</span> in which the magnitude distribution of direct offspring depends on the magnitude of the progenitor, such as the branching aftershock sequence (BASS) <span class="hlt">model</span> and another recently proposed branching <span class="hlt">model</span> based on a dynamic scaling hypothesis. These stability conditions are closely related to the concepts of the criticality parameter and the branching ratio. The criticality parameter summarizes the asymptotic behavior of the population after sufficiently many generations, determined by the maximum eigenvalue of the transition equations. The branching ratio is defined by the proportion of triggered events in all the events. Based on the results for the generalized case, we show that the branching ratio of the ETAS <span class="hlt">model</span> is identical to its criticality parameter because its magnitude density is separable from the full intensity. More generally, however, these two values differ and thus place separate conditions on <span class="hlt">model</span> stability. As an illustration of the difference and of the importance of the stability conditions, we employ a version of the BASS <span class="hlt">model</span>, reformulated to ensure the possibility of stationarity. In addition, we analyze the magnitude distributions of successive generations of the BASS <span class="hlt">model</span> via analytical and numerical methods, and find that the compound density differs substantially from a Gutenberg-Richter distribution, unless the process is essentially subcritical (branching ratio less than 1) or the magnitude dependence between the parent event and the direct offspring is weak.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/232644','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/232644"><span>Helicity <span class="hlt">non-conserving</span> form factor of the proton</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Voutier, E.; Furget, C.; Knox, S.</p> <p>1994-04-01</p> <p>The study of the hadron structure in the high Q{sup 2} range contributes to the understanding of the mechanisms responsible for the confinement of quarks and gluons. Among the numerous experimental candidates sensitive to these mechanisms, the helicity <span class="hlt">non-conserving</span> form factor of the proton is a privileged observable since it is controlled by non-perturbative effects. The authors investigate here the feasibility of high Q{sup 2} measurements of this form factor by means of the recoil polarization method in the context of the CEBAF 8 GeV facility. For that purpose, they discuss the development of a high energy proton polarimeter, based on the H({rvec p},pp) elastic scattering, to be placed at the focal plane of a new hadron spectrometer. It is shown that this experimental method significantly improves the knowledge of the helicity <span class="hlt">non-conserving</span> form factor of the proton up to 10 GeV{sup 2}/c{sup 2}.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003AGUFM.S42C0188M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003AGUFM.S42C0188M"><span>The Energy Budget of <span class="hlt">Earthquake</span> Rupture: a View From Spontaneous Rupture <span class="hlt">Modeling</span> and Finite-Source <span class="hlt">Models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mai, P.; Guatteri, M.</p> <p>2003-12-01</p> <p>It is a common and frustrating experience of many dynamic <span class="hlt">modelers</span> to initiate spontaneous rupture calculations that subsequently abort before rupturing to the desired <span class="hlt">earthquake</span> size [Nielsen and Olsen, 2000; Oglesby and Day, 2002]. Source parameters in such dynamic source <span class="hlt">models</span> are strongly correlated, but stress drop is the main factor affecting the distribution of the other dynamic rupture parameters. Additionally, the position of the hypocenter exerts a strong influence on the dynamic properties of the <span class="hlt">earthquake</span>, and certain hypocenter positions are not plausible as those would not lead to spontaneous rupture propagation. To further investigate this last statement, we analyze the energy budget during <span class="hlt">earthquake</span> rupture using spontaneous dynamic rupture calculations and finite-source rupture <span class="hlt">models</span>. In describing the energy budget during <span class="hlt">earthquake</span> rupture, we follow Favreau and Archuleta [2003]. Each point on the fault contributes to the radiated seismic energy Ers = Eel - Efr - Erx, where Eel denotes the elasto-static energy and Efr the fracture energy. In this study we neglect for simplicity the relaxation work Erx spent during the stopping of the <span class="hlt">earthquake</span>. A rupture can be characterized by locally negative seismic energy density values, but its integral over the fault plane must be positive. The fundamental condition for rupture growth is therefore that the integral of Ers on the rupture area remains always positive during rupture propagation. Based on a simple energy budget calculation, we focus on identifying those target slip/stress distribution in dynamic rupture <span class="hlt">modeling</span> that for a given hypocenter location fail to rupture spontaneously. Additionally, we study the energy budget of finite-source rupture <span class="hlt">models</span> by analyzing the integrated seismic energy for the inferred slip maps using also hypocenter positions other than the network location. These results indicate how rupture was promoted for the true hypocenter while randomized hypocenters may not</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70032137','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70032137"><span>Ground-motion <span class="hlt">modeling</span> of the 1906 San Francisco <span class="hlt">Earthquake</span>, part II: Ground-motion estimates for the 1906 <span class="hlt">earthquake</span> and scenario events</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Aagaard, B.T.; Brocher, T.M.; Dolenc, D.; Dreger, D.; Graves, R.W.; Harmsen, S.; Hartzell, S.; Larsen, S.; McCandless, K.; Nilsson, S.; Petersson, N.A.; Rodgers, A.; Sjogreen, B.; Zoback, M.L.</p> <p>2008-01-01</p> <p>We estimate the ground motions produce by the 1906 San Francisco <span class="hlt">earthquake</span> making use of the recently developed Song et al. (2008) source <span class="hlt">model</span> that combines the available geodetic and seismic observations and recently constructed 3D geologic and seismic velocity <span class="hlt">models</span>. Our estimates of the ground motions for the 1906 <span class="hlt">earthquake</span> are consistent across five ground-motion <span class="hlt">modeling</span> groups employing different wave propagation codes and simulation domains. The simulations successfully reproduce the main features of the Boatwright and Bundock (2005) ShakeMap, but tend to over predict the intensity of shaking by 0.1-0.5 modified Mercalli intensity (MMI) units. Velocity waveforms at sites throughout the San Francisco Bay Area exhibit characteristics consistent with rupture directivity, local geologic conditions (e.g., sedimentary basins), and the large size of the event (e.g., durations of strong shaking lasting tens of seconds). We also compute ground motions for seven hypothetical scenarios rupturing the same extent of the northern San Andreas fault, considering three additional hypocenters and an additional, random distribution of slip. Rupture directivity exerts the strongest influence on the variations in shaking, although sedimentary basins do consistently contribute to the response in some locations, such as Santa Rosa, Livermore, and San Jose. These scenarios suggest that future large <span class="hlt">earthquakes</span> on the northern San Andreas fault may subject the current San Francisco Bay urban area to stronger shaking than a repeat of the 1906 <span class="hlt">earthquake</span>. Ruptures propagating southward towards San Francisco appear to expose more of the urban area to a given intensity level than do ruptures propagating northward.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFM.S12B1194A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFM.S12B1194A"><span>3-D Finite-Difference <span class="hlt">Modeling</span> of <span class="hlt">Earthquakes</span> in the City of Rome, Italy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Akinci, A.; Olsen, K. B.; Rovelli, A.; Marra, F.; Malagnini, L.</p> <p>2002-12-01</p> <p>The goal of this study is to estimate 3-D amplification effects from regional and local <span class="hlt">earthquakes</span> in the city of Rome. Mainly, two distinct seismogenic districts may affect the city of Rome: the (1) Alban Hills region, located about 25 km from downtown Rome, and (2) the Central Apennines, located 80-100 km from Rome where the most recent event occurred on January 13, 1915 (M=6.8) which was felt in Rome with a VII degree intensity. To address the seismic hazard in Rome from such sources we have simulated 0-1 Hz viscoelastic wave propagation in a three-dimensional <span class="hlt">model</span> of the Tiber Valley, Rome, for an M5.5 scenario <span class="hlt">earthquake</span> (1 Hz) in the seismogenic area of Alban Hills about 25 km from downtown Rome and an M7.0 <span class="hlt">earthquake</span> (0.5 Hz) about 100 km east of the valley using a fourth-order staggered-grid finite-difference method. We used a basin <span class="hlt">model</span> (~ 6 km by 6 km by 0.050 km) which includes sediments with shear-wave velocities as low as 250 m/s in the Tiber River sediments, constrained by more than 3000 borehole measurements. We have also estimated the amplification of the 3D <span class="hlt">model</span> due to a 1-Hz vertically-incident planar SH wave. Our results suggest that the strongest ground motion amplification in Rome is restricted to the Holocene alluvial areas with a significant concentration close to the edges of the Tiber River valley, in agreement with the results by Tertulliani and Riguzzi (1995). In particular, the fill deposits in the Tiber River generate amplification by up to a factor of 2 with respect to the surrounding volcanics, largest near the contact between the alluvial sediments and the surrounding volcanic deposits for the incident plane wave source. We find 1-Hz peak ground velocities of up to 30 cm/sec for the M5.5, Alban Hills <span class="hlt">earthquake</span>, largest near the northwestern edges of the Tiber River. The largest 0.5-Hz peak velocity is 24 cm/s for the M7.0 <span class="hlt">earthquake</span> with extended durations up to about 1 min. The lower maximum frequency for this scenario is</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PApGe.171.1311C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PApGe.171.1311C"><span>6.9 Sikkim <span class="hlt">Earthquake</span> and <span class="hlt">Modeling</span> of Ground Motions to Determine Causative Fault</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chopra, Sumer; Sharma, Jyoti; Sutar, Anup; Bansal, B. K.</p> <p>2014-07-01</p> <p>In this study, source parameters of the September 18, 2011 M w 6.9, Sikkim <span class="hlt">earthquake</span> were determined using acceleration records. These parameters were then used to generate strong motion at a number of sites using the stochastic finite fault <span class="hlt">modeling</span> technique to constrain the causative fault plane for this <span class="hlt">earthquake</span>. The average values of corner frequency, seismic moment, stress drop and source radius were 0.12 Hz, 3.07 × 1026 dyne-cm, 115 bars and 9.68 km, respectively. The fault plane solution showed strike-slip movement with two nodal planes oriented along two prominent lineaments in the region, the NE-oriented Kanchendzonga and NW-oriented Tista lineaments. The ground motions were estimated considering both the nodal planes as causative faults and the results in terms of the peak ground accelerations (PGA) and Fourier spectra were then compared with the actual recordings. We found that the NW-SE striking nodal plane along the Tista lineament may have been the causative fault for the Sikkim <span class="hlt">earthquake</span>, as PGA estimates are comparable with the observed recordings. We also observed that the Fourier spectrum is not a good parameter in deciding the causative fault plane.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013PhyA..392.2868V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013PhyA..392.2868V"><span>Hidden Markov <span class="hlt">models</span> revealing the stress field underlying the <span class="hlt">earthquake</span> generation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Votsi, I.; Limnios, N.; Tsaklidis, G.; Papadimitriou, E.</p> <p>2013-07-01</p> <p>The application of the hidden Markov <span class="hlt">models</span> (HMMs) is attempted for revealing key features for the <span class="hlt">earthquake</span> generation which are not accessible to direct observation. Considering that the states of the HMM correspond to levels of the stress field, our objective is to identify these states. The observations are considered after grouping <span class="hlt">earthquake</span> magnitudes and the cases of different number of states are examined. The problems of HMMs theory are solved and the ensuing HMMs are compared on the basis of Akaike and Bayesian information criteria. A new insight on the evaluation of future seismic hazard is given by calculating the mean number of steps for the first visit to a particular state, along with the respective variance. We further calculate an estimator of the mean number of steps for the first visit to a particular state and we construct its confidence interval. Additionally, a second approach to the problem is followed by assuming a different determination of observations. The HMMs applied to both approaches, contribute significantly to seismic hazard assessment via revealing the number of the stress levels as well as the way in which these levels are associated with certain <span class="hlt">earthquake</span> occurrence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JSCSE..68..I20S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JSCSE..68..I20S"><span>FINITE FAULT <span class="hlt">MODELING</span> OF FUTURE LARGE <span class="hlt">EARTHQUAKE</span> FROM NORTH TEHRAN FAULT IN KARAJ, IRAN</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Samaei, Meghdad; Miyajima, Masakatsu; Saffari, Hamid; Tsurugi, Masato</p> <p></p> <p>The main purpose of this study is to predict strong ground motions from future large <span class="hlt">earthquake</span> for Karaj city, the capital of Alborz province of Iran. This city is an industrialized city having over one million populations and is located near several active faults. Finite fault <span class="hlt">modeling</span> with a dynamic corner frequency has adopted here for simulation of future large <span class="hlt">earthquake</span>. Target fault is North Tehran fault with the length of 110 km and rupture of west part of the fault which is closest to Karaj, assumed for this simulation. For seven rupture starting points, acceleration time series in the site of Karaj Caravansary -historical building- are predicted. Peak ground accelerations for those are vary from 423 cm/s2 to 584 cm/s2 which is in the range of 1990 Rudbar <span class="hlt">earthquake</span> (Mw=7.3) . Results of acceleration simulations in different distances are also compared with attenuation relations for two types of soil. Our simulations show general agreement with one of the most well known world attenuation relations and also with one of the newest attenuation relation that hase developed for Iranian plateau.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70044047','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70044047"><span>Spatial aspects of building and population exposure data and their implications for global <span class="hlt">earthquake</span> exposure <span class="hlt">modeling</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>Dell’Acqua, F.; Gamba, P.; Jaiswal, K.</p> <p>2012-01-01</p> <p>This paper discusses spatial aspects of the global exposure dataset and mapping needs for <span class="hlt">earthquake</span> risk assessment. We discuss this in the context of development of a Global Exposure Database for the Global <span class="hlt">Earthquake</span> <span class="hlt">Model</span> (GED4GEM), which requires compilation of a multi-scale inventory of assets at risk, for example, buildings, populations, and economic exposure. After defining the relevant spatial and geographic scales of interest, different procedures are proposed to disaggregate coarse-resolution data, to map them, and if necessary to infer missing data by using proxies. We discuss the advantages and limitations of these methodologies and detail the potentials of utilizing remote-sensing data. The latter is used especially to homogenize an existing coarser dataset and, where possible, replace it with detailed information extracted from remote sensing using the built-up indicators for different environments. Present research shows that the spatial aspects of <span class="hlt">earthquake</span> risk computation are tightly connected with the availability of datasets of the resolution necessary for producing sufficiently detailed exposure. The global exposure database designed by the GED4GEM project is able to manage datasets and queries of multiple spatial scales.</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://pubs.er.usgs.gov/publication/70045077','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70045077"><span>Relation of landslides triggered by the Kiholo Bay <span class="hlt">earthquake</span> to <span class="hlt">modeled</span> ground motion</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Harp, Edwin L.; Hartzell, Stephen H.; Jibson, Randall W.; Ramirez-Guzman, L.; Schmitt, Robert G.</p> <p>2014-01-01</p> <p>The 2006 Kiholo Bay, Hawaii, <span class="hlt">earthquake</span> triggered high concentrations of rock falls and slides in the steep canyons of the Kohala Mountains along the north coast of Hawaii. Within these mountains and canyons a complex distribution of landslides was triggered by the <span class="hlt">earthquake</span> shaking. In parts of the area, landslides were preferentially located on east‐facing slopes, whereas in other parts of the canyons no systematic pattern prevailed with respect to slope aspect or vertical position on the slopes. The geology within the canyons is homogeneous, so we hypothesize that the variable landslide distribution is the result of localized variation in ground shaking; therefore, we used a state‐of‐the‐art, high‐resolution ground‐motion simulation <span class="hlt">model</span> to see if it could reproduce the landslide‐distribution patterns. We used a 3D finite‐element analysis to <span class="hlt">model</span> <span class="hlt">earthquake</span> shaking using a 10 m digital elevation <span class="hlt">model</span> and slip on a finite‐fault <span class="hlt">model</span> constructed from teleseismic records of the mainshock. Ground velocity time histories were calculated up to a frequency of 5 Hz. Dynamic shear strain also was calculated and compared with the landslide distribution. Results were mixed for the velocity simulations, with some areas showing correlation of landslide locations with peak <span class="hlt">modeled</span> ground motions but many other areas showing no such correlation. Results were much improved for the comparison with dynamic shear strain. This suggests that (1) rock falls and slides are possibly triggered by higher frequency ground motions (velocities) than those in our simulations, (2) the ground‐motion velocity <span class="hlt">model</span> needs more refinement, or (3) dynamic shear strain may be a more fundamental measurement of the decoupling process of slope materials during seismic shaking.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4784842','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4784842"><span>An Integrated and Interdisciplinary <span class="hlt">Model</span> for Predicting the Risk of Injury and Death in Future <span class="hlt">Earthquakes</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>Shapira, Stav; Novack, Lena; Bar-Dayan, Yaron; Aharonson-Daniel, Limor</p> <p>2016-01-01</p> <p>Background A comprehensive technique for <span class="hlt">earthquake</span>-related casualty estimation remains an unmet challenge. This study aims to integrate risk factors related to characteristics of the exposed population and to the built environment in order to improve communities’ preparedness and response capabilities and to mitigate future consequences. Methods An innovative <span class="hlt">model</span> was formulated based on a widely used loss estimation <span class="hlt">model</span> (HAZUS) by integrating four human-related risk factors (age, gender, physical disability and socioeconomic status) that were identified through a systematic review and meta-analysis of epidemiological data. The common effect measures of these factors were calculated and entered to the existing model’s algorithm using logistic regression equations. Sensitivity analysis was performed by conducting a casualty estimation simulation in a high-vulnerability risk area in Israel. Results the integrated <span class="hlt">model</span> outcomes indicated an increase in the total number of casualties compared with the prediction of the traditional <span class="hlt">model</span>; with regard to specific injury levels an increase was demonstrated in the number of expected fatalities and in the severely and moderately injured, and a decrease was noted in the lightly injured. Urban areas with higher populations at risk rates were found more vulnerable in this regard. Conclusion The proposed <span class="hlt">model</span> offers a novel approach that allows quantification of the combined impact of human-related and structural factors on the results of <span class="hlt">earthquake</span> casualty <span class="hlt">modelling</span>. Investing efforts in reducing human vulnerability and increasing resilience prior to an occurrence of an <span class="hlt">earthquake</span> could lead to a possible decrease in the expected number of casualties. PMID:26959647</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017AdSpR..60.1787C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017AdSpR..60.1787C"><span>Numerical <span class="hlt">modeling</span> of possible lower ionospheric anomalies associated with Nepal <span class="hlt">earthquake</span> in May, 2015</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chakraborty, Suman; Sasmal, Sudipta; Basak, Tamal; Ghosh, Soujan; Palit, Sourav; Chakrabarti, Sandip K.; Ray, Suman</p> <p>2017-10-01</p> <p>We present perturbations due to seismo-ionospheric coupling processes in propagation characteristics of sub-ionospheric Very Low Frequency (VLF) signals received at Ionospheric & <span class="hlt">Earthquake</span> Research Centre (IERC) (Lat. 22.50°N, Long. 87.48°E), India. The study is done during and prior to an <span class="hlt">earthquake</span> of Richter scale magnitude M = 7.3 occurring at a depth of 18 km at southeast of Kodari, Nepal on 12 May 2015 at 12:35:19 IST (07:05:19 UT). The recorded VLF signal of Japanese transmitter JJI at frequency 22.2 kHz (Lat. 32.08°N, Long. 130.83°E) suffers from strong shifts in sunrise and sunset terminator times towards nighttime starting from three to four days prior to the <span class="hlt">earthquake</span>. The signal shows a similar variation in terminator times during a major aftershock of magnitude M = 6.7 on 16 May, 2015 at 17:04:10 IST (11:34:10 UT). These shifts in terminator times is numerically <span class="hlt">modeled</span> using Long Wavelength Propagation Capability (LWPC) Programme. The unperturbed VLF signal is simulated by using the day and night variation of reflection height (h‧) and steepness parameter (β) fed in LWPC for the entire path. The perturbed signal is obtained by additional variation of these parameters inside the <span class="hlt">earthquake</span> preparation zone. It is found that the shift of the terminator time towards nighttime happens only when the reflection height is increased. We also calculate electron density profile by using the Wait's exponential formula for specified location over the propagation path.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120010090&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DEarthquake','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120010090&hterms=Earthquake&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DEarthquake"><span>Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) <span class="hlt">Model</span> - An Unified Concept for <span class="hlt">Earthquake</span> Precursors Validation</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Pulinets, S.; Ouzounov, D.</p> <p>2010-01-01</p> <p>The paper presents a conception of complex multidisciplinary approach to the problem of clarification the nature of short-term <span class="hlt">earthquake</span> precursors observed in atmosphere, atmospheric electricity and in ionosphere and magnetosphere. Our approach is based on the most fundamental principles of tectonics giving understanding that <span class="hlt">earthquake</span> is an ultimate result of relative movement of tectonic plates and blocks of different sizes. Different kind of gases: methane, helium, hydrogen, and carbon dioxide leaking from the crust can serve as carrier gases for radon including underwater seismically active faults. Radon action on atmospheric gases is similar to the cosmic rays effects in upper layers of atmosphere: it is the air ionization and formation by ions the nucleus of water condensation. Condensation of water vapor is accompanied by the latent heat exhalation is the main cause for observing atmospheric thermal anomalies. Formation of large ion clusters changes the conductivity of boundary layer of atmosphere and parameters of the global electric circuit over the active tectonic faults. Variations of atmospheric electricity are the main source of ionospheric anomalies over seismically active areas. Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) <span class="hlt">model</span> can explain most of these events as a synergy between different ground surface, atmosphere and ionosphere processes and anomalous variations which are usually named as short-term <span class="hlt">earthquake</span> precursors. A newly developed approach of Interdisciplinary Space-Terrestrial Framework (ISTF) can provide also a verification of these precursory processes in seismically active regions. The main outcome of this paper is the unified concept for systematic validation of different types of <span class="hlt">earthquake</span> precursors united by physical basis in one common theory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EaSci.tmp....9N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EaSci.tmp....9N"><span>Electrical triggering of <span class="hlt">earthquakes</span>: results of laboratory experiments at spring-block <span class="hlt">models</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Novikov, Victor A.; Okunev, Vladimir I.; Klyuchkin, Vadim N.; Liu, Jing; Ruzhin, Yuri Ya.; Shen, Xuhui</p> <p>2017-05-01</p> <p>Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current (DC) pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical <span class="hlt">earthquake</span> triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density (10-7-10-8 A/m2) generated by the pulsed power systems at the epicenter depth (5-10 km) of local <span class="hlt">earthquakes</span> occurred just after the current injection. The paper describes results of laboratory "<span class="hlt">earthquake</span>" triggering by DC pulses under conditions of a spring-block <span class="hlt">model</span> simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory "<span class="hlt">earthquake</span>" (sharp slip of a movable block of the spring-block system) is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site (Northern Tien Shan, Kirghizia) where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1730d0006M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1730d0006M"><span>Analysis of 2012 M8.6 Indian Ocean <span class="hlt">earthquake</span> coseismic slip <span class="hlt">model</span> based on GPS data</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maulida, Putra; Meilano, Irwan; Gunawan, Endra; Efendi, Joni</p> <p>2016-05-01</p> <p>The CGPS (Continuous Global Position System) data of Sumatran GPS Array (CGPS) and Indonesian Geospatial Agency (BIG) in Sumatra are processed to estimate the best fit coseismic <span class="hlt">model</span> of 2012 M8.6 Indian Ocean <span class="hlt">earthquake</span>. For GPS data processing, we used the GPS Analysis at Massachusetts Institute of Technology (GAMIT) 10.5 software and Global Kalman Filter (GLOBK) to generate position time series of each GPS stations and estimate the coseismic offset due to the <span class="hlt">Earthquake</span>. The result from GPS processing indicates that the <span class="hlt">earthquake</span> caused displacement northeast ward up to 25 cm in northern Sumatra. Results also show subsidence at the northern Sumatran while the central part of Sumatra show northwest direction displacement, but we cannot find whether the subsidence or the uplift signal associated to the <span class="hlt">earthquake</span> due to the vertical data quality. Based on the GPS coseismic data, we evaluate the coseismic slip <span class="hlt">model</span> of Indian Ocean <span class="hlt">Earthquake</span> produced by previous study [1], [2], [3]. We calculated coseismic displacement using half-space with <span class="hlt">earthquake</span> slip <span class="hlt">model</span> input and compare it with the displacement produced form GPS data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21821639','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21821639"><span>A rodent <span class="hlt">model</span> to advance the field treatment of crush muscle injury during <span class="hlt">earthquakes</span> and other natural disasters.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Speck, Kirsten; Schneider, Barbara St Pierre; Deashinta, Nadia</p> <p>2013-01-01</p> <p>Approximately 170 <span class="hlt">earthquakes</span> of 6.0 or higher magnitude occur annually worldwide. Victims often suffer crush muscle injuries involving impaired blood flow to the affected muscle and damage to the muscle fiber membrane. Current rescue efforts are directed toward preventing acute kidney injury (AKI), which develops upon extrication and muscle reperfusion. But field-usable, muscle-specific interventions may promote muscle regeneration and prevent or minimize the pathologic changes of reperfusion. Although current rodent crush injury <span class="hlt">models</span> involve reperfusion upon removal of the crush stimulus, an analysis of their methodological aspects is needed to ensure adequate simulation of the <span class="hlt">earthquake</span>-related crush injury. The objectives of this systematic review are to (a) describe rodent crush muscle injury <span class="hlt">models</span>, (b) discuss the benefits and limitations of these <span class="hlt">models</span>, and (c) offer a recommendation for animal <span class="hlt">models</span> that would increase our understanding of muscle recovery processes after an <span class="hlt">earthquake</span>-induced crush muscle injury. The most commonly used rodent <span class="hlt">model</span> uses a clamping or pressing crush stimulus directly applied to murine hindlimb muscle. This <span class="hlt">model</span> has increased our understanding of muscle regeneration but its open approach does not adequately represent the <span class="hlt">earthquake</span>-related crush injury. The <span class="hlt">model</span> we recommend for developing field-usable, muscle-specific interventions is a closed approach that involves a nonclamping crush stimulus. Findings from studies employing this recommended <span class="hlt">model</span> may have greater relevance for developing interventions that lessen the <span class="hlt">earthquake</span>'s devastating impact on individual and community health and quality of life, especially in developing countries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981PhLB..103..343M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981PhLB..103..343M"><span>Baryon <span class="hlt">nonconservation</span> at intermediate mass scales and matter-Antimatter asymmetry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Masiero, A.; Mohapatra, R. N.</p> <p>1981-07-01</p> <p>We discuss a mechanism for the generation of cosmological baryon asymmetry in a class of unification <span class="hlt">models</span> where baryon <span class="hlt">non-conservation</span> arises at mass scales much below the usual grand unification scale of 1015 GeV and obeys the ΔB = 2 selection rule. Application of this scenario to a previously discussed left-right symmetric <span class="hlt">model</span> shows that there is no conflict between an appreciable N-N oscillation and the observed baryon to entropy ratio of the universe. Alexander von Humboldt Fellow. Also at the Physics Department, University of Munich (Fed. Rep. Germany) on sabbatical leave from City College of City University of New York, NY, USA. Work supported in part by US National Science Foundation and CUNY-PSCBHE Award No. RF 13406.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoJI.204.1266H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoJI.204.1266H"><span><span class="hlt">Model</span> parameter estimation bias induced by <span class="hlt">earthquake</span> magnitude cut-off</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Harte, D. S.</p> <p>2016-02-01</p> <p>We evaluate the bias in parameter estimates of the ETAS <span class="hlt">model</span>. We show that when a simulated catalogue is magnitude-truncated there is considerable bias, whereas when it is not truncated there is no discernible bias. We also discuss two further implied assumptions in the ETAS and other self-exciting <span class="hlt">models</span>. First, that the triggering boundary magnitude is equivalent to the catalogue completeness magnitude. Secondly, the assumption in the Gutenberg-Richter relationship that numbers of events increase exponentially as magnitude decreases. These two assumptions are confounded with the magnitude truncation effect. We discuss the effect of these problems on analyses of real <span class="hlt">earthquake</span> catalogues.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016GeoRL..43.7902L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016GeoRL..43.7902L"><span><span class="hlt">Modeling</span> tsunami observations to evaluate a proposed late tsunami <span class="hlt">earthquake</span> stage for the 16 September 2015 Illapel, Chile, Mw 8.3 <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>Lay, Thorne; Li, Linyan; Cheung, Kwok Fai</p> <p>2016-08-01</p> <p>Resolving seaward extent of slip during great subduction zone interplate ruptures using land-based seismological and geodetic observations is challenging. <span class="hlt">Modeling</span> of tsunami recordings from ocean-bottom pressure sensors of the Deep-ocean Assessment and Reporting of Tsunami (DART) network has added valuable constraints on near-trench slip for recent events. We use DART and tide gauge recordings to evaluate a proposed seismological scenario involving a late Mw 8.08 tsunami <span class="hlt">earthquake</span> following the 95 s long main rupture stage of the 16 September 2015 Illapel, Chile, Mw 8.3 <span class="hlt">earthquake</span>. Tsunami observations constrain the spatial extent of any late tsunami <span class="hlt">earthquake</span> slip to locate north of the main shock hypocenter. The proposed late shallow slip predicts tsunami signals with considerable amplitudes but shorter wavelengths compared to those of the main stage slip constrained by joint seismic and tsunami <span class="hlt">modeling</span>, yielding overprediction of first-arrival amplitudes at DART and tide gauge stations when the two stages are combined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..1413297A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..1413297A"><span>Empirical testing of <span class="hlt">earthquake</span> recurrence <span class="hlt">models</span> at source and site</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Albarello, D.; Mucciarelli, M.</p> <p>2012-04-01</p> <p>Several probabilistic procedures are presently available for seismic hazard assessment (PSHA), based on time-dependent or time-independent <span class="hlt">models</span>. The result is a number of different outcomes (hazard maps), and to take into account the inherent uncertainty (epistemic), the outcomes of alternative procedures are combined in the frame of logic-tree approaches by scoring each procedure as a function of the respective reliability. This is deduced by evaluating ex-ante (by expert judgements) each element concurring in the relevant PSH computational procedure. This approach appears unsatisfactory also because the value of each procedure depends both on the reliability of each concurring element and on that of their combination: thus, checking the correctness of single elements does not allow evaluating the correctness of the procedure as a whole. Alternative approaches should be based 1) on the ex-post empirical testing of the considered PSH computational <span class="hlt">models</span> and 2) on the validation of the assumptions underlying concurrent <span class="hlt">models</span>. The first goal can be achieved comparing the probabilistic forecasts provided by each <span class="hlt">model</span> with empirical evidence relative to seismic occurrences (e.g., strong-motion data or macroseismic intensity evaluations) during some selected control periods of dimension comparable with the relevant exposure time. About assumptions validation, critical issues are the dimension of the minimum data set necessary to distinguish processes with or without memory, the reliability of mixed data on seismic sources (i.e. historical and palaeoseismological), the completeness of fault catalogues. Some results obtained by the application of these testing procedures in Italy will be shortly outlined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013AGUFM.S51F..04F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013AGUFM.S51F..04F"><span>Overview of the Uniform California <span class="hlt">Earthquake</span> Rupture Forecast Version 3 (UCERF3) Time-Independent <span class="hlt">Model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Field, E. H.; Arrowsmith, R.; Biasi, G. P.; Bird, P.; Dawson, T. E.; Felzer, K. R.; Jackson, D. D.; Johnson, K. M.; Jordan, T. H.; Madugo, C. M.; Michael, A. J.; Milner, K. R.; Page, M. T.; Parsons, T.; Powers, P.; Shaw, B. E.; Thatcher, W. R.; Weldon, R. J.; Zeng, Y.</p> <p>2013-12-01</p> <p>We present the time-independent component of the Uniform California <span class="hlt">Earthquake</span> Rupture Forecast, Version 3 (UCERF3), where the primary achievements have been to relax fault segmentation and include multi-fault ruptures, both limitations of UCERF2. The rates of all <span class="hlt">earthquakes</span> are solved for simultaneously, and from a broader range of data, using a system-level 'grand inversion' that is both conceptually simple and extensible. The inverse problem is large and underdetermined, so a range of <span class="hlt">models</span> is sampled using an efficient simulated annealing algorithm. The approach is more derivative than prescriptive (e.g., magnitude-frequency distributions are no longer assumed), so new analysis tools were developed for exploring solutions. Epistemic uncertainties were also accounted for using 1440 alternative logic tree branches, necessitating access to supercomputers. The most influential uncertainties include alternative deformation <span class="hlt">models</span> (fault slip rates), a new smoothed seismicity algorithm, alternative values for the total rate of M≥5 events, and different scaling relationships, virtually all of which are new. As a notable first, three deformation <span class="hlt">models</span> are based on kinematically consistent inversions of geodetic and geologic data, also providing slip-rate constraints on faults previously excluded due to lack of geologic data. The grand inversion constitutes a system-level framework for testing hypotheses and balancing the influence of different experts. For example, we demonstrate serious challenges with the Gutenberg-Richter hypothesis for individual faults. UCERF3 is still an approximation of the system, however, and the range of <span class="hlt">models</span> is limited (e.g., constrained to stay close to UCERF2). Nevertheless, UCERF3 removes the apparent UCERF2 over-prediction of M6.5-7 <span class="hlt">earthquake</span> rates, and also includes types of multi-fault ruptures seen in nature. While UCERF3 fits the data better than UCERF2 overall, there may be areas that warrant further site</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Ge%26Ae..55..626S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Ge%26Ae..55..626S"><span>Electrodynamic <span class="hlt">model</span> of atmospheric and ionospheric processes on the eve of an <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>Sorokin, V. M.; Ruzhin, Yu. Ya.</p> <p>2015-09-01</p> <p>Electric field generation and its accompanying phenomena in the atmosphere-ionosphere system have been intensively studied in recent years. This paper considers the results of these studies, which have served as the physical basis for the <span class="hlt">model</span> of lithosphere-ionosphere coupling. According to our <span class="hlt">model</span>, the intensive processes in the lower atmosphere and lithosphere have an electrodynamic effect on the ionospheric plasma. The <span class="hlt">model</span> was used to conduct theoretical studies of plasma and electromagnetic effects accompanying the generation of conduction current in the global circuit. It has been shown that the electrodynamic <span class="hlt">model</span> of the influence of seismic and meteorological processes on cosmic plasma can serve as a physical basis for a satellite system to monitor <span class="hlt">earthquake</span> precursors and the catastrophic phase of typhoon development. The <span class="hlt">model</span> makes it possible to couple the satellite data of electromagnetic and plasma measurements with electrophysical and meteorological characteristics of the lower atmosphere at the stage of <span class="hlt">earthquake</span> preparation and typhoon initiation. The <span class="hlt">model</span> suggests that the numerous effects in the cosmic plasma have a single source: a change in the conduction current flowing in the atmosphere-ionosphere circuit.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.S23C2758A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.S23C2758A"><span>Velocity Structure in the West Bohemia Seismic Zone: Velocity <span class="hlt">Models</span> Retrieved from different <span class="hlt">Earthquake</span> Swarms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alexandrakis, C.; Löberich, E.; Kieslich, A.; Calo, M.; Vavrycuk, V.; Buske, S.</p> <p>2015-12-01</p> <p><span class="hlt">Earthquake</span> swarms, fluid migration and gas springs are indications of the ongoing geodynamic processes within the West Bohemia seismic zone located at the Czech-German border. The possible relationship between the fluids, gas and seismicity is of particular interest and has motivated numerous past, ongoing and future studies, including a multidisciplinary monitoring proposal through the International Continental Scientific Drilling Program (ICDP). The most seismically active area within the West Bohemia seismic zone is located at the Czech town Nový Kostel. The Nový Kostel zone experiences frequent swarms of several hundreds to thousands of <span class="hlt">earthquakes</span> over a period of weeks to several months. The seismicity is always located in the same area and depth range (~5-15 km), however the activated fault segments and planes differ. For example, the 2008 swarm activated faults along the southern end of the seismic zone, the 2011 swarm activated the northern segment, and the recent 2014 swarm activated the middle of the seismic zone. This indicates changes to the local stress field, and may relate to fluid migration and/or the complicated tectonic situation. The West Bohemia Seismic Network (WEBNET) is ideally located for studying the Nový Kostel swarm area and provides good azimuthal coverage. Here, we use the high quality P- and S-wave arrival picks recorded by WEBNET to calculate swarm-dependent velocity <span class="hlt">models</span> for the 2008 and 2011 swarms, and an averaged (swarm independent) <span class="hlt">model</span> using <span class="hlt">earthquakes</span> recorded between 1991 and 2011. To this end, we use double-difference tomography to calculate P- and S-wave velocity <span class="hlt">models</span>. The <span class="hlt">models</span> are compared and examined in terms of swarm-dependent velocities and structures. Since the P-to-S velocity ratio is particularly sensitive to the presence of pore fluids, we derive ratio <span class="hlt">models</span> directly from the inverted P- and S-wave <span class="hlt">models</span> in order to investigate the potential influence of fluids on the seismicity. Finally, clustering</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006CNSNS..11..685G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006CNSNS..11..685G"><span><span class="hlt">Non-conservative</span> oscillations of a tool for deep hole honing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gouskov, Alexander M.; Voronov, Sergey A.; Butcher, Eric A.; Sinha, S. C.</p> <p>2006-09-01</p> <p>The dynamics of a rotating tool, commonly employed in deep hole honing, is considered. A mathematical <span class="hlt">model</span> of the process including a dynamic representation of tool, workpiece surface and honing stones interaction is suggested and analyzed. It is shown that interaction forces are <span class="hlt">non-conservative</span>. The honing tool is <span class="hlt">modeled</span> as a rotating continuous slender beam with a mandrel attached at an intermediate cross-section. The transverse oscillations of tool shaft cause variation in expansion pressure and change the interaction forces on the surface of the workpiece. The interaction forces are nonlinear and <span class="hlt">non-conservative</span> in the general case including delayed functions. The expansion pressure of stones turns out to be a critical parameter in a honing process. Since the removal of stock increases linearly with pressure, the productivity can be improved by increasing expansion pressure, but in certain conditions may cause dynamic instability of the tool shaft. On the other hand, the lower expansion pressure and feed rates increase accuracy. Another source of shaft instability is due to the asymmetry of the tool that leads to discrepancy of the system stiffness in the transverse directions. As a result, under certain conditions unstable parametric vibrations may occur. Needless to say, the dynamic behavior of the tool can considerably influence the machined surface formation. In this study a <span class="hlt">model</span> of honing surface formation is introduced and integrated into the <span class="hlt">model</span> of process simulation. The system response is studied for different parameters in a non-dimensional form. Thus it is possible to analyze a set of real processes by applying the similarity conditions. The variation in the machined surface having various initial discrepancies from ideal cylinder is also analyzed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.T41A4593S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.T41A4593S"><span>Extended friction to flow laws and their applications to fault <span class="hlt">models</span> and <span class="hlt">earthquake</span> <span class="hlt">modeling</span> across the lithosphere</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shimamoto, T.; Noda, H.</p> <p>2014-12-01</p> <p>Establishment of a constitutive law from friction to high-temperature plastic flow has long been a task for solving problems such as <span class="hlt">modeling</span> <span class="hlt">earthquakes</span> and plate interactions. Here we propose an empirical constitutive law that describes this transitional behavior using only friction and flow parameters, with good agreements with experimental data on halite shear zones. The law predicts a complete spectrum of steady-state and transient behaviors, including the dependence of the shear resistance of a fault on slip rate, effective normal stress and temperature. The law predicts a change in velocity-weakening to velocity-strengthening with increasing temperature, very similar to the change recognized for granite under hydrothermal conditions. It is surprising that a slight deviation from the steady-state friction law due to the involvement of plastic deformation can cause a large change in the velocity dependence. We solved seismic cycles of a fault across the lithosphere with the friction to flow law using a 2D spectral boundary integral equation method, revealing dynamic rupture extending into the aseismic zone and very rich evolution of interseismic creep including slow slip prior to <span class="hlt">earthquakes</span>. Seismic slip followed by creep is consistent with natural pseudotachylytes overprinted with mylonitic deformation. Our friction-to-flow law merges "Christmas-tree" strength profiles of the lithosphere and rate-dependency fault <span class="hlt">models</span> used for <span class="hlt">earthquake</span> <span class="hlt">modeling</span> on a unified basis. Conventionally strength profiles were drawn assuming a strain rate for the flow regime, but we emphasize that stress distribution evolves reflecting the fault behavior. A fault-zone <span class="hlt">model</span> was updated based on the <span class="hlt">earthquake</span> <span class="hlt">modeling</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPA51A2070G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPA51A2070G"><span>E-DECIDER: Using Earth Science Data and <span class="hlt">Modeling</span> Tools to Develop Decision Support for <span class="hlt">Earthquake</span> Disaster Response</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Glasscoe, M. T.; Donnellan, A.; Parker, J. W.; Stough, T. M.; Burl, M. C.; Pierce, M.; Wang, J.; Ma, Y.; Rundle, J. B.; yoder, M. R.; Bawden, G. W.</p> <p>2012-12-01</p> <p><span class="hlt">Earthquake</span> Data Enhanced Cyber-Infrastructure for Disaster Evaluation and Response (E-DECIDER) is a NASA-funded project developing new capabilities for decision-making utilizing remote sensing data and <span class="hlt">modeling</span> software to provide decision support for <span class="hlt">earthquake</span> disaster management and response. Geodetic imaging data, including from inteferometric synthetic aperture radar (InSAR) and GPS, have a rich scientific heritage for use in <span class="hlt">earthquake</span> research. Survey grade GPS was developed in the 1980s and the first InSAR image of an <span class="hlt">earthquake</span> was produced for the 1992 Landers event. As more of these types of data have become increasingly available they have also shown great utility for providing key information for disaster response. Work has been done to translate these data into useful and actionable information for decision makers in the event of an <span class="hlt">earthquake</span> disaster. In addition to observed data, <span class="hlt">modeling</span> tools provide essential preliminary estimates while data are still being collected and/or processed, which can be refined as data products become available. Now, with more data and better <span class="hlt">models</span>, we are able apply these to responders who need easy tools and routinely produced data products. E-DECIDER incorporates the <span class="hlt">earthquake</span> forecasting methodology and geophysical <span class="hlt">modeling</span> tools developed through NASA's QuakeSim project. Remote sensing and geodetic data, in conjunction with <span class="hlt">modeling</span> and forecasting tools allows us to provide both long-term planning information for disaster management decision makers as well as short-term information following <span class="hlt">earthquake</span> events (i.e. identifying areas where the greatest deformation and damage has occurred and emergency services may need to be focused). E-DECIDER has taken advantage of the legacy of Earth science data, including MODIS, Landsat, SCIGN, PBO, UAVSAR, and <span class="hlt">modeling</span> tools such as the ones developed by QuakeSim, in order to deliver successful decision support products for <span class="hlt">earthquake</span> disaster response. The project has</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70034590','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70034590"><span>Specifying initial stress for dynamic heterogeneous <span class="hlt">earthquake</span> source <span class="hlt">models</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>Andrews, D.J.; Barall, M.</p> <p>2011-01-01</p> <p>Dynamic rupture calculations using heterogeneous stress drop that is random and self-similar with a power-law spatial spectrum have great promise of producing realistic ground-motion predictions. We present procedures to specify initial stress for random events with a target rupture length and target magnitude. The stress function is modified in the depth dimension to account for the brittle-ductile transition at the base of the seismogenic zone. Self-similar fluctuations in stress drop are tied in this work to the long-wavelength stress variation that determines rupture length. Heterogeneous stress is related to friction levels in order to relate the <span class="hlt">model</span> to physical concepts. In a variant of the <span class="hlt">model</span>, there are high-stress asperities with low background stress. This procedure has a number of advantages: (1) rupture stops naturally, not at artificial barriers; (2) the amplitude of short-wavelength fluctuations of stress drop is not arbitrary: the spectrum is fixed to the long-wavelength fluctuation that determines rupture length; and (3) large stress drop can be confined to asperities occupying a small fraction of the total rupture area, producing slip distributions with enhanced peaks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2013/1165/pdf/ofr2013-1165.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2013/1165/pdf/ofr2013-1165.pdf"><span>Uniform California <span class="hlt">earthquake</span> rupture forecast, version 3 (UCERF3): the time-independent <span class="hlt">model</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>Field, Edward H.; Biasi, Glenn P.; Bird, Peter; Dawson, Timothy E.; Felzer, Karen R.; Jackson, David D.; Johnson, Kaj M.; Jordan, Thomas H.; Madden, Christopher; Michael, Andrew J.; Milner, Kevin R.; Page, Morgan T.; Parsons, Thomas; Powers, Peter M.; Shaw, Bruce E.; Thatcher, Wayne R.; Weldon, Ray J.; Zeng, Yuehua; ,</p> <p>2013-01-01</p> <p>In this report we present the time-independent component of the Uniform California <span class="hlt">Earthquake</span> Rupture Forecast, Version 3 (UCERF3), which provides authoritative estimates of the magnitude, location, and time-averaged frequency of potentially damaging <span class="hlt">earthquakes</span> in California. The primary achievements have been to relax fault segmentation assumptions and to include multifault ruptures, both limitations of the previous <span class="hlt">model</span> (UCERF2). The rates of all <span class="hlt">earthquakes</span> are solved for simultaneously, and from a broader range of data, using a system-level "grand inversion" that is both conceptually simple and extensible. The inverse problem is large and underdetermined, so a range of <span class="hlt">models</span> is sampled using an efficient simulated annealing algorithm. The approach is more derivative than prescriptive (for example, magnitude-frequency distributions are no longer assumed), so new analysis tools were developed for exploring solutions. Epistemic uncertainties were also accounted for using 1,440 alternative logic tree branches, necessitating access to supercomputers. The most influential uncertainties include alternative deformation <span class="hlt">models</span> (fault slip rates), a new smoothed seismicity algorithm, alternative values for the total rate of M≥5 events, and different scaling relationships, virtually all of which are new. As a notable first, three deformation <span class="hlt">models</span> are based on kinematically consistent inversions of geodetic and geologic data, also providing slip-rate constraints on faults previously excluded because of lack of geologic data. The grand inversion constitutes a system-level framework for testing hypotheses and balancing the influence of different experts. For example, we demonstrate serious challenges with the Gutenberg-Richter hypothesis for individual faults. UCERF3 is still an approximation of the system, however, and the range of <span class="hlt">models</span> is limited (for example, constrained to stay close to UCERF2). Nevertheless, UCERF3 removes the apparent UCERF2 overprediction of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010PhRvE..81d6117J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010PhRvE..81d6117J"><span>Realistic spatial and temporal <span class="hlt">earthquake</span> distributions in a modified Olami-Feder-Christensen <span class="hlt">model</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jagla, E. A.</p> <p>2010-04-01</p> <p>The Olami-Feder-Christensen <span class="hlt">model</span> describes a limiting case of an elastic surface that slides on top of a substrate and is one of the simplest <span class="hlt">models</span> that display some features observed in actual seismicity patterns. However, temporal and spatial correlations of real <span class="hlt">earthquakes</span> are not correctly described by this <span class="hlt">model</span> in its original form. I propose and study a modified version of the <span class="hlt">model</span>, which includes a mechanism of structural relaxation. With this modification, realistic features of seismicity emerge, which are not obtained with the original version, mainly: aftershocks that cluster spatially around the slip surface of the main shock and follow the Omori law, and averaged frictional properties similar to those observed in rock friction, in particular the velocity-weakening effect. In addition, a Gutenberg-Richter law for the decaying of number of <span class="hlt">earthquakes</span> with magnitude is obtained, with a decaying exponent within the range of experimentally observed values. Contrary to the original version of the <span class="hlt">model</span>, a realistic value of the exponent appears without the necessity to fine tune any parameter.</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/2009AGUFM.U23A0016V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.U23A0016V"><span>3D Finite Element <span class="hlt">Modeling</span> of the 2009 L'Aquila <span class="hlt">Earthquake</span> Deformation Field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Volpe, M.; Casarotti, E.; Piersanti, A.</p> <p>2009-12-01</p> <p>The L'Aquila <span class="hlt">earthquake</span> (Mw 6.3) occurred on April 6th at 01:32 UTC in the Central Appennines at a depth of about 9 km and was felt all over Central Italy. The main shock was preceded by a long seismic sequence started several months before and was followed by thousands of aftershocks, some of them with Mw>4. We built up a high resolution three-dimensional <span class="hlt">model</span>, incorporating surface topography, which was discretized using 20-nodes brick elements. The element horizontal size is biased from 500 m to 2 km using the paving meshing algorithm in combination with an appropriate adaptive sizing function. A realistic rheology was introduced from a vp/vpvs travel time tomographic <span class="hlt">model</span>. We computed the co-seismic deformation induced by the <span class="hlt">earthquake</span> by means of a recently developed finite elements simulation tool, FEMSA (Finite Element <span class="hlt">Modeling</span> for Seismic Applications). We used different seismic source <span class="hlt">models</span> obtained from fault inversion of GPS measurements, joint inversion of strong motion and GPS data and from inversion of DInSAR displacements. The synthetic deformation patterns were compared with the experimental results in order to evaluate which source <span class="hlt">model</span> better reconciles the data and quantify the trade off introduced by 1D simulations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AcGeo..64.2136G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AcGeo..64.2136G"><span>Analysis of Coseismic Fault Slip <span class="hlt">Models</span> of the 2012 Indian Ocean <span class="hlt">Earthquake</span>: Importance of GPS Data for Crustal Deformation Studies</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gunawan, Endra; Maulida, Putra; Meilano, Irwan; Irsyam, Masyhur; Efendi, Joni</p> <p>2016-12-01</p> <p>Based on continuous GPS data, we analyze coseismic deformation due to the 2012 Indian Ocean <span class="hlt">earthquake</span>. We use the available coseismic slip <span class="hlt">models</span> of the 2012 <span class="hlt">earthquake</span>, derived from geodetic and/or seismic waveform inversion, to calculate the coseismic displacements in the Andaman-Nicobar, Sumatra and Java. In our analysis, we employ a spherical, layered <span class="hlt">model</span> of the Earth and we find that Java Island experienced coseismic displacements up to 8 mm, as also observed by our GPS network. Compared to coseismic offsets measured from GPS data, a coseismic slip <span class="hlt">model</span> derived from multiple observations produced better results than a <span class="hlt">model</span> based on a single type of observation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70030112','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70030112"><span>Coseismic source <span class="hlt">model</span> of the 2003 Mw 6.8 Chengkung <span class="hlt">earthquake</span>, Taiwan, determined from GPS measurements</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Ching, K.-E.; Rau, R.-J.; Zeng, Y.</p> <p>2007-01-01</p> <p>A coseismic source <span class="hlt">model</span> of the 2003 Mw 6.8 Chengkung, Taiwan, <span class="hlt">earthquake</span> was well determined with 213 GPS stations, providing a unique opportunity to study the characteristics of coseismic displacements of a high-angle buried reverse fault. Horizontal coseismic displacements show fault-normal shortening across the fault trace. Displacements on the hanging wall reveal fault-parallel and fault-normal lengthening. The largest horizontal and vertical GPS displacements reached 153 and 302 mm, respectively, in the middle part of the network. Fault geometry and slip distribution were determined by inverting GPS data using a three-dimensional (3-D) layered-elastic dislocation <span class="hlt">model</span>. The slip is mainly concentrated within a 44 ?? 14 km slip patch centered at 15 km depth with peak amplitude of 126.6 cm. Results from 3-D forward-elastic <span class="hlt">model</span> tests indicate that the dome-shaped folding on the hanging wall is reproduced with fault dips greater than 40??. Compared with the rupture area and average slip from slow slip <span class="hlt">earthquakes</span> and a compilation of finite source <span class="hlt">models</span> of 18 <span class="hlt">earthquakes</span>, the Chengkung <span class="hlt">earthquake</span> generated a larger rupture area and a lower stress drop, suggesting lower than average friction. Hence the Chengkung <span class="hlt">earthquake</span> seems to be a transitional example between regular and slow slip <span class="hlt">earthquakes</span>. The coseismic source <span class="hlt">model</span> of this event indicates that the Chihshang fault is divided into a creeping segment in the north and the locked segment in the south. An average recurrence interval of 50 years for a magnitude 6.8 <span class="hlt">earthquake</span> was estimated for the southern fault segment. Copyright 2007 by the American Geophysical Union.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1918676C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1918676C"><span>Impact of great subduction <span class="hlt">earthquakes</span> on the long-term forearc morphology, insight from mechanical <span class="hlt">modelling</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cubas, Nadaya</p> <p>2017-04-01</p> <p>The surge of great subduction <span class="hlt">earthquakes</span> during the last fifteen years provided numerous observations requiring revisiting our understanding of large seismic events mechanics. For instance, we now have clear evidence that a significant part of the upper plate deformation is permanently acquired. The link between great <span class="hlt">earthquakes</span> and long-term deformation offers a new perspective for the relief construction understanding. In addition, a better understanding of these relations could provide us with new constraints on <span class="hlt">earthquake</span> mechanics. It is also of fundamental importance for seismic risk assessment. In this presentation, I will compile recent results obtained from mechanical <span class="hlt">modelling</span> linking megathrust ruptures with upper-plate permanent deformation and discuss their impact. We will first show that, in good accordance with lab experiments, aseismic zones are characterized by frictions larger or equal to 0.1 whereas seismic asperities have dynamic frictions lower than 0.05. This difference will control the long-term upper-plate morphology. The larger values along aseismic zones allow the wedge to reach the critical state, and will lead to active thrust systems forming a relief. On the contrary, low dynamic friction along seismic asperities will place the taper in the sub-critical domain impeding any internal deformation. This will lead to the formation of forearc basins inducing negative gravity anomalies. Since aseismic zones have higher friction and larger taper, fully creeping segments will tend to develop peninsulas. On the contrary, fully locked segments with low dynamic friction and very low taper will favor subsiding coasts. The taper variation due to megathrust friction is also expressed through a correlation between coast-to-trench distance and forearc coupling (e.g., Mexican and South-American subduction zones). We will then discuss how variations of frictional properties along the megathrust can induce splay fault activation. For instance, we can</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1918205C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1918205C"><span>The 2016 central Italy <span class="hlt">earthquake</span> sequence: surface effects, fault <span class="hlt">model</span> and triggering scenarios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chatzipetros, Alexandros; Pavlides, Spyros; Papathanassiou, George; Sboras, Sotiris; Valkaniotis, Sotiris; Georgiadis, George</p> <p>2017-04-01</p> <p>The results of fieldwork performed during the 2016 <span class="hlt">earthquake</span> sequence around the karstic basins of Norcia and La Piana di Castelluccio, at an altitude of 1400 m, on the Monte Vettore (altitude 2476 m) and Vettoretto, as well as the three mapped seismogenic faults, striking NNW-SSW, are presented in this paper. Surface co-seismic ruptures were observed in the Vettore and Vettoretto segment of the fault for several kilometres ( 7 km) in the August <span class="hlt">earthquakes</span> at high altitudes, and were re-activated and expanded northwards during the October <span class="hlt">earthquakes</span>. Coseismic ruptures and the neotectonic Mt. Vettore fault zone were <span class="hlt">modelled</span> in detail using images acquired from specifically planned UAV (drone) flights. Ruptures, typically with displacement of up to 20 cm, were observed after the August event both in the scree and weathered mantle (elluvium), as well as the bedrock, consisting mainly of fragmented carbonate rocks with small tectonic surfaces. These fractures expanded and new ones formed during the October events, typically of displacements of up to 50 cm, although locally higher displacements of up to almost 2 m were observed. Hundreds of rock falls and landslides were mapped through satellite imagery, using pre- and post- <span class="hlt">earthquake</span> Sentinel 2A images. Several of them were also verified in the field. Based on field mapping results and seismological information, the causative faults were <span class="hlt">modelled</span>. The <span class="hlt">model</span> consists of five seismogenic sources, each one associated with a strong event in the sequence. The visualisation of the seismogenic sources follows INGV's DISS standards for the Individual Seismogenic Sources (ISS) layer, while strike, dip and rake of the seismic sources are obtained from selected focal mechanisms. Based on this <span class="hlt">model</span>, the ground deformation pattern was inferred, using Okada's dislocation solution formulae, which shows that the maximum calculated vertical displacement is 0.53 m. This is in good agreement with the statistical analysis of the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26677132','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26677132"><span>Wetting of <span class="hlt">nonconserved</span> residue-backbones: A feature indicative of aggregation associated regions of proteins.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pradhan, Mohan R; Pal, Arumay; Hu, Zhongqiao; Kannan, Srinivasaraghavan; Chee Keong, Kwoh; Lane, David P; Verma, Chandra S</p> <p>2016-02-01</p> <p>Aggregation is an irreversible form of protein complexation and often toxic to cells. The process entails partial or major unfolding that is largely driven by hydration. We <span class="hlt">model</span> the role of hydration in aggregation using "Dehydrons." "Dehydrons" are unsatisfied backbone hydrogen bonds in proteins that seek shielding from water molecules by associating with ligands or proteins. We find that the residues at aggregation interfaces have hydrated backbones, and in contrast to other forms of protein-protein interactions, are under less evolutionary pressure to be conserved. Combining evolutionary conservation of residues and extent of backbone hydration allows us to distinguish regions on proteins associated with aggregation (<span class="hlt">non-conserved</span> dehydron-residues) from other interaction interfaces (conserved dehydron-residues). This novel feature can complement the existing strategies used to investigate protein aggregation/complexation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AIPC.1441..555A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AIPC.1441..555A"><span>The FrPNC experiment at TRIUMF: Atomic parity <span class="hlt">non-conservation</span> in francium</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aubin, S.; Gomez, E.; Behr, J. A.; Pearson, M. R.; Sheng, D.; Zhang, J.; Collister, R.; Melconian, D.; Flambaum, V. V.; Sprouse, G. D.; Orozco, L. A.; Gwinner, G.</p> <p>2012-09-01</p> <p>The FrPNC collaboration has begun the construction of an on-line laser cooling and trapping apparatus at TRIUMF to measure atomic parity <span class="hlt">non-conservation</span> (PNC) and the nuclear anapole moment in a string of artificially produced francium isotopes. Atomic PNC experiments provide unique high precision tests of the electroweak sector of the Standard <span class="hlt">Model</span> at very low energies. Furthermore, precision measurements of spin-dependent atomic PNC can determine nuclear anapole moments and probe the weak force within the nucleus. Francium is an excellent candidate for precision measurements of atomic PNC due to its simple electronic structure and enhanced parity violation: both the optical PNC and anapole moment signals are expected to be over an order of magnitude larger than in cesium.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/ds/ds-91/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/ds/ds-91/"><span>Depth to the Juan De Fuca slab beneath the Cascadia subduction margin - a 3-D <span class="hlt">model</span> for sorting <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>McCrory, Patricia A.; Blair, J. Luke; Oppenheimer, David H.; Walter, Stephen R.</p> <p>2004-01-01</p> <p>We present an updated <span class="hlt">model</span> of the Juan de Fuca slab beneath southern British Columbia, Washington, Oregon, and northern California, and use this <span class="hlt">model</span> to separate <span class="hlt">earthquakes</span> occurring above and below the slab surface. The <span class="hlt">model</span> is based on depth contours previously published by Fluck and others (1997). Our <span class="hlt">model</span> attempts to rectify a number of shortcomings in the original <span class="hlt">model</span> and update it with new work. The most significant improvements include (1) a gridded slab surface in geo-referenced (ArcGIS) format, (2) continuation of the slab surface to its full northern and southern edges, (3) extension of the slab surface from 50-km depth down to 110-km beneath the Cascade arc volcanoes, and (4) revision of the slab shape based on new seismic-reflection and seismic-refraction studies. We have used this surface to sort <span class="hlt">earthquakes</span> and present some general observations and interpretations of seismicity patterns revealed by our analysis. For example, deep <span class="hlt">earthquakes</span> within the Juan de Fuca Plate beneath western Washington define a linear trend that may mark a tear within the subducting plate Also <span class="hlt">earthquakes</span> associated with the northern stands of the San Andreas Fault abruptly terminate at the inferred southern boundary of the Juan de Fuca slab. In addition, we provide files of <span class="hlt">earthquakes</span> above and below the slab surface and a 3-D animation or fly-through showing a shaded-relief map with plate boundaries, the slab surface, and hypocenters for use as a visualization tool.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23703864','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23703864"><span>Rare <span class="hlt">nonconservative</span> LRP6 mutations are associated with metabolic syndrome.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Singh, Rajvir; Smith, Emily; Fathzadeh, Mohsen; Liu, Wenzhong; Go, Gwang-Woong; Subrahmanyan, Lakshman; Faramarzi, Saeed; McKenna, William; Mani, Arya</p> <p>2013-09-01</p> <p>A rare mutation in LRP6 has been shown to underlie autosomal dominant coronary artery disease (CAD) and metabolic syndrome in an Iranian kindred. The prevalence and spectrum of LRP6 mutations in the disease population of the United States is not known. Two hundred white Americans with early onset familial CAD and metabolic syndrome and 2,000 healthy Northern European controls were screened for <span class="hlt">nonconservative</span> mutations in LRP6. Three novel mutations were identified, which cosegregated with the metabolic traits in the kindreds of the affected subjects and none in the controls. All three mutations reside in the second propeller domain, which plays a critical role in ligand binding. Two of the mutations substituted highly conserved arginines in the second YWTD domain and the third substituted a conserved glycosylation site. The functional characterization of one of the variants showed that it impairs Wnt signaling and acts as a loss of function mutation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JDE...260..517K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JDE...260..517K"><span><span class="hlt">Non-conservative</span> perturbations of homoclinic snaking scenarios</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Knobloch, Jürgen; Vielitz, Martin</p> <p>2016-01-01</p> <p>Homoclinic snaking refers to the continuation of homoclinic orbits to an equilibrium E near a heteroclinic cycle connecting E and a periodic orbit P. Typically homoclinic snaking appears in one-parameter families of reversible, conservative systems. Here we discuss perturbations of this scenario which are both non-reversible and <span class="hlt">non-conservative</span>. We treat this problem analytically in the spirit of the work [3]. The continuation of homoclinic orbits happens with respect to both the original continuation parameter μ and the perturbation parameter λ. The continuation curves are parametrised by the dwelling time L of the homoclinic orbit near P. It turns out that λ (L) tends to zero while the μ vs. L diagram displays isolas or criss-cross snaking curves in a neighbourhood of the original snakes-and-ladder structure. In the course of our studies we adapt both Fenichel coordinates near P and the analysis of Shilnikov problems near P to the present situation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/21537355','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/21537355"><span>Parity <span class="hlt">nonconservation</span> in odd isotopes of single trapped atomic ions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sahoo, B. K.; Mandal, P.; Mukherjee, M.</p> <p>2011-03-15</p> <p>We have estimated the size of the light shifts due to parity-<span class="hlt">nonconservation</span> (PNC) interactions in different isotopes of Ba{sup +} and Ra{sup +} ions based on the work of Fortson [Phys. Rev. Lett. 70, 2383 (1993)]. We have used the nuclear-spin-independent (NSI) amplitudes calculated earlier by us [Phys. Rev. Lett. 96, 163003 (2006); Phys. Rev. A 78, 050501(R) (2008)], and we have employed the third-order many-body perturbation theory [MBPT(3)] in this work to estimate the nuclear-spin-dependent (NSD) amplitudes in these ions. Ra{sup +} is found to be more favorable than Ba{sup +} for measuring both the NSI and NSD PNC observables.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150006936&hterms=machines&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmachines','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150006936&hterms=machines&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmachines"><span>Integrating Machine Learning into a Crowdsourced <span class="hlt">Model</span> for <span class="hlt">Earthquake</span>-Induced Damage Assessment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rebbapragada, Umaa; Oommen, Thomas</p> <p>2011-01-01</p> <p>On January 12th, 2010, a catastrophic 7.0M <span class="hlt">earthquake</span> devastated the country of Haiti. In the aftermath of an <span class="hlt">earthquake</span>, it is important to rapidly assess damaged areas in order to mobilize the appropriate resources. The Haiti damage assessment effort introduced a promising <span class="hlt">model</span> that uses crowdsourcing to map damaged areas in freely available remotely-sensed data. This paper proposes the application of machine learning methods to improve this <span class="hlt">model</span>. Specifically, we apply work on learning from multiple, imperfect experts to the assessment of volunteer reliability, and propose the use of image segmentation to automate the detection of damaged areas. We wrap both tasks in an active learning framework in order to shift volunteer effort from mapping a full catalog of images to the generation of high-quality training data. We hypothesize that the integration of machine learning into this <span class="hlt">model</span> improves its reliability, maintains the speed of damage assessment, and allows the <span class="hlt">model</span> to scale to higher data volumes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017IJMPC..2850092P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017IJMPC..2850092P"><span>A fragmentation <span class="hlt">model</span> of <span class="hlt">earthquake</span>-like behavior in internet access activity</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Paguirigan, Antonino A.; Angco, Marc Jordan G.; Bantang, Johnrob Y.</p> <p></p> <p>We present a fragmentation <span class="hlt">model</span> that generates almost any inverse power-law size distribution, including dual-scaled versions, consistent with the underlying dynamics of systems with <span class="hlt">earthquake</span>-like behavior. We apply the <span class="hlt">model</span> to explain the dual-scaled power-law statistics observed in an Internet access dataset that covers more than 32 million requests. The non-Poissonian statistics of the requested data sizes m and the amount of time τ needed for complete processing are consistent with the Gutenberg-Richter-law. Inter-event times δt between subsequent requests are also shown to exhibit power-law distributions consistent with the generalized Omori law. Thus, the dataset is similar to the <span class="hlt">earthquake</span> data except that two power-law regimes are observed. Using the proposed <span class="hlt">model</span>, we are able to identify underlying dynamics responsible in generating the observed dual power-law distributions. The <span class="hlt">model</span> is universal enough for its applicability to any physical and human dynamics that is limited by finite resources such as space, energy, time or opportunity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.2082C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.2082C"><span>Stochastic Finite-Fault <span class="hlt">Modeling</span> of Ground Motions from the 2016 Meinong Taiwan <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>Chen, ChunTe; Chang, ShunChiang; Wen, KuoLiang</p> <p>2017-04-01</p> <p>We applied the stochastic method for the finite-fault <span class="hlt">modeling</span> of strong ground motions to the 2016 Meinong, Taiwan <span class="hlt">earthquake</span>. Newly developed attenuation <span class="hlt">models</span> in Southern Taiwan with the frequency-dependent Q=86.42f0.7307and the high-frequency decay factor κ0 were used in the synthetic <span class="hlt">model</span>. The horizontal to vertical spectra ratios (HVSR) were calculated from weak motions and the Meinong mainshock, and were used for the site amplification correction of the synthetic waveforms produced by stochastic ground motion simulation. Simulations incorporating the attenuation <span class="hlt">models</span> and site correction exhibited satisfactory improvement in predicting the S-wave envelope, duration, and peak ground acceleration (PGA). Based on the residual analysis, forward directivity was identified in a 105˚ range in the northwestward direction. The amplification of forward rupture directivity was about three times greater than backward rupture directivity. The result indicated the source rupture directivity effect play an important role may dominate the characteristic of strong ground motions and caused the anomalously strong shake during Meinong <span class="hlt">earthquake</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150006936&hterms=machine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmachine','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150006936&hterms=machine&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dmachine"><span>Integrating Machine Learning into a Crowdsourced <span class="hlt">Model</span> for <span class="hlt">Earthquake</span>-Induced Damage Assessment</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Rebbapragada, Umaa; Oommen, Thomas</p> <p>2011-01-01</p> <p>On January 12th, 2010, a catastrophic 7.0M <span class="hlt">earthquake</span> devastated the country of Haiti. In the aftermath of an <span class="hlt">earthquake</span>, it is important to rapidly assess damaged areas in order to mobilize the appropriate resources. The Haiti damage assessment effort introduced a promising <span class="hlt">model</span> that uses crowdsourcing to map damaged areas in freely available remotely-sensed data. This paper proposes the application of machine learning methods to improve this <span class="hlt">model</span>. Specifically, we apply work on learning from multiple, imperfect experts to the assessment of volunteer reliability, and propose the use of image segmentation to automate the detection of damaged areas. We wrap both tasks in an active learning framework in order to shift volunteer effort from mapping a full catalog of images to the generation of high-quality training data. We hypothesize that the integration of machine learning into this <span class="hlt">model</span> improves its reliability, maintains the speed of damage assessment, and allows the <span class="hlt">model</span> to scale to higher data volumes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1348/','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1348/"><span>Velocity and Density <span class="hlt">Models</span> Incorporating the Cascadia Subduction Zone for 3D <span class="hlt">Earthquake</span> Ground Motion Simulations</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stephenson, William J.</p> <p>2007-01-01</p> <p>INTRODUCTION In support of <span class="hlt">earthquake</span> hazards and ground motion studies in the Pacific Northwest, three-dimensional P- and S-wave velocity (3D Vp and Vs) and density (3D rho) <span class="hlt">models</span> incorporating the Cascadia subduction zone have been developed for the region encompassed from about 40.2?N to 50?N latitude, and from about -122?W to -129?W longitude. The <span class="hlt">model</span> volume includes elevations from 0 km to 60 km (elevation is opposite of depth in <span class="hlt">model</span> coordinates). Stephenson and Frankel (2003) presented preliminary ground motion simulations valid up to 0.1 Hz using an earlier version of these <span class="hlt">models</span>. The version of the <span class="hlt">model</span> volume described here includes more structural and geophysical detail, particularly in the Puget Lowland as required for scenario <span class="hlt">earthquake</span> simulations in the development of the Seattle Urban Hazards Maps (Frankel and others, 2007). Olsen and others (in press) used the <span class="hlt">model</span> volume discussed here to perform a Cascadia simulation up to 0.5 Hz using a Sumatra-Andaman Islands rupture history. As research from the EarthScope Program (http://www.earthscope.org) is published, a wealth of important detail can be added to these <span class="hlt">model</span> volumes, particularly to depths of the upper-mantle. However, at the time of development for this <span class="hlt">model</span> version, no EarthScope-specific results were incorporated. This report is intended to be a reference for colleagues and associates who have used or are planning to use this preliminary <span class="hlt">model</span> in their research. To this end, it is intended that these <span class="hlt">models</span> will be considered a beginning template for a community velocity <span class="hlt">model</span> of the Cascadia region as more data and results become available.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008AGUFM.S31B1911L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008AGUFM.S31B1911L"><span>Focal Depth of the WenChuan <span class="hlt">Earthquake</span> Aftershocks from <span class="hlt">modeling</span> of Seismic Depth Phases</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luo, Y.; Zeng, X.; Chong, J.; Ni, S.; Chen, Y.</p> <p>2008-12-01</p> <p>After the 05/12/2008 great WenChuan <span class="hlt">earthquake</span> in Sichuan Province of China, tens of thousands <span class="hlt">earthquakes</span> occurred with hundreds of them stronger than M4. Those aftershocks provide valuable information about seismotectonics and rupture processes for the mainshock, particularly accurate spatial distribution of aftershocks is very informational for determining rupture fault planes. However focal depth can not be well resolved just with first arrivals recorded by relatively sparse network in Sichuan Province, therefore 3D seismicity distribution is difficult to obtain though horizontal location can be located with accuracy of 5km. Instead local/regional depth phases such as sPmP, sPn, sPL and teleseismic pP,sP are very sensitive to depth, and be readily <span class="hlt">modeled</span> to determine depth with accuracy of 2km. With reference 1D velocity structure resolved from receiver functions and seismic refraction studies, local/regional depth phases such as sPmP, sPn and sPL are identified by comparing observed waveform with synthetic seismograms by generalized ray theory and reflectivity methods. For teleseismic depth phases well observed for M5.5 and stronger events, we developed an algorithm in inverting both depth and focal mechanism from P and SH waveforms. Also we employed the Cut and Paste (CAP) method developed by Zhao and Helmberger i