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Sample records for bam area earthquake

  1. Strong ground motion simulation of the 2003 Bam, Iran, earthquake using the empirical Green's function method

    NASA Astrophysics Data System (ADS)

    Sadeghi, Hossein; Miyake, Hiroe; Riahi, Ali

    2013-04-01

    The 2003 Bam, Iran, earthquake caused catastrophic damage to the city of Bam and neighboring villages. Given its magnitude ( M w ) of 6.5, the damage was remarkably large. Large-amplitude ground motions were recorded at the Bam accelerograph station in the center of Bam city by the Building and Housing Research Center (BHRC) of Iran. We simulated the Bam earthquake acceleration records at three BHRC strong-motion stations—Bam, Abaraq, and Mohammad-Abad—by the empirical Green's function method. Three aftershocks were used as empirical Green's functions. The frequency range of the empirical Green's function simulations was 0.5-10 Hz. The size of the strong motion generation area of the mainshock was estimated to be 11 km in length by 7 km in width. To estimate the parameters of the strong motion generation area, we used 1D and 2D velocity structures across the fault and a combined source model. The empirical Green's function method using a combination of aftershocks produced a source model that reproduced ground motions with the best fit to the observed waveforms. This may be attributed to the existence of two distinct rupture mechanisms in the strong motion generation area. We found that the rupture starting point for which the simulated waveforms best fit the observed ones was near the center of the strong motion generation area, which reproduced near-source ground motions in a broadband frequency range. The estimated strong motion generation area could explain the observed damaging ground motion at the Bam station. This suggests that estimating the source characteristics of the Bam earthquake is very important in understanding the causes of the earthquake damage.

  2. Crisis Management Aspects of Bam Catastrophic Earthquake: Review Article

    PubMed Central

    Sadeghi-Bazargani, Homayoun; Azami-Aghdash, Saber; Kazemi, Abdolhassan; Ziapour, Behrad

    2015-01-01

    Background: Bam earthquake was the most catastrophic natural disasters in recent years. The aim of this study was to review different aspects of crisis management during and after the catastrophic earthquake in Bam City, Iran. Methods: Data needed for this systematic review were collected through searching PubMed, EMBASE and SID databases, for the period from 2003 to 2011. Keywords included earthquake, Iran and Bam earthquake. The data were summarized and were analyzed using Content Analysis. Results: Out of 422 articles, 25 articles were included in the study. Crisis Management aspects and existing pitfalls were classified into seven categories including planning and organization, human resource management, management of logistics, international humanitarian aids, field performance of the military and security forces, health and medical service provision, and information management. Positive aspects and major pitfalls of crisis management have been introduced in all the mentioned categories. Conclusion: The available evidence indicated poor crisis management during Bam earthquake that resulted in aggravating the losses as well as diminishing the effect of interventions. Thus, concerning the importance of different aspects of the crisis management and the high prevalence of disasters in Iran, the observed vulnerability in disaster management process should be addressed. PMID:26000241

  3. Genitourinary system trauma after 2003 Bam earthquake in Kerman, Iran

    PubMed Central

    Dehghani Firoozabadi, Mohammad Hasan; Abedinzadeh, Mehdi; Moslemi, Mohammad Kazem

    2011-01-01

    Background: Natural disasters, especially earthquakes, result in many health problems all over the world, of which urological injuries should not be underestimated. Car accidents and falling from a height are the most common causes of genitourinary system injury. The lack of specific data in the literature regarding the outcome of earthquake-related genitourinary system trauma prompted us to undertake this study. Methods: We retrospectively evaluated the genitourinary system injury in patients who had survived the Bam earthquake. In this study, all patients admitted to two main back-up hospitals of Kerman were included. Of 256 patients who had been referred to Kerman hospitals, 28 cases were found to have urologic damage on physical examination, intravenous pyelography, abdominopelvic X-ray, and ultrasonography. Results: Of 28 patients with urologic damage, 22 (78.5%) were male and six (21.5%) were female. Their age ranged from 18 to 65 years. The injures included urethral disruption in 21 cases (75.5%), vesicovaginal fistula in four cases (14%), kidney rupture in two cases (7%) and bladder neck disruption accompanied with total right ureteral disruption and vesicovaginal fistula in a female patient (3.5%). Conclusion: We have evaluated the incidence of genitourinary injuries after an earthquake disaster for the first time. The most and least common urologic injury in our patients was urethral disruption and ureteral injury, respectively. PMID:21445278

  4. Revisiting blood transfusion preparedness: experience from the Bam earthquake response.

    PubMed

    Abolghasemi, Hassan; Radfar, Mohammad H; Tabatabaee, Morteza; Hosseini-Divkolayee, Nasim S; Burkle, Frederick M

    2008-01-01

    Blood transfusion plays a critical role in the provision of medical care for disasters due to man-made and natural hazards. Although the short-term increase in blood donations following national disasters is well-documented, some aspects of blood transfusion during disasters remain under study. The 2003 earthquake in Bam, Iran resulted in the death of >29,000 people and injured 23,000. In total, 108,985 blood units were donated, but only 21,347 units (23%) actually were distributed to hospitals around the country. Kerman Province, the site of the disaster, received 1,231 (1.3%) of the donated units in the first four days after the disaster. The Bam experience revealed crucial missteps in the development of a post-event strategy for blood product management, and led to the development of a detailed disaster preparedness and response plan that addresses issues of donation, distribution, communication, transportation, and coordination. The current plan requires the Iranian Blood Transfusion Organization to convene a disaster task force immediately as the main coordinator of all disaster preparedness and response activities.

  5. The 2003 Bam (Iran) earthquake: Rupture of a blind strike-slip fault

    NASA Technical Reports Server (NTRS)

    Talebian, M.; Fielding, E. J.; Funning, G. J.; Ghorashi, M.; Jackson, J.; Nazari, H.; Parsons, B.; Priestley, K.; Rosen, P. A.; Walker, R.; Wright, T. J.

    2004-01-01

    A magnitude 6.5 earthquake devastated the town of Bam in southeast Iran on 26 December 2003. Surface displacements and decorrelation effects, mapped using Envisat radar data, reveal that over 2 m of slip occurred at depth on a fault that had not previously been identified. It is common for earthquakes to occur on blind faults which, despite their name, usually produce long-term surface effects by which their existence may be recognised. However, in this case there is a complete absence of morphological features associated with the seismogenic fault that destroyed Bam.

  6. Source Process of the 2003 Bam, Iran, Earthquake: Subsurface Rupture that Generated Extreme Ground Motion

    NASA Astrophysics Data System (ADS)

    Poiata, N.; Miyake, H.; Koketsu, K.; Hikima, K.

    2008-12-01

    The Bam earthquake occurred on December 26, 2003 in southeast Iran. This moderate size event (Mw 6.5) caused heavy damage in the city of Bam and killed about 26,000 people. According to previous studies of geodetic data (e.g., Talebian et al., 2004; Wang et al., 2004) and aftershock distribution (Nakamura et al., 2005), the earthquake was caused by a rupture on a previously unknown strike-slip fault. The strong-motion station located inside the heavily damaged area of the city of Bam in vicinity of the fault recorded a PGA of 988 gal in the UD component and two pulses with a dominant frequency of 1 Hz in the horizontal components. This large PGA and the proportion of damage due to this event might be explained by the combination of source directivity effect and large speed of the rupture front over the fault (Bouchon et al., 2005). To estimate the slip pattern in the source rupture area, precise hypocentral depth, and rupture velocity along the fault, we applied the moment tensor analysis as well as the source inversion method developed by Kikuchi and Kanamori (1991) and Kikuchi et al. (2003) to the IRIS broadband teleseismic data. The result of the source inversion shows the slip distribution that confirms a single asperity, as suggested by Yamanaka (2003), with the rupture propagating in S-N direction along an almost vertical strike-slip fault with dimensions of 25 km in length by 20 km in width. The hypocentral depth for the best fit model is estimated to be 8 km. The maximum slip occurred around the hypocenter at depths of 4-10 km; no slip is associated at a shallower depth. This agrees with the result of subsurface rupture and 'shallow slip deficit' obtained from geodetic data by Fialko et al. (2005) and might explain the extreme ground motion observed at the Bam station as being the result of the subsurface faulting on the immature fault. We also determined the rupture velocity that minimizes the residuals between observed and synthetic waveforms to be 2.8 km

  7. General Health Among Parents Who Lost Their Children in the Bam Earthquake

    PubMed Central

    Rashidinejad, Masoumeh; Dehghan, Mahlagha; Tirgari, Batool; Rafiei, Hossein; Iranmanesh, Sedigheh

    2015-01-01

    Aim: Bam earthquake and its profound tragedy of thousands killed has caused emotional and psychological trauma for tens of thousands of people who have survived. This study aimed to investigate general health of parents who lose their children in Bam earthquake 10 years after the earthquake. Method: General health of 166 parents who lost their children in Bam earthquake was assessed using a translated version of General Health Questionnarie-28 items. Results: The mean score of GHQ was 25.63 ± 15.28. Among all domains, the higher mean score belonged to the category of “anxiety/insomnia” and the lower one belonged to the category of “severe depression. The results revealed significant correlation between total GHQ mean score and gender as well as educational level (0.003) Conclusion: Providing reflective narrative environments in which survivors can express their own experiences and feelings about earthquake, their loss and how they cope with it seems to be as an effective approach to identify their psychosocial situation and its influential factors. In such narrative environments special attention should be given to older participants, females and those who are single. PMID:26156934

  8. Being Under the Umbrella of Persistent Grief: Experiences of Survivors of Bam Earthquake.

    PubMed

    Tirgari, Batool; Azzizadeh Forouzi, Mansooreh; Malakian, Lila

    2016-05-01

    The loss of a loved one is a highly stressful event that nearly everyone experiences. Multiple losses can leave relatives feeling overwhelmed or stuck in their grief, a phenomenon commonly referred to as bereavement overload. This study aimed to elucidate the meaning of prolonged grief from the viewpoint of the survivors of the Bam earthquake (Iran, December 2003) 11 years after the earthquake in south eastern Iran. Family members who lost loved ones in the Bam earthquake were considered potential participants. A total of 12 survivors participated in this study. The interviews were analyzed with Ricoeur's phenomenological hermeneutic method. The meaning of prolonged grief was comprehensively understood as "being under the umbrella of persistent grief." This can be divided into four themes: experiencing a divine and painful destiny, experiencing heartbreaking goodbye with loved ones, losing all hopes and dreams, and being in a state of fragile peace. The results in this study suggest survivors of the Bam earthquake grief can be moderated by adequate crisis-related coping resources such as social, cultural, and religious supports. These supports are clearly important to survivors' post-earthquake recovery. PMID:27172233

  9. A Review of Impact of Bam Earthquake on Cutaneous Leishmaniasis and Status: Epidemic of Old Foci, Emergence of New Foci and Changes in Features of the Disease

    PubMed Central

    Aflatoonian, Mohammad Reza; Sharifi, Iraj; Aflatoonian, Bahnaz; Shirzadi, Mohammad Reza; Gouya, Mohammad Mahdi; Kermanizadeh, Alireza

    2016-01-01

    Background: Global findings indicate that incidence rate of cutaneous leishmaniasis (CL) has significantly increased during the past decade, as documented in many countries. This review was aimed to evaluate the trend of CL cases in terms of demographic and clinical characteristics during a decade after the earthquake (2003–2012) compared to the corresponding period before the earthquake in Bam (1993–2003). Methods: Direct smear preparations along with different intrinsic methods were used for detection and identification of the causative agents. Results: Overall, 20999 cases of CL have occurred during the last 20 years (1993–2012), 6731 cases before and 14268 cases after the earthquake (P< 0.001). Conclusions: Following a major earthquake, several risk factors could activate epidemics of cutaneous leishmaniasis in old foci and induce emerging foci in new areas. PMID:27308286

  10. Surface Ruptures and Building Damage of the 2003 Bam, Iran, Earthquake Mapped by Satellite Synthetic Aperture Radar Interferometric Correlation

    NASA Technical Reports Server (NTRS)

    Fielding, Eric J.; Talebian, M.; Rosen, P. A.; Nazari, H.; Jackson, J. A.; Ghorashi, M.; Walker, R.

    2005-01-01

    We use the interferometric correlation from Envisat synthetic aperture radar (SAR) images to map the details of the surface ruptures related to the 26 December 2003 earthquake that devastated Bam, Iran. The main strike-slip fault rupture south of the city of Bam has a series of four segments with left steps shown by a narrow line of low correlation in the coseismic interferogram. This also has a clear expression in the field because of the net extension across the fault. Just south of the city limits, the surface strain becomes distributed over a width of about 500 m, probably because of a thicker layer of soft sedimentary material.

  11. Three-dimensional deformation caused by the Bam, Iran, earthquake and the origin of shallow slip deficit.

    PubMed

    Fialko, Yuri; Sandwell, David; Simons, Mark; Rosen, Paul

    2005-05-19

    Our understanding of the earthquake process requires detailed insights into how the tectonic stresses are accumulated and released on seismogenic faults. We derive the full vector displacement field due to the Bam, Iran, earthquake of moment magnitude 6.5 using radar data from the Envisat satellite of the European Space Agency. Analysis of surface deformation indicates that most of the seismic moment release along the 20-km-long strike-slip rupture occurred at a shallow depth of 4-5 km, yet the rupture did not break the surface. The Bam event may therefore represent an end-member case of the 'shallow slip deficit' model, which postulates that coseismic slip in the uppermost crust is systematically less than that at seismogenic depths (4-10 km). The InSAR-derived surface displacement data from the Bam and other large shallow earthquakes suggest that the uppermost section of the seismogenic crust around young and developing faults may undergo a distributed failure in the interseismic period, thereby accumulating little elastic strain. PMID:15902247

  12. Cutaneous Leishmaniasis in Bam: A Comparative Evaluation of Pre- and Post-Earthquake Years (1999–2008)

    PubMed Central

    Sharifi, I; Nakhaei, N; Aflatoonian, MR; Parizi, M Hakimi; Fekri, AR; Safizadeh, H; Shirzadi, MR; Gooya, MM; Khamesipour, A; Nadim, A

    2011-01-01

    Background: The recent devastating earthquake of December 26 in Bam, 2003 created various risk factors; caused a sharp increase in incidence of anthroponotic cutaneous leishmaniasis (ACL) cases and reached to an epidemic proportion. The objective of this study was to evaluate the status of ACL cases five years before the earthquake compared to the cases occurred five years after the earthquake (1999–2008). Methods: Status of disease was assessed retrospectively for the five years before the earthquake and prospectively for the five years after the earthquake. Identification was confirmed by smear and polymerase chain reaction (PCR). Results: The mean annual incidence of ACL for the period from 1999 to 2003 was 1.9 per 1000 comparing to post earthquake period, which was 7.6 per 1000. Most of the infection was in individuals of <20 years, more frequently in females before the earthquake, whilst in contrast, there was a progressive rise in the number of cases, significantly in male individuals of >20 years (P< 0.0001) in post earthquake era. The anatomical distribution of lesions considerably changed during the two periods. Most of the cases were limited to three zones within the city prior to the earthquake, whereas it was spread throughout different zones after the earthquake. PCR indicated that the CL was due to Leishmania tropica in the city. Conclusion: The results strongly suggest that in natural disasters such as earthquakes various precipitating factors in favor of disease will be created, which in turn provide a suitable condition for propagation of the vector and the transmission of the parasite. PMID:23113072

  13. Source Fault of the Dec.26, 2003 Bam Earthquake (Mw6.5) in Southeastern Iran Inferred From Aftershock Observation Data by Temporal High-Sensitive-Seismograph Network

    NASA Astrophysics Data System (ADS)

    Suzuki, S.; Matsushima, T.; Ito, Y.; Hosseini, S. K.; Nakamura, T.; Arash, J.; Sadeghi, H.; Maleki, M.; Aghda, F.

    2004-05-01

    The Bam earthquake occurred in southeastern Iran at 05:26 A.M.(local time) on December 26, 2003 (epicenter: 29.010N, 58.266E, Mo=6.6x10**18Nm, Mw=6.5; ref.1). The earthquake had strike-slip mechanism (strike=175, dip=85, slip=153; ref.2) and source parameters (focal depth=4km, fault dimension=20kmx15km, Dmax=1.0m, stress drop=3.7MPa; ref.2). The earthquake struck the ancient city of Bam and killed more than 40,000 people. It shows that one third of about 120,000 in population in and around Bam city were killed. The main reason of such a big damage may be caused by weak adobe and brick houses; even so, the damage was too much big. We, therefore, are researching other cause of such a big damage. Taking instruments from Japan for this aim we installed 9 high sensitive seismographs and one accelerograph in and around Bam city on February 6-8, 2004. And we observed aftershocks and continue during one month. Reading P and S arriving times of about 100 aftershocks occurring from February 6 to 10, we determined those preliminary hypocenters and magnitudes. Those epicenters (errors<500m) distribute mainly from northeastern Bam city to south direction with about 20km length. It means that the fault of the main shock passed just under eastern half of Bam city where most of houses and buildings were heavily damaged. This fault is about 4 km away west from Bam fault which is presented in geological map (ref.3). A north-south vertical cross-section of the hypocentral distribution (maybe errors < 1km) shows that most of their depths are shallower than 14km and a seismic gap exists in the laterally middle part of their distribution and shallower than 6 km in depth. The shallow seismic gap may correspond to a main fracture zone as shown in the slip distribution figure proposed by Yamanaka (ref.2). This main fracture occurring shallower than about 6 km in depth must be one of causes of the big damage in Bam. (Reference) ref1:USGS,http://neic.usgs.gov/neis/FM/, ref 2: ERI, U. Tokyo

  14. Very High Resolution Optical Images for Detecting Co-seismic Surface Effects: the Cases of the 2005 Kashmir (Pakistan) and the 2003 Bam (Iran) Earthquakes

    NASA Astrophysics Data System (ADS)

    Chini, M.; Cinti, F. R.; Stramondo, S.

    2008-12-01

    Very High Resolution (VHR) satellite panchromatic image has revealed to be a reliable tool to detect surface effects of natural disasters. This is particularly true whereas the hit territory is a remote land and/or with logistic and security problems. Data from this kind of sensor have a potential for more exhaustive and accurate mapping of the environment with details of sub-meter ground resolution. We show two large earthquake case studies, the 2005 Mw 7.6 Kashmir and the 2003 Mw 6.6 Bam events, both producing significant surface effects as ruptures, landslides and building damages. In order to test the capability of VHR images to recognize and evaluate such features we used panchromatic QuickBird imagery (0.6 m spatial resolution) acquired before and after the events (kindly provided by DigitalGlobe). Concerning the Pakistan we focus on the Muzaffarabad and Balakot areas, both crossed by the earthquake fault and experiencing edifice collapses. Same sort of analysis is performed for the ancient town of Bam. We proceed with: 1. identification on the images of the main rupture trace and of major landslides; 2. generation of a detailed spatial distribution of damage and collapses through a single building automatic classification approach; 3. cross-comparison of the different surface effects. The QuickBird panchromatic images provide a view of the co-seismic features at large scale, revealing complex geometric pattern of the cracks and compressional deformation features. It is possible to detect the lateral sense of movement, and based on the sun shade projection in the images, we infer the facing of the scarp, thus the uplifted side. Regarding point two, if in one hand the use of QuickBird images leads to detect very small details, on the other hand buildings become rather complex structures. Furthermore they may be surrounded by scattering objects making less evident the contrast between the roofs and the ground, thus increasing the difficulties in the

  15. St. Louis Area Earthquake Hazards Mapping Project

    USGS Publications Warehouse

    Williams, Robert A.; Steckel, Phyllis; Schweig, Eugene

    2007-01-01

    St. Louis has experienced minor earthquake damage at least 12 times in the past 200 years. Because of this history and its proximity to known active earthquake zones, the St. Louis Area Earthquake Hazards Mapping Project will produce digital maps that show variability of earthquake hazards in the St. Louis area. The maps will be available free via the internet. They can be customized by the user to show specific areas of interest, such as neighborhoods or transportation routes.

  16. The Emergence of Anthroponotic Cutaneous Leishmaniasis Following the Earthquake in Southern Villages of Bam District, Southeastern Iran, 2010

    PubMed Central

    Aflatoonian, Mohammad Reza; Sharifi, Iraj; Poursmaelian, Somayeh; Hakimi-Parizi, Maryam; Ziaali, Nasser

    2013-01-01

    Background: The objective of this study was to assess the epidemiological characteristics of a new emerging focus of cutaneous leishmaniasis (CL) in southern villages of Bam District, southeastern Iran, 2010. Methods: A house-to- house census survey of 5544 individuals were interviewed and physically examined for the presence of active lesions or scars. Diagnosis was confirmed by direct smears, cultures and identification by PCR. The data were entered into a computer and SPSS ver. 15. Results: Overall, 1.2% of the inhabitants were infected, 0.5% active and 0.7% scars and females were more significantly infected (1.7%) than males (0.8%), (P= 0.003). All age groups were equally affected. Most of the lesions were on the face and majority had single lesion. Most of the cases appeared from 2006 to 2008 during the CL epidemic in the city of Bam. PCR indicated L. tropica as the causative agent. Conclusion: The presence of non-immune individuals along with suitable ecological conditions could induce a new emerging focus of ACL in villages. PMID:23785690

  17. Mapping of earthquakes vulnerability area in Papua

    NASA Astrophysics Data System (ADS)

    Muhammad Fawzy Ismullah, M.; Massinai, Muh. Altin

    2016-05-01

    Geohazard is a geological occurrence which may lead to a huge loss for human. A mitigation of these natural disasters is one important thing to be done properly in order to reduce the risks. One of the natural disasters that frequently occurs in the Papua Province is the earthquake. This study applies the principle of Geospatial and its application for mapping the earthquake-prone area in the Papua region. It uses earthquake data, which is recorded for 36 years (1973-2009), fault location map, and ground acceleration map of the area. The earthquakes and fault map are rearranged into an earthquake density map, as well as an earthquake depth density map and fault density map. The overlaid data of these three maps onto ground acceleration map are then (compiled) to obtain an earthquake unit map. Some districts area, such as Sarmi, Nabire, and Dogiyai, are identified by a high vulnerability index. In the other hand, Waropen, Puncak, Merauke, Asmat, Mappi, and Bouven Digoel area shows lower index. Finally, the vulnerability index in other places is detected as moderate.

  18. Earthquakes

    MedlinePlus

    An earthquake happens when two blocks of the earth suddenly slip past one another. Earthquakes strike suddenly, violently, and without warning at any time of the day or night. If an earthquake occurs in a populated area, it may cause ...

  19. Understanding earthquake hazards in urban areas - Evansville Area Earthquake Hazards Mapping Project

    USGS Publications Warehouse

    Boyd, Oliver S.

    2012-01-01

    The region surrounding Evansville, Indiana, has experienced minor damage from earthquakes several times in the past 200 years. Because of this history and the proximity of Evansville to the Wabash Valley and New Madrid seismic zones, there is concern among nearby communities about hazards from earthquakes. Earthquakes currently cannot be predicted, but scientists can estimate how strongly the ground is likely to shake as a result of an earthquake and are able to design structures to withstand this estimated ground shaking. Earthquake-hazard maps provide one way of conveying such information and can help the region of Evansville prepare for future earthquakes and reduce earthquake-caused loss of life and financial and structural loss. The Evansville Area Earthquake Hazards Mapping Project (EAEHMP) has produced three types of hazard maps for the Evansville area: (1) probabilistic seismic-hazard maps show the ground motion that is expected to be exceeded with a given probability within a given period of time; (2) scenario ground-shaking maps show the expected shaking from two specific scenario earthquakes; (3) liquefaction-potential maps show how likely the strong ground shaking from the scenario earthquakes is to produce liquefaction. These maps complement the U.S. Geological Survey's National Seismic Hazard Maps but are more detailed regionally and take into account surficial geology, soil thickness, and soil stiffness; these elements greatly affect ground shaking.

  20. Earthquakes.

    ERIC Educational Resources Information Center

    Pakiser, Louis C.

    One of a series of general interest publications on science topics, the booklet provides those interested in earthquakes with an introduction to the subject. Following a section presenting an historical look at the world's major earthquakes, the booklet discusses earthquake-prone geographic areas, the nature and workings of earthquakes, earthquake…

  1. Assessing the earthquake hazards in urban areas

    USGS Publications Warehouse

    Hays, W.W.; Gori, P.L.; Kockelman, W.J.

    1988-01-01

    Major urban areas in widely scattered geographic locations across the United States are a t varying degrees of risk from earthquakes. the locations of these urban areas include Charleston, South Carolina; Memphis Tennessee; St.Louis, Missouri; Salt Lake City, Utah; Seattle-Tacoma, Washington; Portland, Oregon; and Anchorage, Alaska; even Boston, Massachusetts, and Buffalo New York, have a history of large earthquakes. Cooperative research during the past decade has focused on assessing the nature and degree of the risk or seismic hazard i nthe broad geographic regions around each urban area. The strategy since the 1970's has been to bring together local, State, and Federal resources to solve the problem of assessing seismic risk. Successfl sooperative programs have been launched in the San Francisco Bay and Los Angeles regions in California and the Wasatch Front region in Utah. 

  2. Earthquake Hazard for Aswan High Dam Area

    NASA Astrophysics Data System (ADS)

    Ismail, Awad

    2016-04-01

    Earthquake activity and seismic hazard analysis are important components of the seismic aspects for very essential structures such as major dams. The Aswan High Dam (AHD) created the second man-made reservoir in the world (Lake Nasser) and is constructed near urban areas pose a high-risk potential for downstream life and property. The Dam area is one of the seismically active regions in Egypt and is occupied with several cross faults, which are dominant in the east-west and north-south. Epicenters were found to cluster around active faults in the northern part of Lake and AHD location. The space-time distribution and the relation of the seismicity with the lake water level fluctuations were studied. The Aswan seismicity separates into shallow and deep seismic zones, between 0 and 14 and 14 and 30 km, respectively. These two seismic zones behave differently over time, as indicated by the seismicity rate, lateral extent, b-value, and spatial clustering. It is characterized by earthquake swarm sequences showing activation of the clustering-events over time and space. The effect of the North African drought (1982 to present) is clearly seen in the reservoir water level. As it decreased and left the most active fault segments uncovered, the shallow activity was found to be more sensitive to rapid discharging than to the filling. This study indicates that geology, topography, lineations in seismicity, offsets in the faults, changes in fault trends and focal mechanisms are closely related. No relation was found between earthquake activity and both-ground water table fluctuations and water temperatures measured in wells located around the Kalabsha area. The peak ground acceleration is estimated in the dam site based on strong ground motion simulation. This seismic hazard analyses have indicated that AHD is stable with the present seismicity. The earthquake epicenters have recently took place approximately 5 km west of the AHD structure. This suggests that AHD dam must be

  3. BAREPP: Earthquake preparedness for the San Francisco Bay area

    USGS Publications Warehouse

    1986-01-01

    The threat of major and damaging earthquakes in California is a fact. How people respond to that threat is a concern shared by many local, state, federal, volunteer and private sector organizations. The Bay Area Regional Earthquake Preparedness Project (BAREPP) promotes comprehensive earthquake preparedness actions by these organizations and provides technical and planning assistance for a variety of programs.

  4. Source Area of the AD 869 Jogan Earthquake, a Possible Predecessor of the 2011 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Namegaya, Y.; Satake, K.; Fujii, Y.; Yamaki, S.

    2011-12-01

    The AD 869 Jogan earthquake is considered to be a possible predecessor of the 2011 Tohoku earthquake. We previously constructed the 869 fault models based on the tsunami deposit, which is distributed up to several km from the present coastlines. Since the 2011 earthquake also inundated several km in Sendai and Ishinomaki plains, we made calculations of the tsunami inundations from additional source models including the 2011 earthquake model and modified 869 models to further constrain the 869 tsunami source. The 869 tsunami deposit distributes 3 km inland from past coastline in Ishinomaki plain (Shishikura et al., 2007), Miyagi prefecture, 4 km inland in Sendai plain (Sawai et al., 2007), and 1.5 km inland in Ukedo river-mouth lowland, Fukushima prefecture (Suzuki et al., 2009). The past coastlines are considered to be about 1-1.5 km inland from the present coastlines in the both plains. We previously calculated tsunami inundation from several types of source models such as outer-rise normal fault, tsunami earthquake (narrow fault near the trench axis), and interplate earthquakes (depth range of 15-46 km). By matching the distribution of the 869 tsunami deposit and calculated inundation area, we proposed an interplate earthquake with fault length of 200 km, width of 100 km, slip amount of 7 m (Mw8.4), and upper depth of 15 km as a model of the 869 earthquake (Satake et al., 2008; Namegaya et al., 2010). This model, as well as the models presented here, should be considered as the lower limit of the earthquake magnitude of the 869 earthquake, because the post 2011 field surveys indicated that the tsunami inundation area exceeded the distribution of the tsunami deposit. For the 2011 earthquake, inversion analyses of tsunami waveforms (Fujii et al., 2011, EPS) indicate that rupture area extends offshore with length of more than 400 km. Slip amounts are estimated to be 20-30 m at the 20 km depth (around the hypocenter), and more than 40 m near the Japan trench. In this

  5. Earthquake Risk Mitigation in the Tokyo Metropolitan area

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Sakai, S.; Kasahara, K.; Nakagawa, S.; Nanjo, K.; Panayotopoulos, Y.; Tsuruoka, H.

    2010-12-01

    Seismic disaster risk mitigation in urban areas constitutes a challenge through collaboration of scientific, engineering, and social-science fields. Examples of collaborative efforts include research on detailed plate structure with identification of all significant faults, developing dense seismic networks; strong ground motion prediction, which uses information on near-surface seismic site effects and fault models; earthquake resistant and proof structures; and cross-discipline infrastructure for effective risk mitigation just after catastrophic events. Risk mitigation strategy for the next greater earthquake caused by the Philippine Sea plate (PSP) subducting beneath the Tokyo metropolitan area is of major concern because it caused past mega-thrust earthquakes, such as the 1703 Genroku earthquake (magnitude M8.0) and the 1923 Kanto earthquake (M7.9) which had 105,000 fatalities. A M7 or greater (M7+) earthquake in this area at present has high potential to produce devastating loss of life and property with even greater global economic repercussions. The Central Disaster Management Council of Japan estimates that the M7+ earthquake will cause 11,000 fatalities and 112 trillion yen (about 1 trillion US$) economic loss. This earthquake is evaluated to occur with a probability of 70% in 30 years by the Earthquake Research Committee of Japan. In order to mitigate disaster for greater Tokyo, the Special Project for Earthquake Disaster Mitigation in the Tokyo Metropolitan Area (2007-2011) was launched in collaboration with scientists, engineers, and social-scientists in nationwide institutions. The results that are obtained in the respective fields will be integrated until project termination to improve information on the strategy assessment for seismic risk mitigation in the Tokyo metropolitan area. In this talk, we give an outline of our project as an example of collaborative research on earthquake risk mitigation. Discussion is extended to our effort in progress and

  6. Education for Earthquake Disaster Prevention in the Tokyo Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Oki, S.; Tsuji, H.; Koketsu, K.; Yazaki, Y.

    2008-12-01

    Japan frequently suffers from all types of disasters such as earthquakes, typhoons, floods, volcanic eruptions, and landslides. In the first half of this year, we already had three big earthquakes and heavy rainfall, which killed more than 30 people. This is not just for Japan but Asia is the most disaster-afflicted region in the world, accounting for about 90% of all those affected by disasters, and more than 50% of the total fatalities and economic losses. One of the most essential ways to reduce the damage of natural disasters is to educate the general public to let them understand what is going on during those desasters. This leads individual to make the sound decision on what to do to prevent or reduce the damage. The Ministry of Education, Culture, Sports, Science and Technology (MEXT), therefore, offered for public subscription to choose several model areas to adopt scientific education to the local elementary schools, and ERI, the Earthquake Research Institute, is qualified to develop education for earthquake disaster prevention in the Tokyo metropolitan area. The tectonic setting of this area is very complicated; there are the Pacific and Philippine Sea plates subducting beneath the North America and the Eurasia plates. The subduction of the Philippine Sea plate causes mega-thrust earthquakes such as the 1703 Genroku earthquake (M 8.0) and the 1923 Kanto earthquake (M 7.9) which had 105,000 fatalities. A magnitude 7 or greater earthquake beneath this area is recently evaluated to occur with a probability of 70 % in 30 years. This is of immediate concern for the devastating loss of life and property because the Tokyo urban region now has a population of 42 million and is the center of approximately 40 % of the nation's activities, which may cause great global economic repercussion. To better understand earthquakes in this region, "Special Project for Earthquake Disaster Mitigation in Tokyo Metropolitan Area" has been conducted mainly by ERI. It is a 4-year

  7. Earthquakes

    USGS Publications Warehouse

    Shedlock, Kaye M.; Pakiser, Louis Charles

    1998-01-01

    One of the most frightening and destructive phenomena of nature is a severe earthquake and its terrible aftereffects. An earthquake 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 earthquake occurs in a populated area, it may cause many deaths and injuries and extensive property damage. Today we are challenging the assumption that earthquakes must present an uncontrollable and unpredictable hazard to life and property. Scientists have begun to estimate the locations and likelihoods of future damaging earthquakes. Sites of greatest hazard are being identified, and definite progress is being made in designing structures that will withstand the effects of earthquakes.

  8. Small Buildings in Earthquake Areas. Educational Building Digest 2.

    ERIC Educational Resources Information Center

    Mooij, D.

    This booklet is intended for builders and others who actually construct small buildings in earthquake areas and not for professionally qualified architects or engineers. In outline form with sketches the following topics are discussed: general construction and design principles; foundations; earth walls; brick, block, and stone walls; timber frame…

  9. The Bay Area Earthquake Cycle:A Paleoseismic Perspective

    NASA Astrophysics Data System (ADS)

    Schwartz, D. P.; Seitz, G.; Lienkaemper, J. J.; Dawson, T. E.; Hecker, S.; William, L.; Kelson, K.

    2001-12-01

    Stress changes produced by the 1906 San Francisco earthquake had a profound effect on Bay Area seismicity, dramatically reducing it in the 20th century. Whether the San Francisco Bay Region (SFBR) is still within, is just emerging from it, or is out of the 1906 stress shadow is an issue of strong debate with important implications for earthquake mechanics and seismic hazards. Historically the SFBR has not experienced one complete earthquake cycle--the interval immediately following, then leading up to and repeating, a 1906-type (multi-segment rupture, M7.9) San Andreas event. The historical record of earthquake occurrence in the SFBR appears to be complete at about M5.5 back to 1850 (Bakun, 1999), which is less than half a cycle. For large events (qualitatively placed at M*7) Toppozada and Borchardt (1998) suggest the record is complete back to 1776, which may represent about half a cycle. During this period only the southern Hayward fault (1868) and the San Andreas fault (1838?, 1906) have produced their expected large events. New paleoseismic data now provide, for the first time, a more complete view of the most recent pre-1906 SFBR earthquake cycle. Focused paleoseismic efforts under the Bay Area Paleoearthquake Experiment (BAPEX) have developed a chronology of the most recent large earthquakes (MRE) on major SFBR faults. The San Andreas (SA), northern Hayward (NH), southern Hayward (SH), Rodgers Creek (RC), and northern Calaveras (NC) faults provide clear paleoseismic evidence for large events post-1600 AD. The San Gregorio (SG) may have also produced a large earthquake after this date. The timing of the MREs, in years AD, follows. The age ranges are 2-sigma radiocarbon intervals; the dates in parentheses are 1-sigma. MRE ages are: a) SA 1600-1670 (1630-1660), NH 1640-1776 (1635-1776); SH 1635-1776 (1685-1676); RC 1670-1776 (1730-1776); NC 1670-1830?; and San Gregorio 1270-1776 but possibly 1640-1776 (1685-1776). Based on present radiocarbon dating, the NH

  10. Earthquake supersite project in the Messina Straits area (EQUAMES)

    NASA Astrophysics Data System (ADS)

    Mattia, Mario; Chiarabba, Claudio; Dell'Acqua, Fabio; Faccenna, Claudio; Lanari, Riccardo; Matteuzzi, Francesco; Neri, Giancarlo; Patanè, Domenico; Polonia, Alina; Prati, Claudio; Tinti, Stefano; Zerbini, Susanna

    2015-04-01

    A new permanent supersite is going to be proposed to the GEO GSNL (Geohazard Supersites and National Laboratories) for the Messina Straits area (Italy). The justification for this new supersite can be found in its geological and geophysical features and in the exposure to strong earthquakes, also in the recent past (1908). The Messina Supersite infrastructure (EQUAMES: EarthQUAkes in the MEssina Straits) will host, and contribute to the collection of, large amounts of data, basic for the analysis of seismic hazard/risk in this high seismic risk area, including risk from earthquake-related processes such as submarine mass failures and tsunamis. In EQUAMES, data of different types will coexist with models and methods useful for their analysis/interpretation and with first-level products of analysis that can be of interest for different kinds of users. EQUAMES will help all the interested scientific and non-scientific subjects to find and use data and to increase inter-institutional cooperation by addressing the following main topics in the Messina Straits area: • investigation of the geological and physical processes leading to the earthquake preparation and generation; • analysis of seismic shaking at ground (expected and observed); • combination of seismic hazard with vulnerability and exposure data for risk estimates; • analysis of tsunami generation, propagation and coastal inundation deriving from earthquake occurrence also through landslides due to instability conditions of subaerial and submarine slopes; • overall risk associated to earthquake activity in the Supersite area including the different types of cascade effects Many Italian and international Institutions have shown an effective interest in this project where a large variety of geophysical and geological in-situ data will be collected and where the INGV has the leading role with its large infrastructure of seismic, GPS and geochemical permanent stations. The groups supporting EQUAMES

  11. Role of community health nurse in earthquake affected areas.

    PubMed

    Gulzar, Saleema Aziz; Faheem, Zahid Ali; Somani, Rozina Karim

    2012-10-01

    The role of Community Health Nurses (CHNs) outside the traditional hospital setting is meant to provide and promote the health care needs of the community. Such nurses can play a substantial role in the community setting including emergencies like disasters. This became evident after the earthquake of October 8, 2005 in Pakistan. The objective was to address the issues, faced by primary healthcare providers working in earthquake-affected areas focusing on participatory approach. The experience of the interventions done by CHN by a guided frame work (assessment, planning, implementation and evaluation components) is described. Issues identified by CHN included: lack of training of health care providers, lack of collaboration, communication between the medical and management staff due to poor infrastructure of the healthcare facilities. The interventions were carried out, utilizing existing resources. Efforts were directed to build capacity of health care providers at grass root level to fill in gaps of health care delivery system for sustainable change. Overall, working in the earthquake affected areas is challenging. Health leadership should foresee role of CHN in emergencies where quality healthcare interventions are essential.

  12. Earthquakes.

    ERIC Educational Resources Information Center

    Walter, Edward J.

    1977-01-01

    Presents an analysis of the causes of earthquakes. Topics discussed include (1) geological and seismological factors that determine the effect of a particular earthquake on a given structure; (2) description of some large earthquakes such as the San Francisco quake; and (3) prediction of earthquakes. (HM)

  13. Earthquakes

    ERIC Educational Resources Information Center

    Roper, Paul J.; Roper, Jere Gerard

    1974-01-01

    Describes the causes and effects of earthquakes, defines the meaning of magnitude (measured on the Richter Magnitude Scale) and intensity (measured on a modified Mercalli Intensity Scale) and discusses earthquake prediction and control. (JR)

  14. In vivo roles of BamA, BamB and BamD in the biogenesis of BamA, a core protein of the β-barrel assembly machine of Escherichia coli.

    PubMed

    Misra, Rajeev; Stikeleather, Ryan; Gabriele, Rebecca

    2015-03-13

    Assembly of the β-barrel outer membrane proteins (OMPs) is an essential cellular process in Gram-negative bacteria and in the mitochondria and chloroplasts of eukaryotes--two organelles of bacterial origin. Central to this process is the conserved β-barrel OMP that belongs to the Omp85 superfamily. In Escherichia coli, BamA is the core β-barrel OMP and, together with four outer membrane lipoproteins, BamBCDE, constitutes the β-barrel assembly machine (BAM). In this paper, we investigated the roles of BamD, an essential lipoprotein, and BamB in BamA biogenesis. Depletion of BamD caused impairment in BamA biogenesis and cessation of cell growth. These defects of BamD depletion were partly reversed by single-amino-acid substitutions mapping within the β-barrel domain of BamA. However, in the absence of BamB, the positive effects of the β-barrel substitutions on BamA biogenesis under BamD depletion conditions were nullified. By employing a BamA protein bearing one such substitution, F474L, it was demonstrated that the mutant BamA protein could not only assemble without BamD but also facilitate the assembly of wild-type BamA expressed in trans. Based on these data, we propose a model in which the Bam lipoproteins, which are localized to the outer membrane by the BAM-independent Lol pathway, aid in the creation of new BAM complexes by serving as outer membrane receptors and folding factors for nascent BamA molecules. The newly assembled BAM holocomplex then catalyzes the assembly of substrate OMPs and BamA. These in vivo findings are corroborated by recently published in vitro data. PMID:24792419

  15. New fault picture points toward San Francisco Bay area earthquakes

    SciTech Connect

    Kerr, R.A.

    1989-01-01

    Recent earthquakes along the Calaveras fault in California appear to form a pattern of northward movement along the fault, indicating the possibility of earthquake prediction. Three researchers have analyzed historic microearthquake data for this fault. The paper describes their findings and explains their prediction of a 5.5 magnitude or larger earthquake along a 4-kilometer section of the fault near its northern end.

  16. Archaeoseismological Study of Prehistoric Earthquakes in Anhui Province, China and Adjacent Areas

    NASA Astrophysics Data System (ADS)

    Yao, D.; Shen, X.; Gong, X.; Wu, W.; Hu, Z.; Zheng, H.; Chen, A.; Zhao, P.; Yang, Y.

    2014-12-01

    Damaging earthquakes on faults typically recur at intervals of centuries to millennia but the seismographs that record them have only been around for about hundred years. Complete records of earthquakes of Ms5 or above for Anhui Province of China and its adjacent areas began in 1336 and most previous records were lost. To reduce the hazard from earthquakes we need a longer record of them than can be provided from such instruments. Archaeoseismological evidence has the potential to determine earthquake activity over millennial time spans, especially when integrated with historical documents and geological evidence. In recent years, taking advantage of large-scale civil excavations, our research team including earthquake and archaeological scientists have cataloged, identified, and analyzed deformation relics of the late-Quaternary period, especially the Neolithic Age. Prehistoric earthquake traces were found in the cultural layers of the Western Zhou Dynasty and the Spring and Autumn Period in Southwest Anhui, the late Dawenkou cultural period in North Anhui, and the Eastern Zhou in South Henan. Along the segment of the Tanlu Fault Zone on the border of Jiangsu-Anhui Provinces, several rapid deformation events mainly in the form of oblique translational thrust had occurred since Late Pleistocene, which was confirmed by microscopic studies. The research findings have partly filled the gap of earthquake records in the area and enriched research methodologies in archaeology, prehistoric earthquakes and earthquake prediction. The project was sponsored by China Earthquake Science Special Research Funding Program (#201308012)

  17. Analysis of rupture area of aftershocks caused by twin earthquakes (Case study: 11 April 2012 earthquakes of Aceh-North Sumatra)

    SciTech Connect

    Diansari, Angga Vertika Purwana, Ibnu; Subakti, Hendri

    2015-04-24

    The 11 April 2012 earthquakes off-shore Aceh-North Sumatra are unique events for the history of Indonesian earthquake. It is unique because that they have similar magnitude, 8.5 Mw and 8.1 Mw; close to epicenter distance, similar strike-slip focal mechanism, and occuring in outer rise area. The purposes of this research are: (1) comparing area of earthquakes base on models and that of calculation, (2) fitting the shape and the area of earthquake rupture zones, (3) analyzing the relationship between rupture area and magnitude of the earthquakes. Rupture area of the earthquake fault are determined by using 4 different formulas, i.e. Utsu and Seki (1954), Wells and Coppersmith (1994), Ellsworth (2003), and Christophersen and Smith (2000). The earthquakes aftershock parameters are taken from PGN (PusatGempabumiNasional or National Earthquake Information Center) of BMKG (Indonesia Agency Meteorology Climatology and Geophysics). The aftershock epicenters are plotted by GMT’s software. After that, ellipse and rectangular models of aftershock spreading are made. The results show that: (1) rupture areas were calculated using magnitude relationship which are larger than the the aftershock distributions model, (2) the best fitting model for that earthquake aftershock distribution is rectangular associated with Utsu and Seki (1954) formula, (3) the larger the magnitude of the earthquake, the larger area of the fault.

  18. Evansville Area Earthquake Hazards Mapping Project (EAEHMP) - Progress Report, 2008

    USGS Publications Warehouse

    Boyd, Oliver S.; Haase, Jennifer L.; Moore, David W.

    2009-01-01

    Maps of surficial geology, deterministic and probabilistic seismic hazard, and liquefaction potential index have been prepared by various members of the Evansville Area Earthquake Hazard Mapping Project for seven quadrangles in the Evansville, Indiana, and Henderson, Kentucky, metropolitan areas. The surficial geologic maps feature 23 types of surficial geologic deposits, artificial fill, and undifferentiated bedrock outcrop and include alluvial and lake deposits of the Ohio River valley. Probabilistic and deterministic seismic hazard and liquefaction hazard mapping is made possible by drawing on a wealth of information including surficial geologic maps, water well logs, and in-situ testing profiles using the cone penetration test, standard penetration test, down-hole shear wave velocity tests, and seismic refraction tests. These data were compiled and collected with contributions from the Indiana Geological Survey, Kentucky Geological Survey, Illinois State Geological Survey, United States Geological Survey, and Purdue University. Hazard map products are in progress and are expected to be completed by the end of 2009, with a public roll out in early 2010. Preliminary results suggest that there is a 2 percent probability that peak ground accelerations of about 0.3 g will be exceeded in much of the study area within 50 years, which is similar to the 2002 USGS National Seismic Hazard Maps for a firm rock site value. Accelerations as high as 0.4-0.5 g may be exceeded along the edge of the Ohio River basin. Most of the region outside of the river basin has a low liquefaction potential index (LPI), where the probability that LPI is greater than 5 (that is, there is a high potential for liquefaction) for a M7.7 New Madrid type event is only 20-30 percent. Within the river basin, most of the region has high LPI, where the probability that LPI is greater than 5 for a New Madrid type event is 80-100 percent.

  19. Prevalence of HCV and HIV infections in 2005-Earthquake-affected areas of Pakistan

    PubMed Central

    Khan, Saeed; Rai, Mohammad A; Khan, Adnan; Farooqui, Amber; Kazmi, Shahana U; Ali, Syed H

    2008-01-01

    Background On October 8, 2005, an earthquake of magnitude 7.6 hit the Northern parts of Pakistan. In the post-earthquake scenario, overcrowding, improper sewage disposal, contamination of food and drinking water, hasty surgical procedures, and unscreened blood transfusions to earthquake victims most likely promotes the spread of infections already prevalent in the area. Objective The objective of the study reported here was to determine the prevalence of Human Immunodeficiency and Hepatitis C viruses (respectively, HIV and HCV) in the earthquake-affected communities of Pakistan. The samples were analyzed 2 months and then again 11 months after the earthquake to estimate the burden of HIV and HCV in these areas, and to determine any rise in the prevalence of these viral infections as a result of the earthquake. Methods Blood samples were initially collected during December, 2005 to March 2006, from 245 inhabitants of the earthquake-affected areas. These samples were screened for HCV and HIV, using immunochromatography and Enzyme-Linked Immuno-Sorbent Assay (ELISA). Results Out of 245 samples tested, 8 (3.26%) were found positive for HCV, and 0 (0.0%) for HIV, indicating the existence of HCV infection in the earthquake-stricken areas. The same methods were used to analyze the samples collected in the second round of screening in the same area, in September, 2006 – 11 months after the earthquake. This time 290 blood samples were collected, out of which 16 (5.51%) samples were positive for HCV, and 0 for HIV. Conclusion A slightly higher prevalence of HCV was recorded 11 months after the earthquake; this increase, however, was not statistically significant. None of the study participants was found HIV-infected. PMID:18954443

  20. Identification of Earthquake Induced Damage Areas Using Fourier Transform and SPOT HRVIR Pan Images.

    PubMed

    Sertel, Elif

    2009-01-01

    A devastating earthquake with a magnitude of Mw 7.4 occurred on the North Anatolian Fault Zone (NAFZ) of Turkey on August 17, 1999 at 00:01:39 UTC (3:01 a.m. local time). The aim of this study is to propose a new approach to automatically identify earthquake induced damage areas which can provide valuable information to support emergency response and recovery assessment procedures. This research was conducted in the Adapazari inner city, covering a 3 × 3 km area, where 11,373 buildings collapsed as a result of the earthquake. SPOT high resolution visible infrared (HRVIR) Pan images obtained before (25 June 1999) and after (4 October 1999) the earthquake were used in the study. Five steps were employed to conduct the research and these are: (i) geometric and radiometric correction of satellite images, (ii) Fast Fourier Transform (FFT) of pre- and post-earthquake images and filtering the images in frequency domain, (iii) generating difference image using Inverse Fast Fourier Transform (IFFT) pre- and post- earthquake images, (iv) application of level slicing to difference image to identify the earthquake-induced damages, (v) accuracy assessment of the method using ground truth obtained from a 1/5,000 scale damage map. The total accuracy obtained in the research is 80.19 %, illustrating that the proposed method can be successfully used to automatically identify earthquake-induced damage areas.

  1. Identification of Earthquake Induced Damage Areas Using Fourier Transform and SPOT HRVIR Pan Images

    PubMed Central

    Sertel, Elif

    2009-01-01

    A devastating earthquake with a magnitude of Mw 7.4 occurred on the North Anatolian Fault Zone (NAFZ) of Turkey on August 17, 1999 at 00:01:39 UTC (3:01 a.m. local time). The aim of this study is to propose a new approach to automatically identify earthquake induced damage areas which can provide valuable information to support emergency response and recovery assessment procedures. This research was conducted in the Adapazari inner city, covering a 3 × 3 km area, where 11,373 buildings collapsed as a result of the earthquake. SPOT high resolution visible infrared (HRVIR) Pan images obtained before (25 June 1999) and after (4 October 1999) the earthquake were used in the study. Five steps were employed to conduct the research and these are: (i) geometric and radiometric correction of satellite images, (ii) Fast Fourier Transform (FFT) of pre- and post-earthquake images and filtering the images in frequency domain, (iii) generating difference image using Inverse Fast Fourier Transform (IFFT) pre- and post- earthquake images, (iv) application of level slicing to difference image to identify the earthquake-induced damages, (v) accuracy assessment of the method using ground truth obtained from a 1/5,000 scale damage map. The total accuracy obtained in the research is 80.19 %, illustrating that the proposed method can be successfully used to automatically identify earthquake-induced damage areas. PMID:22573966

  2. Earthquake!

    ERIC Educational Resources Information Center

    Hernandez, Hildo

    2000-01-01

    Examines the types of damage experienced by California State University at Northridge during the 1994 earthquake and what lessons were learned in handling this emergency are discussed. The problem of loose asbestos is addressed. (GR)

  3. Spatial Distribution of earthquakes off the coast of Fukushima Two Years after the M9 Earthquake: the Southern Area of the 2011 Tohoku Earthquake Rupture Zone

    NASA Astrophysics Data System (ADS)

    Yamada, T.; Nakahigashi, K.; Shinohara, M.; Mochizuki, K.; Shiobara, H.

    2014-12-01

    Huge earthquakes cause vastly stress field change around the rupture zones, and many aftershocks and other related geophysical phenomenon such as geodetic movements have been observed. It is important to figure out the time-spacious distribution during the relaxation process for understanding the giant earthquake cycle. In this study, we pick up the southern rupture area of the 2011 Tohoku earthquake (M9.0). The seismicity rate keeps still high compared with that before the 2011 earthquake. Many studies using ocean bottom seismometers (OBSs) have been doing since soon after the 2011 Tohoku earthquake in order to obtain aftershock activity precisely. Here we show one of the studies at off the coast of Fukushima which is located on the southern part of the rupture area caused by the 2011 Tohoku earthquake. We deployed 4 broadband type OBSs (BBOBSs) and 12 short-period type OBSs (SOBS) in August 2012. Other 4 BBOBSs attached with absolute pressure gauges and 20 SOBSs were added in November 2012. We recovered 36 OBSs including 8 BBOBSs in November 2013. We selected 1,000 events in the vicinity of the OBS network based on a hypocenter catalog published by the Japan Meteorological Agency, and extracted the data after time corrections caused by each internal clock. Each P and S wave arrival times, P wave polarity and maximum amplitude were picked manually on a computer display. We assumed one dimensional velocity structure based on the result from an active source experiment across our network, and applied time corrections every station for removing ambiguity of the assumed structure. Then we adopted a maximum-likelihood estimation technique and calculated the hypocenters. The results show that intensive activity near the Japan Trench can be seen, while there was a quiet seismic zone between the trench zone and landward high activity zone.

  4. Earthquake Rate Model 2 of the 2007 Working Group for California Earthquake Probabilities, Magnitude-Area Relationships

    USGS Publications Warehouse

    Stein, Ross S.

    2008-01-01

    The Working Group for California Earthquake Probabilities must transform fault lengths and their slip rates into earthquake 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 Earthquake 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 earthquakes. 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 earthquake slip. We have not opted to use the alternative relation for the current model. The selections and weights were developed by unanimous consensus of the Executive Committee of the Working Group, following an open meeting of scientists, a solicitation of outside opinions from additional scientists, and presentation of our approach to the Scientific Review Panel. The magnitude-area relations and their assigned weights are unchanged from that used in Working Group (2003).

  5. Detection of Interplate Earthquakes in the Source Area of the 2011 Tohoku Earthquake Using Extensive Seafloor Aftershock Observation Data

    NASA Astrophysics Data System (ADS)

    Nakatani, Y.; Mochizuki, K.; Shinohara, M.; Yamada, T.; Shiobara, H.; Hino, R.; Azuma, R.; Ito, Y.; Murai, Y.; Sato, T.; Uehira, K.; Shimbo, T.; Yakiwara, H.; Kodaira, S.; Machida, Y.; Hirata, K.; Tsushima, H.

    2015-12-01

    Previous studies on the source process of the 2011 Mw 9.0 Tohoku earthquake have revealed its large coseismic slip along a shallow plate interface to the Japan Trench axis. In order to further understand the complex rupture propagation along the plate interface, it is essential to elucidate recovery process of interplate coupling in the source area after the Tohoku earthquake. Estimating changes in b-values for interplate earthquakes before and after the Tohoku event is one of the available approaches to answer the above issue. To start with, we attempt to automatically detect and determine the location of interplate earthquakes using extensive seafloor aftershock observation data. We used mainly short-period pop-up type ocean bottom seismometers (OBSs) [Shinohara et al., 2011, 2012]. We applied a semblance-based method [Nakatani et al., 2015] to 23 OBSs deployed off Fukushima. A seismic tomography result [Matsubara and Obara, 2011] is used for calculation of P wave traveltimes between OBS stations and given grids along the plate interface. To confirm the validity of our method, we conducted synthetic tests by using a Ricker wavelet with several different sets of signal-to-noise (S/N) ratio and focal depths. As the results, semblance values of earthquakes with focal depths relative to the plate interface of 5 km are comparable to noise level, regardless of S/N ratio. On the other hand, earthquakes along the plate interface have significant peak semblance values. Therefore, our method is effective for detection of interplate earthquakes. We, then, applied the method to several waveforms of interplate events listed in the JMA (Japan Meteorological Agency) catalog and identified epicenters by backprojecting semblance values. We compared our resulted epicenters to those of Shinohara et al. (2011, 2012) which precisely relocated the JMA ones using P- and S-wave arrival times and maximum-likelihood estimate technique. The results show good coincidence between them. In

  6. Earthquake prediction in seismogenic areas of the Iberian Peninsula based on computational intelligence

    NASA Astrophysics Data System (ADS)

    Morales-Esteban, A.; Martínez-Álvarez, F.; Reyes, J.

    2013-05-01

    A method to predict earthquakes in two of the seismogenic areas of the Iberian Peninsula, based on Artificial Neural Networks (ANNs), is presented in this paper. ANNs have been widely used in many fields but only very few and very recent studies have been conducted on earthquake prediction. Two kinds of predictions are provided in this study: a) the probability of an earthquake, of magnitude equal or larger than a preset threshold magnitude, within the next 7 days, to happen; b) the probability of an earthquake of a limited magnitude interval to happen, during the next 7 days. First, the physical fundamentals related to earthquake occurrence are explained. Second, the mathematical model underlying ANNs is explained and the configuration chosen is justified. Then, the ANNs have been trained in both areas: The Alborán Sea and the Western Azores-Gibraltar fault. Later, the ANNs have been tested in both areas for a period of time immediately subsequent to the training period. Statistical tests are provided showing meaningful results. Finally, ANNs were compared to other well known classifiers showing quantitatively and qualitatively better results. The authors expect that the results obtained will encourage researchers to conduct further research on this topic. Development of a system capable of predicting earthquakes for the next seven days Application of ANN is particularly reliable to earthquake prediction. Use of geophysical information modeling the soil behavior as ANN's input data Successful analysis of one region with large seismic activity

  7. A parallel processing VLSI BAM engine.

    PubMed

    Hasan, S R; Siong, N K

    1997-01-01

    In this paper emerging parallel/distributed architectures are explored for the digital VLSI implementation of adaptive bidirectional associative memory (BAM) neural network. A single instruction stream many data stream (SIMD)-based parallel processing architecture, is developed for the adaptive BAM neural network, taking advantage of the inherent parallelism in BAM. This novel neural processor architecture is named the sliding feeder BAM array processor (SLiFBAM). The SLiFBAM processor can be viewed as a two-stroke neural processing engine, It has four operating modes: learn pattern, evaluate pattern, read weight, and write weight. Design of a SLiFBAM VLSI processor chip is also described. By using 2-mum scalable CMOS technology, a SLiFBAM processor chip with 4+4 neurons and eight modules of 256x5 bit local weight-storage SRAM, was integrated on a 6.9x7.4 mm(2) prototype die. The system architecture is highly flexible and modular, enabling the construction of larger BAM networks of up to 252 neurons using multiple SLiFBAM chips.

  8. Frequency spectrum method-based stress analysis for oil pipelines in earthquake disaster areas.

    PubMed

    Wu, Xiaonan; Lu, Hongfang; Huang, Kun; Wu, Shijuan; Qiao, Weibiao

    2015-01-01

    When a long distance oil pipeline crosses an earthquake disaster area, inertial force and strong ground motion can cause the pipeline stress to exceed the failure limit, resulting in bending and deformation failure. To date, researchers have performed limited safety analyses of oil pipelines in earthquake disaster areas that include stress analysis. Therefore, using the spectrum method and theory of one-dimensional beam units, CAESAR II is used to perform a dynamic earthquake analysis for an oil pipeline in the XX earthquake disaster area. This software is used to determine if the displacement and stress of the pipeline meet the standards when subjected to a strong earthquake. After performing the numerical analysis, the primary seismic action axial, longitudinal and horizontal displacement directions and the critical section of the pipeline can be located. Feasible project enhancement suggestions based on the analysis results are proposed. The designer is able to utilize this stress analysis method to perform an ultimate design for an oil pipeline in earthquake disaster areas; therefore, improving the safe operation of the pipeline.

  9. Frequency Spectrum Method-Based Stress Analysis for Oil Pipelines in Earthquake Disaster Areas

    PubMed Central

    Wu, Xiaonan; Lu, Hongfang; Huang, Kun; Wu, Shijuan; Qiao, Weibiao

    2015-01-01

    When a long distance oil pipeline crosses an earthquake disaster area, inertial force and strong ground motion can cause the pipeline stress to exceed the failure limit, resulting in bending and deformation failure. To date, researchers have performed limited safety analyses of oil pipelines in earthquake disaster areas that include stress analysis. Therefore, using the spectrum method and theory of one-dimensional beam units, CAESAR II is used to perform a dynamic earthquake analysis for an oil pipeline in the XX earthquake disaster area. This software is used to determine if the displacement and stress of the pipeline meet the standards when subjected to a strong earthquake. After performing the numerical analysis, the primary seismic action axial, longitudinal and horizontal displacement directions and the critical section of the pipeline can be located. Feasible project enhancement suggestions based on the analysis results are proposed. The designer is able to utilize this stress analysis method to perform an ultimate design for an oil pipeline in earthquake disaster areas; therefore, improving the safe operation of the pipeline. PMID:25692790

  10. Scenario earthquake hazards for the Long Valley Caldera-Mono Lake area, east-central California

    USGS Publications Warehouse

    Chen, Rui; Branum, David M.; Wills, Chris J.; Hill, David P.

    2014-01-01

    As part of the U.S. Geological Survey’s (USGS) multi-hazards project in the Long Valley Caldera-Mono Lake area, the California Geological Survey (CGS) developed several earthquake scenarios and evaluated potential seismic hazards, including ground shaking, surface fault rupture, liquefaction, and landslide hazards associated with these earthquake scenarios. The results of these analyses can be useful in estimating the extent of potential damage and economic losses because of potential earthquakes and in preparing emergency response plans. The Long Valley Caldera-Mono Lake area has numerous active faults. Five of these faults or fault zones are considered capable of producing magnitude ≥6.7 earthquakes according to the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2) developed by the 2007 Working Group of California Earthquake Probabilities (WGCEP) and the USGS National Seismic Hazard Mapping (NSHM) Program. These five faults are the Fish Slough, Hartley Springs, Hilton Creek, Mono Lake, and Round Valley Faults. CGS developed earthquake scenarios for these five faults in the study area and for the White Mountains Fault to the east of the study area. Earthquake scenarios are intended to depict the potential consequences of significant earthquakes. They are not necessarily the largest or most damaging earthquakes possible. Earthquake scenarios are both large enough and likely enough that emergency planners should consider them in regional emergency response plans. Earthquake scenarios presented here are based on fault geometry and activity data developed by the WGCEP, and are consistent with the 2008 Update of the United States National Seismic Hazard Maps (NSHM).For the Hilton Creek Fault, two alternative scenarios were developed in addition to the NSHM scenario to account for different opinions in how far north the fault extends into the Long Valley Caldera. For each scenario, ground motions were calculated using the current standard practice

  11. Long Term Analysis for the BAM device

    NASA Astrophysics Data System (ADS)

    Bonino, D.; Gardiol, D.

    2011-02-01

    Algorithms aimed at the evaluation of critical quantities are based on models with many parameters, which values are estimated from data. The knowledge, with high accuracy, of these values and the control of their temporal evolution are important features. In this work, we focus on the latter subject, and we show a proposed pipeline for the BAM (Basic Angle Monitoring) Long Term Analysis, aimed at the study of the calibration parameters of the BAM device and of the Basic Angle variation, searching for unwanted trends, cyclic features, or other potential unexpected behaviours.

  12. Study on Features of Secondary Disasters in the Worst-hit Areas of Wenchuan Earthquake

    NASA Astrophysics Data System (ADS)

    Liu, S.; Guo, W.

    2008-12-01

    The Wenchuan earthquake on May 12, 2008 has caused heavy casualties and property losses. The violent earthquake and numerous intense aftershocks also induced secondary natural disasters in large area, which seriously threaten the regional eco-environment and human settlement environment. Based on the field investigation of some disaster area and analysis on RS data collected after the earthquake, the authors present the following opinions on features of secondary disaster caused by the Wenchuan earthquake. The Wenchuan earthquake occurred at the Longmen Mountain fault zone, which starts from east side of the Jiajin Mountain in Tianquan, Ya'an, and extends northeastward connecting with the Daba Mountain fault zone, approximately 500 km long and 70 km wide. This fault zone is composed of the front mountain the fault, central fracture and the rear mountain fault. Primary disaster area is mostly in the central fault zone. Large geomorphological unit of the disaster area is located at the transitional zone between the upmost ladder and middle ladder of landform in China. Primary disaster area is in the high mountain and middle mountain areas at edge of the Sichuan Basin, where valleys are deeply incised by streams and the mountains are very high with very steep slopes, greater than 25 degrees at most sites. The worst-hit area is of subtropical mountainous humid region under monsoon climate. Tendency of the mountain range is in a northeast-southwest orientation, so it is windward to southwestern monsoon, and has plenteous precipitation. Annual precipitation in Dujiangyan is 1178mm, and 1280mm in Beichuan, which are the center of opulent rainfall region in China. It provides conditions for incompact materials to form debris flow after the earthquake. The strong earthquake altered the landscape in disaster area violently. Under the action of seismic force and gravity, a great quantity of materials loosened in the earthquake slide downwards along steep slopes, thus

  13. Moderate, strong and strongest earthquake-prone areas in the Caucasus, California and the Andes

    NASA Astrophysics Data System (ADS)

    Dzeboev, Boris; Gvishiani, Alexei

    2016-04-01

    We present this study on recognition of areas of possible occurrence of strong earthquakes. The study deals with the earthquake-prone areas in three regions with different geological and tectonic structures located in different parts of the world. The authors created a new method (FCAZ - Fuzzy Clustering and Zoning) for recognition of highly seismic areas, where epicenters of earthquakes with magnitude M≥M0 can occur. The magnitude threshold M0 depends on the seismic activity of the region. The objects of clustering are earthquake epicenters. The new method allows us to implement uniformly necessary clustering of the recognition objects respectively for moderate, strong and strongest events. Suggested approach consists of two steps: clustering of known earthquake epicenters by the original DPS (Discrete Perfect Sets) algorithm and delineating highly seismic zones around the recognized clusters by another original E2XT algorithm. By means of this method we detected the areas of possible occurrence of the epicenters of strong earthquakes in the Caucasus (M≥5), in California (M≥6.5) and in the mountain belt of the Andes (M≥7.75). The latter case relates to the possible areas of natural disaster occurence. Reliability of the results is confirmed by numerous control experiments, including individual and complete seismic history. Two strongest recent Chilean earthquakes occurred in 2014 and 2015 after the moment the results were published. Their epicenters belong to the zone recognized as high seismically hazardous. It is a strong independent argument which confirms the reliability of the results. The presented results integrate most recent outcomes of more than 40 years of research in pattern recognition and systems analysis for seismic zoning implemented in Russian Academy of Science. This research is supported by the Russian Science Foundation (project № 15-17-30020).

  14. Long-period building response to earthquakes in the San Francisco Bay Area

    USGS Publications Warehouse

    Olsen, A.H.; Aagaard, B.T.; Heaton, T.H.

    2008-01-01

    This article reports a study of modeled, long-period building responses to ground-motion simulations of earthquakes in the San Francisco Bay Area. The earthquakes include the 1989 magnitude 6.9 Loma Prieta earthquake, a magnitude 7.8 simulation of the 1906 San Francisco earthquake, and two hypothetical magnitude 7.8 northern San Andreas fault earthquakes with hypocenters north and south of San Francisco. We use the simulated ground motions to excite nonlinear models of 20-story, steel, welded moment-resisting frame (MRF) buildings. We consider MRF buildings designed with two different strengths and modeled with either ductile or brittle welds. Using peak interstory drift ratio (IDR) as a performance measure, the stiffer, higher strength building models outperform the equivalent more flexible, lower strength designs. The hypothetical magnitude 7.8 earthquake with hypocenter north of San Francisco produces the most severe ground motions. In this simulation, the responses of the more flexible, lower strength building model with brittle welds exceed an IDR of 2.5% (that is, threaten life safety) on 54% of the urban area, compared to 4.6% of the urban area for the stiffer, higher strength building with ductile welds. We also use the simulated ground motions to predict the maximum isolator displacement of base-isolated buildings with linear, single-degree-of-freedom (SDOF) models. For two existing 3-sec isolator systems near San Francisco, the design maximum displacement is 0.5 m, and our simulations predict isolator displacements for this type of system in excess of 0.5 m in many urban areas. This article demonstrates that a large, 1906-like earthquake could cause significant damage to long-period buildings in the San Francisco Bay Area.

  15. Detecting earthquake damage in urban area: application to COSMO-SkyMed imagery of L'Aquila earthquake

    NASA Astrophysics Data System (ADS)

    Anniballe, R.; Chini, M.; Pierdicca, N.; Bignami, C.; Stramondo, S.; Noto, F.; Scalia, T.; Martinelli, A.; Mannella, A.

    2015-10-01

    Due to the improved spatial resolution, Earth observation (EO) data, either from Synthetic Aperture Radar (SAR) or optical sensor, provide the opportunity to assess earthquake damage of individual buildings. However, the operational use of EO data for earthquake damage mapping is basically limited to the visual inspection of Very High Resolution (VHR) optical imagery. In this work we investigate the feasibility of a damage assessment product at single building scale from a pair of VHR SAR images acquired before and after a seismic event. We perform the change analysis using the Kullbach-Leibler divergence and the intensity ratio and then we associate detected changes to a building map provided as GIS layer. Finally the expected SAR signature of a collapsed building is considered to identify severely damaged buildings. In order to test the proposed methodology we use Spotlight COSMO-SkyMed SAR imagery of L'Aquila (Italy) collected before and after the earthquake occurred on April 6, 2009. A macroseismic survey on the whole central area of L'Aquila city based on the European Macroseismic Scale 1998 is used to assess the capability of VHR SAR images to map damage.

  16. Mega-thrust and Intra-slab Earthquakes Beneath Tokyo Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Sato, H.; Koketsu, K.; Hagiwara, H.; Wu, F.; Okaya, D.; Iwasaki, T.; Kasahara, K.

    2006-12-01

    In central Japan the Philippine Sea plate (PSP) subducts beneath the Tokyo Metropolitan area, the Kanto region, where it causes mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9) which had 105,000 fatalities. The vertical proximity of this down going lithospheric plate is of concern because the greater Tokyo urban region has a population of 42 million and is the center of approximately 40% of the nation's economic activities. A M7+ earthquake in this region at present has high potential to produce devastating loss of life and property with even greater global economic repercussions. The M7+ earthquake is evaluated to occur with a probability of 70% in 30 years by the Earthquake Research Committee of Japan. In 2002, a consortium of universities and government agencies in Japan started the Special Project for Earthquake Disaster Mitigation in Urban Areas, a project to improve information needed for seismic hazards analyses of the largest urban centers. Assessment in Kanto of the seismic hazard produced by the Philippine Sea Plate (PSP) mega-thrust earthquakes requires identification of all significant faults and possible earthquake scenarios and rupture behavior, regional characterizations of PSP geometry and the overlying Honshu arc physical properties (e.g., seismic wave velocities, densities, attenuation), and local near-surface seism ic site effects. Our study addresses (1) improved regional characterization of the PSP geometry based on new deep seismic reflection profiles (Sato etal.,2005), reprocessed off-shore profiles (Kimura et al.,2005), and a dense seismic array in the Boso peninsular (Hagiwara et al., 2006) and (2) identification of asperities of the mega-thrust at the top of the PSP. We qualitatively examine the relationship between seismic reflections and asperities inferred by reflection physical properties. We also discuss the relation between deformation of PSP and intra-slab M7+ earthquakes: the

  17. St. Louis Area Earthquake Hazards Mapping Project - A Progress Report-November 2008

    USGS Publications Warehouse

    Karadeniz, D.; Rogers, J.D.; Williams, R.A.; Cramer, C.H.; Bauer, R.A.; Hoffman, D.; Chung, J.; Hempen, G.L.; Steckel, P.H.; Boyd, O.L.; Watkins, C.M.; McCallister, N.S.; Schweig, E.

    2009-01-01

    St. Louis has experienced minor earthquake damage at least 12 times in the past 200 years. Because of this history and its proximity to known active earthquake zones, the St. Louis Area Earthquake Hazards Mapping Project (SLAEHMP) is producing digital maps that show variability of earthquake hazards, including liquefaction and ground shaking, in the St. Louis area. The maps will be available free via the internet. Although not site specific enough to indicate the hazard at a house-by-house resolution, they can be customized by the user to show specific areas of interest, such as neighborhoods or transportation routes. Earthquakes currently cannot be predicted, but scientists can estimate how strongly the ground is likely to shake as the result of an earthquake. Earthquake hazard maps provide one way of conveying such estimates. The U.S. Geological Survey (USGS), which produces earthquake hazard maps for the Nation, is working with local partners to develop detailed maps for urban areas vulnerable to strong ground shaking. These partners, which along with the USGS comprise the SLAEHMP, include the Missouri University of Science and Technology-Rolla (Missouri S&T), Missouri Department of Natural Resources (MDNR), Illinois State Geological Survey (ISGS), Saint Louis University, Missouri State Emergency Management Agency, and URS Corporation. Preliminary hazard maps covering a test portion of the 29-quadrangle St. Louis study area have been produced and are currently being evaluated by the SLAEHMP. A USGS Fact Sheet summarizing this project was produced and almost 1000 copies have been distributed at several public outreach meetings and field trips that have featured the SLAEHMP (Williams and others, 2007). In addition, a USGS website focusing on the SLAEHMP, which provides links to project results and relevant earthquake hazard information, can be found at: http://earthquake.usgs.gov/regional/ceus/urban_map/st_louis/index.php. This progress report summarizes the

  18. ABL and BAM Friction Analysis Comparison

    DOE PAGESBeta

    Warner, Kirstin F.; Sandstrom, Mary M.; Brown, Geoffrey W.; Remmers, Daniel L.; Phillips, Jason J.; Shelley, Timothy J.; Reyes, Jose A.; Hsu, Peter C.; Reynolds, John G.

    2014-12-29

    Here, the Integrated Data Collection Analysis (IDCA) program has conducted a proficiency study for Small-Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here is a comparison of the Alleghany Ballistic Laboratory (ABL) friction data and Bundesanstalt fur Materialforschung und -prufung (BAM) friction data for 19 HEM and military standard explosives.

  19. Chimney damage in the greater Seattle area from the Nisqually earthquake of 28 February 2001

    USGS Publications Warehouse

    Booth, D.B.; Wells, R.E.; Givler, R.W.

    2004-01-01

    Unreinforced brick chimneys in the greater Seattle area were damaged repeatedly in the Benioff zone earthquakes of 1949, 1965, and 2001. A survey of visible chimney damage after the 28 February 2001 Nisqually earthquake evaluated approximately 60,000 chimneys through block-by-block coverage of about 50 km2, identifying a total of 1556 damaged chimneys. Chimney damage was strongly clustered in certain areas, in particular in the neighborhood of West Seattle where prior damage was also noted and evaluated after the 1965 earthquake. Our results showed that damage produced by the 2001 earthquake did not obviously correspond to distance from the earthquake epicenter, soft soils, topography, or slope orientation. Chimney damage correlates well to instrumented strong-motion measurements and compiled resident-reported ground-shaking intensities, but it offers much finer spatial resolution than these other data sources. In general, most areas of greatest chimney damage coincide with best estimated locations of strands of the Seattle fault zone. The edge of that zone also coincides with areas where chimney damage dropped abruptly over only one or two blocks' distance. The association between shaking intensity and fault-zone structure suggests that abrupt changes in the depth to bedrock, edge effects at the margin of the Seattle basin, or localized trapping of seismic waves in the Seattle fault zone may be significant contributory factors in the distribution of chimney damage.

  20. Challenges for Resuming Normal Life After Earthquake: A Qualitative Study on Rural Areas of Iran

    PubMed Central

    Alipour, Fardin; Khankeh, Hamid Reza; Fekrazad, Hussain; Kamali, Mohammad; Rafiey, Hassan; Sarrami Foroushani, Pooria; Rowell, Kevin; Ahmadi, Shokoufeh

    2014-01-01

    Background and objective: Growing evidence is indicating that some of disaster affected people face challenges to resume normal life several months after an earthquake. However, there is no sufficient in-depth understanding of complex process of resuming normal life after an earthquake in Iran, as one of the most disaster-prone countries in the world, and in rural areas as a particular setting. This study aimed to explore challenges of return to normalcy in rural earthquake-stricken areas of Iran. Methods: The study was conducted using qualitative content analysis method (Graneheim approach). Twenty people from the earthquake-stricken areas and seven qualified experts were selected via purposeful sampling .Data was collected through semi-structured interviews, focus group discussions, and field notes from August 2013 to January 2014. Data collection continued to the point of data saturation (no new information was provided by interviewees). Data saturation supported the sample size. Data analysis was based on qualitative content analysis principles. Results: “Social uncertainty and confusion” was the most prominent challenge of return to the normal life after earthquake, which was categorized into six concepts of social vulnerability, lack of comprehensive rehabilitation plan, incomplete reconstruction, ignorance of local social capital, waste of assets, and psychological problems. Conclusions: Findings showed that social uncertainty and confusion occurs as a result of negligence of some important social aspects in process of returning to the normal life. This issue, in turn, can greatly interrupt the normal developmental processes. Understanding the challenges of life recovery after disasters will help policy makers consider social rehabilitation as a key factor in facilitation of return to normal life process after earthquakes. Keywords: Disaster; earthquake; social rehabilitation; social uncertainty. PMID:25685625

  1. Geomorphic effects of the earthquake of March 27, 1964, in the Martin-Bering Rivers area, Alaska: Chapter B in The Alaska earthquake, March 27, 1964: regional effects

    USGS Publications Warehouse

    Tuthill, Samuel J.; Laird, Wilson M.

    1966-01-01

    The Alaska earthquake of March 27, 1964, caused widespread geomorphic changes in the Martin-Bering Rivers area-900 square miles of uninhabited mountains, alluvial flatlands, and marshes north of the Gulf of Alaska, and east of the Copper River. This area is at lat 60°30’ N. and long 144°22’ W., 32 miles east of Cordova, and approximately 130 miles east-southeast of the epicenter of the earthquake. The geomorphic effects observed were: (1) earthquake-induced ground fractures, (2) mudvent deposits, (3) “earthquake-fountain” craters, (4) subsidence, (5) mudcones, (6) avalanches, (7) subaqueous landslides, (8) turbidity changes in ice-basined lakes on the Martin River glacier, (9) filling of ice-walled sinkholes, (10) gravel-coated snow cones, (11) lake ice fractures, and (12) uplift accompanied the earthquake. In addition to geomorphic effects, the earthquake affected the animal populations of the area. These include migratory fish, terrestrial mollusks, fur-bearing animals, and man. The Alaska earthquake clearly delineated areas of alluvial fill, snow and rock avalanche corridors, and deltas of the deeper lakes as unsuitable for future construction.

  2. A physically based expression for the total volume and area of earthquake induced landsliding.

    NASA Astrophysics Data System (ADS)

    Hovius, N.; Marc, O.; Meunier, P.; Gorum, T.; Uchida, T.

    2015-12-01

    Earthquake impart a catastrophic forcing on hillslopes, that often lead to widespread landsliding and can contribute significantly to sedimentary and organic matter fluxes. We present a new expression for the total area and volume of populations of earthquake-induced landslides.This model builds on a set of scaling relationships between key parameters, such as landslide density, ground acceleration, fault size, earthquake source depth and seismic moment, derived from geomorphological and seismological observations. To assess the model we have assembled and normalized a catalogue of landslide inventories for 40 earthquakes. We have found that low landscape steepness systematically leads to over-prediction of the total area and volume of landslides.When this effect is accounted for, the model is able to predict within a factor of 2 the landslide areas and associated volumes for about two thirds of the cases in our databases. This is a significant improvement on a previously published empirical expression based only on earthquake moment.The prediction of total area is also sensitive to the landscape steepness, but less than the total volume.It seems also affected by the controls on the landslide frequency distribution that may include ground strength, soil continuity and extent or antecedent moisture. Some outliers in terms of observed landslide intensity are likely to be associated with exceptionally rock strength in the epicentral area, while others may be related to seismic source complexities ignored by the model.However, most cases in our catalogue seem to be relatively unaffected by these two effects despite the variety of lithologies and tectonic settings they cover.This makes our expression suitable for integration into landscape evolution models, and application to the assessment of secondary hazards and risks associated with earthquakes.

  3. Multi-Parameter Observation and Detection of Pre-Earthquake Signals in Seismically Active Areas

    NASA Technical Reports Server (NTRS)

    Ouzounov, D.; Pulinets, S.; Parrot, M.; Liu, J. Y.; Hattori, K.; Kafatos, M.; Taylor, P.

    2012-01-01

    The recent large earthquakes (M9.0 Tohoku, 03/2011; M7.0 Haiti, 01/2010; M6.7 L Aquila, 04/2008; and M7.9 Wenchuan 05/2008) have renewed interest in pre-anomalous seismic signals associated with them. Recent workshops (DEMETER 2006, 2011 and VESTO 2009 ) have shown that there were precursory atmospheric /ionospheric signals observed in space prior to these events. Our initial results indicate that no single pre-earthquake observation (seismic, magnetic field, electric field, thermal infrared [TIR], or GPS/TEC) can provide a consistent and successful global scale early warning. This is most likely due to complexity and chaotic nature of earthquakes and the limitation in existing ground (temporal/spatial) and global satellite observations. In this study we analyze preseismic temporal and spatial variations (gas/radon counting rate, atmospheric temperature and humidity change, long-wave radiation transitions and ionospheric electron density/plasma variations) which we propose occur before the onset of major earthquakes:. We propose an Integrated Space -- Terrestrial Framework (ISTF), as a different approach for revealing pre-earthquake phenomena in seismically active areas. ISTF is a sensor web of a coordinated observation infrastructure employing multiple sensors that are distributed on one or more platforms; data from satellite sensors (Terra, Aqua, POES, DEMETER and others) and ground observations, e.g., Global Positioning System, Total Electron Content (GPS/TEC). As a theoretical guide we use the Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model to explain the generation of multiple earthquake precursors. Using our methodology, we evaluated retrospectively the signals preceding the most devastated earthquakes during 2005-2011. We observed a correlation between both atmospheric and ionospheric anomalies preceding most of these earthquakes. The second phase of our validation include systematic retrospective analysis for more than 100 major earthquakes (M>5

  4. Scenario earthquake hazards for the Long Valley Caldera-Mono Lake area, east-central California

    USGS Publications Warehouse

    Chen, Rui; Branum, David M.; Wills, Chris J.; Hill, David P.

    2014-01-01

    As part of the U.S. Geological Survey’s (USGS) multi-hazards project in the Long Valley Caldera-Mono Lake area, the California Geological Survey (CGS) developed several earthquake scenarios and evaluated potential seismic hazards, including ground shaking, surface fault rupture, liquefaction, and landslide hazards associated with these earthquake scenarios. The results of these analyses can be useful in estimating the extent of potential damage and economic losses because of potential earthquakes and in preparing emergency response plans. The Long Valley Caldera-Mono Lake area has numerous active faults. Five of these faults or fault zones are considered capable of producing magnitude ≥6.7 earthquakes according to the Uniform California Earthquake Rupture Forecast, Version 2 (UCERF 2) developed by the 2007 Working Group of California Earthquake Probabilities (WGCEP) and the USGS National Seismic Hazard Mapping (NSHM) Program. These five faults are the Fish Slough, Hartley Springs, Hilton Creek, Mono Lake, and Round Valley Faults. CGS developed earthquake scenarios for these five faults in the study area and for the White Mountains Fault to the east of the study area. Earthquake scenarios are intended to depict the potential consequences of significant earthquakes. They are not necessarily the largest or most damaging earthquakes possible. Earthquake scenarios are both large enough and likely enough that emergency planners should consider them in regional emergency response plans. Earthquake scenarios presented here are based on fault geometry and activity data developed by the WGCEP, and are consistent with the 2008 Update of the United States National Seismic Hazard Maps (NSHM).For the Hilton Creek Fault, two alternative scenarios were developed in addition to the NSHM scenario to account for different opinions in how far north the fault extends into the Long Valley Caldera. For each scenario, ground motions were calculated using the current standard practice

  5. Earthquakes Magnitude Predication Using Artificial Neural Network in Northern Red Sea Area

    NASA Astrophysics Data System (ADS)

    Alarifi, A. S.; Alarifi, N. S.

    2009-12-01

    Earthquakes are natural hazards that do not happen very often, however they may cause huge losses in life and property. Early preparation for these hazards is a key factor to reduce their damage and consequence. Since early ages, people tried to predicate earthquakes using simple observations such as strange or a typical animal behavior. In this paper, we study data collected from existing earthquake catalogue to give better forecasting for future earthquakes. The 16000 events cover a time span of 1970 to 2009, the magnitude range from greater than 0 to less than 7.2 while the depth range from greater than 0 to less than 100km. We propose a new artificial intelligent predication system based on artificial neural network, which can be used to predicate the magnitude of future earthquakes in northern Red Sea area including the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez. We propose a feed forward new neural network model with multi-hidden layers to predicate earthquakes occurrences and magnitudes in northern Red Sea area. Although there are similar model that have been published before in different areas, to our best knowledge this is the first neural network model to predicate earthquake in northern Red Sea area. Furthermore, we present other forecasting methods such as moving average over different interval, normally distributed random predicator, and uniformly distributed random predicator. In addition, we present different statistical methods and data fitting such as linear, quadratic, and cubic regression. We present a details performance analyses of the proposed methods for different evaluation metrics. The results show that neural network model provides higher forecast accuracy than other proposed methods. The results show that neural network achieves an average absolute error of 2.6% while an average absolute error of 3.8%, 7.3% and 6.17% for moving average, linear regression and cubic regression, respectively. In this work, we show an analysis

  6. A seismologically consistent expression for the total area and volume of earthquake-triggered landsliding

    NASA Astrophysics Data System (ADS)

    Marc, Odin; Hovius, Niels; Meunier, Patrick; Gorum, Tolga; Uchida, Taro

    2016-04-01

    We present a new, seismologically consistent expression for the total area and volume of populations of earthquake-triggered landslides. This model builds on a set of scaling relationships between key parameters, such as landslide spatial density, seismic ground acceleration, fault length, earthquake source depth, and seismic moment. To assess the model we have assembled and normalized a catalog of landslide inventories for 40 shallow, continental earthquakes. Low landscape steepness causes systematic overprediction of the total area and volume of landslides. When this effect is accounted for, the model predicts the total landslide volume of 63% of 40 cases to within a factor 2 of the volume estimated from observations (R2=0.76). The prediction of total landslide area is also sensitive to the landscape steepness, but less so than the total volume, and it appears to be sensitive to controls on the landslide size-frequency distribution, and possibly the shaking duration. Some outliers are likely associated with exceptionally strong rock mass in the epicentral area, while others may be related to seismic source complexities ignored by the model. However, the close match between prediction and estimate for about two thirds of cases in our database suggests that rock mass strength is similar in many cases and that our simple seismic model is often adequate, despite the variety of lithologies and tectonic settings covered. This makes our expression suitable for integration into landscape evolution models and application to the anticipation or rapid assessment of secondary hazards associated with earthquakes.

  7. Post Earthquake Investigation Of The Mw7.8 Haida Gwaii, Canada, Rupture Area And Constraints On Earthquake Source Models

    NASA Astrophysics Data System (ADS)

    Haeussler, P. J.; Witter, R. C.; Wang, K.

    2013-12-01

    The October 28, 2012 Mw 7.8 Haida Gwaii, British Columbia, earthquake was the second largest historical earthquake recorded in Canada. Earthquake 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 models 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 model 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 earthquake. 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

  8. St. Louis Area Earthquake Hazards Mapping Project - December 2008-June 2009 Progress Report

    USGS Publications Warehouse

    Williams, R.A.; Bauer, R.A.; Boyd, O.S.; Chung, J.; Cramer, C.H.; Gaunt, D.A.; Hempen, G.L.; Hoffman, D.; McCallister, N.S.; Prewett, J.L.; Rogers, J.D.; Steckel, P.J.; Watkins, C.M.

    2009-01-01

    This report summarizes the mission, the project background, the participants, and the progress of the St. Louis Area Earthquake Hazards Mapping Project (SLAEHMP) for the period from December 2008 through June 2009. During this period, the SLAEHMP held five conference calls and two face-to-face meetings in St. Louis, participated in several earthquake awareness public meetings, held one outreach field trip for the business and government community, collected and compiled new borehole and digital elevation data from partners, and published a project summary.

  9. Earthquake scenario ground motions for the urban area of Evansville, Indiana

    USGS Publications Warehouse

    Haase, Jennifer S.; Nowack, Robert L.; Cramer, Chris H.; Boyd, Oliver S.; Bauer, Robert A.

    2011-01-01

    The Wabash Valley seismic zone and the New Madrid seismic zone are the closest large earthquake source zones to Evansville, Indiana. The New Madrid earthquakes of 1811-1812, over 180 kilometers (km) from Evansville, produced ground motions with a Modified Mercalli Intensity of VII near Evansville, the highest intensity observed in Indiana. Liquefaction evidence has been documented less than 40 km away from Evansville resulting from two large earthquakes in the past 12,000 years in the Wabash Valley. Two earthquake scenarios are described in this paper that demonstrate the expected ground motions for a 33×42-km region around Evansville based on a repeat earthquake from each of these source regions. We perform a one-dimensional analysis for a grid of sites that takes into account the amplification or deamplification of ground motion in the unconsolidated soil layer using a new three-dimensional model of seismic velocity and bedrock depth. There are significant differences in the calculated amplification from that expected for National Earthquake Hazard Reduction Program site class D conditions, with deamplification at many locations within the ancient bedrock valley underlying Evansville. Ground motions relative to the acceleration of gravity (g) in the Evansville area from a simulation of a magnitude (M) 7.7 New Madrid earthquake range from 0.15 to 0.25 g for peak ground acceleration, 0.14 to 0.7 g for 0.2-second (s) spectral acceleration, and 0.05 to 0.25 g for 1.0-s spectral acceleration. Ground motions from a M6.8 Wabash Valley earthquake centered 40 km northwest of the city produce ground motions that decrease with distance from 1.5 to 0.3 g for 0.2-s spectral acceleration when they reach the main part of Evansville, but then increase in amplitude from 0.3 to 0.6 g south of the city and the Ohio River. The densest urbanization in Evansville and Henderson, Ky., is within the area of preferential amplification at 1.0-s period for both scenarios, but the area

  10. Earthquake Rate Model 2.2 of the 2007 Working Group for California Earthquake Probabilities, Appendix D: Magnitude-Area Relationships

    USGS Publications Warehouse

    Stein, Ross S.

    2007-01-01

    Summary To estimate the down-dip coseismic fault dimension, W, the Executive Committee has chosen the Nazareth and Hauksson (2004) method, which uses the 99% depth of background seismicity to assign W. For the predicted earthquake magnitude-fault area scaling used to estimate the maximum magnitude of an earthquake rupture from a fault's length, L, and W, the Committee has assigned equal weight to the Ellsworth B (Working Group on California Earthquake Probabilities, 2003) and Hanks and Bakun (2002) (as updated in 2007) equations. The former uses a single relation; the latter uses a bilinear relation which changes slope at M=6.65 (A=537 km2).

  11. Earthquake hypocenter relocation using double difference method in East Java and surrounding areas

    SciTech Connect

    C, Aprilia Puspita; Nugraha, Andri Dian; Puspito, Nanang T

    2015-04-24

    Determination of precise hypocenter location is very important in order to provide information about subsurface fault plane and for seismic hazard analysis. In this study, we have relocated hypocenter earthquakes in Eastern part of Java and surrounding areas from local earthquake data catalog compiled by Meteorological, Climatological, and Geophysical Agency of Indonesia (MCGA) in time period 2009-2012 by using the double-difference method. The results show that after relocation processes, there are significantly changes in position and orientation of earthquake hypocenter which is correlated with the geological setting in this region. We observed indication of double seismic zone at depths of 70-120 km within the subducting slab in south of eastern part of Java region. Our results will provide useful information for advance seismological studies and seismic hazard analysis in this study.

  12. Earthquake hypocenter relocation using double difference method in East Java and surrounding areas

    NASA Astrophysics Data System (ADS)

    C, Aprilia Puspita; Nugraha, Andri Dian; Puspito, Nanang T.

    2015-04-01

    Determination of precise hypocenter location is very important in order to provide information about subsurface fault plane and for seismic hazard analysis. In this study, we have relocated hypocenter earthquakes in Eastern part of Java and surrounding areas from local earthquake data catalog compiled by Meteorological, Climatological, and Geophysical Agency of Indonesia (MCGA) in time period 2009-2012 by using the double-difference method. The results show that after relocation processes, there are significantly changes in position and orientation of earthquake hypocenter which is correlated with the geological setting in this region. We observed indication of double seismic zone at depths of 70-120 km within the subducting slab in south of eastern part of Java region. Our results will provide useful information for advance seismological studies and seismic hazard analysis in this study.

  13. Increases in seismicity rate in the Tokyo Metropolitan area after the 2011 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Ishibe, T.; Satake, K.; Sakai, S.; Shimazaki, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.

    2013-12-01

    Abrupt increases in seismicity rate have been observed in the Kanto region, where the Tokyo Metropolitan area is located, after the 2011 off the Pacific coast of Tohoku earthquake (M9.0) on March 11, 2011. They are well explained by the static increases in the Coulomb Failure Function (ΔCFF) imparted by the gigantic thrusting while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration, post-seismic slip) may also contribute the rate changes. Because of various types of earthquakes with different focal mechanisms occur in the Kanto region, the receiver faults for the calculation of ΔCFF were assumed to be two nodal planes of small earthquakes before and after the Tohoku earthquake. The regions where seismicity rate increased after the Tohoku earthquake well correlate with concentration on positive ΔCFF (i.e., southwestern Ibaraki and northern Chiba prefectures where intermediate-depth earthquakes occur, and in the shallow crust of western Kanagawa, eastern Shizuoka, and southeastern Yamanashi including the Izu and Hakone regions). The seismicity rate has increased since March 11, 2011 with respect to the Epidemic Type Aftershock Sequence (ETAS) model (Ogata, 1988), suggesting that the rate increase was due to the stress increase by the Tohoku earthquake. Furthermore, the z-values immediately after the Tohoku earthquake show the minimum values during the recent 10 years, indicating significant increases in seismicity rate. At intermediate depth, abrupt increases in thrust faulting earthquakes are well consistent with the Coulomb stress increase. At shallow depth, the earthquakes with the T-axes of roughly NE-SW were activated probably due to the E-W extension of the overriding continental plate, and this is also well explained by the Coulomb stress increase. However, the activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased rate of seismicity in the southwestern

  14. Geospatial and geophysical information for earthquake hazard assessment in Vrancea area, Romania

    NASA Astrophysics Data System (ADS)

    Zoran, Maria

    2010-05-01

    Vrancea area at the sharp bend of the Southeast Carpathians in Romania is one of the highest seismogenic zones in Europe, the present-day tectonic activity in this region being characterized by a small zone of intense shallow- to intermediate-depth seismicity that is often interpreted as reflecting the late stage of intra-continental collision. Efforts to advance understanding of earthquake physics and assessing of earthquake hazard in Vrancea seismic area require detailed observations of all phases of the earthquake cycle (pre-, co-, and post-seismic), across multiple fault systems and tectonic environment. Earthquake prediction has two potentially compatible but distinctly different objectives: (a) phenomena that provide information about the future earthquake hazard useful to those who live in earthquake-prone regions and (b) phenomena causally related to the physical processes governing failure on a fault that will improve our understanding of those processes. Remote sensing and geospatial information tools and techniques, including numerical modeling, have advanced considerably in recent years, enabling a greater understanding of the Earth as a complex system of geophysical phenomena. Space-based geodetic measurements using the Global Positioning System in synergy with ground-based seismological measurements, interferometric synthetic aperture radar data, high-resolution digital elevation models as well imaging spectroscopy (e.g. using ASTER, MODIS and Hyperion data) are contributing significantly to seismic hazard and risk assessment. Space-time anomalies of Earth's emitted radiation (radon in underground water and soil and surface air , thermal infrared in spectral range measured from satellite months to weeks before the occurrence of earthquakes etc.), ionospheric and electromagnetic anomalies have been interpreted, by several authors, as pre-seismic signals. For seismic hazard analysis in Vrancea area, Romania have been selected the earthquake precursors

  15. Emergency response and medical rescue in the worst hit Mianyang areas after the Wenchuan earthquake.

    PubMed

    Lei, Bai Ling; Zhou, Yun; Zhu, Ying; Huang, Xuan Yin; Han, Si Run; Ma, Qiang; He, Jing; Li, Yong Qing

    2008-11-01

    The 12 May 2008 earthquake caused damage to 88% of the health systems in the worst hit areas of Mianyang with 326 casualties and the direct economic loss of RMB 3124 billion. Within 30 minutes of the earthquake, the Mianyang headquarters for earthquake disaster relief and the Mianyang public health headquarters for medical rescue and treatment were organized. Five medical teams were sent to Beichuang County, the worst hit Mianyang area, four hours after the earthquake. A total of 22,947 wounded and sick people were delivered to local hospitals after simple triage and rapid treatment through three stations. By 30 June, the Mianyang medical organization had received 379,600 people and admitted 21,628 inpatients. These 2772 severely wounded (including 146 with limbs amputated and 846 who died in hospital). Since 17 May, 3381 wounded had been transferred to 14 provincial and city-level hospitals across China. On 20 June, the Mianyang Rehabilitation Center for wounded and sick people was established and received 156 rehabilitation inpatients. Together with the medical team for psychological intervention, they provided psychological support for over 70,000 people. Within two hours of the earthquake, the Mianyang Organization for Health and Epidemic Control and Prevention launched the emergency response plan for major natural disasters. The organization sent emergency teams for disease prevention and control and completed disinfection and burial of corpses and disposal of carcasses, monitoring of water quality and epidemics, disinfection of environmental ruins, epidemic control in resettled areas, precautions against secondary disasters caused by the earthquake, and large-scale health education. The emergency command system for medical rescue and disease control and prevention in the Mianyang areas integrated resources, carried out unified command, and responded rapidly. Furthermore, the headquarters of medical relief co-ordinated and united the governmental and

  16. Subducting seamounts control interplate coupling and seismic rupture in the 2014 Iquique earthquake area.

    PubMed

    Geersen, Jacob; Ranero, César R; Barckhausen, Udo; Reichert, Christian

    2015-01-01

    To date, the parameters that determine the rupture area of great subduction zone earthquakes remain contentious. On 1 April 2014, the Mw 8.1 Iquique earthquake ruptured a portion of the well-recognized northern Chile seismic gap but left large highly coupled areas un-ruptured. Marine seismic reflection and swath bathymetric data indicate that structural variations in the subducting Nazca Plate control regional-scale plate-coupling variations, and the limited extent of the 2014 earthquake. Several under-thrusting seamounts correlate to the southward and up-dip arrest of seismic rupture during the 2014 Iquique earthquake, thus supporting a causal link. By fracturing of the overriding plate, the subducting seamounts are likely further responsible for reduced plate-coupling in the shallow subduction zone and in a lowly coupled region around 20.5°S. Our data support that structural variations in the lower plate influence coupling and seismic rupture offshore Northern Chile, whereas the structure of the upper plate plays a minor role. PMID:26419949

  17. Subducting seamounts control interplate coupling and seismic rupture in the 2014 Iquique earthquake area

    PubMed Central

    Geersen, Jacob; Ranero, César R.; Barckhausen, Udo; Reichert, Christian

    2015-01-01

    To date, the parameters that determine the rupture area of great subduction zone earthquakes remain contentious. On 1 April 2014, the Mw 8.1 Iquique earthquake ruptured a portion of the well-recognized northern Chile seismic gap but left large highly coupled areas un-ruptured. Marine seismic reflection and swath bathymetric data indicate that structural variations in the subducting Nazca Plate control regional-scale plate-coupling variations, and the limited extent of the 2014 earthquake. Several under-thrusting seamounts correlate to the southward and up-dip arrest of seismic rupture during the 2014 Iquique earthquake, thus supporting a causal link. By fracturing of the overriding plate, the subducting seamounts are likely further responsible for reduced plate-coupling in the shallow subduction zone and in a lowly coupled region around 20.5°S. Our data support that structural variations in the lower plate influence coupling and seismic rupture offshore Northern Chile, whereas the structure of the upper plate plays a minor role. PMID:26419949

  18. Subducting seamounts control interplate coupling and seismic rupture in the 2014 Iquique earthquake area.

    PubMed

    Geersen, Jacob; Ranero, César R; Barckhausen, Udo; Reichert, Christian

    2015-09-30

    To date, the parameters that determine the rupture area of great subduction zone earthquakes remain contentious. On 1 April 2014, the Mw 8.1 Iquique earthquake ruptured a portion of the well-recognized northern Chile seismic gap but left large highly coupled areas un-ruptured. Marine seismic reflection and swath bathymetric data indicate that structural variations in the subducting Nazca Plate control regional-scale plate-coupling variations, and the limited extent of the 2014 earthquake. Several under-thrusting seamounts correlate to the southward and up-dip arrest of seismic rupture during the 2014 Iquique earthquake, thus supporting a causal link. By fracturing of the overriding plate, the subducting seamounts are likely further responsible for reduced plate-coupling in the shallow subduction zone and in a lowly coupled region around 20.5°S. Our data support that structural variations in the lower plate influence coupling and seismic rupture offshore Northern Chile, whereas the structure of the upper plate plays a minor role.

  19. Fluid regime in the source and preparation area of an earthquake

    NASA Astrophysics Data System (ADS)

    Kissin, I. G.

    2016-09-01

    Peculiarities of the fluid regime in the source and in the area of preparation of an earthquake which accommodates the evolution of the precursors are considered. The qualitative characteristics and the conditions of migration of the fluids, as well as their influence on the disjunctive deformations of the crust are discussed. During the development of the earthquake source, the fluid regime in this area depends on the redistribution of the fluids and their inflow from the outside. The fluid inflow and the increase in the fluid pressure are mainly due to the filtering from the subvertical permeable faults and the metamorphic dehydration of the rocks in the walls of the main fault. The fluids may also be supplied to the source from the near-surface horizons, and most of the induced earthquakes are associated with this process. These earthquakes can be considered as large-scale natural experiments which can shed light on the contribution of fluids in this phenomenon. A particular role in the mechanism of natural seismicity is played by the inflow of high-pressure fluids through the faults from the deep zones of the section.

  20. Synergistic use of geospatial and in-situ data for earthquake hazard assessment in Vrancea area

    NASA Astrophysics Data System (ADS)

    Zoran, M. A.; Savastru, R. S.; Savastru, D. M.

    2016-08-01

    Space-time anomalies of Earth's emitted radiation: thermal infrared in spectral range measured from satellite months to weeks before the occurrence of earthquakes, radon in underground water and soil, etc., and electromagnetic anomalies are considered as pre-seismic signals. Satellite remote sensing provides spatially continuous information of the tectonic landscape but also contribute to the understanding of specific fault and information about stress transfer between fault systems from depth and to the surface as well as on released energy by earthquakes and other modes of deformation. This paper presents observations made using time series MODIS Terra/Aqua, NOAA-AVHRR, Landsat satellite data for derived multi-parameters land surface temperature (LST), outgoing long-wave radiation (OLR), and mean air temperature (AT) for some seismic events recorded in Vrancea active geotectonic region in Romania. For some analyzed earthquakes, starting with almost one week prior to a moderate or strong earthquake a transient thermal infrared rise in LST of several Celsius degrees (oC) and the increased OLR values higher than the normal function of the magnitude and focal depth, which disappeared after the main shock. Synergy of multisenzor and multitemporal satellite data with in-situ and GPS data and spatial analysis of magnitude-frequency distributions of Vrancea earthquakes provides more information on Vrancea area seismicity. Earthquake hazard assessment for Vrancea region in Romania must have different degrees of complexity, which consists of derived geospatial and in-situ geophysical/geodetic parameters monitoring, analysis, predictive modeling, and forecast-oriented as well as decision-making procedures.

  1. Expectable Earthquakes and their ground motions in the Van Norman Reservoirs Area

    USGS Publications Warehouse

    Wesson, R.L.; Page, R.A.; Boore, D.M.; Yerkes, R.F.

    1974-01-01

    The upper and lower Van Norman dams, in northwesternmost San Fernando Valley about 20 mi (32 km) northwest of downtown Los Angeles, were severely damaged during the 1971 San Fernando earthquake. An investigation of the geologic-seismologic setting of the Van Norman area indicates that an earthquake of at least M 7.7 may be expected in the Van Norman area. The expectable transitory effects in the Van Norman area of such an earthquake are as follows: peak horizontal acceleration of at least 1.15 g, peak velocity of displacement of 4.43 ft/sec (135 cm/sec), peak displacement of 2.3 ft (70 cm), and duration of shaking at accelerations greater than 0.05 g, 40 sec. A great earthquake (M 8+) on the San Andreas fault, 25 mi distant, also is expectable. Transitory effects in the Van Norman area from such an earthquake are estimated as follows: peak horizontal acceleration of 0.5 g, peak velocity of 1.97 ft/sec (60 cm/sec), displacement of 1.31 ft (40 cm), and duration of shaking at accelerations greater than 0.05 g, 80 sec. The permanent effects of the expectable local earthquake could include simultaneous fault movement at the lower damsite, the upper damsite, and the site proposed for a replacement dam halfway between the upper and lower dams. The maximum differential displacements due to such movements are estimated at 16.4 ft (5 m) at the lower damsite and about 9.6 ft (2.93 m) at the upper and proposed damsites. The 1971 San Fernando earthquake (M 6?) was accompanied by the most intense ground motions ever recorded instrumentally for a natural earthquake. At the lower Van Norman dam, horizontal accelerations exceeded 0.6 g, and shaking greater than 0.25 g lasted for about 13 see; at Pacoima dam, 6 mi (10 km) northeast of the lower dam, high-frequency peak horizontal accelerations of 1.25 g were recorded in two directions, and shaking greater than 0.25 g lasted for about 7 sec. Permanent effects of the earthquake include slope failures in the embankments of the upper

  2. Spatial distribution of crack structure in the focal area of a volcanic earthquake swarm at the Hakone volcano, Japan

    NASA Astrophysics Data System (ADS)

    Nihara, Yu; Tadokoro, Keiichi; Yukutake, Yohei; Honda, Ryou; Ito, Hiroshi

    2013-01-01

    We have performed shear wave splitting analyses for seismograms recorded at stations located just above, and outside, the focal area of the earthquake swarm at the Hakone volcano, Japan, in August 2009. Average values of the direction of faster split shear wave polarization (Φ) at two stations above the focal area correspond to each focal alignment of the earthquake swarm. In contrast, average values of Φ at three stations outside the focal area correspond to the direction of the maximum horizontal compressional stress. We found that the average values of the time lag between the two split shear waves inside the focal area are relatively high compared with those outside the focal area. These facts suggest that cracks with a high density aligned parallel to the faults of the earthquake swarm in the focal area. Crustal fluid was selectively injected into this pre-existing cracked media accompanied by effective normal stress reduction in the cracks, resulting in the earthquake swarm.

  3. [Experience of DMAT rescue activity by doctor-helicopter in Tohoku Area after the earthquake].

    PubMed

    Otsuka, Naomi; Yamashita, Ako; Kimura, Yoshinobu; Aimono, Mako; Kobayashi, Iwao; Nanba, Hitoshi; Watanabe, Akihiko; Sumita, Shinzou

    2012-07-01

    We operated rescue activities in Tohoku area after the earthquake of March 11th, 2011. From our hospital, a doctor-helicopter flew to the staging care unit at Hanamaki airport with two members of the disaster medical assistance team (DMAT), one of whom was an anesthesiologist. The helicopter carried ten patients by nine flight missions, who were the victims of tsunami after the earthquake. There were seven doctor-helicopters from all over Japan and did the missions based at Hanamaki airport. The missions was quite different from our usual job as an anesthesiologist, but we could transfer the patients safely by using some knowledge of stabilizing the unstable patients as flight doctors. We report the details of our activities by our doctor-helicopters in Tohoku area.

  4. Surface Colonization and Activity of the 2,6-Dichlorobenzamide (BAM) Degrading Aminobacter sp. Strain MSH1 at Macro- and Micropollutant BAM Concentrations.

    PubMed

    Sekhar, Aswini; Horemans, Benjamin; Aamand, Jens; Sørensen, Sebastian R; Vanhaecke, Lynn; Bussche, Julie Vanden; Hofkens, Johan; Springael, Dirk

    2016-09-20

    Aminobacter sp. MSH1 uses the groundwater micropollutant 2,6-dichlorobenzamide (BAM) as a C and N source and is a potential catalyst for biotreatment of BAM-contaminated groundwater in filtration units of drinking water treatment plants (DWTPs). The oligotrophic environment of DWTPs including trace pollutant concentrations, and the high flow rates impose challenges for micropollutant biodegradation in DWTPs. To understand how trace BAM concentrations affect MSH1 surface colonization and BAM degrading activity, MSH1 was cultivated in flow channels fed continuously with BAM macro- and microconcentrations in a N- and C-limiting medium. At all BAM concentrations, MSH1 colonized the flow channel. BAM degradation efficiencies were concentration-dependent, ranging between 70 and 95%. Similarly, BAM concentration affected surface colonization, but at 100 μg/L BAM and lower, colonization was similar to that in systems without BAM, suggesting that assimilable organic carbon and nitrogen other than those supplied by BAM sustained colonization at BAM microconcentrations. Comparison of specific BAM degradation rates in flow channels and in cultures of suspended freshly grown cells indicated that starvation conditions in flow channels receiving BAM microconcentrations resulted into MSH1 biomasses with 10-100-times reduced BAM degrading activity and provided a kinetic model for predicting BAM degradation under continuous C and N starvation.

  5. Surface Colonization and Activity of the 2,6-Dichlorobenzamide (BAM) Degrading Aminobacter sp. Strain MSH1 at Macro- and Micropollutant BAM Concentrations.

    PubMed

    Sekhar, Aswini; Horemans, Benjamin; Aamand, Jens; Sørensen, Sebastian R; Vanhaecke, Lynn; Bussche, Julie Vanden; Hofkens, Johan; Springael, Dirk

    2016-09-20

    Aminobacter sp. MSH1 uses the groundwater micropollutant 2,6-dichlorobenzamide (BAM) as a C and N source and is a potential catalyst for biotreatment of BAM-contaminated groundwater in filtration units of drinking water treatment plants (DWTPs). The oligotrophic environment of DWTPs including trace pollutant concentrations, and the high flow rates impose challenges for micropollutant biodegradation in DWTPs. To understand how trace BAM concentrations affect MSH1 surface colonization and BAM degrading activity, MSH1 was cultivated in flow channels fed continuously with BAM macro- and microconcentrations in a N- and C-limiting medium. At all BAM concentrations, MSH1 colonized the flow channel. BAM degradation efficiencies were concentration-dependent, ranging between 70 and 95%. Similarly, BAM concentration affected surface colonization, but at 100 μg/L BAM and lower, colonization was similar to that in systems without BAM, suggesting that assimilable organic carbon and nitrogen other than those supplied by BAM sustained colonization at BAM microconcentrations. Comparison of specific BAM degradation rates in flow channels and in cultures of suspended freshly grown cells indicated that starvation conditions in flow channels receiving BAM microconcentrations resulted into MSH1 biomasses with 10-100-times reduced BAM degrading activity and provided a kinetic model for predicting BAM degradation under continuous C and N starvation. PMID:27537851

  6. Microzonation of Seismic Hazards and Estimation of Human Fatality for Scenario Earthquakes in Chianan Area, Taiwan

    NASA Astrophysics Data System (ADS)

    Liu, K. S.; Chiang, C. L.; Ho, T. T.; Tsai, Y. B.

    2015-12-01

    In this study, we assess seismic hazards in the 57 administration districts of Chianan area, Taiwan in the form of ShakeMaps as well as to estimate potential human fatalities from scenario earthquakes on the three Type I active faults in this area. As a result, it is noted that two regions with high MMI intensity greater than IX in the map of maximum ground motion. One is in the Chiayi area around Minsyong, Dalin and Meishan due to presence of the Meishan fault and large site amplification factors which can reach as high as 2.38 and 2.09 for PGA and PGV, respectively, in Minsyong. The other is in the Tainan area around Jiali, Madou, Siaying, Syuejia, Jiangjyun and Yanshuei due to a disastrous earthquake occurred near the border between Jiali and Madou with a magnitude of Mw 6.83 in 1862 and large site amplification factors which can reach as high as 2.89 and 2.97 for PGA and PGV, respectively, in Madou. In addition, the probabilities in 10, 30, and 50-year periods with seismic intensity exceeding MMII VIII in above areas are greater than 45%, 80% and 95%, respectively. Moreover, from the distribution of probabilities, high values of greater than 95% over a 10 year period with seismic intensity corresponding to CWBI V and MMI VI are found in central and northern Chiayi and northern Tainan. At last, from estimation of human fatalities for scenario earthquakes on three active faults in Chianan area, it is noted that the numbers of fatalities increase rapidly for people above age 45. Compared to the 1946 Hsinhua earthquake, the number of fatality estimated from the scenario earthquake on the Hsinhua active fault is significantly high. However, the higher number of fatality in this case is reasonable after considering the probably reasons. Hence, we urge local and the central governments to pay special attention on seismic hazard mitigation in this highly urbanized area with large number of old buildings.

  7. When it happens again: impact of future San Francisco Bay area earthquakes

    NASA Astrophysics Data System (ADS)

    Zoback, M.; Boatwright, J.; Kornfield, L.; Scawthorn, C.; Rojahn, C.

    2005-12-01

    San Francisco Bay area earthquakes, like major floods and hurricanes, have the potential for massive damage to dense urban population centers concentrated in vulnerable zones-along active faults, in coastal regions, and along major river arteries. The recent destruction of Hurricane Katrina does have precedent in the destruction following the 1906 "San Francisco" earthquake and fire in which more than 3000 people were killed and 225,000 were left homeless in San Francisco alone, a city of 400,000 at the time. Analysis of a comprehensive set of damage reports from the magnitude (M) 7.9 1906 earthquake indicates a region of ~ 18,000 km2 was subjected to shaking of Modified Mercalli Intensity of VIII or more - motions capable of damaging even modern, well-built structures; more than 60,000 km2 was subjected to shaking of Intensity VII or greater - the threshold for damage to masonry and poorly designed structures. By comparison, Katrina's hurricane force winds and intense rainfall impacted an area of ~100,000 km2 on the Gulf Coast. Thus, the anticipated effects of a future major Bay Area quake to lives, property, and infrastructure are comparable in scale to Katrina. Secondary hazards (levee failure and flooding in the case of Katrina and fire following the 1906 earthquake) greatly compounded the devastation in both disasters. A recent USGS-led study concluded there is a 62% chance of one or more damaging (M6.7 or greater) earthquakes striking the greater San Francisco Bay area over the next 30 years. The USGS prepared HAZUS loss estimates for the 10 most likely forecast earthquakes which range in size from a M6.7 event on a blind thrust to the largest anticipated event, a M7.9 repeat of the 1906 earthquake. The largest economic loss is expected for a repeat of the 1906 quake. Losses in the Bay region for this event are nearly double those predicted for a M6.9 rupture of the entire Hayward Fault in the East Bay. However, because of high density of population along the

  8. Three-dimensional ground-motion simulations of earthquakes for the Hanford area, Washington

    USGS Publications Warehouse

    Frankel, Arthur; Thorne, Paul; Rohay, Alan

    2014-01-01

    This report describes the results of ground-motion simulations of earthquakes using three-dimensional (3D) and one-dimensional (1D) crustal models conducted for the probabilistic seismic hazard assessment (PSHA) of the Hanford facility, Washington, under the Senior Seismic Hazard Analysis Committee (SSHAC) guidelines. The first portion of this report demonstrates that the 3D seismic velocity model for the area produces synthetic seismograms with characteristics (spectral response values, duration) that better match those of the observed recordings of local earthquakes, compared to a 1D model with horizontal layers. The second part of the report compares the response spectra of synthetics from 3D and 1D models for moment magnitude (M) 6.6–6.8 earthquakes on three nearby faults and for a dipping plane wave source meant to approximate regional S-waves from a Cascadia great earthquake. The 1D models are specific to each site used for the PSHA. The use of the 3D model produces spectral response accelerations at periods of 0.5–2.0 seconds as much as a factor of 4.5 greater than those from the 1D models for the crustal fault sources. The spectral accelerations of the 3D synthetics for the Cascadia plane-wave source are as much as a factor of 9 greater than those from the 1D models. The differences between the spectral accelerations for the 3D and 1D models are most pronounced for sites with thicker supra-basalt sediments and for stations with earthquakes on the Rattlesnake Hills fault and for the Cascadia plane-wave source.

  9. A robust satellite technique for monitoring seismically active areas: The case of Bhuj Gujarat earthquake

    NASA Astrophysics Data System (ADS)

    Genzano, N.; Aliano, C.; Filizzola, C.; Pergola, N.; Tramutoli, V.

    2007-02-01

    A robust satellite data analysis technique (RAT) has been recently proposed as a suitable tool for satellite TIR surveys in seismically active regions and already successfully tested in different cases of earthquakes (both high and medium-low magnitudes). In this paper, the efficiency and the potentialities of the RAT technique have been tested even when it is applied to a wide area with extremely variable topography, land coverage and climatic characteristics (the whole Indian subcontinent). Bhuj-Gujarat's earthquake (occurred on 26th January 2001, MS ˜ 7.9) has been considered as a test case in the validation phase, while a relatively unperturbed period (no earthquakes with MS ≥ 5, in the same region and in the same period) has been analyzed for confutation purposes. To this aim, 6 years of Meteosat-5 TIR observations have been processed for the characterization of the TIR signal behaviour at each specific observation time and location. The anomalous TIR values, detected by RAT, have been evaluated in terms of time-space persistence in order to establish the existence of actually significant anomalous transients. The results indicate that the studied area was affected by significant positive thermal anomalies which were identified, at different intensity levels, not far from the Gujarat coast (since 15th January, but with a clearer evidence on 22nd January) and near the epicentral area (mainly on 21st January). On 25th January (1 day before Gujarat's earthquake) significant TIR anomalies appear on the Northern Indian subcontinent, showing a remarkable coincidence with the principal tectonic lineaments of the region (thrust Himalayan boundary). On the other hand, the results of the confutation analysis indicate that no meaningful TIR anomalies appear in the absence of seismic events with MS ≥ 5.

  10. Non-shear focal mechanisms of earthquakes at The Geysers, California and Hengill, Iceland, geothermal areas

    USGS Publications Warehouse

    Julian, B.R.; Miller, A.D.; Foulger, G.R.; ,

    1993-01-01

    Several thousand earthquakes were recorded in each area. We report an initial investigation of the focal mechanisms based on P-wave polarities. Distortion by complicated three-dimensional crustal structure was minimized using tomographically derived three-dimensional crustal models. Events with explosive and implosive source mechanisms, suggesting cavity opening and collapse, have been tentatively identified at The Geysers. The new data show that some of these events do not fit the model of tensile cracking accompanied by isotropic pore pressure decreases that was suggested in earlier studies, but that they may instead involve combination of explosive and shear processes. However, the confirmation of earthquakes dominated by explosive components supports the model that the event are caused by crack opening induced by thermal contraction of the heat source.

  11. Source processes of industrially-induced earthquakes at the Geysers geothermal area, California

    USGS Publications Warehouse

    Ross, A.; Foulger, G.R.; Julian, B.R.

    1999-01-01

    Microearthquake activity at The Geysers geothermal area, California, mirrors the steam production rate, suggesting that the earthquakes are industrially induced. A 15-station network of digital, three-component seismic stations was operated for one month in 1991, and 3,900 earthquakes were recorded. Highly-accurate moment tensors were derived for 30 of the best recorded earthquakes by tracing rays through tomographically derived 3-D VP and VP / VS structures, and inverting P-and S-wave polarities and amplitude ratios. The orientations of the P-and T-axes are very scattered, suggesting that there is no strong, systematic deviatoric stress field in the reservoir, which could explain why the earthquakes are not large. Most of the events had significant non-double-couple (non-DC) components in their source mechanisms with volumetric components up to ???30% of the total moment. Explosive and implosive sources were observed in approximately equal numbers, and must be caused by cavity creation (or expansion) and collapse. It is likely that there is a causal relationship between these processes and fluid reinjection and steam withdrawal. Compensated linear vector dipole (CLVD) components were up to 100% of the deviatoric component. Combinations of opening cracks and shear faults cannot explain all the observations, and rapid fluid flow may also be involved. The pattern of non-DC failure at The Geysers contrasts with that of the Hengill-Grensdalur area in Iceland, a largely unexploited water-dominated field in an extensional stress regime. These differences are poorly understood but may be linked to the contrasting regional stress regimes and the industrial exploitation at The Geysers.

  12. Did stress field change after the 2011 Tohoku-Oki earthquake in the inland areas of Tohoku?

    NASA Astrophysics Data System (ADS)

    Yoshida, K.; Hasegawa, A.; Okada, T.; Nakajima, J.; Iinuma, T.; Ito, Y.; Asano, Y.

    2012-12-01

    We investigated the stress field in the inland area of Tohoku to clarify whether the 2011 Tohoku-oki earthquake changed the stress field or not based on the new arrival time and initial-motion polarity data that were observed at seismic stations in Akita Prefecture and near Iwaki City, where the change in the orientation of the principal stress axis has already been reported by Yoshida et al. [2012, GRL]. We first relocated hypocenters by the double-difference location method. Focal mechanisms are estimated using initial-motion polarity data with the relocated hypocenters. Then, we estimated stress fields before and after the Tohoku-oki earthquake by applying the stress tensor inversion method to the well-estimated focal mechanism solutions. The total numbers of focal mechanisms analyzed for the pre-Tohoku-oki earthquake period are 140 and 67 in Akita Prefecture and near Iwaki City, respectively. The total numbers for the post-Tohoku-oki earthquake period are 260 and 580, respectively. These focal mechanisms were determined not only in this study but also in other studies. Orientations of the principal stress axes estimated after the Tohoku-oki earthquake differ significantly from those before the earthquake in Akita Prefecture. The σ1 axis was horizontally oriented in E-W direction and the σ3 axis was vertical before the Tohoku-oki Earthquake, while the σ1 and σ3 axes are oriented in NE-SW and NW-SE directions, respectively, after the earthquake. The σ1 axis estimated before the earthquake was parallel to the plate convergence direction, whereas the σ1 and σ3 axes after the earthquake are oriented in the directions of the static stress change due to the Tohoku-oki earthquake. Since hypocenter distributions before and after the Tohoku-oki earthquake do not show substantial differences, the change in the orientations of the principal stress axes should be caused by the M9 mainshock. On the other hand, a depth dependency of the principal stress directions is

  13. Psychological distress in an earthquake-devastated area with pre-existing high rate of suicide.

    PubMed

    Tachibana, Akira; Kitamura, Hideaki; Shindo, Masanobu; Honma, Hiroko; Someya, Toshiyuki

    2014-10-30

    On 12 March 2011 an earthquake devastated the Matsunoyama and Matsudai districts of Tōkamachi City, Niigata, Japan. These areas had high pre-existing suicide rates, especially among the elderly. We investigated whether mental health status became worse among the sufferers 5 months after the earthquake, and what kind of factors were implicated in any changes. A 15-item questionnaire that tapped earthquake-related variables and the Kessler 10 Psychological Distress Scale to measure psychological distress were distributed to 1923 residents aged over 40 years. The mean age (S.D.) of the total 1731 respondents (male, 805; female, 926) was 68.2 (13.1) years. Of these, we assessed K10 scores from 1346 respondents. The mean scores (S.D.) for K10 and K6 (six selected items from the K10) were 5.8 (6.3) and 3.4 (3.9), respectively. Among the respondents, 9.1% and 3.2% obtained a score of K10 ≥15 and K6 ≥13, respectively. These scores showed slightly higher psychological distress, especially among the elderly, in comparison with existing community-based data. Categorical regression analysis revealed significant and relatively strong effects of initial psychological impact, decrease in sleep hours, advanced age, and decrease in interpersonal relationships within the community on the K10 score. The last item suggests the importance of socio-environmental factors in post-disaster mental health.

  14. Stations Correction and Earthquake hypocenter relocation in the Kalabsha area, Aswan, Egypt

    NASA Astrophysics Data System (ADS)

    Shater, A.

    2012-04-01

    343 earthquakes recorded by more than 7 stations from the Aswan seismic network in the Kalabsha area, are relocated and the seismic stations correction for P-wave are estimated using joint hypocenter determination method. Seven stations AHD, SKD, NMR, GMR, KSR,,GRW, and KRL have minus signs in station P-wave travel time corrections and their values - 0.009, -0.178, -0.070, -0.027, -0.344,-0.123, and -0.067. It is possible to assume that the underground structure in this area has a particular characteristic of high velocity structure and other stations WKL, WAL, GAL, KUR, MAN and NAL have positive sign and their values 0.038, 0.158, 0.065, 0.219, 0.197 and 0.057 respectively. It is possible to assume that underground structure in this area has particular characteristic of low velocity structure. The hypocenter location determined by the joint hypocenter determination method is more precise than those determined by other routine work program. The method simultaneously solves for earthquake location and station corrections. The station corrections reflect not only different crustal condition in the vicinity of the stations, but also the difference between actual and model seismic velocities along each of the earthquake - station ray paths. The station corrections obtained correlate with the major surface geological features in the study area. As a result of the relocation, the majority of the hypocenters shifted upward and the relocated epicenters are closer to the faults than those before relocation.

  15. Deciphering the roles of BamB and its interaction with BamA in outer membrane biogenesis, T3SS expression and virulence in Salmonella.

    PubMed

    Namdari, Fatémeh; Hurtado-Escobar, Genaro Alejandro; Abed, Nadia; Trotereau, Jérôme; Fardini, Yann; Giraud, Etienne; Velge, Philippe; Virlogeux-Payant, Isabelle

    2012-01-01

    The folding and insertion of β-barrel proteins in the outer membrane of Gram-negative bacteria is mediated by the BAM complex, which is composed of the outer membrane protein BamA and four lipoproteins BamB to BamE. In Escherichia coli and/or Salmonella, the BamB lipoprotein is involved in (i) β-barrel protein assembly in the outer membrane, (ii) outer membrane permeability to antibiotics, (iii) the control of the expression of T3SS which are major virulence factors and (iv) the virulence of Salmonella. In E. coli, this protein has been shown to interact directly with BamA. In this study, we investigated the structure-function relationship of BamB in order to assess whether the roles of BamB in these phenotypes were inter-related and whether they require the interaction of BamB with BamA. For this purpose, recombinant plasmids harbouring point mutations in bamB were introduced in a ΔSalmonella bamB mutant. We demonstrated that the residues L173, L175 and R176 are crucial for all the roles of BamB and for the interaction of BamB with BamA. Moreover, the results obtained with a D229A BamB variant, which is unable to immunoprecipitate BamA, suggest that the interaction of BamB with BamA is not absolutely necessary for BamB function in outer-membrane protein assembly, T3SS expression and virulence. Finally, we showed that the virulence defect of the ΔbamB mutant is not related to its increased susceptibility to antimicrobials, as the D227A BamB variant fully restored the virulence of the mutant while having a similar antibiotic susceptibility to the ΔbamB strain. Overall, this study demonstrates that the different roles of BamB are not all inter-related and that L173, L175 and R176 amino-acids are privileged sites for the design of BamB inhibitors that could be used as alternative therapeutics to antibiotics, at least against Salmonella.

  16. Deciphering the Roles of BamB and Its Interaction with BamA in Outer Membrane Biogenesis, T3SS Expression and Virulence in Salmonella

    PubMed Central

    Namdari, Fatémeh; Hurtado-Escobar, Genaro Alejandro; Abed, Nadia; Trotereau, Jérôme; Fardini, Yann; Giraud, Etienne; Velge, Philippe; Virlogeux-Payant, Isabelle

    2012-01-01

    The folding and insertion of β-barrel proteins in the outer membrane of Gram-negative bacteria is mediated by the BAM complex, which is composed of the outer membrane protein BamA and four lipoproteins BamB to BamE. In Escherichia coli and/or Salmonella, the BamB lipoprotein is involved in (i) β-barrel protein assembly in the outer membrane, (ii) outer membrane permeability to antibiotics, (iii) the control of the expression of T3SS which are major virulence factors and (iv) the virulence of Salmonella. In E. coli, this protein has been shown to interact directly with BamA. In this study, we investigated the structure-function relationship of BamB in order to assess whether the roles of BamB in these phenotypes were inter-related and whether they require the interaction of BamB with BamA. For this purpose, recombinant plasmids harbouring point mutations in bamB were introduced in a ΔSalmonella bamB mutant. We demonstrated that the residues L173, L175 and R176 are crucial for all the roles of BamB and for the interaction of BamB with BamA. Moreover, the results obtained with a D229A BamB variant, which is unable to immunoprecipitate BamA, suggest that the interaction of BamB with BamA is not absolutely necessary for BamB function in outer-membrane protein assembly, T3SS expression and virulence. Finally, we showed that the virulence defect of the ΔbamB mutant is not related to its increased susceptibility to antimicrobials, as the D227A BamB variant fully restored the virulence of the mutant while having a similar antibiotic susceptibility to the ΔbamB strain. Overall, this study demonstrates that the different roles of BamB are not all inter-related and that L173, L175 and R176 amino-acids are privileged sites for the design of BamB inhibitors that could be used as alternative therapeutics to antibiotics, at least against Salmonella. PMID:23144780

  17. Solar modulation of earthquake occurrence in areas penetrated by L of 2.0 populated by anomalous cosmic rays

    NASA Astrophysics Data System (ADS)

    Khachikyan, Galina; Inchin, Alexander; Toyshiev, Nursultan

    An analysis of data of global seismological catalog NEIC (National Earthquake Information Center of the U.S. Geological Survey) for 1973-2011 (182933 events with magnitude equal to 4.5 and more) has been carried out with taken into account the geometry of the main geomagnetic field as gives the International Geomagnetic Reference Field (IGRF-11) model. It is found that the greatest number of earthquakes occurs in seismic areas penetrated by the geomagnetic force lines L=1.0-1.1, and additionally, the L-shell distribution of earthquake counting rate is peaked at the L equal to 2.0-2.2, which are inhabited by the Anomalous Cosmic Rays (ACRs). It is revealed that occurrence of strong earthquakes (with magnitude 7.0 and more) in these areas is modulated by the 11 year solar cycle. Namely, during 1973-2011, twenty strong earthquakes occurred in regions where the L=2.0-2.2 are loaned into the earth’s crust and, surprisingly, all of these earthquakes occurred only at the declining phase of the 11 year solar cycles while were absent at the ascending phase. Solar modulation of earthquake occurrence may be explained at present in the frame of a modern idea that earthquake is triggered by the electric currents flowing into the global electric circuit (GEC), where the charged geomagnetic force lines play the role of conductors (field align currents). The operation of GEC depends on intensity of cosmic rays which provide ionization and conductivity of the air in the middle atmosphere. Since the ACRs are especially sensitive to solar modulation, and since they populate the L of 2.0, it may be expected that earthquake occurrence in the areas penetrated by L of 2.0 would be especially sensitive to solar modulation. Our results prove this expectation, but much work is required to study this problem in more details.

  18. P wave crustal velocity structure in the greater Mount Rainier area from local earthquake tomography

    USGS Publications Warehouse

    Moran, S.C.; Lees, J.M.; Malone, S.D.

    1999-01-01

    We present results from a local earthquake tomographic imaging experiment in the greater Mount Rainier area. We inverted P wave arrival times from local earthquakes recorded at permanent and temporary Pacific Northwest Seismograph Network seismographs between 1980 and 1996. We used a method similar to that described by Lees and Crosson [1989], modified to incorporate the parameter separation method for decoupling the hypocenter and velocity problems. In the upper 7 km of the resulting model there is good correlation between velocity anomalies and surface geology. Many focal mechanisms within the St. Helens seismic zone have nodal planes parallel to the epicentral trend as well as to a north-south trending low-velocity trough, leading us to speculate that the trough represents a zone of structural weakness in which a moderate (M 6.5-7.0) earthquake could occur. In contrast, the western Rainier seismic zone does not correlate in any simple way with anomaly patterns or focal mechanism fault planes, leading us to infer that it is less likely to experience a moderate earthquake. A ???10 km-wide low-velocity anomaly occurs 5 to 18 km beneath the summit of Mount Rainier, which we interpret to be a signal of a region composed of hot, fractured rock with possible small amounts of melt or fluid. No systematic velocity pattern is observed in association with the southern Washington Cascades conductor. A midcrustal anomaly parallels the Olympic-Wallowa lineament as well as several other geophysical trends, indicating that it may play an important role in regional tectonics. Copyright 1999 by the American Geophysical Union.

  19. Seafloor seismological/geodetic observations in the rupture area of the 2011 Tohoku-oki Earthquake

    NASA Astrophysics Data System (ADS)

    Hino, Ryota; Shinohara, Masanao; Ito, Yoshihiro

    2016-04-01

    A number of important aspects of the 2011 Tohoku-oki earthquake (Mw 9.0) were clarified by the seafloor seismological and geodetic observation above the rupture area of the earthquake. Besides the extraordinarily large coseismic displacements, various kinds of slow slip phenomena associated with intensive micro-seismicity on the plate boundary fault were identified by near field ocean bottom seismographs and seafloor geodetic observation networks. The Tohoku-oki earthquake was preceded by evident foreshock activity with a spatial expansion of this seismicity. The activity became significantly intense after the occurrence of the largest foreshock two days before the mainshock rupture. During the period, clear continuous seafloor deformation was identified caused by the aseismic slip following the largest foreshock. Another different type of aseismic slip event had occurred before this pre-imminent activity had started about a month before the largest foreshock happened. The observed increased seismicity associated with aseismic slip suggests that there must have been some chain reaction like interplay of seismic and interseismic slips before the large earthquake broke out. However, no evident deformation signals were observed indicating acceleration of fault slip immediately before the mainshock. Seafloor geodetic measurements reveals that the postseismic deformation around the rupture area of the Tohoku-oki earthquake shows complex spatial pattern and the complexity is mostly due to significant viscoelastic relaxation induced by the huge coseismic slip. The effects of viscoelastic deformation makes it difficult to identify the deformation associated with the after slip or regaining of interplate coupling and requires us to enhance the abilities of seafloor monitoring to detect the slip activities on the fault. We started an array of seismometer arrays observation including broad-band seismographs to detect and locate slow-slip events and low-frequency tremors

  20. Gigantic lateral spreading of mountains in the epicentral area of the expected Tokai earthquake, central Japan

    NASA Astrophysics Data System (ADS)

    Chigira, Masahiro; Nakamura, Takeshi

    2010-05-01

    Lateral spreading of mountains is not only a degradation process itself but also it could become the background of a catastrophic landslide that occurs at its spreading rims. We found gigantic lateral spreading behind the Yui landsllide area, which is located along the Pacific Sea coast in the epicentral area of the expected Tokai earthquake, central Japan. The Yui landslide area is located on a socially very important place, where are major lifelines connecting east and west Japan: Tokaido railway, Tokaido Shinkansen, and Tomei highway. The Yui landslide area comprises many landslide units and has been causing many catastrophs. The lateral spreading is characterized by NS-trending multiple ridges and linear depressions as long as 1 to 2 km and up to 60 m deep. These features are observable on the aerial photographs and are clearly identified by using airborne laser scanner. Mountains subjected to the lateral spreading is 3 km wide in EW and 6 km long in NS and are 250 to 500 m high above sea level. These morphological features suggest that the NS trending ridges spread laterally to EW and their central parts settled down like the way by which horsts and grabens are made. The ridges are underlain by Miocene beds consisting of the alternating beds of mudstone and sandstone in the lower part and of sandstone and conglomerate in the upper part. The spreading ridge occupies the axial part of a NS-trending syncline, which has a half wave length longer than 2 km and comprises minor folds with a wavelength on the order of hundred meters. This structure, synclinorium, suggests that there could be decollements along the enveloping surface of the minor folds and that the lateral spreading could have a low-angle slip surface along the enveloping surface of the minor folds. There are many landslides along the side slopes of the laterally spread ridges and they have been moving many times by rainstorms and also by earthquakes. The movements are recorded since 1781, but the

  1. Dichlobenil and 2,6-dichlorobenzamide (BAM) in the environment: what are the risks to humans and biota?

    PubMed

    Björklund, Erland; Styrishave, Bjarne; Anskjær, Gitte Gotholdt; Hansen, Martin; Halling-Sørensen, Bent

    2011-09-01

    Dichlobenil is a herbicide widely used for weed control, mainly in non-agricultural areas and in the aquatic environment. When released into the environment, dichlobenil can undergo many processes such as vaporization to air, binding to soil and sediment, as well as degradation to a number of new compounds. The main metabolite is 2,6-dichlorobenzamide (BAM) which is water soluble and causes ground water contamination. It is frequently found in levels exceeding maximum allowed concentrations of pesticides and metabolites in ground water (0.1 μg/L) set by the European Commission. The environmental distribution of both dichlobenil and BAM was outlined and the risk quotients were calculated for biota and for humans. For organisms living in aquatic habitats, risk quotients were low for both dichlobenil and BAM, approximately 0.02 for dichlobenil and 2.4·10(-4) to 1.3·10(-3) for BAM. For humans, a margin of safety above 15,000 was estimated for dichlobenil. The most unusual and extreme concentration of BAM ever found in ground water is 560 μg/L. Even at this concentration, the margin of safety for humans was 313 for a 70 kilo man and 56 for a 25 kilo child. The results clearly demonstrate that the risks to biota and humans are very low.

  2. a Goes-W Satellite Thermal Infrared Survey (2006-2014) Over South Western us Earthquake Prone Area: Preliminary Results on 24 August 2014 Napa Earthquake (M=6)

    NASA Astrophysics Data System (ADS)

    Tramutoli, V.; Genzano, N.; Coviello, I.; Filizzola, C.; Lisi, M.; Paciello, R.; Pergola, N.; Satriano, V.

    2014-12-01

    The RST (Robust Satellite Technique) methodology has been widely applied to tens of earthquakes occurred in different continents (Europe, Asia, America and Africa), in various geo-tectonic settings (compressive, extensional and transcurrent) and with a wide range of magnitudes (from 4.0 to 7.9) trying to identify anomalous fluctuations of the Earth's emitted TIR (Thermal InfraRed) radiation in possible relation with earthquake occurrence discriminating them from those variations due to other causes. An extended study is presented in the AGU2014 NH008 session by Tramutoli et al. which is devoted to verify to which extent Significant (space-time persistent, non-spurious) Sequences of TIR Anomalies (SSTAs) appear within prefixed space-time windows around earthquakes of magnitude M>4 occurred on 6 years (2006-2011) over South Western US seismic area. Results of such a study (with a rate of false positive of 35%) give an idea on the possible relevance of RST based TIR surveys in the framework of an operational, multi-parametric system for time-Dependent Assessment of Seismic Hazard (t-DASH). In this paper all the data available from the new GOES-W satellite (in orbit in between 2010 and 2014) have been analysed by the same way in the case of the earthquake occurred on 24 August 2014 (M=6) over Napa valley (California). The results presented in this paper, even if still preliminary, seem to confirm the significance of RST based TIR survey in a t-DASH perspective. It should however mentioned, that such an approach (even if not devoted to be used for short-term Earthquake Forecast outside a multiparametric t-DASH system), when compared with whatever traditional OEF (Operational Earthquake Forecast) method (like the one abandoned ten years ago in US but recently re-proposed for Italy) seems already to gives forecast reliabilities of orders of magnitude greater.

  3. Seismic Disaster Mitigation in Urban Area by using Building Vibration Observation of Weak Earthquake Ground Motion: an Approach of the IT Kyoshin Seismometer for Buildings

    NASA Astrophysics Data System (ADS)

    Takano, K.; Ito, T.

    2010-12-01

    There are a lot of buildings which is not experienced severe earthquakes in urban area. In Hanshin-Awaji (Kobe) Earthquake, it was presumed that 80 percent or more of the person was dead immediately after the earthquake by building collapse. Also in Haiti, a lot of buildings deprived of the life of persons. In order to prevent the earthquake damage of urban area, it is the most effective to make the building earthquake-proof. However, there are still a lot of buildings not made earthquake-proof in Japan though 15 years passed since Kobe Earthquake. In order to promote making of the building earthquake-proof, various approaches such as visualization of seismic hazard, education of disaster prevention and legal system for promotion are needed. We have developed the IT Kyoshin(strong motion) Seismometer for Building which is the observation system of the usual weak earthquake ground motion by installing a lot of acceleration sensors in building, and have been setting it up in some buildings of the University of Tokyo. We have also developed the visualization tool that can reproduce the building vibration during earthquake from the observed data. By this tool, we can successfully show where is more shaking in the building or what is the feature of building vibration easily. Such information contributes to not only promotion of making building earthquake-proof but also promotion of disaster prevention action such as fixation of bookshelf, making the safety area in building, etc. In addition, we proposed a concrete technique of the health investigation of buildings by using weak earthquake ground motion. Because there are 20 to 30 felt earthquakes in year in Tokyo area, it is possible to observe these building vibrations by using weak earthquake ground motions. In addition, we have developed the high sensitive ITK sensor which can observe from the microtremor to the felt earthquake in the place without the felt earthquake either.

  4. The study of recent seismicity in the aftershock area of Neftegorsk earthquake using waveform cross correlation

    NASA Astrophysics Data System (ADS)

    Kitov, Ivan; Turuntaev, Sergey; Konovalov, Alexei; Stepnov, Andrey

    2016-04-01

    Unusually long duration of seismic activity (more than 20 years) was observed in the aftershock area of the 1995 Neftegorsk, Sakhalin, Russia catastrophic earthquake (Ms=7.6). To study the phenomena, we have processed seismic data from 130 events occurred within that area as measured between 2006 and 2015. In order to improve the accuracy of relative location and magnitude estimation of these events we have applied new techniques based on waveform cross correlation. We use 7 three-component (3-C) seismic stations which detected most of these events. Three-component waveform templates were prepared for these stations from those events which had signals with SNR>5 at vertical channels. The events with 3 and more templates are used as master-events for waveform cross correlation. Overall, the re-estimated location and magnitudes demonstrate higher precisions and are used for the statistical analysis and numerical modelling of seismo-tectonic regime within the studied zone.

  5. Association of earthquakes and faults in the San Francisco Bay area using Bayesian inference

    USGS Publications Warehouse

    Wesson, R.L.; Bakun, W.H.; Perkins, D.M.

    2003-01-01

    Bayesian inference provides a method to use seismic intensity data or instrumental locations, together with geologic and seismologic data, to make quantitative estimates of the probabilities that specific past earthquakes are associated with specific faults. Probability density functions are constructed for the location of each earthquake, and these are combined with prior probabilities through Bayes' theorem to estimate the probability that an earthquake is associated with a specific fault. Results using this method are presented here for large, preinstrumental, historical earthquakes and for recent earthquakes with instrumental locations in the San Francisco Bay region. The probabilities for individual earthquakes can be summed to construct a probabilistic frequency-magnitude relationship for a fault segment. Other applications of the technique include the estimation of the probability of background earthquakes, that is, earthquakes not associated with known or considered faults, and the estimation of the fraction of the total seismic moment associated with earthquakes less than the characteristic magnitude. Results for the San Francisco Bay region suggest that potentially damaging earthquakes with magnitudes less than the characteristic magnitudes should be expected. Comparisons of earthquake locations and the surface traces of active faults as determined from geologic data show significant disparities, indicating that a complete understanding of the relationship between earthquakes and faults remains elusive.

  6. Pre-earthquake assessment and recovery planning for the regional transportation system in the San Francisco Bay area

    SciTech Connect

    Perkins, J.B.

    1995-12-31

    In May 1995, ABAG began a cooperative project with Caltrans District 4 to perform a vulnerability analysis of the regional transportation system in the San Francisco Bay Area. This assessment will be used for pre-earthquake planning to speed the recovery process for the transportation system, including both freeways and local roads. The project is using geographic information system (GIS) technology and computer simulation models to assist in the vulnerability analyses, assessment of hazard mitigation strategies, and pre-earthquake planning activities. It is expected that this project will result in improving post-earthquake short-term emergency response as well as in shortening the time for long-term recovery. In addition, this innovative and timely approach should be applicable to other large metropolitan areas of the state, as well as to other metropolitan areas in the nation.

  7. The Structure of a BamA-BamD Fusion Illuminates the Architecture of the β-Barrel Assembly Machine Core.

    PubMed

    Bergal, Hans Thor; Hopkins, Alex Hunt; Metzner, Sandra Ines; Sousa, Marcelo Carlos

    2016-02-01

    The β-barrel assembly machine (BAM) mediates folding and insertion of integral β-barrel outer membrane proteins (OMPs) in Gram-negative bacteria. Of the five BAM subunits, only BamA and BamD are essential for cell viability. Here we present the crystal structure of a fusion between BamA POTRA4-5 and BamD from Rhodothermus marinus. The POTRA5 domain binds BamD between its tetratricopeptide repeats 3 and 4. The interface structural elements are conserved in the Escherichia coli proteins, which allowed structure validation by mutagenesis and disulfide crosslinking in E. coli. Furthermore, the interface is consistent with previously reported mutations that impair BamA-BamD binding. The structure serves as a linchpin to generate a BAM model where POTRA domains and BamD form an elongated periplasmic ring adjacent to the membrane with a central cavity approximately 30 × 60 Å wide. We propose that nascent OMPs bind this periplasmic ring prior to insertion and folding by BAM.

  8. Strong near-trench locking and its temporal change in the rupture area of the 2011 Tohoku-oki earthquake estimated from cumulative slip and slip vectors of interplate earthquakes

    NASA Astrophysics Data System (ADS)

    Uchida, N.; Hasegawa, A.; Matsuzawa, T.

    2012-12-01

    The 2011 Mw 9.0 Tohoku-oki earthquake is characterized by large near-trench slip that excited disastrous Tsunami. It is of great importance to estimate the coupling state near the trench to understand temporal evolution of interplate coupling near the earthquake source as well as for the assessment of tsunami risk along the trench. However, the coupling states at the near trench areas far from the land are usually not well constrained. The cumulative offset of small repeating earthquakes reflects the in situ slip history on a fault and the slip vectors of interplate earthquakes reflect heterogeneous distribution of coupling on the plate boundary. In this study, we use the repeating earthquake and slip vector data to estimate spatio-temporal change in slip and coupling in and around the source area of the Tohoku-oki earthquake near the Japan trench. The repeating earthquake data for 27 years before the Tohoku-oki earthquake show absence of repeating earthquake groups in the large-coseismic-slip area and low and variable slip rates in the moderate-coseismic-slip region surrounding the large-slip. The absence of repeaters itself could have been explained by both models with very weak coupling and very strong coupling. However, the rotation of slip vectors of interplate earthquakes at the deeper extension of the large-coseismic-slip suggest the plate boundary was locked in the near-trench area before the earthquake, which is consistent with the estimation by Hasegawa et al. (2012) based on stress tensor analysis of the upper plate events near the trench axis. The repeating earthquake data, on the other hand, show small but distinct increases in the slip rate in the 3-5 years before the earthquake near the area of large coseismic slip suggesting preseismic unfastening of the locked area in the last stage of the earthquake cycle. After the Tohoku-oki earthquake, repeating earthquakes activity in the main rupture area disappeared almost completely and slip vectors of

  9. Real-time earthquake alert system for the greater San Francisco Bay Area: a prototype design to address operational issues

    SciTech Connect

    Harben, P.E.; Jarpe, S.; Hunter, S.

    1996-05-29

    This paper describes a prototype for this EAS (real time) in the Bay area. Approach is pragmatic, attempting to establish a prototype system at a low cost and quickly. A real-time warning system can protect the public and mitigate earthquake damage. The proposed system is a distributed network of real-time strong-motion monitoring stations that telemetered data in real time to a central analysis facility which could transmit earthquake parameter information to an area before elastic wave energy arrived. Upgrades and issues that should be resolved before an operational EAS can be established, are listed.

  10. Real-Time GPS Monitoring for Earthquake Rapid Assessment in the San Francisco Bay Area

    NASA Astrophysics Data System (ADS)

    Guillemot, C.; Langbein, J. O.; Murray, J. R.

    2012-12-01

    The U.S. Geological Survey Earthquake Science Center has deployed a network of eight real-time Global Positioning System (GPS) stations in the San Francisco Bay area and is implementing software applications to continuously evaluate the status of the deformation within the network. Real-time monitoring of the station positions is expected to provide valuable information for rapidly estimating source parameters should a large earthquake occur in the San Francisco Bay area. Because earthquake response applications require robust data access, as a first step we have developed a suite of web-based applications which are now routinely used to monitor the network's operational status and data streaming performance. The web tools provide continuously updated displays of important telemetry parameters such as data latency and receive rates, as well as source voltage and temperature information within each instrument enclosure. Automated software on the backend uses the streaming performance data to mitigate the impact of outages, radio interference and bandwidth congestion on deformation monitoring operations. A separate set of software applications manages the recovery of lost data due to faulty communication links. Displacement estimates are computed in real-time for various combinations of USGS, Plate Boundary Observatory (PBO) and Bay Area Regional Deformation (BARD) network stations. We are currently comparing results from two software packages (one commercial and one open-source) used to process 1-Hz data on the fly and produce estimates of differential positions. The continuous monitoring of telemetry makes it possible to tune the network to minimize the impact of transient interruptions of the data flow, from one or more stations, on the estimated positions. Ongoing work is focused on using data streaming performance history to optimize the quality of the position, reduce drift and outliers by switching to the best set of stations within the network, and

  11. Non-double-couple earthquake mechanisms at the Geysers geothermal area, California

    USGS Publications Warehouse

    Ross, A.; Foulger, G.R.; Julian, B.R.

    1996-01-01

    Inverting P- and S-wave polarities and P:SH amplitude ratios using linear programming methods suggests that about 20% of earthquakes at The Geysers geothermal area have significantly non-double-couple focal mechanisms, with explosive volumetric components as large as 33% of the seismic moment. This conclusion contrasts with those of earlier studies, which interpreted data in terms of double couples. The non-double-couple mechanisms are consistent with combined shear and tensile faulting, possibly caused by industrial water injection. Implosive mechanisms, which might be expected because of rapid steam withdrawal, have not been found. Significant compensated-linear-vector-dipole (CLVD) components in some mechanisms may indicate rapid fluid flow accompanying crack opening. Copyright 1996 by the American Geophysical Union.

  12. The 'terrifying' Seattle/Olympia earthquake: a learning experience for area hospitals about disaster plans.

    PubMed

    2001-04-01

    A 6.8-magnitude earthquake that struck the Seattle/Olympia area about an hour before lunchtime on Wednesday, February 28, caused an estimated $2 billion in damage but resulted in only one death. The quake was centered near Washington's state capital, Olympia, about 50 miles from Seattle. Scientists attribute the relatively small amount of damage to the fact that the quake was a deep one centered about 30 miles below the earth's surface. Experts also credit modern building codes, which require new buildings to be quake-resistant, and the retrofitting of older buildings to resist quakes for the lack of damage and casualties (less than 400 injuries). Hospitals in the region escaped serious damage and emergency rooms received relatively few casualties. However, in carrying out disaster plans, security and safety officials uncovered a number of problems that could have had serious impact in another emergency situation.

  13. Crustal structures in the area of the 2008 Sichuan earthquake from seismologic and gravimetric data

    NASA Astrophysics Data System (ADS)

    Robert, A.; Zhu, J.; Vergne, J.; Cattin, R.; Chan, L. S.; Wittlinger, G.; Herquel, G.; de Sigoyer, J.; Pubellier, M.; Zhu, L. D.

    2010-08-01

    The 12 May 2008 the Sichuan earthquake was one of the worst natural disasters in China. Here, we present a detailed picture of the epicentral area inferred geophysical data. Based on the analysis of teleseismic data acquired by a dense seismic network, we highlight an abrupt 20 km Moho offset between the Sichuan Basin and the Tibetan plateau and a horizontal discontinuity at ˜ 15 km depth, which may connect with the ruptured zone of the 2008 event. We obtain low mean crustal velocity ratios, which suggest the absence of a thick and extensive zone of partial melt within the crust beneath the eastern part of the Songpan-Garze Terrane. All our data support the idea that the Longmen Shan range mark a zone of active strain localization due to the rigid Yangtze craton resisting eastward displacement of the Tibetan Plateau.

  14. Geographical Information Analysis of Tsunami Flooded Area by the Great East Japan Earthquake Using Mobile Mapping System

    NASA Astrophysics Data System (ADS)

    Koarai, M.; Okatani, T.; Nakano, T.; Nakamura, T.; Hasegawa, M.

    2012-07-01

    The great earthquake occurred in Tohoku District, Japan on 11th March, 2011. This earthquake is named "the 2011 off the Pacific coast of Tohoku Earthquake", and the damage by this earthquake is named "the Great East Japan Earthquake". About twenty thousand people were killed or lost by the tsunami of this earthquake, and large area was flooded and a large number of buildings were destroyed by the tsunami. The Geospatial Information Authority of Japan (GSI) has provided the data of tsunami flooded area interpreted from aerial photos taken just after the great earthquake. This is fundamental data of tsunami damage and very useful for consideration of reconstruction planning of tsunami damaged area. The authors analyzed the relationship among land use, landform classification, DEMs data flooded depth of the tsunami flooded area by the Great East Japan Earthquake in the Sendai Plain using GIS. Land use data is 100 meter grid data of National Land Information Data by the Ministry of Land, Infrastructure, Transportation and Tourism (MLIT). Landform classification data is vector data of Land Condition Map produced by GSI. DEMs data are 5 meters grid data measured with LiDAR by GSI after earthquake. Especially, the authors noticed the relationship between tsunami hazard damage and flooded depth. The authors divided tsunami damage into three categories by interpreting aerial photos; first is the completely destroyed area where almost wooden buildings were lost, second is the heavily damaged area where a large number of houses were destroyed by the tsunami, and third is the flooded only area where houses were less destroyed. The flooded depth was measured by photogrammetric method using digital image taken by Mobile Mapping System (MMS). The result of these geographic analyses show the distribution of tsunami damage level is as follows: 1) The completely destroyed area was located within 1km area from the coastline, flooded depth of this area is over 4m, and no relationship

  15. High-resolution local earthquake tomography of the southern Dead Sea area

    NASA Astrophysics Data System (ADS)

    Braeuer, B.; Asch, Guenter; Hofstetter, R.; Haberland, Ch.; Jaser, D.; El-Kelani, R.; Weber, M.

    2012-12-01

    Local earthquake data from a dense temporary seismological network in the southern Dead Sea area have been analysed within the project DESIRE (Dead Sea Integrated Research Project). Local earthquakes are used for the first precise image of the distribution of the P-wave 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 model for the vP and vP/vS distribution. Since the study area is at first-order 2-D, a gradual approach was chosen, which compromised a 2-D inversion followed by a 3-D inversion. The sedimentary basin fill is clearly imaged through high vP/vS ratios and low vP. The basin fill shows an asymmetric structure with average depth of 7 km at the western boundary and depth between 10 and 14 km at the eastern boundary. This asymmetry is reflected by the vertical strike-slip eastern border fault, and the normal faulting at the western boundary, caused by the transtensional deformation within the last 5 Myr. Within the basin fill the Lisan salt diapir is imaged through low vP/vS ratios, reflecting its low fluid content. The extensions were determined to 12 km in E-W and 17 km in N-S direction while its depth is 5-6 km. The thickness of the pre-basin sediments below the basin fill cannot be derived from the tomography data—it is estimated to less than 3 km from former investigations. Below the basin, down to 18 km depth very low P-wave velocities and low vP/vS ratios are observed—most likely caused by fluids from the surrounding crust or the upper mantle.

  16. Predicted Liquefaction in the Greater Oakland and Northern Santa Clara Valley Areas for a Repeat of the 1868 Hayward Earthquake

    NASA Astrophysics Data System (ADS)

    Holzer, T. L.; Noce, T. E.; Bennett, M. J.

    2008-12-01

    Probabilities of surface manifestations of liquefaction due to a repeat of the 1868 (M6.7-7.0) earthquake on the southern segment of the Hayward Fault were calculated for two areas along the margin of San Francisco Bay, California: greater Oakland and the northern Santa Clara Valley. Liquefaction is predicted to be more common in the greater Oakland area than in the northern Santa Clara Valley owing to the presence of 57 km2 of susceptible sandy artificial fill. Most of the fills were placed into San Francisco Bay during the first half of the 20th century to build military bases, port facilities, and shoreline communities like Alameda and Bay Farm Island. Probabilities of liquefaction in the area underlain by this sandy artificial fill range from 0.2 to ~0.5 for a M7.0 earthquake, and decrease to 0.1 to ~0.4 for a M6.7 earthquake. In the greater Oakland area, liquefaction probabilities generally are less than 0.05 for Holocene alluvial fan deposits, which underlie most of the remaining flat-lying urban area. In the northern Santa Clara Valley for a M7.0 earthquake on the Hayward Fault and an assumed water-table depth of 1.5 m (the historically shallowest water level), liquefaction probabilities range from 0.1 to 0.2 along Coyote and Guadalupe Creeks, but are less than 0.05 elsewhere. For a M6.7 earthquake, probabilities are greater than 0.1 along Coyote Creek but decrease along Guadalupe Creek to less than 0.1. Areas with high probabilities in the Santa Clara Valley are underlain by latest Holocene alluvial fan levee deposits where liquefaction and lateral spreading occurred during large earthquakes in 1868 and 1906. The liquefaction scenario maps were created with ArcGIS ModelBuilder. Peak ground accelerations first were computed with the new Boore and Atkinson NGA attenuation relation (2008, Earthquake Spectra, 24:1, p. 99-138), using VS30 to account for local site response. Spatial liquefaction probabilities were then estimated using the predicted ground motions

  17. Moho depth retrieval from waveforms of micro-earthquakes in the West Bohemia/Vogtland seismoactive area

    NASA Astrophysics Data System (ADS)

    Hrubcova, P.; Vavrycuk, V.; Bouskova, A.

    2011-12-01

    The West Bohemia/Vogtland region is the area of an increased geodynamic activity manifested by numerous mineral springs and CO2 emissions located at the intersection of fault zones. The seismicity is characterized by a reoccurrence of intraplate earthquake swarms with the local magnitude mostly less than 4. Knowledge of a detailed crustal structure in this area is essential for all advanced studies of seismicity and focal parameters of the micro-earthquakes. In our study, we concentrate on the velocity model and Moho depth retrieval using waveforms of local micro-earthquakes that occurred during the 2008 swarm and were observed at the WEBNET seismic network stations. The waveforms typically display dominant direct P and S waves followed by converted and reflected waves secondarily generated at shallow and deep subsurface structure. Apart from the velocity structure and the source-receiver geometry the waveforms are significantly affected by focal mechanisms of the earthquakes Therefore, the waveforms are processed separately for clusters of earthquakes with a similar mechanism. Applying the waveform cross-correlation for the P and S waves we calculate the accurate time shifts of seismograms. The aligned seismograms are stacked to extract the Moho reflected PP and SS waves. The PP and SS arrival times are inverted for laterally varying depth of the Moho using the ray-tracing approach. The retrieved model is verified using modelling of the full waveforms calculated by the discrete wavenumber method.

  18. Long-period ocean-bottom motions in the source areas of large subduction earthquakes.

    PubMed

    Nakamura, Takeshi; Takenaka, Hiroshi; Okamoto, Taro; Ohori, Michihiro; Tsuboi, Seiji

    2015-01-01

    Long-period ground motions in plain and basin areas on land can cause large-scale, severe damage to structures and buildings and have been widely investigated for disaster prevention and mitigation. However, such motions in ocean-bottom areas are poorly studied because of their relative insignificance in uninhabited areas and the lack of ocean-bottom strong-motion data. Here, we report on evidence for the development of long-period (10-20 s) motions using deep ocean-bottom data. The waveforms and spectrograms demonstrate prolonged and amplified motions that are inconsistent with attenuation patterns of ground motions on land. Simulated waveforms reproducing observed ocean-bottom data demonstrate substantial contributions of thick low-velocity sediment layers to development of these motions. This development, which could affect magnitude estimates and finite fault slip modelling because of its critical period ranges on their estimations, may be common in the source areas of subduction earthquakes where thick, low-velocity sediment layers are present.

  19. Long-period ocean-bottom motions in the source areas of large subduction earthquakes

    PubMed Central

    Nakamura, Takeshi; Takenaka, Hiroshi; Okamoto, Taro; Ohori, Michihiro; Tsuboi, Seiji

    2015-01-01

    Long-period ground motions in plain and basin areas on land can cause large-scale, severe damage to structures and buildings and have been widely investigated for disaster prevention and mitigation. However, such motions in ocean-bottom areas are poorly studied because of their relative insignificance in uninhabited areas and the lack of ocean-bottom strong-motion data. Here, we report on evidence for the development of long-period (10–20 s) motions using deep ocean-bottom data. The waveforms and spectrograms demonstrate prolonged and amplified motions that are inconsistent with attenuation patterns of ground motions on land. Simulated waveforms reproducing observed ocean-bottom data demonstrate substantial contributions of thick low-velocity sediment layers to development of these motions. This development, which could affect magnitude estimates and finite fault slip modelling because of its critical period ranges on their estimations, may be common in the source areas of subduction earthquakes where thick, low-velocity sediment layers are present. PMID:26617193

  20. Reconnaissance engineering geology of the Metlakatla area, Annette Island, Alaska, with emphasis on evaluation of earthquakes and other geologic hazards

    USGS Publications Warehouse

    Yehle, Lynn A.

    1977-01-01

    A program to study the engineering geology of most larger Alaska coastal communities and to evaluate their earthquake and other geologic hazards was started following the 1964 Alaska earthquake; this report about the Metlakatla area, Annette Island, is a product of that program. Field-study methods were of a reconnaissance nature, and thus the interpretations in the report are tentative. Landscape of the Metlakatla Peninsula, on which the city of Metlakatla is located, is characterized by a muskeg-covered terrane of very low relief. In contrast, most of the rest of Annette Island is composed of mountainous terrane with steep valleys and numerous lakes. During the Pleistocene Epoch the Metlakatla area was presumably covered by ice several times; glaciers smoothed the present Metlakatla Peninsula and deeply eroded valleys on the rest. of Annette Island. The last major deglaciation was completed probably before 10,000 years ago. Rebound of the earth's crust, believed to be related to glacial melting, has caused land emergence at Metlakatla of at least 50 ft (15 m) and probably more than 200 ft (61 m) relative to present sea level. Bedrock in the Metlakatla area is composed chiefly of hard metamorphic rocks: greenschist and greenstone with minor hornfels and schist. Strike and dip of beds are generally variable and minor offsets are common. Bedrock is of late Paleozoic to early Mesozoic age. Six types of surficial geologic materials of Quaternary age were recognized: firm diamicton, emerged shore, modern shore and delta, and alluvial deposits, very soft muskeg and other organic deposits, and firm to soft artificial fill. A combination map unit is composed of bedrock or diamicton. Geologic structure in southeastern Alaska is complex because, since at least early Paleozoic time, there have been several cycles of tectonic deformation that affected different parts of the region. Southeastern Alaska is transected by numerous faults and possible faults that attest to major

  1. Statistical analysis of seismicity rate change in the Tokyo Metropolitan area due to the 2011 Tohoku Earthquake

    NASA Astrophysics Data System (ADS)

    Ishibe, T.; Sakai, S.; Shimazaki, K.; Satake, K.; Tsuruoka, H.; Nakagawa, S.; Hirata, N.

    2012-12-01

    We examined a relationship between the Coulomb Failure Function (ΔCFF) due to the Tohoku earthquake (March 11, 2011; MJMA 9.0) and the seismicity rate change in Tokyo Metropolitan area following March 2011. Because of large variation in focal mechanism in the Kanto region, the receiver faults for the ΔCFF were assumed to be two nodal planes of small (M ≥ 2.0) earthquakes which occurred before and after the Tohoku earthquake. The seismicity rate changes, particularly the rate increase, are well explained by ΔCFF due to the gigantic thrusting, while some other possible factors (e.g., dynamic stress changes, excess of fluid dehydration) may also contribute the rate changes. Among 30,746 previous events provided by the National Research Institute for Earth Science and Disaster Prevention (M ≥ 2.0, July 1979 - July 2003), we used as receiver faults, almost 16,000 events indicate significant increase in ΔCFF, while about 8,000 events show significant decrease. Positive ΔCFF predicts seismicity rate increase in southwestern Ibaraki and northern Chiba prefectures where intermediate-depth earthquakes occur, and in shallow crust of the Izu-Oshima and Hakone regions. In these regions, seismicity rates significantly increased after the Tohoku earthquake. The seismicity has increased since March 2011 with respect to the Epidemic Type of Aftershock Sequence (ETAS) model (Ogata, 1988), indicating that the rate change was due to the stress increase by the Tohoku earthquake. The activated seismicity in the Izu and Hakone regions rapidly decayed following the Omori-Utsu formula, while the increased rate of seismicity in the southwestern Ibaraki and northern Chiba prefectures is still continuing. We also calculated ΔCFF due to the 2011 Tohoku earthquake for the focal mechanism solutions of earthquakes between April 2008 and October 2011 recorded on the Metropolitan Seismic Observation network (MeSO-net). The ΔCFF values for the earthquakes after March 2011 show more

  2. The large earthquake of 8 August 1303 in Crete: seismic scenario and tsunami in the Mediterranean area

    NASA Astrophysics Data System (ADS)

    Guidoboni, Emanuela; Comastri, Alberto

    By conducting a historical review of this large seismic event in the Mediterranean, it has been possible to identify both the epicentral area and the area in which its effects were principally felt. Ever since the nineteenth century, the seismological tradition has offered a variety of partial interpretations of the earthquake, depending on whether the main sources used were Arabic, Greek or Latin texts. Our systematic research has involved the analysis not only of Arab, Byzantine and Italian chronicle sources, but also and in particular of a large number of never previously used official and public authority documents, preserved in Venice in the State Archive, in the Marciana National Library and in the Library of the Museo Civico Correr. As a result, it has been possible to establish not only chronological parameters for the earthquake (they were previously uncertain) but also its overall effects (epicentral area in Crete, Imax XI MCS). Sources containing information in 41 affected localities and areas were identified. The earthquake also gave rise to a large tsunami, which scholars have seen as having certain interesting elements in common with that of 21 July 365, whose epicentre was also in Crete. As regards methodology, this research made it clear that knowledge of large historical earthquakes in the Mediterranean is dependent upon developing specialised research and going beyond the territorial limits of current national catalogues.

  3. Prominent reflector beneath around the segmentation boundary between Tonankai-Nankai earthquake area

    NASA Astrophysics Data System (ADS)

    Nakanishi, A.; Shimomura, N.; Fujie, G.; Kodaira, S.; Obana, K.; Takahashi, T.; Yamamoto, Y.; Yamashita, M.; Takahashi, N.; Kaneda, Y.; Mochizuki, K.; Kato, A.; Iidaka, T.; Kurashimo, E.; Shinohara, M.; Takeda, T.; Shiomi, K.

    2013-12-01

    In the Nankai Trough subduction seismogenic zone, the Nankai and Tonankai earthquakes had often occurred simultaneously, and caused a great event. In most cases, first break of such large events of Nankai Trough usually begins from southwest off the Kii Peninsula so far. The idea of split Philippine Sea plate between the Kii Peninsula and the Shikoku Island, which explains seismicity, tectonic background, receiver function image and historical plate motion, was previously suggested. Moreover, between the Kii Peninsula and the Shikoku Island, there is a gap of deep low-frequency events observed in the belt-like zone along the strike of the subducting Philippine Sea plate. In 2010 and 2011, we conducted the large-scale high-resolution wide-angle and reflection (MCS) seismic study, and long-term observation from off Shikoku and Kii Peninsula. Marine active source seismic data have been acquired along grid two-dimensional profiles having the total length of ~800km/year. A three-dimensional seismic tomography using active and passive seismic data observed both land and ocean bottom stations have been also performed. From those data, we found a possible prominent reflector imaged in the offshore side in the Kii channel at the depth of ~18km. The velocity just beneath the reflector cannot be determined due to the lack of ray paths. Based of the amplitude information, we interpret the reflector as the forearc Moho based on the velocity gap (from ~6.4km/s to ~7.4km/s). However, the reflector is shallower than the forearc Moho of other area along the Nankai Trough. Similar reflectors are recognized along other seismic profiles around the Kii channel. In this presentation, we will show the result of structure analysis to understand the peculiar structure including the prominent reflector around the Kii channel. Relation between the structure and the existence of the segmentation of the Nankai megathrust earthquake or seismic gap of the deep low-frequency events will be also

  4. Attenuation tomography in the rupture area of the 2010 M8.8 Maule, Chile, earthquake

    NASA Astrophysics Data System (ADS)

    Heather-Smith, Helen; Rietbrock, Andreas

    2016-04-01

    In recent years several seismological studies have developed a detailed image of the megathrust interface between the subducting Nazca plate and and the overriding South American plate in the rupture area of the 2010 M8.8 Maule, Chile, earthquake. Hicks et al. (2014) have published a high resolution 3D seismic tomography model and characterised the different regimes acting along the interface based on their seismic properties. A more detailed study by Moreno et al. (2014) showed that the seismic Vp/Vs ratio and inter-seismic locking determined from GPS measurements are correlated. Together these observations open up the possibility to map the rupture potential of possible future earthquakes, although the underlying processes are yet not fully understood and a more in depth analysis of other physical properties is needed. 3D seismic attenuation structure as well as seismic stress-drop distribution based on the aftershock seismicity are providing independent data sets to better constrain the physical processes acting along the subduction zone interface. As seismic attenuation is particularly sensitive to fluid saturation it opens up the possibility to study more directly the influence of fluids on aftershock activity as compared to standard velocity tomography studies. Based on our event catalogue of approximately 30,000 aftershocks we are currently selecting the most appropriate data set for the staggered 3D attenuation tomography. The inverted attenuation model will then be used to calculate seismic stress drop values for the complete aftershock catalogue. We will present our preliminary 3D attenuation model together with our stress drop estimates and compare our finding to the 3D velocity structure and slip distribution.

  5. Engineering and socioeconomic impacts of earthquakes: An analysis of electricity lifeline disruptions in the New Madrid area

    SciTech Connect

    Shinozuka, M.; Rose, A.; Eguchi, R.T.

    1998-12-31

    This monograph examines the potential effects of a repeat of the New Madrid earthquake to the metropolitan Memphis area. The authors developed a case study of the impact of such an event to the electric power system, and analyzed how this disruption would affect society. In nine chapters and 189 pages, the book traces the impacts of catastrophic earthquakes through a curtailment of utility lifeline services to its host regional economy and beyond. the monographs` chapters include: Modeling the Memphis economy; seismic performance of electric power systems; spatial analysis techniques for linking physical damage to economic functions; earthquake vulnerability and emergency preparedness among businesses; direct economic impacts; regional economic impacts; socioeconomic and interregional impacts; lifeline risk reduction; and public policy formulation and implementation.

  6. [Carbon source metabolic diversity of soil microbial community under different climate types in the area affected by Wenchuan earthquake].

    PubMed

    Zhang, Guang-Shuai; Lin, Yong-Ming; Ma, Rui-Feng; Deng, Hao-Jun; Du, Kun; Wu, Cheng-Zhen; Hong, Wei

    2015-02-01

    The MS8.0 Wenchuan earthquake in 2008 led to huge damage to land covers in northwest Sichuan, one of the critical fragile eco-regions in China which can be divided into Semi-arid dry hot climate zone (SDHC) and Subtropical humid monsoon climate zone (SHMC). Using the method of Bilog-ECO-microplate technique, this paper aimed to determine the functional diversity of soil microbial community in the earthquake-affected areas which can be divided into undamaged area (U), recover area (R) and damaged area without recovery (D) under different climate types, in order to provide scientific basis for ecological recovery. The results indicated that the average-well-color-development (AWCD) in undamaged area and recovery area showed SDHC > SHMC, which was contrary to the AWCD in the damaged area without recovery. The AWCD of damaged area without recovery was the lowest in both climate zones. The number of carbon source utilization types of soil microbial in SHMC zone was significantly higher than that in SDHC zone. The carbon source utilization types in both climate zones presented a trend of recover area > undamaged area > damaged area without recovery. The carbon source metabolic diversity characteristic of soil microbial community was significantly different in different climate zones. The diversity index and evenness index both showed a ranking of undamaged area > recover area > damaged area without recovery. In addition, the recovery area had the highest richness index. The soil microbial carbon sources metabolism characteristic was affected by soil nutrient, aboveground vegetation biomass and vegetation coverage to some extent. In conclusion, earthquake and its secondary disasters influenced the carbon source metabolic diversity characteristic of soil microbial community mainly through the change of aboveground vegetation and soil environmental factors.

  7. The tsunami source area of the 2003 Tokachi-oki earthquake estimated from tsunami travel times and its relationship to the 1952 Tokachi-oki earthquake

    USGS Publications Warehouse

    Hirata, K.; Tanioka, Y.; Satake, K.; Yamaki, S.; Geist, E.L.

    2004-01-01

    We estimate the tsunami source area of the 2003 Tokachi-oki earthquake (Mw 8.0) from observed tsunami travel times at 17 Japanese tide gauge stations. The estimated tsunami source area (???1.4 ?? 104 km2) coincides with the western-half of the ocean-bottom deformation area (???2.52 ?? 104 km2) of the 1952 Tokachi-oki earthquake (Mw 8.1), previously inferred from tsunami waveform inversion. This suggests that the 2003 event ruptured only the western-half of the 1952 rupture extent. Geographical distribution of the maximum tsunami heights in 2003 differs significantly from that of the 1952 tsunami, supporting this hypothesis. Analysis of first-peak tsunami travel times indicates that a major uplift of the ocean-bottom occurred approximately 30 km to the NNW of the mainshock epicenter, just above a major asperity inferred from seismic waveform inversion. Copyright ?? The Society of Geomagnetism and Earth, Planetary and Space Sciences (SGEPSS); The Seismological Society of Japan; The Volcanological Society of Japan; The Geodetic Society of Japan; The Japanese Society for Planetary Sciences.

  8. Effects of the earthquake of March 27, 1964 in the Copper River Basin area, Alaska: Chapter E in The Alaska earthquake, March 27, 1964: regional effects

    USGS Publications Warehouse

    Ferrians, Oscar J.

    1966-01-01

    The Copper River Basin area is in south-central Alaska and covers 17,800 square miles. It includes most of the Copper River Basin and parts of the surrounding Alaska Range and the Talkeetna, Chugach, and Wrangell Mountains. On March 27, 1964, shortly after 5:36 p.m. Alaska standard time, a great earthquake having a Richter magnitude of about 8.5 struck south-central Alaska. Computations by the U.S. Coast and Geodetic Survey place the epicenter of the main shock at lat 61.1° N. and long 147.7° W., and the hypocenter, or actual point of origin, from 20 to 50 kilometers below the surface. The epicenter is near the western shore of Unakwik Inlet in northern Prince William Sound; it is 30 miles from the closest point within the area of study and 180 miles from the farthest point. Releveling data obtained in 1964 after the earthquake indicates that broad areas of south-central Alaska were warped by uplift and subsidence. The configuration of these areas generally parallels the trend of the major tectonic elements of the region. Presumably a large part of this change took place during and immediately after the 1964 earthquake. The water level in several wells in the area lowered appreciably, and the water in many became turbid; generally, however, within a few days after the earthquake the water level returned to normal and the suspended sediment settled out. Newspaper reports that the Copper River was completely dammed and Tazlina Lake drained proved erroneous. The ice on most lakes was cracked, especially around the margins of the lakes where floating ice broke free from the ice frozen to the shore. Ice on Tazlina, Klutina, and Tonsina Lakes was intensely fractured by waves generated by sublacustrine landslides off the fronts of deltas. These waves stranded large blocks of ice above water level along the shores. River ice was generally cracked in the southern half of the area and was locally cracked in the northern half. In the area of study, the majority of the

  9. Stress field in the Northern Rhine area, Central Europe, from earthquake fault plane solutions

    NASA Astrophysics Data System (ADS)

    Hinzen, Klaus-G.

    2003-12-01

    Fault plane solutions (FPS) from 110 earthquakes in the northern Rhine area with local magnitudes, ranging from 1.0 to 6.1, and occurring between 1976 and 2002 are determined. FPS are retrieved from P-wave first motions using a grid search approach allowing a detailed exploration of the parameter space. The influence of the 1D velocity model on take-off angles and resulting FPS is examined. All events were relocated with a recently developed minimum 1D model of the velocity structure [J. Geophys. Res. (2003)]. Rose diagrams of the orientation of P, T and B axes show a clear preference of trends of P and T axes at N292°E and N27°E, respectively. The majority of B axes trend in northerly directions. Plunges of P and T axes are mostly around 45° while most B axes are subhorizontal. The main direction of the maximum horizontal stress directly inferred from the fault plane solutions is N118°E. To calculate the orientations of the principal stress axes and the shape of the stress tensor, the inversion method of Gephard and Forsyth [J. Geophys. Res. 89 (1984) 9305] was applied to the whole data set and to several subsets of data. The subsets were formed by grouping events from various geological and tectonic areas and by grouping events into different depth ranges. The subset areas include the Lower Rhine Embayment, the Rhenish Massif, the middle Rhine area, the Neuwied Basin and the area known as the Stavelot-Venn Massif. Inversion of the entire data set shows some ambiguity between a strike-slip and extensional stress regime, with a vertical axis for the medium principal stress and a trend of N305°E and N35°E for the σ1 and σ3 axis, respectively, as the best fitting tensor. Earthquakes from the Lower Rhine Embayment and, to some degree, from the middle Rhine area indicate an extensional stress regime. In the Lower Rhine Embayment, plunge and trend of the σ1 axis are 76° and N162°E and for the σ3 axis 7° and N42°E. The best fitting solution for the area of

  10. Quasi-periodic slow slip events in the afterslip area of the 1996 Hyuga-nada earthquakes, Japan

    NASA Astrophysics Data System (ADS)

    Yarai, Hiroshi; Ozawa, Shinzaburo

    2013-05-01

    The time evolution of afterslip on a plate boundary experiencing interplate earthquakes is expected to show logarithmic decay. The global positioning system network in Japan has been monitoring transient deformation since the occurrence of two large interplate earthquakes with moment magnitudes of 6.8 and 6.7 in the Hyuga-nada area, southwest Japan, in 1996. The spatial and temporal evolution of aseismic interplate slip based on crustal deformation data indicates that afterslip followed the two earthquakes and gradually declined to background rates by around 2004 with total moment magnitude of 7.3. However, quasi-periodic slow slip events suddenly began within the afterslip area in 2005 with approximately one year duration and two-year recurrence interval. The moment magnitudes of the three slow slip events since January 2005 range from 6.7 to 6.8. This differs greatly from the expected behavior of logarithmic decay over time. Both velocity-strengthening and velocity-weakening rate-and-state modes have been implicated as the cause of afterslip, whose location is complementary to the main shock area of velocity-weakening, while a slow slip event occurs in the velocity-weakening area with different frictional properties from those of an afterslip area. In light of the seemingly different frictional properties, the coexistence of afterslip and slow slip events in the same area would provide additional information about precisely how the plate interface is behaving. The monitoring of these slow slip events should give the clues to understanding the coexistence of long-term afterslip and slow slip events and the increasing risk of earthquakes in neighboring areas.

  11. FCaZm intelligent recognition system for locating areas prone to strong earthquakes in the Andean and Caucasian mountain belts

    NASA Astrophysics Data System (ADS)

    Gvishiani, A. D.; Dzeboev, B. A.; Agayan, S. M.

    2016-07-01

    The fuzzy clustering and zoning method (FCAZm) of systems analysis is suggested for recognizing the areas of the probable generation of the epicenters of significant, strong, and the strongest earthquakes. FCAZm is a modified version of the previous FCAZ algorithmic system, which is advanced by the creation of the blocks of artificial intelligence that develop the system-forming algorithms. FCAZm has been applied for recognizing areas where the epicenters of the strongest ( M ≥ 73/4) earthquakes within the Andes mountain belt in the South America and significant earthquakes ( M ≥ 5) in the Caucasus can emerge. The reliability of the obtained results was assessed by the seismic-history type control experiments. The recognized highly seismic zones were compared with the ones previously recognized by the EPA method and by the initial version of the FCAZ system. The modified FCAZm system enabled us to pass from simple pattern recognition in the problem of recognizing the locations of the probable emergence of strong earthquakes to systems analysis. In particular, using FCAZm we managed to uniquely recognize a subsystem of highly seismically active zones from the nonempty complement using the exact boundary.

  12. Site responses based on ambient vibrations and earthquake data: a case study from the meizoseismal area of the 2001 Bhuj earthquake

    NASA Astrophysics Data System (ADS)

    Natarajan, Thulasiraman; Rajendran, Kusala

    2016-08-01

    The 2001 Mw 7.6 earthquake sourced in the Kachchh rift of northwest India led to extensive damage in the city of Bhuj, located ~70 km southwest of its epicenter. The building stock of this densely populated city was a mix of modern, single, and multistoried structures as well as traditional and non-engineered abodes, most of which were not designed to withstand severe shaking effects. Although there was extensive liquefaction and ground failure in the meizoseismal area, they were not observed in Bhuj, but the damage was severe here. In this study, we apply horizontal to vertical spectral ratio method to ambient vibrations (HVSR-AV) to obtain fundamental resonance frequency (f0) and H/V peak amplitude (A0) to examine if site response had any significant role in the observed damage. The patterns of H/V curves as well as spatial distributions of f0 (0.6-1.4 Hz) and A0 (1.5-4.4) suggest absence of any strong impedance contrast within the subsurface. Similar results obtained for ambient vibrations and earthquake signals suggest the efficacy of the HVSR-AV method as most useful for regions of low-level seismicity. The weathered sandstone that is generally exposed in the city represents the resonating layer whose thickness is approximately estimated as ~66-155 m, based on 1D assumption. The current set of available data precludes any quantitative modeling, but our preliminary inference is that site effects were not significant during the 2001 earthquake damage observed in Bhuj.

  13. The 2014 M 6.0 South Napa Earthquake in the Context of the Earthquake Cycle in the San Francisco Bay Area

    NASA Astrophysics Data System (ADS)

    Jaume, S. C.

    2014-12-01

    The 2014 M 6.0 South Napa earthquake is the second M ≥ 5.5 earthquake to occur in the San Francisco Bay region since the 1989 M 7.0 Loma Prieta earthquake. This poster will examine how this earthquake fits into the earthquake history of the Bay region, which has shown considerable variation in the rate of moderate (M 5.5-6.5) earthquakes. A number of models have been developed to explain these changes in moderate earthquake rates, including the Accelerating Moment Release model (e.g., Sykes and Jaumé, Nature, 1990; Bufe and Varnes, J. Geophys. Res., 1993) and the Stress Shadow model (e.g., Harris and Simpson, J. Geophys. Res., 1998). In addition, various groups have made projections of future earthquake activity in the San Francisco Bay region, including the Working Group on California Earthquake Probabilities (Field et al., USGS OFR, 2008) and Bebbington et al. (PAGEOPH, 2010), utilizing different physical models for earthquake occurrence. In my poster I will compare and contrast these different views of seismicity in the Bay region and where the 2014 South Napa earthquake fits into them. In particular, I will explore what these different models imply for future moderate earthquake occurrence and hazards thereof.

  14. Workshop on evaluation of earthquake hazards and risk in the Puget Sound and Portland areas

    SciTech Connect

    Hays, W.W.; Kitzmiller, C.

    1988-01-01

    Three tasks were undertaken in the forum provided by the workshop: (1) assessing the present state-of-knowledge of earthquake hazards in Washington and Oregon including scientific, engineering, and hazard-reduction components; (2) determining the need for additional scientific, engineering, and societal response information to implement an effective earthquake-hazard reduction program; and (3) developing a strategy for implementing programs to reduce potential earthquake losses and to foster preparedness and mitigation. Thirty-five papers were given at the workshop and each of these has been abstracted for the U.S. Department of Energy's Energy Data Base (EDB). In addition, the volume includes a glossary of technical terms used in earthquake engineering in Appendix A.

  15. Controls of the Xiannvshan Fault on landslides and Reservoir induced earthquakes located at head area of the Three Gorges Reservoir

    NASA Astrophysics Data System (ADS)

    Shimei, Wang; Yeming, Zhang

    2015-04-01

    Landslides and reservoir induced earthquakes are two main types of geological disasters, which have serious influence on the Three Gorges Project. The Xiannvshan Fault is ten kilometers away from the Three Gorges Dam, and it has important control on landslides and earthquakes located at head area of the Three Gorges Reservoir. Data collected show that: (1) the fault stretch runs in northwest-west orientation with a total length of more than 80 kilometers, it north endpoint extends to the Yangtze River and Jiuwanxi Fault is one of its branches. The Xiannvshan Fault has a high level of activity with the average annual decline of 0.076mm in the west wall and the dextral sliding of 0.116mm. (2) Controls on landslides resulted from the Xiannvshan Fault lie in two aspects. One is a large of landslide accumulation bodies resulted from two collapse events, which are corresponded to the two intense faulting. The other is that the Xintan landslide occurred in 1982, which is resulted from the stress accumulation of the fault. (3) The Xiannvshan Fault is active. Three big earthquakes had been induced by the fault from 1959 to the time of impounding, of which one occurred at its southern endpoint, Panjiawan of Yidu, and was magnitude 5, one occurred at its northern section, Zhou Ping, and was magnitude 3.3, and another occurred at Huilongguan of Zigui with a magnitude 5.1. Earthquakes have been happening more frequently after the impoundment of the Three Gorges Reservoir or on the high water level than before. More than 40 earthquakes with magnitudes bigger than 3.3 were recorded after the impoundment, of which 4 ranged from 4.1 to 5.1 and occurred when the high water level was decreasing. Otherwise, most earthquakes centered on the northern endpoint of the fault, which indicates a characteristics of tectonic reservoir earthquake. This study, for the three gorges reservoir area landslide and seismic reservoir prediction is of great significance.

  16. Detection of Flooded Areas using ALOS/PALSAR Images for the 2008 Iwate-Miyagi Inland Earthquake

    NASA Astrophysics Data System (ADS)

    Kato, Keita; Yamazaki, Fumio

    Synthetic Aperture Radar (SAR) can observe the earth surface in daytime and night-time regardless of weather conditions. Hence it is highly useful to capture damage distributions shortly after natural disasters strike. Detection of flooded areas is carried out using ALOS/PALSAR images acquired before and after the 2008 Iwate-Miyagi Inland earthquake. Because the backscattering echo of SAR shows the condition of the earth surface, the changes of the echo in two images are used to detect the areas covered by water and those dried up after the earthquake. Since many small noises are also extracted from the SAR images, an open-close-scale filter is employed to remove them. The extracted results are compared with the visual detection results from ALOS/AVNIR-2 images and then the accuracy of the proposed method is verified.

  17. Real-time earthquake alert system for the greater San Francisco Bay Area: a prototype design to address operational issues

    SciTech Connect

    Harben, P.E.; Jarpe, S.; Hunter, S.

    1996-12-10

    The purpose of the earthquake alert system (EAS) is to outrun the seismic energy released in a large earthquake using a geographically distributed network of strong motion sensors that telemeter data to a rapid CPU-processing station, which then issues an area-wide warning to a region before strong motion will occur. The warning times involved are short, from 0 to 30 seconds or so; consequently, most responses must be automated. The San Francisco Bay Area is particularly well suited for an EAS because (1) large earthquakes have relatively shallow hypocenters (10- to 20-kilometer depth), giving favorable ray-path geometries for larger warning times than deeper from earthquakes, and (2) the active faults are few in number and well characterized, which means far fewer geographically distributed strong motion sensors are (about 50 in this region). An EAS prototype is being implemented in the San Francisco Bay Area. The system consists of four distinct subsystems: (1) a distributed strong motion seismic network, (2) a central processing station, (3) a warning communications system and (4) user receiver and response systems. We have designed a simple, reliable, and inexpensive strong motion monitoring station that consists of a three-component Analog Devices ADXLO5 accelerometer sensing unit, a vertical component weak motion sensor for system testing, a 16-bit digitizer with multiplexing, and communication output ports for RS232 modem or radio telemetry. The unit is battery-powered and will be sited in fire stations. The prototype central computer analysis system consists of a PC dam-acquisition platform that pipes the incoming strong motion data via Ethernet to Unix-based workstations for dam processing. Simple real-time algorithms, particularly for magnitude estimation, are implemented to give estimates of the time since the earthquake`s onset its hypocenter location, its magnitude, and the reliability of the estimate. These parameters are calculated and transmitted

  18. Earthquake occurrence and effects.

    PubMed

    Adams, R D

    1990-01-01

    Although earthquakes are mainly concentrated in zones close to boundaries of tectonic plates of the Earth's lithosphere, infrequent events away from the main seismic regions can cause major disasters. The major cause of damage and injury following earthquakes is elastic vibration, rather than fault displacement. This vibration at a particular site will depend not only on the size and distance of the earthquake but also on the local soil conditions. Earthquake prediction is not yet generally fruitful in avoiding earthquake disasters, but much useful planning to reduce earthquake effects can be done by studying the general earthquake hazard in an area, and taking some simple precautions. PMID:2347628

  19. Mega-thrust and Intra-slab Earthquakes beneath Tokyo Metropolitan Area around subduction and collision zones in JAPAN

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Kasahara, K.; Hagiwara, H.; Satow, H.; Shimazaki, K.; Koketsu, K.; Wu, F.; Okaya, D.

    2007-12-01

    In central Japan the Philippine Sea plate (PSP) subducts beneath the Tokyo Metropolitan area, the Kanto region, where it causes mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9). The vertical proximity of this down going lithospheric plate is of concern because the greater Tokyo urban region has a population of 42 million and is the center of approximately 40 % of the nation's economic activities. A M7+ earthquake in this region at present has high potential to produce devastating loss of life and property with even greater global economic repercussions.The M7+ earthquake is evaluated to occur with a probability of 70 % in 30 years by the Earthquake Research Committee of Japan.We started the Special Project for Earthquake Disaster Mitigation in Tokyo metropolitan areas, a project to improve information needed for seismic hazards analyses of the largest urban centers. Under the project we will deploy a 400-sation dense seismic array in metropolitan Tokyo and Kanto, referred to as the Metropolitan Seismic Observation network (MeSO-net) in next 4 years. The target area of the present project is unique in tectonic setting because two oceanic plates, Philippine Sea plate (PSP) and Pacific plate (PAC), are subducting beneath the Kanto and also a volcanic arc, Izu-Bonin arc, is colliding with Honshu arc. The situation makes the tectonics complicated: there are both zones of smooth subduction and collision of the oceanic plate with the landward plate, either the Eurasian plate or the North American plate. Furthermore, the PSP encounters the PAC at shallow depth in the eastern Kanto region. The newly developing MeSO-net will contribute to understand the generation mechanism associated with the plate subduction and collision. Assessment in Kanto of the seismic hazard requires identification of all significant faults and possible earthquake scenarios and rupture behavior, regional characterizations of the PSP geometry and

  20. Mega-thrust and Intra-slab Earthquakes beneath Tokyo Metropolitan Area around subduction and collision zones in JAPAN

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Kasahara, K.; Hagiwara, H.; Satow, H.; Shimazaki, K.; Koketsu, K.; Wu, F.; Okaya, D.

    2004-12-01

    In central Japan the Philippine Sea plate (PSP) subducts beneath the Tokyo Metropolitan area, the Kanto region, where it causes mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9). The vertical proximity of this down going lithospheric plate is of concern because the greater Tokyo urban region has a population of 42 million and is the center of approximately 40 % of the nation's economic activities. A M7+ earthquake in this region at present has high potential to produce devastating loss of life and property with even greater global economic repercussions.The M7+ earthquake is evaluated to occur with a probability of 70 % in 30 years by the Earthquake Research Committee of Japan.We started the Special Project for Earthquake Disaster Mitigation in Tokyo metropolitan areas, a project to improve information needed for seismic hazards analyses of the largest urban centers. Under the project we will deploy a 400-sation dense seismic array in metropolitan Tokyo and Kanto, referred to as the Metropolitan Seismic Observation network (MeSO-net) in next 4 years. The target area of the present project is unique in tectonic setting because two oceanic plates, Philippine Sea plate (PSP) and Pacific plate (PAC), are subducting beneath the Kanto and also a volcanic arc, Izu-Bonin arc, is colliding with Honshu arc. The situation makes the tectonics complicated: there are both zones of smooth subduction and collision of the oceanic plate with the landward plate, either the Eurasian plate or the North American plate. Furthermore, the PSP encounters the PAC at shallow depth in the eastern Kanto region. The newly developing MeSO-net will contribute to understand the generation mechanism associated with the plate subduction and collision. Assessment in Kanto of the seismic hazard requires identification of all significant faults and possible earthquake scenarios and rupture behavior, regional characterizations of the PSP geometry and

  1. Environmentally Friendly Solution to Ground Hazards in Design of Bridges in Earthquake Prone Areas Using Timber Piles

    NASA Astrophysics Data System (ADS)

    Sadeghi, H.

    2015-12-01

    Bridges are major elements of infrastructure in all societies. Their safety and continued serviceability guaranties the transportation and emergency access in urban and rural areas. However, these important structures are subject to earthquake induced damages in structure and foundations. The basic approach to the proper support of foundations are a) distribution of imposed loads to foundation in a way they can resist those loads without excessive settlement and failure; b) modification of foundation ground with various available methods; and c) combination of "a" and "b". The engineers has to face the task of designing the foundations meeting all safely and serviceability criteria but sometimes when there are numerous environmental and financial constrains, the use of some traditional methods become inevitable. This paper explains the application of timber piles to improve ground resistance to liquefaction and to secure the abutments of short to medium length bridges in an earthquake/liquefaction prone area in Bohol Island, Philippines. The limitations of using the common ground improvement methods (i.e., injection, dynamic compaction) because of either environmental or financial concerns along with the abundance of timber in the area made the engineers to use a network of timber piles behind the backwalls of the bridge abutments. The suggested timber pile network is simulated by numerical methods and its safety is examined. The results show that the compaction caused by driving of the piles and bearing capacity provided by timbers reduce the settlement and lateral movements due to service and earthquake induced loads.

  2. Bam32: a novel mediator of Erk activation in T cells.

    PubMed

    Sommers, Connie L; Gurson, Jordan M; Surana, Rishi; Barda-Saad, Mira; Lee, Jan; Kishor, Aparna; Li, Wenmei; Gasser, Adam J; Barr, Valarie A; Miyaji, Michihiko; Love, Paul E; Samelson, Lawrence E

    2008-07-01

    Bam32 (B lymphocyte adapter molecule of 32 kDa) is an adapter protein expressed in some hematopoietic cells including B and T lymphocytes. It was previously shown that Bam32-deficient mice have defects in various aspects of B cell activation including B cell receptor (BCR)-induced Erk activation, BCR-induced proliferation and T-independent antibody responses. In this study, we have examined the role of Bam32 in T cell activation using Bam32-deficient mice. By comparing CD4(+) T cells from lymph nodes of wild-type and Bam32-deficient mice, we found that Bam32 was required for optimal TCR-induced Erk activation, cytokine production, proliferation and actin-mediated spreading of CD4(+) T cells. These results indicate a novel pathway to Erk activation in T cells involving the adapter protein Bam32.

  3. Bam32: a novel mediator of Erk activation in T cells

    PubMed Central

    Sommers, Connie L.; Gurson, Jordan M.; Surana, Rishi; Barda-Saad, Mira; Lee, Jan; Kishor, Aparna; Li, WenMei; Gasser, Adam J.; Barr, Valarie A.; Miyaji, Michihiko; Love, Paul E.; Samelson, Lawrence E.

    2009-01-01

    Bam32 (B lymphocyte adapter molecule of 32 kDa) is an adapter protein expressed in some hematopoietic cells including B and T lymphocytes. It was previously shown that Bam32-deficient mice have defects in various aspects of B cell activation including B cell receptor (BCR)-induced Erk activation, BCR-induced proliferation and T-independent antibody responses. In this study, we have examined the role of Bam32 in T cell activation using Bam32-deficient mice. By comparing CD4+ T cells from lymph nodes of wild-type and Bam32-deficient mice, we found that Bam32 was required for optimal TCR-induced Erk activation, cytokine production, proliferation and actin-mediated spreading of CD4+ T cells. These results indicate a novel pathway to Erk activation in T cells involving the adapter protein Bam32. PMID:18448454

  4. Recent Fault Activity in the 1886 Charleston, South Carolina Earthquake Epicentral Area and its Relation to Buried Structures

    NASA Astrophysics Data System (ADS)

    Pratt, T. L.; Shah, A. K.; Horton, J. W., Jr.; Chapman, M. C.; Beale, J.

    2014-12-01

    The 1886 Charleston, SC earthquake (M6.8-7.3) is the largest recorded earthquake to strike the U.S. east of the Appalachian Mountains. It occurred along the U.S. passive margin within an area of extensive Mesozoic rifting and beneath the ~800-m thick, subhorizontal Atlantic Coastal Plain (ACP) strata. The fault(s) that caused the 1886 earthquake remain the subject of debate. We examine reprocessed seismic reflection data in the epicentral area to discern faults cutting the Cretaceous and Cenozoic ACP strata, and relate them to deeper structures revealed by the seismic profiles and filtered aeromagnetic data. Faults are identified on the seismic profiles by sharp vertical displacements of strata, abrupt but small changes in dip, and folding of the ACP strata. Some of these faults dip steeply and locally displace deeper reflectors within the underlying South Georgia rift basin with minor displacement; in places they bound uplifted blocks of ACP strata. These observations and the lack of surface scarps during the 1886 earthquake suggest a component of strike-slip for the Cretaceous and Cenozoic displacements, whereas some modern focal mechanisms show thrust motion. A prominent magnetic anomaly high shows a NE-trending west edge in the epicentral area, and short-wavelength magnetic anomalies show disruptions aligned along NE trends. These latter disruptions appear to be related to the seismically imaged faults that offset ACP strata. One of the faults, previously interpreted by Chapman and Beale (2010), shows folding and perhaps faulting of ACP strata with ~50 m vertical displacement and is aligned along the NW edge of the magnetic high. The vertical uplift is nearly equal through the ACP section with little or no upward decrease across the fault, indicating the motion is primarily Cenozoic. The fault lies near Summerville about 35 km NW of Charleston, where 1886 ground deformation was focused. Another NE-trending fault, crossing beneath the Ashley River ~15 km NW of

  5. The psychological impact of the Bay Area earthquake on health professionals.

    PubMed

    Kaltreider, N; Gracie, C; LeBreck, D

    1992-01-01

    An earthquake exemplifies a natural disaster in which the potential caregivers are experiencing their own emotional response to the event. A survey of 222 health care workers in San Francisco and Marin County in the first two weeks after the Loma Prieta earthquake found them to have a moderate level of psychological symptoms as measured by the Impact of Event Scale and to frequently endorse several earthquake specific stress items. Highly reliable gender differences existed on all of the dependent variables, with women reporting more symptoms. Variation in cognitive style and the personal salience of the event are possible explanations for this difference. Disaster planning should include education about the normal range of response and support groups for symptomatic caregivers as well as victims.

  6. Effect of the Loma Prieta Earthquake on surface slip along the Calaveras Fault in the Hollister area

    NASA Astrophysics Data System (ADS)

    Galehouse, Jon S.

    Over the past ten years we have made over 800 measurements of slip rates at 20 sites on various faults in the San Francisco Bay region. This data set enables us to compare rates and amounts of slip on these various faults before and after the Loma Prieta earthquake (LPEQ) on the San Andreas fault. No surface slip rate changes associated with the earthquake occurred at any of our sites on the San Andreas, Hayward, northern Calaveras, Concord-Green Valley, Seal Cove-San Gregorio, Antioch, Rodgers Creek, or West Napa faults. The LPEQ apparently triggered up to 12-14 mm of right slip on the southern Calaveras fault at our two sites in the Hollister area less than 50 km from the epicenter. Most of this slip was probably coseismic or nearly so. About the same amount of slip was triggered at these sites in 1984 by the Morgan Hill earthquake. This slip, in contrast, occurred as afterslip within about a 2.5-month interval. The Calaveras fault in the Hollister area moves episodically, with shorter times of more rapid slip alternating with longer times of slower slip. The alternation occurs whether or not the times of faster slip are triggered by any nearby seismic event(s).

  7. Sediment source areas of earthquake-triggered megaturbidites in marine or lacustrine confined basins: implications for regional paleoseismicity

    NASA Astrophysics Data System (ADS)

    emmanuel, Chapron; Hervé, Guyard; Flavio, Anselmetti; Giuseppe, Siani

    2016-04-01

    Earthquake triggered megaturbidites documented in different confined Mediterranean confined basins are bearing several similarities with so-called seiche deposits induced by earthquakes in several large and deep Alpine lakes. Both of these mega beds are resulting from coeval subaquatic slope failures and the propagation of violent waves developing erosive currents along shore lines and shallow water depths but also locally within deep waters. They have a similar acoustic signature (i.e. a decimetric to plurimetric transparent acoustic facies ponded in the deepest part of confined basins with a high-amplitude basal reflection) and are characterized by maximal thicknesses ranging between 0.2 and 1.6 % of the basin's water depth. While lacustrine megaturbidites are essentially resulting from the remobilization of fine-grained clastic sediments (either deltaic depot-centers or slopes loaded by sediment plumes during deglaciation) and shallow water coarser particles by waves and bottom currents; little is known about the soft-sediment source areas of megaturbidites in the Mediterranean. Based on our understanding of sedimentary process associated with seiche deposits in lakes and taking into consideration the oceanographic characteristics of the Mediterranean Sea, multiples soft-sediment source areas can be identified and a new conceptual depositional model can be proposed for the development of tsunamigenic earthquake-triggered megaturbidites.

  8. Effect of the Loma Prieta earthquake on surface slip along the Calaveras fault in the Hollister area

    SciTech Connect

    Galehouse, J.S. )

    1990-07-01

    Over the past ten years the author has made over 800 measurements of slip rates at 20 sites on various faults in the San Francisco Bay region. This data set enables them to compare rates and amounts of slip on these various faults before and after the Loma Prieta earthquake (LPEQ) on the San Andreas fault. No surface slip rate changes associated with the earthquake occurred at any of the sites on the San Andreas, Hayward, northern Calaveras, Concord-Green Valley, Seal Cove-San Gregorio, Antioch, Rodgers Creek, or West Napa faults. The LPEQ apparently triggered up to 12-14 mm of right slip on the southern Calaveras fault at two sites in the Hollister area less than 50 km from the epicenter. Most of this slip was probably coseismic or nearly so. About the same amount of slip was triggered at these sites in 1984 by the Morgan Hill earthquake. This slip, in contrast, occurred as afterslip within about a 2.5-month interval. The Calaveras fault in the Hollister area moves episodically, with shorter times of more rapid slip alternating with longer times of slower slip. The alternation occurs whether or not the times of faster slip are triggered by any nearby seismic event(s).

  9. Earthquake Risk Management of Underground Lifelines in the Urban Area of Catania

    SciTech Connect

    Grasso, S.; Maugeri, M.

    2008-07-08

    Lifelines typically include the following five utility networks: potable water, sewage natural gas, electric power, telecommunication and transportation system. The response of lifeline systems, like gas and water networks, during a strong earthquake, can be conveniently evaluated with the estimated average number of ruptures per km of pipe. These ruptures may be caused either by fault ruptures crossing, or by permanent deformations of the soil mass (landslides, liquefaction), or by transient soil deformations caused by seismic wave propagation. The possible consequences of damaging earthquakes on transportation systems may be the reduction or the interruption of traffic flow, as well as the impact on the emergency response and on the recovery assistance. A critical element in the emergency management is the closure of roads due to fallen obstacles and debris of collapsed buildings.The earthquake-induced damage to buried pipes is expressed in terms of repair rate (RR), defined as the number of repairs divided by the pipe length (km) exposed to a particular level of seismic demand; this number is a function of the pipe material (and joint type), of the pipe diameter and of the ground shaking level, measured in terms of peak horizontal ground velocity (PGV) or permanent ground displacement (PGD). The development of damage algorithms for buried pipelines is primarily based on empirical evidence, tempered with engineering judgment and sometimes by analytical formulations.For the city of Catania, in the present work use has been made of the correlation between RR and peak horizontal ground velocity by American Lifelines Alliance (ALA, 2001), for the verifications of main buried pipelines. The performance of the main buried distribution networks has been evaluated for the Level I earthquake scenario (January 11, 1693 event I = XI, M 7.3) and for the Level II earthquake scenario (February 20, 1818 event I = IX, M 6.2).Seismic damage scenario of main gas pipelines and

  10. Earthquake Risk Management of Underground Lifelines in the Urban Area of Catania

    NASA Astrophysics Data System (ADS)

    Grasso, S.; Maugeri, M.

    2008-07-01

    Lifelines typically include the following five utility networks: potable water, sewage natural gas, electric power, telecommunication and transportation system. The response of lifeline systems, like gas and water networks, during a strong earthquake, can be conveniently evaluated with the estimated average number of ruptures per km of pipe. These ruptures may be caused either by fault ruptures crossing, or by permanent deformations of the soil mass (landslides, liquefaction), or by transient soil deformations caused by seismic wave propagation. The possible consequences of damaging earthquakes on transportation systems may be the reduction or the interruption of traffic flow, as well as the impact on the emergency response and on the recovery assistance. A critical element in the emergency management is the closure of roads due to fallen obstacles and debris of collapsed buildings. The earthquake-induced damage to buried pipes is expressed in terms of repair rate (RR), defined as the number of repairs divided by the pipe length (km) exposed to a particular level of seismic demand; this number is a function of the pipe material (and joint type), of the pipe diameter and of the ground shaking level, measured in terms of peak horizontal ground velocity (PGV) or permanent ground displacement (PGD). The development of damage algorithms for buried pipelines is primarily based on empirical evidence, tempered with engineering judgment and sometimes by analytical formulations. For the city of Catania, in the present work use has been made of the correlation between RR and peak horizontal ground velocity by American Lifelines Alliance (ALA, 2001), for the verifications of main buried pipelines. The performance of the main buried distribution networks has been evaluated for the Level I earthquake scenario (January 11, 1693 event I = XI, M 7.3) and for the Level II earthquake scenario (February 20, 1818 event I = IX, M 6.2). Seismic damage scenario of main gas pipelines and

  11. Large-scale mapping of landslides in the epicentral area Loma Prieta earthquake of October 17, 1989, Santa Cruz County

    SciTech Connect

    Spittler, T.E.; Sydnor, R.H.; Manson, M.W.; Levine, P.; McKittrick, M.M.

    1990-01-01

    The Loma Prieta earthquake of October 17, 1989 triggered landslides throughout the Santa Cruz Mountains in central California. The California Department of Conservation, Division of Mines and Geology (DMG) responded to a request for assistance from the County of Santa Cruz, Office of Emergency Services to evaluate the geologic hazard from major reactivated large landslides. DMG prepared a set of geologic maps showing the landslide features that resulted from the October 17 earthquake. The principal purpose of large-scale mapping of these landslides is: (1) to provide county officials with regional landslide information that can be used for timely recovery of damaged areas; (2) to identify disturbed ground which is potentially vulnerable to landslide movement during winter rains; (3) to provide county planning officials with timely geologic information that will be used for effective land-use decisions; (4) to document regional landslide features that may not otherwise be available for individual site reconstruction permits and for future development.

  12. Geomorphic changes induced by the April-May 2015 earthquake sequence in the Pharak-Khumbu area (Nepal): preliminary assessments.

    NASA Astrophysics Data System (ADS)

    Fort, Monique

    2016-04-01

    Landsliding is a common process shaping mountain slopes. There are various potential landslide triggers (rainfall, bank erosion, earthquakes) and their effectiveness depends on their distribution, frequency and magnitude. In a Himalayan context, the effects of monsoon rainfall can be assessed every year whereas the unpredictability and low frequency of large earthquakes make their role in triggering slope instability more obscure. A 7.8 magnitude earthquake struck central Nepal (Gorkha District) on 25 April 2015 and was followed by many aftershocks exceeding magnitude 5, including another strong 7.3 magnitude earthquake on May 12, 2015 (Dolakha District). This seismic crisis provides an exceptional opportunity to assess the disruptions that earthquakes may cause in "regular" geomorphic systems controlled by rainfall. Here we present field observations carried out in the Pharak-Khumbu area (East Nepal, Dudh Kosi catchment) before and after the April-May 2015 earthquakes. The Pharak, a "middle mountains" (2000-4500 m) area, is affected by monsoon rains (3000 m/yr at 2500 m) and characterised by steep hillslopes, shaped by different geomorphic processes according to slope height and aspect, rock type and strength, inherited landforms, stream connectivity and current land use changes. This study focuses on the south of Lukla (Phakding District), and more specifically on the Khari Khola catchment and its surroundings. The area lies at the transition between the Higher Himalayan crystallines and the Lesser Himalayan meta-sediments. On the basis of our diachronic observations (March and November 2015), we surveyed and mapped new earthquake-induced slope instabilities such as rock falls, rockslides, landslides and debris flows and a combination of several of them. Interviews with local people also helped to assess the exact timing of some events. While the first M 7.8 earthquake produced significant impacts in the northern Khumbu area, the M 7.3 aftershock seems to have

  13. Examining and Comparing Earthquake Readiness in East San Francisco Bay Area Communities (Invited)

    NASA Astrophysics Data System (ADS)

    Ramirez, N.; Bul, V.; Chavez, A.; Chin, W.; Cuff, K. E.; Girton, C.; Haynes, D.; Kelly, G.; Leon, G.; Ramirez, J.; Ramirez, R.; Rodriquez, F.; Ruiz, D.; Torres, J.

    2009-12-01

    Based on past experiences, the potential for casualties and mass destruction that can result from a high magnitude earthquake are well known. Nevertheless, given the East San Francisco Bay Area’s proximity to the Hayward and San Andreas faults, learning about earthquakes and disaster preparedness is of particular importance. While basic educational programs and materials are available both through emergency relief agencies and schools, little research has been done on their effectiveness. Because of the wide socioeconomic spread between communities in the East Bay, we decided to investigate understandings of issues related to disaster and earthquake preparedness among local populations based upon average household income. To accomplish this, we created a survey that was later uploaded to and implemented using Palm Treo Smart Phones. Survey locations were selected in such a way that they reflected the understandings of residents in a diverse set of socio-economic settings. Thus, these locations included a grocery store and nearby plaza in the Fruitvale district of Oakland, CA (zip=94601; median household income= 33,152), as well as the nearby town of Alameda, CA (zip=94502, median household income= 87,855). Preliminary results suggest that in terms of the objective questions on the survey, people from Alameda who participated in our study performed significantly better (difference in percentage correct greater than 10%) than the people from Fruitvale on two of the advanced earthquake knowledge questions. Interestingly enough, people in Fruitvale significantly outperformed people in Alameda on two of the basic earthquake knowledge questions. The final important finding was that while houses in Alameda tended to be newer and more often retrofitted than houses in Fruitvale, the people of the latter location tended to have a higher percentage of respondents claim confidence in the ability of their house to withstand a major earthquake. Based on preliminary results we

  14. Special Issue "Impact of Natural Hazards on Urban Areas and Infrastructure" in the Bulletin of Earthquake Engineering

    NASA Astrophysics Data System (ADS)

    Bostenaru Dan, M.

    2009-04-01

    This special issue includes selected papers on the topic of earthquake impact from the sessions held in 2004 in Nice, France and in 2005 in Vienna, Austria at the first and respectivelly the second European Geosciences Union General Assembly. Since its start in 1999, in the Hague, Netherlands, the hazard of earthquakes has been the most popular of the session. The respective calls in 2004 was for: Nature's forces including earthquakes, floods, landslides, high winds and volcanic eruptions can inflict losses to urban settlements and man-made structures such as infrastructure. In Europe, recent years have seen such significant losses from earthquakes in south and south-eastern Europe, floods in central Europe, and wind storms in western Europe. Meanwhile, significant progress has been made in understanding disasters. Several scientific fields contribute to a holistic approach in the evaluation of capacities, vulnerabilities and hazards, the main factors on mitigating urban disasters due to natural hazards. An important part of the session is devoted to assessment of earthquake shaking and loss scenarios, including both physical damage and human causalities. Early warning and rapid damage evaluation are of utmost importance for addressing the safety of many essential facilities, for emergency management of events and for disaster response. In case of earthquake occurrence strong motion networks, data processing and interpretation lead to preliminary estimation (scenarios) of geographical distribution of damages. Factual information on inflicted damage, like those obtained from shaking maps or aerial imagery permit a confrontation with simulation maps of damage in order to define a more accurate picture of the overall losses. Most recent developments towards quantitative and qualitative simulation of natural hazard impacts on urban areas, which provide decision-making support for urban disaster management, and success stories of and lessons learned from disaster

  15. Creating a Global Building Inventory for Earthquake Loss Assessment and Risk Management

    USGS Publications Warehouse

    Jaiswal, Kishor; Wald, David J.

    2008-01-01

    Earthquakes have claimed approximately 8 million lives over the last 2,000 years (Dunbar, Lockridge and others, 1992) and fatality rates are likely to continue to rise with increased population and urbanizations of global settlements especially in developing countries. More than 75% of earthquake-related human casualties are caused by the collapse of buildings or structures (Coburn and Spence, 2002). It is disheartening to note that large fractions of the world's population still reside in informal, poorly-constructed & non-engineered dwellings which have high susceptibility to collapse during earthquakes. Moreover, with increasing urbanization half of world's population now lives in urban areas (United Nations, 2001), and half of these urban centers are located in earthquake-prone regions (Bilham, 2004). The poor performance of most building stocks during earthquakes remains a primary societal concern. However, despite this dark history and bleaker future trends, there are no comprehensive global building inventories of sufficient quality and coverage to adequately address and characterize future earthquake losses. Such an inventory is vital both for earthquake loss mitigation and for earthquake disaster response purposes. While the latter purpose is the motivation of this work, we hope that the global building inventory database described herein will find widespread use for other mitigation efforts as well. For a real-time earthquake impact alert system, such as U.S. Geological Survey's (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER), (Wald, Earle and others, 2006), we seek to rapidly evaluate potential casualties associated with earthquake ground shaking for any region of the world. The casualty estimation is based primarily on (1) rapid estimation of the ground shaking hazard, (2) aggregating the population exposure within different building types, and (3) estimating the casualties from the collapse of vulnerable buildings. Thus, the

  16. Degradation of the herbicide dichlobenil and its metabolite BAM in soils and subsurface sediments.

    PubMed

    Clausen, Liselotte; Arildskov, Niels P; Larsen, Flemming; Aamand, Jens; Albrechtsen, Hans-Jørgen

    2007-01-30

    The worldwide used herbicide dichlobenil (2,6-dichlorobenzonitrile) has resulted in widespread presence of its metabolite 2,6-dichlorobenzamide (BAM) in surface water and groundwater. To evaluate the potential for natural attenuation of this BAM pollution in groundwater, we studied the degradation of BAM and dichlobenil in 16 samples of clayey till, unconsolidated sand and limestone, including sediments from both oxidized and reduced conditions. The degradation of dichlobenil occurred primarily in the upper few meters below surface, although dichlobenil was strongly sorbed to these sediments. However, the degradation of dichlobenil to BAM could not be correlated to either sorption, water chemistry, composition of soils or sediments. Degradation of dichlobenil to BAM was limited (<2% degraded) in the deeper unsaturated zones, and no degradation was observed in aquifer sediments. This illustrates, that dichlobenil transported to aquifers does not contribute to the BAM-contamination in aquifers. A small, but significant degradation of BAM was observed in the upper part of the unsaturated zones in sandy sediments, but no degradation was observed in the clayey till sediment or in the deeper unsaturated zones. The insignificant degradation of BAM in aquifer systems shows that BAM pollution detected in aquifers will appear for a long time; and consequently the potential for natural attenuation of BAM in aquifer systems is limited.

  17. Estimation of Damaged Areas due to the 2010 Chile Earthquake and Tsunami Using SAR Imagery of Alos/palsar

    NASA Astrophysics Data System (ADS)

    Made, Pertiwi Jaya Ni; Miura, Fusanori; Besse Rimba, A.

    2016-06-01

    A large-scale earthquake and tsunami affect thousands of people and cause serious damages worldwide every year. Quick observation of the disaster damage is extremely important for planning effective rescue operations. In the past, acquiring damage information was limited to only field surveys or using aerial photographs. In the last decade, space-borne images were used in many disaster researches, such as tsunami damage detection. In this study, SAR data of ALOS/PALSAR satellite images were used to estimate tsunami damage in the form of inundation areas in Talcahuano, the area near the epicentre of the 2010 Chile earthquake. The image processing consisted of three stages, i.e. pre-processing, analysis processing, and post-processing. It was conducted using multi-temporal images before and after the disaster. In the analysis processing, inundation areas were extracted through the masking processing. It consisted of water masking using a high-resolution optical image of ALOS/AVNIR-2 and elevation masking which built upon the inundation height using DEM image of ASTER-GDEM. The area result was 8.77 Km2. It showed a good result and corresponded to the inundation map of Talcahuano. Future study in another area is needed in order to strengthen the estimation processing method.

  18. Large and great earthquakes in the Shillong plateau-Assam valley area of Northeast India Region: Pop-up and transverse tectonics

    NASA Astrophysics Data System (ADS)

    Kayal, J. R.; Arefiev, S. S.; Baruah, Saurabh; Hazarika, D.; Gogoi, N.; Gautam, J. L.; Baruah, Santanu; Dorbath, C.; Tatevossian, R.

    2012-04-01

    The tectonic model of the Shillong plateau and Assam valley in the northeast India region, the source area for the 1897 great earthquake (Ms ~ 8.7) and for the four (1869, 1923, 1930 and 1943) large earthquakes (M. ≥ 7.0), is examined using the high precision data of a 20-station broadband seismic network. About 300 selected earthquakes M ≥ 3.0 recorded during 2001-2009 are analysed to study the seismicity and fault plane solutions. The dominating thrust/reverse faulting earthquakes in the western plateau may be explained by the proposed pop-up tectonics between two active boundary faults, the Oldham-Brahmaputra fault to the north and the Dapsi-Dauki thrust to the south, though the northern boundary fault is debated. The more intense normal and strike-slip faulting earthquakes in the eastern plateau (Mikir massif) and in the Assam valley, on the other hand, are well explained by transverse tectonics at the long and deep rooted Kopili fault that cuts across the Himalaya and caused the 2009 Bhutan earthquake (Mw 6.3). It is conjectured that the complex tectonics of the Shillong plateau and transverse tectonics at the Kopili fault make the region vulnerable for impending large earthquake(s).

  19. Seismic tomography of the area of the 2010 Beni-Ilmane earthquake sequence, north-central Algeria.

    PubMed

    Abacha, Issam; Koulakov, Ivan; Semmane, Fethi; Yelles-Chaouche, Abd Karim

    2014-01-01

    The region of Beni-Ilmane (District of M'sila, north-central Algeria) was the site of an earthquake sequence that started on 14 May 2010. This sequence, which lasted several months, was triggered by conjugate E-W reverse and N-S dextral faulting. To image the crustal structure of these active faults, we used a set of 1406 well located aftershocks events and applied the local tomography software (LOTOS) algorithm, which includes absolute source location, optimization of the initial 1D velocity model, and iterative tomographic inversion for 3D seismic P- and S-wave velocities (and the Vp/Vs ratio), and source parameters. The patterns of P-wave low-velocity anomalies correspond to the alignments of faults determined from geological evidence, and the P-wave high-velocity anomalies may represent rigid blocks of the upper crust that are not deformed by regional stresses. The S-wave low-velocity anomalies coincide with the aftershock area, where relatively high values of Vp/Vs ratio (1.78) are observed compared with values in the surrounding areas (1.62-1.66). These high values may indicate high fluid contents in the aftershock area. These fluids could have been released from deeper levels by fault movements during earthquakes and migrated rapidly upwards. This hypothesis is supported by vertical sections across the study area show that the major Vp/Vs anomalies are located above the seismicity clusters.

  20. Hadoop-BAM: directly manipulating next generation sequencing data in the cloud.

    PubMed

    Niemenmaa, Matti; Kallio, Aleksi; Schumacher, André; Klemelä, Petri; Korpelainen, Eija; Heljanko, Keijo

    2012-03-15

    Hadoop-BAM is a novel library for the scalable manipulation of aligned next-generation sequencing data in the Hadoop distributed computing framework. It acts as an integration layer between analysis applications and BAM files that are processed using Hadoop. Hadoop-BAM solves the issues related to BAM data access by presenting a convenient API for implementing map and reduce functions that can directly operate on BAM records. It builds on top of the Picard SAM JDK, so tools that rely on the Picard API are expected to be easily convertible to support large-scale distributed processing. In this article we demonstrate the use of Hadoop-BAM by building a coverage summarizing tool for the Chipster genome browser. Our results show that Hadoop offers good scalability, and one should avoid moving data in and out of Hadoop between analysis steps. PMID:22302568

  1. BAM learning of nonlinearly separable tasks by using an asymmetrical output function and reinforcement learning.

    PubMed

    Chartier, Sylvain; Boukadoum, Mounir; Amiri, Mahmood

    2009-08-01

    Most bidirectional associative memory (BAM) networks use a symmetrical output function for dual fixed-point behavior. In this paper, we show that by introducing an asymmetry parameter into a recently introduced chaotic BAM output function, prior knowledge can be used to momentarily disable desired attractors from memory, hence biasing the search space to improve recall performance. This property allows control of chaotic wandering, favoring given subspaces over others. In addition, reinforcement learning can then enable a dual BAM architecture to store and recall nonlinearly separable patterns. Our results allow the same BAM framework to model three different types of learning: supervised, reinforcement, and unsupervised. This ability is very promising from the cognitive modeling viewpoint. The new BAM model is also useful from an engineering perspective; our simulations results reveal a notable overall increase in BAM learning and recall performances when using a hybrid model with the general regression neural network (GRNN). PMID:19596635

  2. Neotectonics of the Dinarides-Pannonian Basin transition and possible earthquake sources in the Banja Luka epicentral area

    NASA Astrophysics Data System (ADS)

    Ustaszewski, Kamil; Herak, Marijan; Tomljenović, Bruno; Herak, Davorka; Matej, Srebrenka

    2014-12-01

    This study provides evidence for post-5 Ma shortening in the transition area between the Dinarides fold-and-thrust belt and the Pannonian Basin and reviews possible earthquake sources for the Banja Luka epicentral area (northern Bosnia and Herzegovina) where the strongest instrumentally recorded earthquake (ML 6.4) occurred on 27 October 1969. Geological, geomorphological and reflection seismic data provide evidence for a contractional reactivation of Late Palaeogene to Middle Miocene normal faults at slip rates below 0.1 mm/a. This reactivation postdates deposition of the youngest sediments in the Pannonian Basin of Pontian age (c. 5 Ma). Fault plane solutions for the main 1969 Banja Luka earthquake (ML 6.4) and its largest foreshock (ML 6.0) indicate reverse faulting along ESE-WNW-striking nodal planes and generally N-S trending pressure axes. The spatial distribution of epicentres and focal depths, analyses of the macroseismic field and fault-plane solutions for several smaller events suggest on-going shortening in the internal Dinarides. Seismic deformation of the upper crust is also associated with strike-slip faults, likely related to the NE-SW trending, sinistral Banja Luka fault. Possibly, this fault transfers contraction between adjacent segments of the Dinarides thrust system. The study area represents the seismically most active region of the Dinarides apart from the Adriatic Sea coast and the bend zone around Zagreb. We propose that on-going thrusting in the internal Dinarides thrust system takes up a portion of the current Adria-Europe convergence.

  3. Liquefaction-fluidization induced land subsidence: impact of the 2011 Tohoku earthquake on reclaimed land around Tokyo bay area, Japan

    NASA Astrophysics Data System (ADS)

    Kagawa, A.; Furuno, K.; Kusuda, T.; Sakai, Y.; Yoshida, T.; Kazaoka, O.

    2015-11-01

    The 2011 Tohoku earthquake caused major liquefaction-induced, ground deformation of the reclaimed land surrounding Tokyo Bay. In this area, liquefaction was visibly manifest by sand boils, ejection of sandy water, land subsidence and floating underground tanks. The level measurements show a correspondence between the degree of liquefaction-fluidization and the amount of subsidence. The strata most susceptible to liquefaction are hydraulically emplaced dredged fill and artificial strata on thick uncompacted Holocene deposits. On the other hand, the phenomena of seismic isolation coursed by liquefaction had saved the single-family houses from collapse.

  4. Wave equation-based reflection tomography of the 1992 Landers earthquake area

    NASA Astrophysics Data System (ADS)

    Huang, Xueyuan; Yang, Dinghui; Tong, Ping; Badal, José; Liu, Qinya

    2016-03-01

    In the framework of a recent wave equation-based traveltime seismic tomography, we show that incorporating Moho-reflected phases (PmP and SmS) in addition to the direct P and S phases can significantly increase tomography resolution in the lower crust and this may provide additional evidence to resolve important tectonic issues. To highlight the resolving power of the new strategy, we apply it in the region around the 1992 Landers earthquake (Mw = 7.3) in Southern California using seismic arrivals from local earthquakes, obtaining 3-D high-resolution P and S wave crustal velocity models and Poisson's ratio structures. In the upper crust, our method confirmed features that had been previously found. However, in the middle-to-lower crust, we found low-velocity anomalies on the southeastern section of the San Jacinto Fault and high Vp and low Vs structures to the west of the Big Bear earthquake, which may be related to upwelling of partial melt from the mantle.

  5. Environmental risk evaluation to minimize impacts within the area affected by the Wenchuan earthquake.

    PubMed

    Du, Pengfei; Chen, Jining; Chen, Chao; Liu, Yi; Liu, Jianguo; Wang, Hongtao; Zhang, Xiaojian

    2012-03-01

    Earthquakes can be devastating to built infrastructure and the natural environment, as evidenced by the March 2011, M=9.0 earthquake, and subsequent tsunami, in Japan. As seen in the Japanese event, environmental damage caused by secondary disasters (tsunami, leakage from a nuclear reactor) can equal or exceed the impacts of the primary event. In order to develop an environmental assessment system to examine secondary disasters, a comprehensive environmental impact evaluation was conducted after the Wenchuan earthquake that occurred on 12 May 2008 in the Sichuan Province, China. This evaluation focused on several key environmental elements such as wastewater, drinking water, soil, solid waste, radiation, and ecosystem-level effects. As part of this assessment, an analysis of root causes and potential solutions was conducted for key issues such as population relocation and resettlement in temporary dwellings, recovery of environmental protection functions, industrial development strategies and production recovery. Methods for post-quake environmental assessment were developed, utilizing GIS-based techniques for spatial evaluation of primary and secondary disaster patterns. The goal of this exercise was the development of effective assessment methods that can be rapidly applied in a post-disaster situation to reduce and mitigate damage caused by secondary disasters, and facilitate the recovery of impaired environmental management structure and function. PMID:22285064

  6. Environmental risk evaluation to minimize impacts within the area affected by the Wenchuan earthquake.

    PubMed

    Du, Pengfei; Chen, Jining; Chen, Chao; Liu, Yi; Liu, Jianguo; Wang, Hongtao; Zhang, Xiaojian

    2012-03-01

    Earthquakes can be devastating to built infrastructure and the natural environment, as evidenced by the March 2011, M=9.0 earthquake, and subsequent tsunami, in Japan. As seen in the Japanese event, environmental damage caused by secondary disasters (tsunami, leakage from a nuclear reactor) can equal or exceed the impacts of the primary event. In order to develop an environmental assessment system to examine secondary disasters, a comprehensive environmental impact evaluation was conducted after the Wenchuan earthquake that occurred on 12 May 2008 in the Sichuan Province, China. This evaluation focused on several key environmental elements such as wastewater, drinking water, soil, solid waste, radiation, and ecosystem-level effects. As part of this assessment, an analysis of root causes and potential solutions was conducted for key issues such as population relocation and resettlement in temporary dwellings, recovery of environmental protection functions, industrial development strategies and production recovery. Methods for post-quake environmental assessment were developed, utilizing GIS-based techniques for spatial evaluation of primary and secondary disaster patterns. The goal of this exercise was the development of effective assessment methods that can be rapidly applied in a post-disaster situation to reduce and mitigate damage caused by secondary disasters, and facilitate the recovery of impaired environmental management structure and function.

  7. Spatio-temporal distribution of seismic moment release near the source area of the 2011 Tohoku-Oki earthquake

    NASA Astrophysics Data System (ADS)

    Lin, Jing-Yi; Wu, Wen-Nan

    2012-12-01

    To understand the generation mechanism of the 2011 Tohoku-Oki earthquake, we analyzed the spatial and temporal distribution of the cumulative seismic moment (Σ M 0) for all earthquakes along the Japan Trench listed in the global centroid moment tensor catalog between January 1976 and November 2011. Three areas with distinct characteristics of Σ M 0 are identified: (1) in the 2011 Tohoku-Oki source area, the Σ M 0 released in the down-dip portion (≥30 km) was greater than that in the up-dip portion (<30 km) before the mainshock; (2) the Σ M 0 of the up-dip portion in the region where slow slip activity prevails is greater than that of the down-dip portion throughout the study period; (3) in the surroundings of the source area, where interplate coupling is relatively low and the largest foreshock occurred, values of Σ M 0 for the down-dip and up-dip portions are both intermediate. Our results show that a megathrust rupture could be generated by large accumulations of strain energy at the subduction interface, resulting from the differential strain energy released in the down-dip and up-dip portions during the interseismic interval. We propose that the variation pattern of Σ M 0 may offer spatial constraints for seismic hazard assessment in the future.

  8. Asymmetric DNA recognition by the OkrAI endonuclease, an isoschizomer of BamHI

    SciTech Connect

    Vanamee, Éva Scheuring; Viadiu, Hector; Chan, Siu-Hong; Ummat, Ajay; Hartline, Adrian M.; Xu, Shuang-yong; Aggarwal, Aneel K.

    2011-11-18

    Restriction enzymes share little or no sequence homology with the exception of isoschizomers, or enzymes that recognize and cleave the same DNA sequence. We present here the structure of a BamHI isoschizomer, OkrAI, bound to the same DNA sequence (TATGGATCCATA) as that cocrystallized with BamHI. We show that OkrAI is a more minimal version of BamHI, lacking not only the N- and C-terminal helices but also an internal 310 helix and containing {beta}-strands that are shorter than those in BamHI. Despite these structural differences, OkrAI recognizes the DNA in a remarkably similar manner to BamHI, including asymmetric contacts via C-terminal 'arms' that appear to 'compete' for the minor groove. However, the arms are shorter than in BamHI. We observe similar DNA-binding affinities between OkrAI and BamHI but OkrAI has higher star activity (at 37 C) compared to BamHI. Together, the OkrAI and BamHI structures offer a rare opportunity to compare two restriction enzymes that work on exactly the same DNA substrate.

  9. "Routine" versus earthquake-related behavior in Na-K-Mg geothermometry records of Vrancea area (Romania)

    NASA Astrophysics Data System (ADS)

    Mitrofan, H.; Chitea, F.; Marin, C.; Zugravescu, D.; Besutiu, L.; Tudorache, A.

    2009-04-01

    A several-years long geochemical monitoring operation has been initiated in April 2003, addressing a deep-origin groundwater discharge at Slanic Moldova, close to Vrancea seismic area. In order to interpret the evolution of the major cations concentrations, the Na-K-Mg geothermometer diagnosis method has been used. Similarly to results previously obtained worldwide (California; southwest Egypt), an anomalous fluctuation of the so-called "Na-K temperature" (a parameter which is assumed to approximate temperatures existing in a deep origin groundwater reservoir) has been detected on occurrence of a major earthquake (27 October 2004, Mw=5.8-6.0). The earthquake epicenter was positioned at 50 km away from the geochemical sampling site, the focal depth being approximately 95 km. Generally, Na-K temperature fluctuations may also occur "routinely", as a result of the admixture of various amounts of shallow, meteorically-derived waters, or due to variable degrees of chemical re-equilibration at shallower depths / lower temperatures. It was therefore important to investigate if the variations observed in the data values could be plausibly related to a seismogeneis process. In this respect, an appropriate diagnosis should be provided by a so-called "maturity index": that parameter estimates - by additionally considering the fast-readjusting K/Mg solute ratio - the hydrothermal solution departure from the chemical equilibrium state mirrored by the "Na-K temperature". By plotting the maturity index versus the Na-K temperature values for the Slanic Moldova spring, two distinct regimes became noticeable: one consisting of highly correlated data-points, occurring as a dense "cluster", and the other one including a series of more poorly correlated data-points, which appeared to "drift away" from the main "cluster". The "cluster" regime persisted during the entire period (in excess of 3 years) that followed the strongest Vrancea earthquake (27 October 2004, Mw=5.8-6.0) recorded

  10. Seismically active area monitoring by robust TIR satellite techniques: a sensitivity analysis on low magnitude earthquakes in Greece and Turkey

    NASA Astrophysics Data System (ADS)

    Corrado, R.; Caputo, R.; Filizzola, C.; Pergola, N.; Pietrapertosa, C.; Tramutoli, V.

    2005-01-01

    Space-time TIR anomalies, observed from months to weeks before earthquake occurrence, have been suggested by several authors as pre-seismic signals. Up to now, such a claimed connection of TIR emission with seismic activity has been considered with some caution by scientific community mainly for the insufficiency of the validation data-sets and the scarce importance attached by those authors to other causes (e.g. meteorological) that, rather than seismic activity, could be responsible for the observed TIR signal fluctuations. A robust satellite data analysis technique (RAT) has been recently proposed which, thanks to a well-founded definition of TIR anomaly, seems to be able to identify anomalous space-time TIR signal transients even in very variable observational (satellite view angle, land topography and coverage, etc.) and natural (e.g. meteorological) conditions. Its possible application to satellite TIR surveys in seismically active regions has been already tested in the case of several earthquakes (Irpinia: 23 November 1980, Athens: 7 September 1999, Izmit: 17 August 1999) of magnitude higher than 5.5 by using a validation/confutation approach, devoted to verify the presence/absence of anomalous space-time TIR transients in the presence/absence of seismic activity. In these cases, a magnitude threshold (generally M<5) was arbitrarily chosen in order to identify seismically unperturbed periods for confutation purposes. In this work, 9 medium-low magnitude (4earthquakes which occurred in Greece and Turkey have been analyzed in order to verify if, even in these cases, anomalous TIR transients can be observed. The analysis, which was performed using 8 years of Meteosat TIR observations, demonstrated that anomalous TIR transients can be observed even in the presence of medium-low magnitude earthquakes (4earthquake occurrence is concerned, such a result suggests

  11. Detailed crustal structure in the area of the southern Apennines-Calabrian Arc border from local earthquake tomography

    NASA Astrophysics Data System (ADS)

    Totaro, C.; Koulakov, I.; Orecchio, B.; Presti, D.

    2014-12-01

    We present a new seismic velocity model for the southern Apennines-Calabrian Arc border region with the aim to better define the crustal structures at the northern edge of the Ionian subduction zone. This sector also includes the Pollino Mts. area, where a seismic sequence of thousands of small to moderate earthquakes has been recorded between spring 2010 and 2013. In this sector a seismic gap was previously hypothesized by paleoseismological evidences associated with the lack of major earthquakes in historical catalogs. To perform the tomographic inversion we selected ca. 3600 earthquakes that have occurred in the last thirty years and recorded by permanent and temporary networks managed by INGV and Calabria University. Using for the first time the Local Tomography Software for passive tomography inversion (LOTOS hereinafter) to crustal analysis in southern Italy, we have computed the distribution of Vp, Vs, and the Vp/Vs ratio. The obtained velocity model, jointly evaluated with results of synthetic modeling, as well as with the hypocenter distribution and geological information, gives us new constraints on the geodynamical and structural knowledge of the study area. The comparison between the shallow tomography sections and surface geology shows good correlation between velocity patterns and the main geological features of the study area. In the upper crust a low-velocity anomaly of P- and S-waves is detectable beneath the Pollino Mts. area and seems to separate the Calabrian and southern Apennines domains, characterized by higher velocities. The distributions of high Vp/Vs ratio, representing strongly fractured rocks with likely high fluid content, clearly correlate with areas of significant seismicity. In the lower crust we detect a clear transition from high to low seismic velocities in correspondence with the Tyrrhenian coast of the study area, which may represent the transition from the thinner Tyrrhenian crust to the thicker one beneath Calabria. In this

  12. Studying local earthquakes in the area Baltic-Bothnia Megashear using the data of the POLENET/LAPNET temporary array

    NASA Astrophysics Data System (ADS)

    Usoltseva, Olga; Kozlovskaya, Elena

    2016-07-01

    Earthquakes in areas within continental plates are still not completely understood, and progress on understanding intraplate seismicity is slow due to a short history of instrumental seismology and sparse regional seismic networks in seismically non-active areas. However, knowledge about position and depth of seismogenic structures in such areas is necessary in order to estimate seismic hazard for such critical facilities such as nuclear power plants and nuclear waste deposits. In the present paper we address the problem of seismicity in the intraplate area of northern Fennoscandia using the information on local events recorded by the POLENET/LAPNET (Polar Earth Observing Network) temporary seismic array during the International Polar Year 2007-2009. We relocate the seismic events using the program HYPOELLIPS (a computer program for determining local earthquake hypocentral parameters) and grid search method. We use the first arrivals of P waves of local events in order to calculate a 3-D tomographic P wave velocity model of the uppermost crust (down to 20 km) for a selected region inside the study area and show that the velocity heterogeneities in the upper crust correlate well with known tectonic units. We compare the position of the velocity heterogeneities with the seismogenic structures delineated by epicentres of relocated events and demonstrate that these structures generally do not correlate with the crustal units formed as a result of crustal evolution in the Archaean and Palaeoproterozoic. On the contrary, they correlate well with the postglacial faults located in the area of the Baltic-Bothnia Megashear (BBMS). Hypocentres of local events have depths down to 30 km. We also obtain the focal mechanism of a selected event with good data quality. The focal mechanism is of oblique type with strike-slip prevailing. Our results demonstrate that the Baltic-Bothnia Megashear is an important large-scale, reactivated tectonic structure that has to be taken into

  13. Pattern recognition method applied to the forecast of strong earthquakes in South American seismic prone areas

    SciTech Connect

    Benavidez, A.

    1986-01-01

    The pattern recognition method is applied to the Andean seismic region that extends from southern latitudes 2 to 27 in the South American continent, to set a criterion for the prediction of the potential sites of strong earthquakes epicenters in the zone. It is assumed that two hypothesis hold. First, the strong earthquake epicenters typically cluster around the intersection of morphostructural lineaments. Second, the rules of recognition obtained for neighboring zones which exhibit distinctive neotectonic evolution, state of stress, spatial earthquake distribution and geological development, may be different in spite of the fact that the morphostructural zoning does not reflect a separation between them. Hence, the region is divided into two broad-scale tectonic segments located above slabs of similar scale in the Nazca plate in which subduction takes place almost subhorizontally (dipping at an angle of about 10) between latitudes 2S and 15S, and at a steeper angle (of approximately 30) within latitudes 15S to 27S. The morphostructural zoning is carried out for both zones with the determination of the lineaments and the corresponding disjunctive knots which are defined as the objects of recognition when applying the pattern recognition method. The Cora-3 algorithm is used as the computational procedure for the search of the rule of recognition of dangerous and non-dangerous sites for each zone. The set criteria contain in each case several characteristic features that represent the topography, geology and tectonics of each region. Also, it is shown that they have a physical meaning that mostly reflects the style of tectonic deformation in the related regions.

  14. The most recent large earthquake on the Rodgers Creek fault, San Francisco bay area

    USGS Publications Warehouse

    Hecker, S.; Pantosti, D.; Schwartz, D.P.; Hamilton, J.C.; Reidy, L.M.; Powers, T.J.

    2005-01-01

    The Rodgers Creek fault (RCF) is a principal component of the San Andreas fault system north of San Francisco. No evidence appears in the historical record of a large earthquake on the RCF, implying that the most recent earthquake (MRE) occurred before 1824, when a Franciscan mission was built near the fault at Sonoma, and probably before 1776, when a mission and presidio were built in San Francisco. The first appearance of nonnative pollen in the stratigraphic record at the Triangle G Ranch study site on the south-central reach of the RCF confirms that the MRE occurred before local settlement and the beginning of livestock grazing. Chronological modeling of earthquake age using radiocarbon-dated charcoal from near the top of a faulted alluvial sequence at the site indicates that the MRE occurred no earlier than A.D. 1690 and most likely occurred after A.D. 1715. With these age constraints, we know that the elapsed time since the MRE on the RCF is more than 181 years and less than 315 years and is probably between 229 and 290 years. This elapsed time is similar to published recurrence-interval estimates of 131 to 370 years (preferred value of 230 years) and 136 to 345 years (mean of 205 years), calculated from geologic data and a regional earthquake model, respectively. Importantly, then, the elapsed time may have reached or exceeded the average recurrence time for the fault. The age of the MRE on the RCF is similar to the age of prehistoric surface rupture on the northern and southern sections of the Hayward fault to the south. This suggests possible rupture scenarios that involve simultaneous rupture of the Rodgers Creek and Hayward faults. A buried channel is offset 2.2 (+ 1.2, - 0.8) m along one side of a pressure ridge at the Triangle G Ranch site. This provides a minimum estimate of right-lateral slip during the MRE at this location. Total slip at the site may be similar to, but is probably greater than, the 2 (+ 0.3, - 0.2) m measured previously at the

  15. Active Crustal Deformation in the Area of San Carlos, Baja California Sur, Mexico as Shown by Data of Local Earthquake Sequences

    NASA Astrophysics Data System (ADS)

    Munguía, Luis; González-Escobar, Mario; Navarro, Miguel; Valdez, Tito; Mayer, Sergio; Aguirre, Alfredo; Wong, Victor; Luna, Manuel

    2015-12-01

    We analyzed earthquakes of sequences that occurred at different times near San Carlos, a town of approximately 5000 inhabitants. The seismic sequences happened during March-April 1989, October 2000-June 2001, and 5-15 February 2004 at about 200 km west of the Pacific-North America plate boundary. The strong shaking from initial earthquakes of the first two sequences prompted the installation of temporary seismic stations in the area. With data recorded by these stations, we found an earthquake distribution that is consistent with the northwest segment of the Santa Margarita fault. Both the focal depth, that seemed to increase in E-NE direction, and a composite fault-plane solution, obtained from polarity data of the small earthquakes, were also consistent with the main characteristics of that fault. We also found that our normal-faulting mechanism (east side down) was quite similar to centroid moment tensor solutions for earthquakes with M w 5.4 and 5.3 that occurred in the area in February 2004. It is likely, then, that these larger earthquakes also occurred along the Santa Margarita Fault. To get some insight into the regional stress pattern, we compared the above mechanisms with mechanisms reported for other earthquakes of the Pacific margin of Baja California Sur and the Gulf of California regions. We observed that focal mechanisms of the two regions have T axes of stress that plunge sub horizontally in E-NE average direction. The corresponding P axes have N-NW average trend, but for the Pacific earthquakes these axes plunge at angles that are ~35° larger than those for the Gulf earthquakes. These more vertically inclined P axes of compressive stress mean substantial oblique fault motions. The mixture of oblique and strike-slip components of fault motions, as the focal mechanisms show, confirms a transtensional stress regime for the region. Before this research, we knew little about the seismicity and styles of faulting in the area. Now we know that

  16. Active Crustal Deformation in the Area of San Carlos, Baja California Sur, Mexico as Shown by Data of Local Earthquake Sequences

    NASA Astrophysics Data System (ADS)

    Munguía, Luis; González-Escobar, Mario; Navarro, Miguel; Valdez, Tito; Mayer, Sergio; Aguirre, Alfredo; Wong, Victor; Luna, Manuel

    2016-10-01

    We analyzed earthquakes of sequences that occurred at different times near San Carlos, a town of approximately 5000 inhabitants. The seismic sequences happened during March-April 1989, October 2000-June 2001, and 5-15 February 2004 at about 200 km west of the Pacific-North America plate boundary. The strong shaking from initial earthquakes of the first two sequences prompted the installation of temporary seismic stations in the area. With data recorded by these stations, we found an earthquake distribution that is consistent with the northwest segment of the Santa Margarita fault. Both the focal depth, that seemed to increase in E-NE direction, and a composite fault-plane solution, obtained from polarity data of the small earthquakes, were also consistent with the main characteristics of that fault. We also found that our normal-faulting mechanism (east side down) was quite similar to centroid moment tensor solutions for earthquakes with M w 5.4 and 5.3 that occurred in the area in February 2004. It is likely, then, that these larger earthquakes also occurred along the Santa Margarita Fault. To get some insight into the regional stress pattern, we compared the above mechanisms with mechanisms reported for other earthquakes of the Pacific margin of Baja California Sur and the Gulf of California regions. We observed that focal mechanisms of the two regions have T axes of stress that plunge sub horizontally in E-NE average direction. The corresponding P axes have N-NW average trend, but for the Pacific earthquakes these axes plunge at angles that are ~35° larger than those for the Gulf earthquakes. These more vertically inclined P axes of compressive stress mean substantial oblique fault motions. The mixture of oblique and strike-slip components of fault motions, as the focal mechanisms show, confirms a transtensional stress regime for the region. Before this research, we knew little about the seismicity and styles of faulting in the area. Now we know that

  17. An investigation into the socioeconomic aspects of two major earthquakes in Iran.

    PubMed

    Amini Hosseini, Kambod; Hosseinioon, Solmaz; Pooyan, Zhila

    2013-07-01

    An evaluation of the socioeconomic consequences of earthquakes is an essential part of the development of risk reduction and disaster management plans. However, these variables are not normally addressed sufficiently after strong earthquakes; researchers and relevant stakeholders focus primarily on the physical damage and casualties. The importance of the socioeconomic consequences of seismic events became clearer in Iran after the Bam earthquake on 26 December 2003, as demonstrated by the formulation and approval of various laws and ordinances. This paper reviews the country's regulatory framework in the light of the socioeconomic aspects of two major and destructive earthquakes: in Manjil-Rudbar in 1990, and in Bam in 2003. The results take the form of recommendations and practical strategies for incorporating the socioeconomic dimensions of earthquakes in disaster risk management planning. The results presented here can be applied in other countries with similar conditions to those of Iran in order to improve public preparedness and risk reduction. PMID:23551260

  18. An investigation into the socioeconomic aspects of two major earthquakes in Iran.

    PubMed

    Amini Hosseini, Kambod; Hosseinioon, Solmaz; Pooyan, Zhila

    2013-07-01

    An evaluation of the socioeconomic consequences of earthquakes is an essential part of the development of risk reduction and disaster management plans. However, these variables are not normally addressed sufficiently after strong earthquakes; researchers and relevant stakeholders focus primarily on the physical damage and casualties. The importance of the socioeconomic consequences of seismic events became clearer in Iran after the Bam earthquake on 26 December 2003, as demonstrated by the formulation and approval of various laws and ordinances. This paper reviews the country's regulatory framework in the light of the socioeconomic aspects of two major and destructive earthquakes: in Manjil-Rudbar in 1990, and in Bam in 2003. The results take the form of recommendations and practical strategies for incorporating the socioeconomic dimensions of earthquakes in disaster risk management planning. The results presented here can be applied in other countries with similar conditions to those of Iran in order to improve public preparedness and risk reduction.

  19. Estimating earthquake potential

    USGS Publications Warehouse

    Page, R.A.

    1980-01-01

    The hazards to life and property from earthquakes can be minimized in three ways. First, structures can be designed and built to resist the effects of earthquakes. Second, the location of structures and human activities can be chosen to avoid or to limit the use of areas known to be subject to serious earthquake hazards. Third, preparations for an earthquake in response to a prediction or warning can reduce the loss of life and damage to property as well as promote a rapid recovery from the disaster. The success of the first two strategies, earthquake engineering and land use planning, depends on being able to reliably estimate the earthquake potential. The key considerations in defining the potential of a region are the location, size, and character of future earthquakes and frequency of their occurrence. Both historic seismicity of the region and the geologic record are considered in evaluating earthquake potential. 

  20. 2D and 3D Visualizations of the Fault Areas, Initial Heights and Tsunami Simulations of Five Largest Historical Earthquakes in Mediterrenean Region.

    NASA Astrophysics Data System (ADS)

    Gürleme, Beran; Tarık Meriç, Hakan; Ulutaş, Ergin; Anunziato, Alessandro

    2016-04-01

    The aim of this study is the simulation and visualization of the initial and maximum tsunami wave heights in 2D and 3D along the Mediterranean coasts inferred from the five largest earthquakes in history in this region. The earthquakes considered in the study are 21 July 365 Crete, 8 August 1303 Crete, 3 May 1481 Rhodes, 28 December Messina and 21 May 2003 Algeria. All these earthquakes spawned tsunamis and inflicted damage in coastal regions. The study was conducted to explain which could be the potential Tsunami consequences caused by similar earthquakes occurring in the region in the future. The methodology used for the calculation of tsunami wave heights from the earthquakes includes the determination of earthquake parameters, modeling of the initial wave height, simulation of the wave propagation and calculation of the maximum wave heights near coastal areas. The parameters of the earthquakes are based on previously published fault mechanism solutions and known tectonic features of the regions. Static dislocation algorithm for the initial wave height is used from the parameters of focal mechanism solutions. The study was conducted also to understand the reliability of the previously published focal mechanism solutions for the earthquakes by using the principal stress axis in the regions. The 2D and 3D visualized models of tsunamis from the earthquakes include isometric grid representing the sea surface for the purpose of a better understanding of the initial tsunami mechanism compared to 1D visualizations. In many studies, the earthquake locations, tectonic features of the regions, initial heights and tsunami simulations are shown on maps as bird's eye in 1D visualization. However these kinds of features are related in depths and bathymetric features. For that reason, our approaches will contribute to have better understanding where the uplift- subsidence of initial heights and crests-troughs of simulated wave heights and thus provide a better insight of the

  1. Predicted liquefaction in the greater Oakland area and northern Santa Clara Valley during a repeat of the 1868 Hayward Fault (M6.7-7.0) earthquake

    USGS Publications Warehouse

    Holzer, Thomas L.; Noce, Thomas E.; Bennett, Michael J.

    2010-01-01

    Probabilities of surface manifestations of liquefaction due to a repeat of the 1868 (M6.7-7.0) earthquake on the southern segment of the Hayward Fault were calculated for two areas along the margin of San Francisco Bay, California: greater Oakland and the northern Santa Clara Valley. Liquefaction is predicted to be more common in the greater Oakland area than in the northern Santa Clara Valley owing to the presence of 57 km2 of susceptible sandy artificial fill. Most of the fills were placed into San Francisco Bay during the first half of the 20th century to build military bases, port facilities, and shoreline communities like Alameda and Bay Farm Island. Probabilities of liquefaction in the area underlain by this sandy artificial fill range from 0.2 to ~0.5 for a M7.0 earthquake, and decrease to 0.1 to ~0.4 for a M6.7 earthquake. In the greater Oakland area, liquefaction probabilities generally are less than 0.05 for Holocene alluvial fan deposits, which underlie most of the remaining flat-lying urban area. In the northern Santa Clara Valley for a M7.0 earthquake on the Hayward Fault and an assumed water-table depth of 1.5 m (the historically shallowest water level), liquefaction probabilities range from 0.1 to 0.2 along Coyote and Guadalupe Creeks, but are less than 0.05 elsewhere. For a M6.7 earthquake, probabilities are greater than 0.1 along Coyote Creek but decrease along Guadalupe Creek to less than 0.1. Areas with high probabilities in the Santa Clara Valley are underlain by young Holocene levee deposits along major drainages where liquefaction and lateral spreading occurred during large earthquakes in 1868 and 1906.

  2. Investigating P- and S-wave velocity structure beneath the Marmara region (Turkey) and the surrounding area from local earthquake tomography

    NASA Astrophysics Data System (ADS)

    Polat, Gulten; Özel, Nurcan Meral; Koulakov, Ivan

    2016-07-01

    We investigated the crustal structure beneath the Marmara region and the surrounding area in the western part of the North Anatolian fault zone. These areas have high seismicity and are of critical significance to earthquake hazards. The study was based on travel-time tomography using local moderate and micro-earthquakes occurring in the study area recorded by the Multi-Disciplinary Earthquake Research in High Risk Regions of Turkey project and Kandilli Observatory and Earthquake Research Institute. We selected 2131 earthquakes and a total of 92,858 arrival times, consisting of 50,044 P-wave and 42,814 S-wave arrival times. We present detailed crustal structure down to 50 km depth beneath the Marmara region for P- and S-wave velocities using the LOTOS code based on iterative inversion. We used the distributions of the resulting seismic parameters ( Vp, Vs) to pick out significant geodynamical features. The high-velocity anomalies correlate well with fracturing segments of the North Anatolian fault. High seismicity is mostly concentrated in these segments. In particular, low velocities were observed beneath the central Marmara Sea at 5 km depth.

  3. Preceding seismic activity and slow slip events in the source area of the 2011 Mw 9.0 Tohoku-Oki earthquake: a review

    NASA Astrophysics Data System (ADS)

    Hasegawa, Akira; Yoshida, Keisuke

    2015-12-01

    The 2011 Tohoku-Oki earthquake ruptured a large area of the megathrust east of NE Japan. The earthquake's magnitude was 9.0, substantially larger than predicted. It is important to know what occurred in the source area prior to this great megathrust earthquake to improve understanding of the nucleation processes of large earthquakes and risk assessments in subduction zones. Seafloor observation data revealed the existence of two extremely large slip patches: one just updip of the mainshock hypocenter and the other 80-100 km to the north near the trench axis. For 70-90 years before 2003, M > 6 events and slips of M > c. 7 events on the megathrust occurred in the areas surrounding these two large slip patches. Seismic activity had increased since at least 2003 in the downdip portion of the source area of the Tohoku-Oki earthquake. In addition, long-term accelerated slow slip occurred in this downdip portion of the source area in the decades before the Tohoku-Oki earthquake. About 1 month before the earthquake, a slow slip event (SSE) took place at relatively shallow depths between the two large slip patches, accompanied by foreshock activity. Both the slow slip and foreshocks propagated from north to south toward the southern large slip patch. Two days before the earthquake, an M 7.3 foreshock and an associated postseismic slip began at relatively deep depths in the megathrust between the two large slip patches. In addition, a slow slip type event seems to have occurred approximately half a day after the M 7.3 foreshock near the mainshock hypocenter. This slow slip event and the foreshock activity again propagated from north to south toward the mainshock hypocenter. These long- and short-term preceding seismic and aseismic slip gradually reduced the interplate coupling, increased shear stresses at the two large slip patches (i.e., two strong asperity patches), and finally led to the rupture of the great Tohoku-Oki earthquake.

  4. Heterogeneous stress field in the source area of the 2003 M6.4 Northern Miyagi Prefecture, NE Japan, earthquake

    NASA Astrophysics Data System (ADS)

    Yoshida, Keisuke; Hasegawa, Akira; Okada, Tomomi

    2016-07-01

    We investigated a detailed spatial distribution of principal stress axis orientations in the source area of the 2003 M6.4 Northern Miyagi Prefecture earthquake that occurred in the forearc of northeastern Japan. Aftershock hypocentres were precisely relocated by applying the double difference method to arrival time data obtained at temporary stations as well as at surrounding routine stations. We picked many P-wave polarity data from seismograms at these stations, which enabled us to obtain 312 well-determined focal mechanism solutions. Stress tensor inversions were performed by using these focal mechanism data. The results show that quite a lot of focal mechanisms are difficult to explain by the uniform stress field, especially near the large slip area of the main-shock rupture. Stress tensor inversions at the location of individual earthquakes show that σ1 axes are orientated mainly to WSW-ENE in the northern part of the source area, while they are oriented to NW-SE in the southern part. This spatial pattern is roughly similar to those of the static stress change by the main shock, which suggests that the observed spatially heterogeneous stress field was formed by the static stress change. If this is the case, the deviatoric stress magnitude before the main shock was very small. Another possibility is the heterogeneous stress field observed after the main shock had existed even before the main shock, although we do not know why it was formed. Unfavourable orientation of the main shock fault with respect to this stress field suggests that the fault is not strong in this case too.

  5. Three dimensional images of geothermal systems: local earthquake P-wave velocity tomography at the Hengill and Krafla geothermal areas, Iceland, and The Geysers, California

    USGS Publications Warehouse

    Julian, B.R.; Prisk, A.; Foulger, G.R.; Evans, J.R.; ,

    1993-01-01

    Local earthquake tomography - the use of earthquake signals to form a 3-dimensional structural image - is now a mature geophysical analysis method, particularly suited to the study of geothermal reservoirs, which are often seismically active and severely laterally inhomogeneous. Studies have been conducted of the Hengill (Iceland), Krafla (Iceland) and The Geysers (California) geothermal areas. All three systems are exploited for electricity and/or heat production, and all are highly seismically active. Tomographic studies of volumes a few km in dimension were conducted for each area using the method of Thurber (1983).

  6. β-amylase 1 (BAM1) degrades transitory starch to sustain proline biosynthesis during drought stress.

    PubMed

    Zanella, Martina; Borghi, Gian Luca; Pirone, Claudia; Thalmann, Matthias; Pazmino, Diana; Costa, Alex; Santelia, Diana; Trost, Paolo; Sparla, Francesca

    2016-03-01

    During photosynthesis of higher plants, absorbed light energy is converted into chemical energy that, in part, is accumulated in the form of transitory starch within chloroplasts. In the following night, transitory starch is mobilized to sustain the heterotrophic metabolism of the plant. β-amylases are glucan hydrolases that cleave α-1,4-glycosidic bonds of starch and release maltose units from the non-reducing end of the polysaccharide chain. In Arabidopsis, nocturnal degradation of transitory starch involves mainly β-amylase-3 (BAM3). A second β-amylase isoform, β-amylase-1 (BAM1), is involved in diurnal starch degradation in guard cells, a process that sustains stomata opening. However, BAM1 also contributes to diurnal starch turnover in mesophyll cells under osmotic stress. With the aim of dissecting the role of β-amylases in osmotic stress responses in Arabidopsis, mutant plants lacking either BAM1 or BAM3 were subject to a mild (150mM mannitol) and prolonged (up to one week) osmotic stress. We show here that leaves of osmotically-stressed bam1 plants accumulated more starch and fewer soluble sugars than both wild-type and bam3 plants during the day. Moreover, bam1 mutants were impaired in proline accumulation and suffered from stronger lipid peroxidation, compared with both wild-type and bam3 plants. Taken together, these data strongly suggest that carbon skeletons deriving from BAM1 diurnal degradation of transitory starch support the biosynthesis of proline required to face the osmotic stress. We propose the transitory-starch/proline interplay as an interesting trait to be tackled by breeding technologies aimingto improve drought tolerance in relevant crops. PMID:26792489

  7. Potential for larger earthquakes in the East San Francisco Bay Area due to the direct connection between the Hayward and Calaveras Faults

    NASA Astrophysics Data System (ADS)

    Chaussard, E.; Bürgmann, R.; Fattahi, H.; Nadeau, R. M.; Taira, T.; Johnson, C. W.; Johanson, I.

    2015-04-01

    The Hayward and Calaveras Faults, two strike-slip faults of the San Andreas System located in the East San Francisco Bay Area, are commonly considered independent structures for seismic hazard assessment. We use Interferometric Synthetic Aperture RADAR to show that surface creep on the Hayward Fault continues 15 km farther south than previously known, revealing new potential for rupture and damage south of Fremont. The extended trace of the Hayward Fault, also illuminated by shallow repeating micro-earthquakes, documents a surface connection with the Calaveras Fault. At depths greater than 3-5 km, repeating micro-earthquakes located 10 km north of the surface connection highlight the 3-D wedge geometry of the junction. Our new model of the Hayward and Calaveras Faults argues that they should be treated as a single system with potential for earthquake ruptures generating events with magnitudes greater than 7, posing a higher seismic hazard to the East San Francisco Bay Area than previously considered.

  8. Geologic and tectonic setting of the epicentral area of the Loma Prieta earthquake, Santa Cruz County, California

    SciTech Connect

    Wagner, D.L.

    1990-11-01

    Although shaking from the magnitude 7.1 October 17, 1989 Loma Prieta quake lasted only about 15 seconds, the temblor resulted in 67 deaths, more than 3,500 people injured, and property damage estimated at $7.5 billion, it was felt over an area of about 400,000 square miles and caused the biggest dollar loss of any natural disaster in US history. The following article was originally published in the Division of Mines and Geology Special Publication 104 and describes the regional geology of this catastrophic quake. Such detailed investigations of earthquake processes aid in our understanding of how, where - and hopefully - when they will happen in the future.

  9. Interaction of methionine-enkephalins with raft-forming lipids: monolayers and BAM experiments.

    PubMed

    Tsanova, A; Jordanova, A; Dzimbova, T; Pajpanova, T; Golovinsky, E; Lalchev, Z

    2014-05-01

    Enkephalins (Tyr-Gly-Gly-Phe-Met/Leu) are opioid peptides with proven antinociceptive action in organism. They interact with opioid receptors belonging to G-protein coupled receptor superfamily. It is known that these receptors are located preferably in membrane rafts composed mainly of sphingomyelin (Sm), cholesterol (Cho), and phosphatidylcholine. In the present work, using Langmuir's monolayer technique in combination with Wilhelmy's method for measuring the surface pressure, the interaction of synthetic methionine-enkephalin and its amidated derivative with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), Sm, and Cho, as well as with their double and triple mixtures, was studied. From the pressure/area isotherms measured, the compressional moduli of the lipids and lipid-peptide monolayers were determined. Our results showed that the addition of the synthetic enkephalins to the monolayers studied led to change in the lipid monolayers characteristics, which was more evident in enkephalinamide case. In addition, using Brewster angle microscopy (BAM), the surface morphology of the lipid monolayers, before and after the injection of both enkephalins, was determined. The BAM images showed an increase in surface density of the mixed surface lipids/enkephalins films, especially with double and triple component lipid mixtures. This effect was more pronounced for the enkephalinamide as well. These observations showed that there was an interaction between the peptides and the raft-forming lipids, which was stronger for the amidated peptide, suggesting a difference in folding of both enkephalins. Our research demonstrates the potential of lipid monolayers for elegant and simple membrane models to study lipid-peptide interactions at the plane of biomembranes.

  10. Shallow earthquake swarms in southern Ryukyu area: manifestation of dynamics of fluid and/or magma plumbing system revealed by teleseismic and regional datasets

    NASA Astrophysics Data System (ADS)

    Špičák, Aleš; Vaněk, Jiří

    2016-06-01

    Earthquake swarm occurrence beneath volcanic domains is one of the indicators of current magmatic activity in the Earth's crust. Repeated occurrence of teleseismically recorded earthquake swarms has been observed in the lithospheric wedge of the southern Ryukyu area above the subducting slab of the Philippine Sea Plate. The swarms were analyzed using the EHB, ISC and JMA catalogs of hypocenter parameters. The swarm earthquakes are shallow (1-60 km), in the body-wave magnitude range up to 5.8. The swarms are distributed beneath the seafloor, parallel to the Ryukyu Trench along a belt connecting active subaerial volcanoes Io-Torishima north-east and Kueishantao west of the investigated area. Epicentral zones of the swarms often coincide with distinct elevations at the seafloor—seamounts and seamount ranges. The top of the subducting slab reaches a depth of about 100 km beneath the zones of earthquake swarm occurrence, which is an average depth of a slab beneath volcanoes in general. The repeated occurrence of relatively strong, teleseismically recorded earthquake swarms thus probably reflects fluid and/or magma migration in the plumbing system of the volcanic arc and points to brittle character of the lithospheric wedge at respective depths. In addition to the factual results, this study documents the high accuracy of hypocenter parameter determinations published by the International Seismological Centre and the usefulness of the EHB relocation procedure.

  11. LLNL Small-Scale Friction sensitivity (BAM) Test

    SciTech Connect

    Simpson, L.R.; Foltz, M.F.

    1996-06-01

    Small-scale safety testing of explosives, propellants and other energetic materials, is done to determine their sensitivity to various stimuli including friction, static spark, and impact. Testing is done to discover potential handling problems for either newly synthesized materials of unknown behavior, or materials that have been stored for long periods of time. This report describes the existing {open_quotes}BAM{close_quotes} Small-Scale Friction Test, and the methods used to determine the friction sensitivity pertinent to handling energetic materials. The accumulated data for the materials tested is not listed here - that information is in a database. Included is, however, a short list of (1) materials that had an unusual response, and (2), a few {open_quotes}standard{close_quotes} materials representing the range of typical responses usually seen.

  12. BAM: A metrology device for a high precision astrometric mission

    NASA Astrophysics Data System (ADS)

    Riva, A.; Gai, M.; Lattanzi, M. G.; Russo, F.; Buzzi, R.

    2014-12-01

    Gaia is ESA next-generation astrometric space mission, that will be launched in December 2013. The main objective of Gaia is to produce an astrometric census of one billion objects down to the 20th magnitude. The level of astrometric precision will be around the 10 microarcseconds. In order to achieve such demanding performances, the complexity of the satellite is huge, and a proper fully automated operation must be adopted. One of the essential parts of the satellite is the BAM instrument, an interferometric device with the task of monitoring the variation of the Basic Angle between the two telescope that compose the payload. In this paper we describe the main features of this sub-instrument and its performances.

  13. The ratio of injured to fatalities in earthquakes, estimated from intensity and building properties

    NASA Astrophysics Data System (ADS)

    Wyss, M.; Trendafiloski, G.

    2009-04-01

    a city with poorly constructed buildings. The over all ratio for Bam was R=0.33 and for three districts it was R=0.2. In the only other city in the epicentral area, Baravat, located within about four kilometers of the epicenter R=0.55. Our contention that R is a function of I is further supported by analyzing R(I) for earthquakes where R is known for several settlements. The uncertainties in input parameters like earthquake source properties and Fat are moderate, those in Inj are large. Nevertheless our results are robust because the difference between R in the developed and developing world is enormous and the dependence on I is obvious. We conclude that R in most earthquakes results from a mixture of low values near the epicenter and high values farther away where intensities decrease to VI. The range between settlements in one single earthquake can be approximately 0.2 < R < 100, due to varying distance and hence varying I. Further, R(developed) = 25 R(developing), approximately. We also simulated several past earthquakes in Algeria, Peru and Iran to compare the values of estimated R(I) resulting from the use of ATC-13 and HAZUS casualty matrices with observations. We evaluated these matrices because they are supposed to apply worldwide and they consider all damage states as possible cause of casualties. Our initial conclusion is that the later matrices fit the observations better, in particular for intensity range VII-IX. However, to improve the estimates for all intensity values, we propose that casualty matrices for estimating human losses due to earthquakes should account for differences in I and in the building quality in different parts of the world.

  14. Large-scale aseismic creep in the areas of the strong earthquakes revealed from the GRACE data on the time variations of the Earth's gravity field

    NASA Astrophysics Data System (ADS)

    Mikhailov, V. O.; Diament, M.; Lyubushin, A. A.; Timoshkina, E. P.; Khairetdinov, S. A.

    2016-09-01

    ruptured fault plane zone. The data demonstrating the increasing depth of the aftershocks since March 2007 and the approximately simultaneous change in the direction and average velocity of the horizontal surface displacements at the sites of the regional GPS network indicate that this earthquake induced postseismic displacements in a huge area extending to depths below 100 km. The total displacement since the beginning of the growth of the gravity anomaly up to July 2012 is estimated at 3.0 m in the upper part of the plate's contact and 1.5 m in the lower part up to a depth of 100 km. With allowance for the size of the region captured by the deformations, the released total energy is equivalent to the earthquake with the magnitude M w = 8.5. In our opinion, the growth of the gravity anomaly in these regions indicates a large-scale aseismic creep over the areas much more extensive than the source zone of the earthquake. These processes have not been previously revealed by the ground-based techniques. Hence, the time series of the GRACE gravity models are an important source of the new data about the locations and evolution of the locked segments of the subduction zones and their seismic potential.

  15. Rapid Assessment of Earthquakes with Radar and Optical Geodetic Imaging and Finite Fault Models (Invited)

    NASA Astrophysics Data System (ADS)

    Fielding, E. J.; Sladen, A.; Simons, M.; Rosen, P. A.; Yun, S.; Li, Z.; Avouac, J.; Leprince, S.

    2010-12-01

    Earthquake responders need to know where the earthquake 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 earthquake hypocenter and moment tensor centroid and also the locations of aftershocks. Location accuracy depends on the availability of seismic data close to the earthquake source. Finite fault models of the earthquake 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 earthquakes, 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 earthquakes, 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 models. In many of these cases, the fault ruptures were on previously unknown faults or faults not believed to be at high risk of earthquakes, so the area and degree of

  16. Impact of the 2001 Tohoku-oki earthquake to Tokyo Metropolitan area observed by the Metropolitan Seismic Observation network (MeSO-net)

    NASA Astrophysics Data System (ADS)

    Hirata, N.; Hayashi, H.; Nakagawa, S.; Sakai, S.; Honda, R.; Kasahara, K.; Obara, K.; Aketagawa, T.; Kimura, H.; Sato, H.; Okaya, D. A.

    2011-12-01

    The March 11, 2011 Tohoku-oki earthquake brought a great impact to the Tokyo metropolitan area in both seismological aspect and seismic risk management although Tokyo is located 340 km from the epicenter. The event generated very strong ground motion even in the metropolitan area and resulted severe requifaction in many places of Kanto district. National and local governments have started to discuss counter measurement for possible seismic risks in the area taking account for what they learned from the Tohoku-oki event which is much larger than ever experienced in Japan Risk mitigation strategy for the next greater earthquake caused by the Philippine Sea plate (PSP) subducting beneath the Tokyo metropolitan area is of major concern because it caused past mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9). An M7 or greater (M7+) earthquake in this area at present has high potential to produce devastating loss of life and property with even greater global economic repercussions. The Central Disaster Management Council of Japan estimates that an M7+ earthquake will cause 11,000 fatalities and 112 trillion yen (about 1 trillion US$) economic loss. In order to mitigate disaster for greater Tokyo, the Special Project for Earthquake Disaster Mitigation in the Tokyo Metropolitan Area was launched in collaboration with scientists, engineers, and social-scientists in nationwide institutions. We will discuss the main results that are obtained in the respective fields which have been integrated to improve information on the strategy assessment for seismic risk mitigation in the Tokyo metropolitan area; the project has been much improved after the Tohoku event. In order to image seismic structure beneath the Metropolitan Tokyo area we have developed Metropolitan Seismic Observation network (MeSO-net; Hirata et al., 2009). We have installed 296 seismic stations every few km (Kasahara et al., 2011). We conducted seismic

  17. Propagation mechanisms of incident tsunami wave in Jiangsu coastal area, caused by eastern Japan earthquake on March 11, 2011

    NASA Astrophysics Data System (ADS)

    Yuan, Chun-guang; Wang, Yi-gang; Huang, Hui-ming; Chen, Cheng; Chen, Da-ke

    2016-03-01

    At 13:46 on March 11, 2011 (Beijing time), an earthquake of Mw=9.0 occurred in Japan. By comparing the tsunami data from Guanhekou marine station with other tsunami wave observation gathered from southeast coastal area of China, it was evident that, only in Guanhekou, the position of the maximum wave height appeared in the middle part rather than in the front of the tsunami wave train. A numerical model of tsunami propagation based on 2-D nonlinear shallow water equations was built to study the impact range and main causes of the special tsunami waveform discovered in Jiangsu coastal area. The results showed that nearly three-quarters of the Jiangsu coastal area, mainly comprised the part north of the radial sand ridges, reached its maximum tsunami wave height in the middle part of the wave train. The main cause of the special waveform was the special underwater topography condition of the Yellow Sea and the East China Sea area, which influenced the tsunami propagation and waveform significantly. Although land boundary reflection brought an effect on the position of the maximum wave height to a certain extent, as the limits of the incident waveform and distances between the observation points and shore, it was not the dominant influence factor of the special waveform. Coriolis force's impact on the tsunami waves was so weak that it was not the main cause for the special phenomenon in Jiangsu coastal area. The study reminds us that the most destructive wave might not appear in the first one in tsunami wave train.

  18. Seismic characterization of the j-reflector near the meizoseismal area of the 1886 Charleston earthquake for lithologic constraint

    NASA Astrophysics Data System (ADS)

    Cunningham, Craig

    Investigations into the relationship between geologic structure and seismicity in and around the meizoseismal area of the 1886 Charleston earthquake have been ongoing since the 1970s. Seismic reflection profiles collected in this area display a prominent, laterally continuous, high amplitude, low frequency, two cycle reflection at ~0.7-1.2 s TWT, termed the "J" reflector, which has been correlated with Lower to Middle Jurassic tholeiitic basalt flows encountered in the Clubhouse Crossroads wells. The "J" reflector was also extended offshore onto the continental shelf. Recent reevaluation of sub Coastal Plain wells within the South Georgia Rift (SGR) Basin, including wells around the meizoseismal area of the 1886 Charleston earthquake, has shown most do not encounter basalt rising suspicions as to the true lithology of the "J"-reflector. Moreover, this same reflector has been interpreted to be the unconformity at the base of the Cretaceous-age Coastal Plain sediments. In order to define the regional extent of the Clubhouse Crossroads basalt, seismic inversion and attribute analysis were performed on two recently acquired reflection profiles, SC02_1 and SC02_5. Beginning in December 2010 through February 2011, seven 2D reflection profiles: SC02_1 - SC02_7 (total length 240 km) were acquired to the immediate west and northwest of the Charleston meizoseismal zone and legacy seismic data as part of DOE Award DE-FE0001965: Geologic Characterization of the South Georgia Rift Basin for Source Proximal C02 Storage project. The first profile, SC02_1, passes Norris Lightsey #1 and Rizer #1, two wells that never encountered basalt at the base of coastal plain. SC02_5, passes Dorchester 211, a well that bottomed into basalt at the base of the coastal plain. Variations in seismic attributes provides evidence for a western termination of the clubhouse crossroads basalt flow on SC02_1 and key support for visible amplitude variations at the contact between coastal plain

  19. Post-traumatic psychological changes among survivors of the Lushan earthquake living in the most affected areas.

    PubMed

    Tang, Bihan; Kang, Peng; Liu, Xu; Liu, Yuan; Liu, Zhipeng; Wang, Bowen; Lv, Yipeng; Zhang, Lulu

    2014-12-15

    The primary objective of our study was to investigate both the negative and positive psychological changes following the Lushan earthquake, and to explore the factors associated with psychological changes. Multi-stage random sampling was used to select respondents from Lushan County, Sichuan Province, China. A simplified Chinese version of the short form of Changes in Outlook Questionnaire (CiOQ-S) was used to assess psychological changes in earthquake survivors. Descriptive statistics, t-tests, ANOVA and stepwise linear regression analysis were used for data analysis. A total of 4972 respondents were investigated in the cross-sectional study. The mean scores of the positive and negative psychological changes were 26.61 and 8.12, respectively. The factors associated with positive psychological changes included ethnic minority, high level of education, high household income, not injured in the earthquake, not trapped during the earthquake, and having experienced the Wenchuan earthquake. The factors associated with negative psychological changes included female gender, ethnic minority, low household income, history of diseases, injured during the earthquake, and trapped during the earthquake. The current analysis helps expand our knowledge of the negative and positive psychological changes that may occur following an earthquake experience.

  20. The population in China’s earthquake-prone areas has increased by over 32 million along with rapid urbanization

    NASA Astrophysics Data System (ADS)

    He, Chunyang; Huang, Qingxu; Dou, Yinyin; Tu, Wei; Liu, Jifu

    2016-07-01

    Accurate assessments of the population exposed to seismic hazard are crucial in seismic risk mapping. Recent rapid urbanization in China has resulted in substantial changes in the size and structure of the population exposed to seismic hazard. Using the latest population census data and seismic maps, this work investigated spatiotemporal changes in the exposure of the population in the most seismically hazardous areas (MSHAs) in China from 1990 to 2010. In the context of rapid urbanization and massive rural-to-urban migration, nearly one-tenth of the Chinese population in 2010 lived in MSHAs. From 1990 to 2010, the MSHA population increased by 32.53 million at a significantly higher rate of change (33.6%) than the national average rate (17.7%). The elderly population in MSHAs increased by 81.4%, which is much higher than the group’s national growth rate of 58.9%. Greater attention should be paid to the demographic changes in earthquake-prone areas in China.

  1. biobambam: tools for read pair collation based algorithms on BAM files

    PubMed Central

    2014-01-01

    Background Sequence alignment data is often ordered by coordinate (id of the reference sequence plus position on the sequence where the fragment was mapped) when stored in BAM files, as this simplifies the extraction of variants between the mapped data and the reference or of variants within the mapped data. In this order paired reads are usually separated in the file, which complicates some other applications like duplicate marking or conversion to the FastQ format which require to access the full information of the pairs. Results In this paper we introduce biobambam, a set of tools based on the efficient collation of alignments in BAM files by read name. The employed collation algorithm avoids time and space consuming sorting of alignments by read name where this is possible without using more than a specified amount of main memory. Using this algorithm tasks like duplicate marking in BAM files and conversion of BAM files to the FastQ format can be performed very efficiently with limited resources. We also make the collation algorithm available in the form of an API for other projects. This API is part of the libmaus package. Conclusions In comparison with previous approaches to problems involving the collation of alignments by read name like the BAM to FastQ or duplication marking utilities our approach can often perform an equivalent task more efficiently in terms of the required main memory and run-time. Our BAM to FastQ conversion is faster than all widely known alternatives including Picard and bamUtil. Our duplicate marking is about as fast as the closest competitor bamUtil for small data sets and faster than all known alternatives on large and complex data sets.

  2. Application of a bi-directional associative memory (BAM) network in computer assisted learning in chemistry.

    PubMed

    Chau, F T; Cheung, B; Tam, K Y; Li, L K

    1994-12-01

    A computer assisted learning software based on a bi-directional associative memory (BAM) network was developed. The software was implemented to assist students in associating the names of the elements in the periodic table with their chemical symbols. The use of the BAM facilitates the analysis and interpretation of students' responses. The software package can be modified easily as an educational tool for other disciplines. PMID:7812638

  3. Structure of BamA, an essential factor in outer membrane protein biogenesis.

    PubMed

    Albrecht, Reinhard; Schütz, Monika; Oberhettinger, Philipp; Faulstich, Michaela; Bermejo, Ivan; Rudel, Thomas; Diederichs, Kay; Zeth, Kornelius

    2014-06-01

    Outer membrane protein (OMP) biogenesis is an essential process for maintaining the bacterial cell envelope and involves the β-barrel assembly machinery (BAM) for OMP recognition, folding and assembly. In Escherichia coli this function is orchestrated by five proteins: the integral outer membrane protein BamA of the Omp85 superfamily and four associated lipoproteins. To unravel the mechanism underlying OMP folding and insertion, the structure of the E. coli BamA β-barrel and P5 domain was determined at 3 Å resolution. These data add information beyond that provided in the recently published crystal structures of BamA from Haemophilus ducreyi and Neisseria gonorrhoeae and are a valuable basis for the interpretation of pertinent functional studies. In an `open' conformation, E. coli BamA displays a significant degree of flexibility between P5 and the barrel domain, which is indicative of a multi-state function in substrate transfer. E. coli BamA is characterized by a discontinuous β-barrel with impaired β1-β16 strand interactions denoted by only two connecting hydrogen bonds and a disordered C-terminus. The 16-stranded barrel surrounds a large cavity which implies a function in OMP substrate binding and partial folding. These findings strongly support a mechanism of OMP biogenesis in which substrates are partially folded inside the barrel cavity and are subsequently released laterally into the lipid bilayer. PMID:24914988

  4. Earthquake history of Oregon

    USGS Publications Warehouse

    von Hake, C. A.

    1976-01-01

    Although situated between two States (California and Washington) that have has many violent earthquakes, Oregon is noticeably less active seismically. the greatest damage experienced resulted from a major shock near Olympia, Wash., in 1949. During the short history record available (since 1841), 34 earthquakes of intensity V, Modified Mercalli Scale, or greater have centered within Oregon or near its borders. Only 13 of the earthquakes had an intensity above V, and many of the shocks were local. However, a 1936 earthquake in the eastern Oregon-Washington region caused extensive damage and was felt over an area of 272,000 square kilometers. 

  5. Seismic structure beneath the Gulf of Aqaba and adjacent areas based on the tomographic inversion of regional earthquake data

    NASA Astrophysics Data System (ADS)

    El Khrepy, Sami; Koulakov, Ivan; Al-Arifi, Nassir; Petrunin, Alexey G.

    2016-06-01

    We present the first 3-D model of seismic P and S velocities in the crust and uppermost mantle beneath the Gulf of Aqaba and surrounding areas based on the results of passive travel time tomography. The tomographic inversion was performed based on travel time data from ˜ 9000 regional earthquakes provided by the Egyptian National Seismological Network (ENSN), and this was complemented with data from the International Seismological Centre (ISC). The resulting P and S velocity patterns were generally consistent with each other at all depths. Beneath the northern part of the Red Sea, we observed a strong high-velocity anomaly with abrupt limits that coincide with the coastal lines. This finding may indicate the oceanic nature of the crust in the Red Sea, and it does not support the concept of gradual stretching of the continental crust. According to our results, in the middle and lower crust, the seismic anomalies beneath the Gulf of Aqaba seem to delineate a sinistral shift (˜ 100 km) in the opposite flanks of the fault zone, which is consistent with other estimates of the left-lateral displacement in the southern part of the Dead Sea Transform fault. However, no displacement structures were visible in the uppermost lithospheric mantle.

  6. Lightning Activities and Earthquakes

    NASA Astrophysics Data System (ADS)

    Liu, Jann-Yenq

    2016-04-01

    The lightning activity is one of the key parameters to understand the atmospheric electric fields and/or currents near the Earth's surface as well as the lithosphere-atmosphere coupling during the earthquake preparation period. In this study, to see whether or not lightning activities are related to earthquakes, we statistically examine lightning activities 30 days before and after 78 land and 230 sea M>5.0 earthquakes in Taiwan during the 12-year period of 1993-2004. Lightning activities versus the location, depth, and magnitude of earthquakes are investigated. Results show that lightning activities tend to appear around the forthcoming epicenter and are significantly enhanced a few, especially 17-19, days before the M>6.0 shallow (depth D< 20 km) land earthquakes. Moreover, the size of the area around the epicenter with the statistical significance of lightning activity enhancement is proportional to the earthquake magnitude.

  7. Detection of shallow crustal discontinuities from high frequency waveforms of swarm earthquakes in West Bohemia/Vogtland seismoactive area

    NASA Astrophysics Data System (ADS)

    Hrubcová, Pavla; Vavryčuk, Václav; Boušková, Alena

    2015-04-01

    The western part of the Bohemian Massif, the West Bohemia/Vogtland region, is the area of the increased geodynamic activity manifested by repeated occurrence of intraplate earthquake swarms and fluid degassing. To understand geodynamic processes, knowledge of a detailed crustal structure is essential for all advanced studies of seismicity and focal parameters of the micro-earthquake swarms that occur in this region. The crustal structure is usually inferred from active seismic investigations, i.e., reflection and refraction seismic imaging. Passive seismic investigation focused on swarm microearthquakes has an advantage over the active exploration. The microseismic investigation typically handles large amount of data ideal for stacking, foci are usually far from the shallowest structure so waveforms are rather simple, and data acquisition is not expensive. The standard microseismic monitoring of swarms is prevalently used for retrieving information on seismic source parameters, such as magnitude, location, seismic moment, and moment tensors. However, high-frequency seismic waves generated by local sources are sensitive to sharp changes in velocities or density and the structure can be determined from reflected and converted phases secondarily originating at deep and shallow subsurface layers. In our study we concentrate on the velocity distribution in the upper crust. The upper crustal structure is studied from waveforms of local microearthquakes that occurred during the 2008 swarm in West Bohemia/Vogtland seismoactive region. They were recorded by the WEBNET network consisting of 22 three-component seismic stations. We focus on high-frequency PS and SP converted waves generated at shallow interfaces at depths between 2 and 5 km. Apart from velocity contrast at the interfaces, the amplitudes of converted waves are significantly affected by source-receiver geometry and focal mechanisms of the earthquakes. This observation complicates the analysis, being absent in

  8. Reactivated faulting near Cushing, Oklahoma: Increased potential for a triggered earthquake in an area of United States strategic infrastructure

    USGS Publications Warehouse

    McNamara, Daniel E.; Hayes, Gavin; Benz, Harley M.; Williams, Robert; McMahon, Nicole D; Aster, R.C.; Holland, Austin F.; Sickbert, T; Herrmann, Robert B.; Briggs, Richard; Smoczyk, Gregory M.; Bergman, Eric; Earle, Paul

    2015-01-01

    In October 2014 two moderate-sized earthquakes (Mw 4.0 and 4.3) struck south of Cushing, Oklahoma, below the largest crude oil storage facility in the world. Combined analysis of the spatial distribution of earthquakes and regional moment tensor focal mechanisms indicate reactivation of a subsurface unnamed and unmapped left-lateral strike-slip fault. Coulomb failure stress change calculations using the relocated seismicity and slip distribution determined from regional moment tensors, allow for the possibility that the Wilzetta-Whitetail fault zone south of Cushing, Oklahoma, could produce a large, damaging earthquake comparable to the 2011 Prague event. Resultant very strong shaking levels (MMI VII) in the epicentral region present the possibility of this potential earthquake causing moderate to heavy damage to national strategic infrastructure and local communities.

  9. Reactivated faulting near Cushing, Oklahoma: Increased potential for a triggered earthquake in an area of United States strategic infrastructure

    NASA Astrophysics Data System (ADS)

    McNamara, D. E.; Hayes, G. P.; Benz, H. M.; Williams, R. A.; McMahon, N. D.; Aster, R. C.; Holland, A.; Sickbert, T.; Herrmann, R.; Briggs, R.; Smoczyk, G.; Bergman, E.; Earle, P.

    2015-10-01

    In October 2014 two moderate-sized earthquakes (Mw 4.0 and 4.3) struck south of Cushing, Oklahoma, below the largest crude oil storage facility in the world. Combined analysis of the spatial distribution of earthquakes and regional moment tensor focal mechanisms indicate reactivation of a subsurface unnamed and unmapped left-lateral strike-slip fault. Coulomb failure stress change calculations using the relocated seismicity and slip distribution determined from regional moment tensors, allow for the possibility that the Wilzetta-Whitetail fault zone south of Cushing, Oklahoma, could produce a large, damaging earthquake comparable to the 2011 Prague event. Resultant very strong shaking levels (MMI VII) in the epicentral region present the possibility of this potential earthquake causing moderate to heavy damage to national strategic infrastructure and local communities.

  10. Construction and operation of a system for secure and precise medical material distribution in disaster areas after Wenchuan earthquake.

    PubMed

    Cheng, Yongzhong; Xu, Jiankang; Ma, Jian; Cheng, Shusen; Shi, Yingkang

    2009-11-01

    After the Wenchuan Earthquake on May 12th , 2008, under the strong leadership of the Sichuan Provincial Party Committee, the People's Government of Sichuan Province, and the Ministry of Health of the People's Republic of China, the Medical Security Team working at the Sichuan Provincial Headquarters for Wenchuan Earthquake and Disaster Relief Work constructed a secure medical material distribution system through coordination and interaction among and between regions, systems, and departments.

  11. Uncertainty of earthquake losses due to model uncertainty of input ground motions in the Los Angeles area

    USGS Publications Warehouse

    Cao, T.; Petersen, M.D.

    2006-01-01

    In a recent study we used the Monte Carlo simulation method to evaluate the ground-motion uncertainty of the 2002 update of the California probabilistic seismic hazard model. The resulting ground-motion distribution is used in this article to evaluate the contribution of the hazard model to the uncertainty in earthquake loss ratio, the ratio of the expected loss to the total value of a structure. We use the Hazards U.S. (HAZUS) methodology for loss estimation because it is a widely used and publicly available risk model and intended for regional studies by public agencies and for use by governmental decision makers. We found that the loss ratio uncertainty depends not only on the ground-motion uncertainty but also on the mean ground-motion level. The ground-motion uncertainty, as measured by the coefficient of variation (COV), is amplified when converting to the loss ratio uncertainty because loss increases concavely with ground motion. By comparing the ground-motion uncertainty with the corresponding loss ratio uncertainty for the structural damage of light wood-frame buildings in Los Angeles area, we show that the COV of loss ratio is almost twice the COV of ground motion with a return period of 475 years around the San Andreas fault and other major faults in the area. The loss ratio for the 2475-year ground-motion maps is about a factor of three higher than for the 475-year maps. However, the uncertainties in ground motion and loss ratio for the longer return periods are lower than for the shorter return periods because the uncertainty parameters in the hazard logic tree are independent of the return period, but the mean ground motion increases with return period.

  12. Waveform through the subducted plate under the Tokyo region in Japan observed by a ultra-dense seismic network (MeSO-net) and seismic activity around mega-thrust earthquakes area

    NASA Astrophysics Data System (ADS)

    Sakai, S.; Kasahara, K.; Nanjo, K.; Nakagawa, S.; Tsuruoka, H.; Morita, Y.; Kato, A.; Iidaka, T.; Hirata, N.; Tanada, T.; Obara, K.; Sekine, S.; Kurashimo, E.

    2009-12-01

    In central Japan, the Philippine Sea plate (PSP) subducts beneath the Tokyo Metropolitan area, the Kanto region, where it causes mega-thrust earthquakes, such as the 1703 Genroku earthquake (M8.0) and the 1923 Kanto earthquake (M7.9) which had 105,000 fatalities. A M7 or greater earthquake in this region at present has high potential to produce devastating loss of life and property with even greater global economic repercussions. The Central Disaster Management Council of Japan estimates the next great earthquake will cause 11,000 fatalities and 112 trillion yen (1 trillion US$) economic loss. This great earthquake is evaluated to occur with a probability of 70 % in 30 years by the Earthquake Research Committee of Japan. We had started the Special Project for Earthquake Disaster Mitigation in Tokyo Metropolitan area (2007-2012). Under this project, the construction of the Metropolitan Seismic Observation network (MeSO-net) that consists of about 400 observation sites was started [Kasahara et al., 2008; Nakagawa et al., 2008]. Now, we had 178 observation sites. The correlation of the wave is high because the observation point is deployed at about 2 km intervals, and the identification of the later phase is recognized easily thought artificial noise is very large. We also discuss the relation between a deformation of PSP and intra-plate M7+ earthquakes: the PSP is subducting beneath the Honshu arc and also colliding with the Pacific plate. The subduction and collision both contribute active seismicity in the Kanto region. We are going to present a high resolution tomographic image to show low velocity zone which suggests a possible internal failure of the plate; a source region of the M7+ intra-plate earthquake. Our study will contribute a new assessment of the seismic hazard at the Metropolitan area in Japan. Acknowledgement: This study was supported by the Earthquake Research Institute cooperative research program.

  13. Winnetka deformation zone: Surface expression of coactive slip on a blind fault during the Northridge earthquake sequence, California. Evidence that coactive faulting occurred in the Canoga Park, Winnetka, and Northridge areas during the 17 January 1994, Northridge, California earthquake

    SciTech Connect

    Cruikshank, K.M.; Johnson, A.M.; Fleming, R.W.; Jones, R.L.

    1996-12-31

    Measurements of normalized length changes of streets over an area of 9 km{sup 2} in San Fernando Valley of Los Angeles, California, define a distinctive strain pattern that may well reflect blind faulting during the 1994 Northridge earthquake. Strain magnitudes are about 3 {times} 10{sup {minus}4}, locally 10{sup {minus}3}. They define a deformation zone trending diagonally from near Canoga Park in the southwest, through Winnetka, to near Northridge in the northeast. The deformation zone is about 4.5 km long and 1 km wide. The northwestern two-thirds of the zone is a belt of extension of streets, and the southeastern one-third is a belt of shortening of streets. On the northwest and southeast sides of the deformation zone the magnitude of the strains is too small to measure, less than 10{sup {minus}4}. Complete states of strain measured in the northeastern half of the deformation zone show that the directions of principal strains are parallel and normal to the walls of the zone, so the zone is not a strike-slip zone. The magnitudes of strains measured in the northeastern part of the Winnetka area were large enough to fracture concrete and soils, and the area of larger strains correlates with the area of greater damage to such roads and sidewalks. All parts of the pattern suggest a blind fault at depth, most likely a reverse fault dipping northwest but possibly a normal fault dipping southeast. The magnitudes of the strains in the Winnetka area are consistent with the strains produced at the ground surface by a blind fault plane extending to depth on the order of 2 km and a net slip on the order of 1 m, within a distance of about 100 to 500 m of the ground surface. The pattern of damage in the San Fernando Valley suggests a fault segment much longer than the 4.5 km defined by survey data in the Winnetka area. The blind fault segment may extend several kilometers in both directions beyond the Winnetka area. This study of the Winnetka area further supports

  14. Earthquakes; January-February, 1979

    USGS Publications Warehouse

    Person, W.J.

    1979-01-01

    The first major earthquake (magnitude 7.0 to 7.9) of the year struck in southeastern Alaska in a sparsely populated area on February 28. On January 16, Iran experienced the first destructive earthquake of the year causing a number of casualties and considerable damage. Peru was hit by a destructive earthquake on February 16 that left casualties and damage. A number of earthquakes were experienced in parts of the Untied States, but only minor damage was reported. 

  15. Reconnaissance engineering geology of the Haines area, Alaska, with emphasis on evaluation of earthquake and other geologic hazards

    USGS Publications Warehouse

    Lemke, Richard Walter; Yehle, Lynn A.

    1972-01-01

    The Alaska earthquake of March 27, 1964, brought into sharp focus the need for engineering geologic studies in urban areas. Study of the Haines area constitutes an integral part of an overall program to evaluate earthquake and other geologic hazards in most of the larger Alaska coastal communities. The evaluations of geologic hazards that follow, although based only upon reconnaissance studies and, therefore, subject to revision, will provide broad guidelines useful in city and land-use planning. It is hoped that the knowledge gained will result in new facilities being built in the best possible geologic environments and being designed so as to minimize future loss of life and property damage. Haines, which is in the northern part of southeastern Alaska approximately 75 miles northwest of Juneau, had a population, of about 700 people in 1970. It is built at the northern end of the Chilkat Peninsula and lies within the Coast Mountains of the Pacific Mountain system. The climate is predominantly marine and is characterized by mild winters and cool summers. The mapped area described in this report comprises about 17 square miles of land; deep fiords constitute most of the remaining mapped area that is evaluated in this study. The Haines area was covered by glacier ice at least once and probably several times during the Pleistocene Epoch. The presence of emergent marine deposits, several hundred feet above sea level, demonstrates that the land has been uplifted relative to sea level since the last major deglaciation of the region about 10,000 years ago. The rate of relative uplift of the land at Haines during the past 39 years is 2.26 cm per year. Most or all of this uplift appears to be due to rebound as a result of deglaciation. Both bedrock and surficial deposits are present in the area. Metamorphic and igneous rocks constitute the exposed bedrock. The metamorphic rocks consist of metabasalt of Mesozoic age and pyroxenite of probable early middle Cretaceous age. The

  16. The bamA gene for anaerobic ring fission is widely distributed in the environment

    PubMed Central

    Porter, Abigail W.; Young, Lily Y.

    2013-01-01

    Benzoyl-CoA is the signature central metabolite associated with the anaerobic metabolism of a diverse range of compounds such as humic acid, lignin, amino acids, and industrial chemicals. Aromatic chemicals with different upstream degradation pathways all funnel into the downstream benzoyl-CoA pathway. Different genes encoding enzymes of the benzoyl-CoA pathway could be used as biomarkers for the anaerobic benzoyl-CoA pathway, however, the ring opening hydrolase, encoded by the bamA gene, is ideal because it is detected under a range of respiratory conditions, including under denitrifying, iron-reducing, sulfate-reducing, and fermentative conditions. This work evaluated DNA samples from six diverse environments for the presence of the bamA gene, and had positive results for every sample. Individual bamA gene clones from these sites were compared to published genome sequences. The clone sequences were distributed amongst the genome sequences, although there were clone sequences from two of the analyzed sites that formed a unique clade. Clone sequences were then grouped by site and analyzed with a functional operational taxonomic unit based clustering program to compare the bamA gene diversity of these sites to that of several locations reported in the literature. The results showed that the sequence diversity of the sites separated into two clusters, but there was no clear trend that could be related to the site characteristics. Interestingly, two pristine freshwater sites formed a subgroup within one of the larger clusters. Thus far the bamA gene has only been examined within the context of contaminated environments, however, this study demonstrates that the bamA gene is also detected in uncontaminated sites. The widespread presence of the bamA gene in diverse environments suggests that the anaerobic benzoyl-CoA pathway plays an important role in the global carbon cycle that has thus far been understudied. PMID:24133487

  17. Distribution of similar earthquakes in aftershocks of inland earthquakes

    NASA Astrophysics Data System (ADS)

    Hayashi, M.; Hiramatsu, Y.; Aftershock Observations Of 2007 Noto Hanto, G.

    2010-12-01

    Frictional properties control the slip behavior on a fault surface such as seismic slip and aseismic slip. Asperity, as a seismic slip area, is characterized by a strong coupling in the interseismic period and large coseismic slip. On the other hand, steady slip or afterslip occurs in an aseismic slip area around the asperity. If an afterslip area includes small asperities, a repeating rupture of single asperity can generate similar earthquakes due to the stress accumulation caused by the afterslip. We here investigate a detail distribution of similar earthquakes in the aftershocks of the 2007 Noto Hanto earthquake (Mjma 6.9) and the 2000 Western Tottori earthquake (Mjma 7.3), inland large earthquakes in Japan. We use the data obtained by the group for the aftershock observations of the 2007 Noto Hanto Earthquake and by the group for the aftershock observations of the 2000 Western Tottori earthquake. First, we select pairs of aftershocks whose cross correlation coefficients in 10 s time window of band-pass filtered waveforms of 1~4 Hz are greater than 0.95 at more than 5 stations and divide those into groups by a link of the cross correlation coefficients. Second, we reexamine the arrival times of P and S waves and the maximum amplitude for earthquakes of each group and apply the double-difference method (Waldhouser and Ellsworth, 2000) to relocate them. As a result of the analysis, we find 24 groups of similar earthquakes in the aftershocks on the source fault of the 2007 Noto Hanto Earthquake and 86 groups of similar earthquakes in the aftershocks on the source fault of the 2000 Western Tottori Earthquake. Most of them are distributed around or outside the asperity of the main shock. Geodetic studies reported that postseismic deformation was detected for the both earthquakes (Sagiya et al., 2002; Hashimoto et al., 2008). The source area of similar earthquakes seems to correspond to the afterslip area. These features suggest that the similar earthquakes observed

  18. Scaling characteristics of ULF geomagnetic fields at the Guam seismoactive area and their dynamics in relation to the earthquake

    NASA Astrophysics Data System (ADS)

    Smirnova, N.; Hayakawa, M.; Gotoh, K.; Volobuev, D.

    The long-term evolution of scaling (fractal) characteristics of the ULF geomagnetic fields in the seismoactive region of the Guam Island is studied in relation to the strong (Ms = 8.0) nearby earthquake of 8 August 1993. The selected period covers 10 months before and 10 months after the earthquake. The FFT procedure, Burlaga-Klein approach and Higuchi method, have been applied to calculate the scaling exponents and fractal dimensions of the ULF time series. It is found that the spectrum of ULF emissions exhibits, on average, a power law behaviour S(f ) α f -b , which is a fingerprint of the typical fractal (self-affine) time series. The spectrum slope b fluctuates quasi-periodically during the course of time in a range of b = 2.5-0.7, which corresponds to the fractional Brownian motion with both persistent and antipersistent behaviour. An tendency is also found for the spectrum slope to decrease gradually when approaching the earthquake date. Such a tendency manifests itself at all local times, showing a gradual evolution of the structure of the ULF noise to a typical flicker noise structure in proximity to the large earthquake event. We suggest considering such a peculiarity as an earthquake precursory signature. One more effect related to the earthquake is revealed: the longest quasi-period, which is 27 days, disappeared from the variations of the ULF emission spectrum slope during the earthquake, and it reappeared three months after the event. Physical interpretation of the peculiarities revealed has been done on the basis of the SOC (self-organized criticality) concept.

  19. Analysis of the impact of fault mechanism radiation patterns on macroseismic fields in the epicentral area of 1998 and 2004 Krn Mountains earthquakes (NW Slovenia).

    PubMed

    Gosar, Andrej

    2014-01-01

    Two moderate magnitude (Mw = 5.6 and 5.2) earthquakes in Krn Mountains occurred in 1998 and 2004 which had maximum intensity VII-VIII and VI-VII EMS-98, respectively. Comparison of both macroseismic fields showed unexpected differences in the epicentral area which cannot be explained by site effects. Considerably, different distribution of the highest intensities can be noticed with respect to the strike of the seismogenic fault and in some localities even higher intensities have been estimated for the smaller earthquake. Although hypocentres of both earthquakes were only 2 km apart and were located on the same seismogenic Ravne fault, their focal mechanisms showed a slight difference: almost pure dextral strike-slip for the first event and a strike-slip with small reverse component on a steep fault plane for the second one. Seismotectonically the difference is explained as an active growth of the Ravne fault at its NW end. The radiation patterns of both events were studied to explain their possible impact on the observed variations in macroseismic fields and damage distribution. Radiation amplitude lobes were computed for three orthogonal directions: radial P, SV, and SH. The highest intensities of both earthquakes were systematically observed in directions of four (1998) or two (2004) large amplitude lobes in SH component (which corresponds mainly to Love waves), which have significantly different orientation for both events. On the other hand, radial P direction, which is almost purely symmetrical for the strike-slip mechanism of 1998 event, showed for the 2004 event that its small reverse component of movement has resulted in a very pronounced amplitude lobe in SW direction where two settlements are located which expressed higher intensities in the case of the 2004 event with respect to the 1998 one. Although both macroseismic fields are very complex due to influences of multiple earthquakes, retrofitting activity after 1998, site effects, and sparse

  20. Physical activity and sedentary behavior among children and adolescents living in an area affected by the 2011 Great East Japan earthquake and tsunami for 3 years

    PubMed Central

    Okazaki, Kanzo; Suzuki, Koya; Sakamoto, Yuzuru; Sasaki, Keiji

    2015-01-01

    The purpose of this study is to examine the change in physical activity levels among children and adolescents living in the area affected by the 2011 earthquake and tsunami for 3 years immediately following the disaster. Children and adolescents graded four to nine and attending school in the Pacific coastal area of northern Japan were included in a total of four serial prevalence investigations: the first at 6 months after the earthquake/tsunami (I, n = 434) and additional surveys at 1 year (II, n = 437), 2 years (III, n = 401), and 3 years (IV, n = 365) after the earthquake. Students were also required to undergo assessment of their accelerometer-determined daily steps and sedentary time using a self-administrated questionnaire. Accelerometer-determined median daily steps of children and adolescents were significantly different (p < 0.05) on both weekdays and weekends over 3 years. The median daily steps of children of both genders on weekdays and those of girls on weekends at period IV were significantly lower than those at period I. In addition, the median daily steps of adolescents on weekdays among girls and weekends among boys at period IV were significantly lower than those at period I. It appears that children and adolescents who survive the earthquake and tsunami experience a decrease in physical activity levels. Future research should elucidate longitudinal demographic and sociocultural factors that contribute to changes in physical activity levels among children and adolescents living in the areas affected by these disasters. PMID:26844143

  1. Aminobacter MSH1-Mineralisation of BAM in Sand-Filters Depends on Biological Diversity

    PubMed Central

    Ekelund, Flemming; Harder, Christoffer Bugge; Knudsen, Berith Elkær; Aamand, Jens

    2015-01-01

    BAM (2,6-dichlorobenzamide) is a metabolite of the pesticide dichlobenil. Naturally occurring bacteria that can utilize BAM are rare. Often the compound cannot be degraded before it reaches the groundwater and therefore it poses a serious threat to drinking water supplies. The bacterial strain Aminobacter MSH1 is a BAM degrader and therefore a potential candidate to be amended to sand filters in waterworks to remediate BAM polluted drinking water. A common problem in bioremediation is that bacteria artificially introduced into new diverse environments often thrive poorly, which is even more unfortunate because biologically diverse environments may ensure a more complete decomposition. To test the bioaugmentative potential of MSH1, we used a serial dilution approach to construct microcosms with different biological diversity. Subsequently, we amended Aminobacter MSH1 to the microcosms in two final concentrations; i.e. 105 cells mL-1 and 107 cells mL-1. We anticipated that BAM degradation would be most efficient at “intermediate diversities” as low diversity would counteract decomposition because of incomplete decomposition of metabolites and high diversity would be detrimental because of eradication of Aminobacter MSH1. This hypothesis was only confirmed when Aminobacter MSH1 was amended in concentrations of 105 cells mL-1.Our findings suggest that Aminobacter MSH1 is a very promising bioremediator at several diversity levels. PMID:26076202

  2. A seismological study of shallow weak earthquakes in the urban area of Hamburg city, Germany, and its possible relation to salt dissolution

    NASA Astrophysics Data System (ADS)

    Dahm, Torsten; Heimann, Sebastian; Bialowons, Wilhelm

    2010-05-01

    In the night from 8/9 April 2009, shortly after midnight on Maundy Thursday before Easter, several people in Gross-Flottbek, Hamburg, felt unusual strong ground shocks so that some of them left their houses in fear of earthquake shaking. Police and Fire Brigade received phone calls of worried residents, and few days later Internet pages were published where people reported their observations. On 21 April 2009 at about 8 p.m. local time a second micro-earthquake was felt. Damage to buildings or infrastructure did not occur to our knowledge. The Institute of Geophysics, University of Hamburg, installed from 22 April to 17 May 2009 three temporal seismic stations in the epicentral area. Seismological data from two close-by stations at the Deutsches Elektron-Synchrotron (DESY) in about 1 km and the Geophysical Institute in about 7 km distance were collected and integrated to the temporal network. The events occurred above the roof of the shallow Othmarschen Langenfelde salt diapir (OLD), in an area known for active sinkhole formation and previous historic ground shaking events. The analysis of the seismological data recovers that three shallow micro-earthquakes occurred from 8 to 21 April at a depth of about 100m, the largest one with a moment magnitude of about MW 0.6. Depth location of such shallow events is difficult with standard methods, and is here constrained by waveform modeling of surface waves. Earthquakes occurring in soft sediments within the uppermost 100 m are a rare phenomena and cannot be explained by standard models. Rupture process in soft sediments differ from those on faults in more competent rock. We discuss the rupture and source mechanism of the earthquakes in the context of previous historic shocks and existing sinkhole and deformation data. Although the event was so weak, the rupture duration was unusual long and possibly 0.3 s. Three possible models for the generation of repeated micro-earthquakes in Gross Flottbek are developed and discussed

  3. Millennial coastal uplift rates and the seismic cycle in the 2011 Mw 9.0 Tohoku-oki earthquake area, Japan

    NASA Astrophysics Data System (ADS)

    Mechernich, Silke; Meghraoui, Mustapha; Cetin, Esra; Toda, Shinji; Okumura, Koji

    2013-04-01

    The Mw 9.0 Tohoku-oki earthquake and the record of major historical seismic events including the AD 869 Jogan earthquake on the Japan trench illustrate the active tectonic capability on the subduction zone. The recent coastal deformation is revealed by the 2011 coseismic subsidence (up to 1.2 m) and postseismic uplift (up to 20 cm within 1.5 years) obtained from leveling and GPS measurements. 100 years before the earthquake, subsidence at a rate of ~1 mm/a was documented. The correlation between these short-term geodetic results and long-term geologic data is decisive for understanding of the tectonic process and the related earthquake cycle on the subducting Pacific slab. Thus, we study the millennial vertical deformation along the coastline of northern Honshu Island (38.2°N to 41.2°N) in the frame of the PALET project (ANR-JST Flash program). The exposure of emerged marine terraces, wave-cut platforms and notches allow us to determine the deformation rate during the Late Pleistocene and Holocene. Coastline terraces of marine isotope stages MIS5e (124 ka) to MIS19 (~780 ka) indicate uplift rates of 0.2-0.4 mm/a and 0.1-0.2 mm/a in the northern and southern study area, respectively. Numerous younger notches and wave-cut platforms are identified at several height levels between 1 and 10 m above sea level. Two radiocarbon samples of wood remnants yielded an age of ~2.8 cal ka BP for a 3.2 m high terrace in the north (40.7°N), and a shell fragments on a notch in resistant conglomerates (39.7°N) revealed an age of 47.1 ± 2.2 cal ka BP. After correction for sea level change, both data points yield uplift rates of ~1 mm/a, which denotes clear acceleration in uplift during the Late Quaternary. An elastic dislocation model of the co-, post- and interseismic slip distribution shows how the successive coastal subsidence during M9-class earthquakes is concealed by the long-term uplift due to deep creeping deformation. The distribution of lower uplift rates in the

  4. 3D P-wave velocity structure of the crust and relocation of earthquakes in the Lushan, China, source area

    NASA Astrophysics Data System (ADS)

    Yu, Xiangwei; Wang, Xiaona; Zhang, Wenbo

    2016-04-01

    Many researchers have investigated the Lushan source area with geological and geophysical approaches since the 2013 Lushan, China, earthquake happened. Compared with the previous tomographic studies, we have used a much large data set and an updated tomographic method to determine a small scale three-dimensional P wave velocity structure with spatial resolution less than 5km, which plays the important role for understanding the deep structure and the genetic mechanism beneath the Lushan area. The double difference seismic tomography method is applied to 50,711 absolute first arrival P wave arrival times and 7,294,691 high quality relative P arrival times of 5,285 events of Lushan seismic sequence to simultaneously determine the detailed crustal 3D P wave velocity structure and the hypocenter parameters in the Lushan seismic area. This method takes account of the path anomaly biases explicitly by making full use of valuable information of seismic wave propagation jointly with absolute and relative arrival time data. Our results show that the Lushan mainshock locates at 30.28N, 103.98E, with the depth of 16.38km. The front edge of aftershock in the northeast of mainshock present a spade with a steep dip angle, the aftershocks' extended length is about 12km. In the southwest of Lushan mainshock, the front edge of aftershock in low velocity zone slope gently, the aftershocks' extended length is about 23km. Our high-resolution tomographic model not only displays the general features contained in the previous models, but also reveals some new features. The Tianquan, Shuangshi and Daguan line lies in the transition zone between high velocity anomalies to the southeast and low velocity anomalies to the northwest at the ground surface. An obvious high-velocity anomaly is visible in Daxing area. With the depth increasing, Baoxing high velocity anomaly extends to Lingguan, while the southeast of the Tianquan, Shuangshi and Daguan line still shows low velocity. The high

  5. Surface Fractures Formed in the Potrero Canyon, Tapo Canyon, and McBean Parkway Areas in Association with the 1994 Northridge, California Earthquake

    USGS Publications Warehouse

    Rymer, Michael J.; Treiman, Jerome A.; Powers, Thomas J.; Fumal, Thomas E.; Schwartz, David P.; Hamilton, John C.; Cinti, Francesca R.

    2001-01-01

    INTRODUCTION The magnitude 6.7 (M6.7) Northridge earthquake of 17 January 1994 strongly shook the Los Angeles urban region, resulting in 33 direct deaths, more than 20,000 people forced out of their homes, and an estimated $20 billion in damage (Hall, 1994). The earthquake was caused by slip on a previously unrecognized south-dipping fault buried beneath the San Fernando Valley. Slip on the fault propagated from a depth of about 19 km to about 8 km below the ground surface (USGS and SCEC, 1994). Although there was no surface faulting associated with the causative fault, surface fractures did develop along at least one fault (Mission Wells fault) and also in areas without recognized faults (Hart and others, 1995; Hecker and others, 1995a, 1995b; Rymer and others, 1995; Treiman, 1995). The term 'surface fractures' is used herein to describe ground breakage that is not associated with primary faulting or with triggered, secondary, surface faulting on a deep seismogenic fault. This report describes fault- and nonfault-related surface fractures that occurred at three sites, Potrero Canyon, Tapo Canyon, and the McBean Parkway area, 22 to 28 km north-northwest of the main shock (Fig. 1). Investigation of these sites documents far reaching effects of even moderately large earthquakes. Study of such effects has become increasingly important with further urbanization and development. Hecker and others (1995a, 1995b) documented the distribution of surface deformation associated with the Northridge earthquake in the Granada Hills area. The search for surface faulting and surface fracturing was initiated within hours of the earthquake. Both ground and airborne searches were made of the region. After fresh surface fractures were found in Potrero Canyon, aerial photographs were taken of the area (including the McBean Parkway site) by I.K. Curtis, on 21 January 1994, at scales of about 1:2,000 and 1:6,000. These aerial photographs were studied under high magnification to

  6. BAMS2 Workspace: a comprehensive and versatile neuroinformatic platform for collating and processing neuroanatomical connections

    PubMed Central

    Bota, Mihail; Talpalaru, Ştefan; Hintiryan, Houri; Dong, Hong-Wei; Swanson, Larry W.

    2014-01-01

    We present in this paper a novel neuroinformatic platform, the BAMS2 Workspace (http://brancusi1.usc.edu), designed for storing and processing information about gray matter region axonal connections. This de novo constructed module allows registered users to directly collate their data by using a simple and versatile visual interface. It also allows construction and analysis of sets of connections associated with gray matter region nomenclatures from any designated species. The Workspace includes a set of tools allowing the display of data in matrix and networks formats, and the uploading of processed information in visual, PDF, CSV, and Excel formats. Finally, the Workspace can be accessed anonymously by third party systems to create individualized connectivity networks. All features of the BAMS2 Workspace are described in detail, and are demonstrated with connectivity reports collated in BAMS and associated with the rat sensory-motor cortex, medial frontal cortex, and amygdalar regions. PMID:24668342

  7. The Basic Angle Monitoring (BAM) software tool in the context of Gaia's astrometric verification

    NASA Astrophysics Data System (ADS)

    Riva, Alberto; Lattanzi, Mario G.; Drimmel, Ronald; Gai, Mario; Busonero, Deborah; Buzzi, Raffaella; Pecoraro, Marco; Russo, Federico; Messineo, Rosario

    2014-08-01

    The goal of the Gaia mission is to achieve micro-arcsecond astrometry, making Gaia the most important astro- metric space mission of the 21st century. To achieve this performance several innovative technological solutions have been realized as part of the satellite's scientific payload. A critical component of the Gaia scientific pay- load is the Basic Angle Monitoring device (BAM), an interferometric metrology instrument with the task of monitoring, to some picometers, the variation of the Basic Angle between Gaia's two telescopes. In this paper we provide an overview of the AVU/BAM software, running at the Italian Data Processing Center (DPCT), to analyze the BAM data and to recover the basic angle variations at the micro-arcosecond level. Outputs based on preliminary data from Gaia's Commissioning phase are shown as an example.

  8. BAMS2 workspace: a comprehensive and versatile neuroinformatic platform for collating and processing neuroanatomical connections.

    PubMed

    Bota, Mihail; Talpalaru, Stefan; Hintiryan, Houri; Dong, Hong-Wei; Swanson, Larry W

    2014-10-01

    We describe a novel neuroinformatic platform, the BAMS2 Workspace (http://brancusi1.usc.edu), designed for storing and processing information on gray matter region axonal connections. This de novo constructed module allows registered users to collate their data directly by using a simple and versatile visual interface. It also allows construction and analysis of sets of connections associated with gray matter region nomenclatures from any designated species. The Workspace includes a set of tools allowing the display of data in matrix and networks formats and the uploading of processed information in visual, PDF, CSV, and Excel formats. Finally, the Workspace can be accessed anonymously by third-party systems to create individualized connectivity networks. All features of the BAMS2 Workspace are described in detail and are demonstrated with connectivity reports collated in BAMS and associated with the rat sensory-motor cortex, medial frontal cortex, and amygdalar regions. PMID:24668342

  9. Fungal hyphae stimulate bacterial degradation of 2,6-dichlorobenzamide (BAM).

    PubMed

    Knudsen, Berith Elkær; Ellegaard-Jensen, Lea; Albers, Christian Nyrop; Rosendahl, Søren; Aamand, Jens

    2013-10-01

    Introduction of specific degrading microorganisms into polluted soil or aquifers is a promising remediation technology provided that the organisms survive and spread in the environment. We suggest that consortia, rather than single strains, may be better suited to overcome these challenges. Here we introduced a fungal-bacterial consortium consisting of Mortierella sp. LEJ702 and the 2,6-dichlorobenzamide (BAM)-degrading Aminobacter sp. MSH1 into small sand columns. A more rapid mineralisation of BAM was obtained by the consortium compared to MSH1 alone especially at lower moisture contents. Results from quantitative real-time polymerase chain reaction (qPCR) demonstrated better spreading of Aminobacter when Mortierella was present suggesting that fungal hyphae may stimulate bacterial dispersal. Extraction and analysis of BAM indicated that translocation of the compound was also affected by the fungal hyphae in the sand. This suggests that fungal-bacterial consortia are promising for successful bioremediation of pesticide contamination.

  10. Earthquake history of Mississippi

    USGS Publications Warehouse

    von Hake, C. A.

    1974-01-01

    Since its admission into the Union in 1817, Mississippi has had only four earthquakes of intensity V or greater within its borders. Although the number of earthquakes known to have been centered within Mississippi's boundaries is small, the State has been affected by numerous shocks located in neighboring States. In 1811 and 1812, a series of great earthquakes near the New Madrid Missouri area was felt in Mississippi as far south as the gulf coast. The New Madrid series caused the banks of the Mississippi River to cave in as far as Vicksburg, mroe than 300 miles from the epicentral region. As a result of this great earthquake series, the northwest corner of Mississippi is in seismic risk zone 3, the highest risk zone. Expect for the new Madrid series, effects in Mississippi from earthquakes located outside of the State have been less than intensity V. 

  11. Identification of the Amidase BbdA That Initiates Biodegradation of the Groundwater Micropollutant 2,6-dichlorobenzamide (BAM) in Aminobacter sp. MSH1.

    PubMed

    T'Syen, Jeroen; Tassoni, Raffaella; Hansen, Lars; Sorensen, Søren J; Leroy, Baptiste; Sekhar, Aswini; Wattiez, Ruddy; De Mot, René; Springael, Dirk

    2015-10-01

    2,6-dichlorobenzamide (BAM) is a recalcitrant groundwater micropollutant that poses a major problem for drinking water production in European countries. Aminobacter sp. MSH1 and related strains have the unique ability to mineralize BAM at micropollutant concentrations but no information exists on the genetics of BAM biodegradation. An amidase-BbdA-converting BAM to 2,6-dichlorobenzoic acid (DCBA) was purified from Aminobacter sp. MSH1. Heterologous expression of the corresponding bbdA gene and its absence in MSH1 mutants defective in BAM degradation, confirmed its BAM degrading function. BbdA shows low amino acid sequence identity with reported amidases and is encoded by an IncP1-β plasmid (pBAM1, 40.6 kb) that lacks several genes for conjugation. BbdA has a remarkably low KM for BAM (0.71 μM) and also shows activity against benzamide and ortho-chlorobenzamide (OBAM). Differential proteomics and transcriptional reporter analysis suggest the constitutive expression of bbdA in MSH1. Also in other BAM mineralizing Aminobacter sp. strains, bbdA and pBAM1 appear to be involved in BAM degradation. BbdA's high affinity for BAM and its constitutive expression are of interest for using strain MSH1 in treatment of groundwater containing micropollutant concentrations of BAM for drinking water production.

  12. Activation of the Escherichia coli β-barrel assembly machine (Bam) is required for essential components to interact properly with substrate.

    PubMed

    Ricci, Dante P; Hagan, Christine L; Kahne, Daniel; Silhavy, Thomas J

    2012-02-28

    The outer membrane (OM) of gram-negative bacteria such as Escherichia coli contains lipoproteins and integral β-barrel proteins (outer-membrane proteins, OMPs) assembled into an asymmetrical lipid bilayer. Insertion of β-barrel proteins into the OM is mediated by a protein complex that contains the OMP BamA and four associated lipoproteins (BamBCDE). The mechanism by which the Bam complex catalyzes the assembly of OMPs is not known. We report here the isolation and characterization of a temperature-sensitive lethal mutation, bamAE373K, which alters the fifth polypeptide transport-associated domain and disrupts the interaction between the BamAB and BamCDE subcomplexes. Suppressor mutations that map to codon 197 in bamD restore Bam complex function to wild-type levels. However, these suppressors do not restore the interaction between BamA and BamD; rather, they bypass the requirement for stable holocomplex formation by activating BamD. These results imply that BamA and BamD interact directly with OMP substrates.

  13. Defeating Earthquakes

    NASA Astrophysics Data System (ADS)

    Stein, R. S.

    2012-12-01

    our actions. Using these global datasets will help to make the model as uniform as possible. The model must be built by scientists in the affected countries with GEM's support, augmented by their insights and data. The model will launch in 2014; to succeed it must be open, international, independent, and continuously tested. But the mission of GEM is not just the likelihood of ground shaking, but also gaging the economic and social consequences of earthquakes, which greatly amplify the losses. For example, should the municipality of Istanbul retrofit schools, or increase its insurance reserves and recovery capacity? Should a homeowner in a high-risk area move or strengthen her building? This is why GEM is a public-private partnership. GEM's fourteen public sponsors and eight non-governmental organization members are standing for the developing world. To extend GEM into the financial world, we draw upon the expertise of companies. GEM's ten private sponsors have endorsed the acquisition of public knowledge over private gain. In a competitive world, this is a courageous act. GEM is but one link in a chain of preparedness: from earth science and engineering research, through groups like GEM, to mitigation, retrofit or relocate decisions, building codes and insurance, and finally to prepared hospitals, schools, and homes. But it is a link that our community can make strong.

  14. Earthquakes; March-April 1975

    USGS Publications Warehouse

    Person, W.J.

    1975-01-01

    There were no major earthquakes (magnitude 7.0-7.9) in March or April; however, there were earthquake fatalities in Chile, Iran, and Venezuela and approximately 35 earthquake-related injuries were reported around the world. In the United States a magnitude 6.0 earthquake struck the Idaho-Utah border region. Damage was estimated at about a million dollars. The shock was felt over a wide area and was the largest to hit the continental Untied States since the San Fernando earthquake of February 1971. 

  15. Passivity of memristor-based BAM neural networks with different memductance and uncertain delays.

    PubMed

    Anbuvithya, R; Mathiyalagan, K; Sakthivel, R; Prakash, P

    2016-08-01

    This paper addresses the passivity problem for a class of memristor-based bidirectional associate memory (BAM) neural networks with uncertain time-varying delays. In particular, the proposed memristive BAM neural networks is formulated with two different types of memductance functions. By constructing proper Lyapunov-Krasovskii functional and using differential inclusions theory, a new set of sufficient condition is obtained in terms of linear matrix inequalities which guarantee the passivity criteria for the considered neural networks. Finally, two numerical examples are given to illustrate the effectiveness of the proposed theoretical results.

  16. New robust passivity criteria for stochastic fuzzy BAM neural networks with time-varying delays

    NASA Astrophysics Data System (ADS)

    Mathiyalagan, Kalidass; Sakthivel, Rathinasamy; Marshal Anthoni, Selvaraj

    2012-03-01

    In this paper, we consider the problem of passivity analysis issue for a class of stochastic fuzzy BAM neural networks with time varying delays. By employing the idea of delay-fractioning technique and Lyapunov stability theory, a new set of sufficient conditions are derived in terms of linear matrix inequalities for obtaining the passivity condition of the considered neural network model. First, we derive the passivity condition for stochastic fuzzy BAM neural networks with time varying delays and then the result is extended to the case with uncertainties. Two numerical examples are given to illustrate the effectiveness and conservatism of the obtained results.

  17. Seismic imaging beneath an InSAR anomaly in eastern Washington State: Shallow faulting associated with an earthquake swarm in a low-hazard area

    USGS Publications Warehouse

    Stephenson, William J.; Odum, Jackson K.; Wicks, Chuck; Pratt, Thomas L.; Blakely, Richard J.

    2016-01-01

    In 2001, a rare swarm of small, shallow earthquakes beneath the city of Spokane, Washington, caused ground shaking as well as audible booms over a five‐month period. Subsequent Interferometric Synthetic Aperture Radar (InSAR) data analysis revealed an area of surface uplift in the vicinity of the earthquake swarm. To investigate the potential faults that may have caused both the earthquakes and the topographic uplift, we collected ∼3  km of high‐resolution seismic‐reflection profiles to image the upper‐source region of the swarm. The two profiles reveal a complex deformational pattern within Quaternary alluvial, fluvial, and flood deposits, underlain by Tertiary basalts and basin sediments. At least 100 m of arching on a basalt surface in the upper 500 m is interpreted from both the seismic profiles and magnetic modeling. Two west‐dipping faults deform Quaternary sediments and project to the surface near the location of the Spokane fault defined from modeling of the InSAR data.

  18. Using 2,6-dichlorobenzamide (BAM) degrading Aminobacter sp. MSH1 in flow through biofilters--initial adhesion and BAM degradation potentials.

    PubMed

    Albers, Christian Nyrop; Jacobsen, Ole Stig; Aamand, Jens

    2014-01-01

    Micropollutants in groundwater are given significant attention by water companies and authorities due to an increasing awareness that they might be present even above the legal threshold values. As part of our investigations of the possibility to remove the common groundwater pollutant 2,6-dichlorobenzamide (BAM) by introducing the efficient BAM degrader Aminobacter sp. MSH1 into biologically active sand filters, we investigated if the strain adheres to filters containing various filter materials and if the initial adherence and subsequent degradation of BAM could be optimized. We found that most of the inoculated MSH1 cells adhered fast and that parameters like pH and ionic strength had only a minor influence on the adhesion despite huge influence on cell surface hydrophobicity. At the given growth protocol, the MSH1 strain apparently developed a subpopulation that had lost its ability to adhere to the filter materials, which was supported by attempted reinoculation of non-adhered cells. Analysis by quantitative PCR showed that most cells adhered in the top of the filters and that some of these were lost from the filters during initial operation, while insignificant losses occurred after 1 day of operation. The inoculated filters were found to degrade 2.7 μg/L BAM to below 0.1 μg/L at a 1.1-h residence time with insignificant formation of known degradation products. In conclusion, most filter materials and water types should be feasible for inoculation with the MSH1 strain, while more research into degradation at low concentrations and temperatures is needed before this technology is ready for use at actual waterworks. PMID:23670436

  19. Using 2,6-dichlorobenzamide (BAM) degrading Aminobacter sp. MSH1 in flow through biofilters--initial adhesion and BAM degradation potentials.

    PubMed

    Albers, Christian Nyrop; Jacobsen, Ole Stig; Aamand, Jens

    2014-01-01

    Micropollutants in groundwater are given significant attention by water companies and authorities due to an increasing awareness that they might be present even above the legal threshold values. As part of our investigations of the possibility to remove the common groundwater pollutant 2,6-dichlorobenzamide (BAM) by introducing the efficient BAM degrader Aminobacter sp. MSH1 into biologically active sand filters, we investigated if the strain adheres to filters containing various filter materials and if the initial adherence and subsequent degradation of BAM could be optimized. We found that most of the inoculated MSH1 cells adhered fast and that parameters like pH and ionic strength had only a minor influence on the adhesion despite huge influence on cell surface hydrophobicity. At the given growth protocol, the MSH1 strain apparently developed a subpopulation that had lost its ability to adhere to the filter materials, which was supported by attempted reinoculation of non-adhered cells. Analysis by quantitative PCR showed that most cells adhered in the top of the filters and that some of these were lost from the filters during initial operation, while insignificant losses occurred after 1 day of operation. The inoculated filters were found to degrade 2.7 μg/L BAM to below 0.1 μg/L at a 1.1-h residence time with insignificant formation of known degradation products. In conclusion, most filter materials and water types should be feasible for inoculation with the MSH1 strain, while more research into degradation at low concentrations and temperatures is needed before this technology is ready for use at actual waterworks.

  20. 3D seismic velocity structure in the rupture area of the 2014 M8.2 Iquique earthquake in Northern Chile

    NASA Astrophysics Data System (ADS)

    Woollam, Jack; Fuenzallida, Amaya; Garth, Tom; Rietbrock, Andreas; Ruiz, Sergio; Tavera, Hernando

    2016-04-01

    Seismic velocity tomography is one of the key tools in Earth sciences to image the physical properties of the subsurface. In recent years significant advances have been made to image the Chilean subductions zone, especially in the area of the 2010 M8.8 Maule earthquake (e.g. Hicks et al., 2014), providing much needed physical constraints for earthquakes source inversions and rupture models. In 2014 the M8.2 Iquique earthquake struck the northern part of the Chilean subduction zone in close proximity to the Peruvian boarder. The pre- and aftershock sequence of this major earthquake was recorded by a densified seismological network in Northern Chile and Southern Peru, which provides an excellent data set to study in depth the 3D velocity structure along the subduction megathrust. Based on an automatic event catalogue of nearly 10,000 events spanning the time period March to May 2014 we selected approximately 450 events for a staggered 3D inversion approach. Events are selected to guarantee an even ray coverage through the inversion volume. We only select events with a minimum GAP of 200 to improve depth estimates and therefore increase resolution in the marine forearc. Additionally, we investigate secondary arrivals between the P- and S-wave arrival to improve depth location. Up to now we have processed about 450 events, from which about 150 with at least 30 P- and S-wave observations have been selected for the subsequent 3D tomography. Overall the data quality is very high, which allows arrival time estimates better than 0.05s on average. We will show results from the 1D, 2D, and preliminary 3D inversions and discuss the results together with the obtained seismicity distribution.

  1. The 1868 Hayward Earthquake Alliance: A Case Study - Using an Earthquake Anniversary to Promote Earthquake Preparedness

    NASA Astrophysics Data System (ADS)

    Brocher, T. M.; Garcia, S.; Aagaard, B. T.; Boatwright, J. J.; Dawson, T.; Hellweg, M.; Knudsen, K. L.; Perkins, J.; Schwartz, D. P.; Stoffer, P. W.; Zoback, M.

    2008-12-01

    Last October 21st marked the 140th anniversary of the M6.8 1868 Hayward Earthquake, the last damaging earthquake on the southern Hayward Fault. This anniversary was used to help publicize the seismic hazards associated with the fault because: (1) the past five such earthquakes on the Hayward Fault occurred about 140 years apart on average, and (2) the Hayward-Rodgers Creek Fault system is the most likely (with a 31 percent probability) fault in the Bay Area to produce a M6.7 or greater earthquake in the next 30 years. To promote earthquake awareness and preparedness, over 140 public and private agencies and companies and many individual joined the public-private nonprofit 1868 Hayward Earthquake Alliance (1868alliance.org). The Alliance sponsored many activities including a public commemoration at Mission San Jose in Fremont, which survived the 1868 earthquake. This event was followed by an earthquake drill at Bay Area schools involving more than 70,000 students. The anniversary prompted the Silver Sentinel, an earthquake response exercise based on the scenario of an earthquake on the Hayward Fault conducted by Bay Area County Offices of Emergency Services. 60 other public and private agencies also participated in this exercise. The California Seismic Safety Commission and KPIX (CBS affiliate) produced professional videos designed forschool classrooms promoting Drop, Cover, and Hold On. Starting in October 2007, the Alliance and the U.S. Geological Survey held a sequence of press conferences to announce the release of new research on the Hayward Fault as well as new loss estimates for a Hayward Fault earthquake. These included: (1) a ShakeMap for the 1868 Hayward earthquake, (2) a report by the U. S. Bureau of Labor Statistics forecasting the number of employees, employers, and wages predicted to be within areas most strongly shaken by a Hayward Fault earthquake, (3) new estimates of the losses associated with a Hayward Fault earthquake, (4) new ground motion

  2. Stress-based aftershock forecasts made within 24 h postmain shock: Expected north San Francisco Bay area seismicity changes after the 2014 M = 6.0 West Napa earthquake

    NASA Astrophysics Data System (ADS)

    Parsons, Tom; Segou, Margaret; Sevilgen, Volkan; Milner, Kevin; Field, Edward; Toda, Shinji; Stein, Ross S.

    2014-12-01

    We calculate stress changes resulting from the M = 6.0 West Napa earthquake on north San Francisco Bay area faults. The earthquake ruptured within a series of long faults that pose significant hazard to the Bay area, and we are thus concerned with potential increases in the probability of a large earthquake through stress transfer. We conduct this exercise as a prospective test because the skill of stress-based aftershock forecasting methodology is inconclusive. We apply three methods: (1) generalized mapping of regional Coulomb stress change, (2) stress changes resolved on Uniform California Earthquake Rupture Forecast faults, and (3) a mapped rate/state aftershock forecast. All calculations were completed within 24 h after the main shock and were made without benefit of known aftershocks, which will be used to evaluative the prospective forecast. All methods suggest that we should expect heightened seismicity on parts of the southern Rodgers Creek, northern Hayward, and Green Valley faults.

  3. Stress-based aftershock forecasts made within 24h post mainshock: Expected north San Francisco Bay area seismicity changes after the 2014M=6.0 West Napa earthquake

    USGS Publications Warehouse

    Parsons, Thomas E.; Segou, Margaret; Sevilgen, Volkan; Milner, Kevin; Field, Ned; Toda, Shinji; Stein, Ross S.

    2014-01-01

    We calculate stress changes resulting from the M= 6.0 West Napa earthquake on north San Francisco Bay area faults. The earthquake ruptured within a series of long faults that pose significant hazard to the Bay area, and we are thus concerned with potential increases in the probability of a large earthquake through stress transfer. We conduct this exercise as a prospective test because the skill of stress-based aftershock forecasting methodology is inconclusive. We apply three methods: (1) generalized mapping of regional Coulomb stress change, (2) stress changes resolved on Uniform California Earthquake Rupture Forecast faults, and (3) a mapped rate/state aftershock forecast. All calculations were completed within 24 h after the main shock and were made without benefit of known aftershocks, which will be used to evaluative the prospective forecast. All methods suggest that we should expect heightened seismicity on parts of the southern Rodgers Creek, northern Hayward, and Green Valley faults.

  4. Landslides caused by earthquakes.

    USGS Publications Warehouse

    Keefer, D.K.

    1984-01-01

    Data from 40 historical world-wide earthquakes were studied to determine the characteristics, geologic environments, and hazards of landslides caused by seismic events. This sample was supplemented with intensity data from several hundred US earthquakes to study relations between landslide distribution and seismic parameters. Correlations between magnitude (M) and landslide distribution show that the maximum area likely to be affected by landslides in a seismic event increases from approximately 0 at M = 4.0 to 500 000 km2 at M = 9.2. Each type of earthquake-induced landslide occurs in a particular suite of geologic environments. -from Author

  5. Earthquake history of Tennessee

    USGS Publications Warehouse

    von Hake, C. A.

    1977-01-01

     The western part of the State was shaken strongly by the New Madrid, Mo., earthquakes of 1811-12 and by earthquakes in 1843 and 1895. The area has also experienced minor shocks. Additional activity has occurred in the eastern part of the State, near the North Carolina border. Forty shocks of intensity V (Modified Mercalli scale) or greater have been cataloged as occurring within the State. Many other earthquakes centered in bordering States have affected points in Tennessee. The following summary covers only hose shocks of intensity VI or greater. 

  6. Proceedings of Conference XVIII: a workshop on "Continuing actions to reduce losses from earthquakes in the Mississippi Valley area," 24-26 May, 1982, St. Louis, Missouri

    USGS Publications Warehouse

    Gori, Paula L.; Hays, Walter W.; Kitzmiller, Carla

    1983-01-01

    payoff and trre lowest cost and effort requirements. These action plans, which identify steps that can be undertaken immediately to reduce losses from earthquakes in each of the seven States in the Mississippi Valley area, are contained in this report. The draft 5-year plan for the Central United States, prepared in the Knoxville workshop, was the starting point of the small group discussions in the St. Louis workshop which lead to the action plans contained in this report. For completeness, the draft 5-year plan for the Central United States is reproduced as Appendix B.

  7. Lessons learned from the Great East Japan Earthquake: The need for disaster preparedness in the area of disaster mental health for children.

    PubMed

    Kozu, Shuei; Homma, Hiroaki

    2014-01-01

    The Great East Japan Earthquake on March 11, 2011 brought unprecedented challenges to individuals, families, and communities of the Tohoku region in Japan. Children are especially vulnerable to the postdisaster risk factors that impact their ability to heal. The destruction of the infrastructure by the disasters made it more challenging to reach out to children in an area where the stigma against mental illness is persistent. The authors share their experiences, what they heard from patients, and their reflections on lessons learned. The authors recommend the development of a coordinated mental health response system in preparation for the next disaster.

  8. WGCEP Historical California Earthquake Catalog

    USGS Publications Warehouse

    Felzer, Karen R.; Cao, Tianqing

    2008-01-01

    This appendix provides an earthquake catalog for California and the surrounding area. Our goal is to provide a listing for all known M > 5.5 earthquakes that occurred from 1850-1932 and all known M > 4.0 earthquakes that occurred from 1932-2006 within the region of 31.0 to 43.0 degrees North and -126.0 to -114.0 degrees West. Some pre-1932 earthquakes 4 5, before the Northern California network was online. Some earthquakes from 1900-1932, and particularly from 1910-1932 are also based on instrumental readings, but the quality of the instrumental record and the resulting analysis are much less precise than for later listings. A partial exception is for some of the largest earthquakes, such as the San Francisco earthquake of April 18, 1906, for which global teleseismic records (Wald et al. 1993) and geodetic measurements (Thatcher et al. 1906) have been used to help determine magnitudes.

  9. Episodic tremor triggers small earthquakes

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2011-08-01

    It has been suggested that episodic tremor and slip (ETS), the weak shaking not associated with measurable earthquakes, could trigger nearby earthquakes. However, this had not been confirmed until recently. Vidale et al. monitored seismicity in the 4-month period around a 16-day episode of episodic tremor and slip in March 2010 in the Cascadia region. They observed five small earthquakes within the subducting slab during the ETS episode. They found that the timing and locations of earthquakes near the tremor suggest that the tremor and earthquakes are related. Furthermore, they observed that the rate of earthquakes across the area was several times higher within 2 days of tremor activity than at other times, adding to evidence of a connection between tremor and earthquakes. (Geochemistry, Geophysics, Geosystems, doi:10.1029/2011GC003559, 2011)

  10. OMG Earthquake! Can Twitter improve earthquake response?

    NASA Astrophysics Data System (ADS)

    Earle, P. S.; Guy, M.; Ostrum, C.; Horvath, S.; Buckmaster, R. A.

    2009-12-01

    The U.S. Geological Survey (USGS) is investigating how the social networking site Twitter, a popular service for sending and receiving short, public, text messages, can augment its earthquake response products and the delivery of hazard information. The goal is to gather near real-time, earthquake-related messages (tweets) and provide geo-located earthquake detections and rough maps of the corresponding felt areas. Twitter and other social Internet technologies are providing the general public with anecdotal earthquake hazard information before scientific information has been published from authoritative sources. People local to an event often publish information within seconds via these technologies. In contrast, depending on the location of the earthquake, scientific alerts take between 2 to 20 minutes. Examining the tweets following the March 30, 2009, M4.3 Morgan Hill earthquake shows it is possible (in some cases) to rapidly detect and map the felt area of an earthquake using Twitter responses. Within a minute of the earthquake, the frequency of “earthquake” tweets rose above the background level of less than 1 per hour to about 150 per minute. Using the tweets submitted in the first minute, a rough map of the felt area can be obtained by plotting the tweet locations. Mapping the tweets from the first six minutes shows observations extending from Monterey to Sacramento, similar to the perceived shaking region mapped by the USGS “Did You Feel It” system. The tweets submitted after the earthquake also provided (very) short first-impression narratives from people who experienced the shaking. Accurately assessing the potential and robustness of a Twitter-based system is difficult because only tweets spanning the previous seven days can be searched, making a historical study impossible. We have, however, been archiving tweets for several months, and it is clear that significant limitations do exist. The main drawback is the lack of quantitative information

  11. [Effects of empathy on fund-raising activities on behalf of victims of the 2011 Great East Japan Earthquake, focusinig on the residents in the South Kanto area].

    PubMed

    Yamamoto, Youichi; Yoo, Seonyoung; Matsui, Yutaka

    2015-02-01

    Fund-raising activities on behalf of victims of the 2011 Great East Japan Earthquake during the year after the earthquake were investigated in residents of the South Kanto area (N = 749), which is adjacent to the disaster area. The percentage of people that raised funds was 67.4%. We investigated the effects of the following on fundraising activities: demographic variables (sex, age, and educational background), trait empathy (empathic concern, perspective taking, and personal distress), former experience with fund-raising activities, effects of similarity to victims (e.g., experienced inconveniences because of the disaster, or had problems returning home), and psychological closeness to victims (e.g, have family members or acquaintances that suffered from the disaster, or that once lived in the disaster area). The results indicated that fund-raising activities were affected by former experience with fund-raising, similarity to victims, psychological closeness to victims, empathic concern, and being female. The relationship between fund-raising activities for victims and empathy are discussed.

  12. Expression and functional analysis of Gm114, a putative mammalian ortholog of Drosophila bam

    PubMed Central

    Tang, Hao; Ross, Andrea; Capel, Blanche

    2008-01-01

    In the testis, the continuous production of sperm is maintained by a small population of stem cells called germ line stem cells (GSCs) in Drosophila, or spermatogonial stem cells (SSCs) in mammals. This stem cell population can self-renew or produce daughter cells that differentiate into mature sperm. In Drosophila, BMP signals inhibit GSC differentiation by blocking transcription of the gene, bag of marbles (bam). Once bam is activated, germ cells initiate differentiation. We identified a novel gene in mouse, Gm114, that shows homology to Drosophila bam. In male germ cells, expression of Gm114 begins at 12.5–13.5 days post coitum (dpc), the stage in mice when germ cells cease proliferation and begin differentiation into prospermatogonia. In adult testis, Gm114 is highly expressed in differentiated spermatocytes and spermatids but not in undifferentiated spermatogonia, strongly suggesting that, similar to Bam, GM114 plays an important role in mammalian germ line stem cell self-renewal and differentiation. Interestingly, deletion of the majority of the GM114 protein does not affect mouse viability or fertility. This suggests that either there is a function for the remaining N-terminal of GM114, or that there are alternative mechanisms in the mammalian system that control germ cell differentiation. PMID:18423593

  13. BioAssemblyModeler (BAM): User-Friendly Homology Modeling of Protein Homo- and Heterooligomers

    PubMed Central

    Xu, Qifang; Andrake, Mark; Dunbrack, Roland L.

    2014-01-01

    Many if not most proteins function in oligomeric assemblies of one or more protein sequences. The Protein Data Bank provides coordinates for biological assemblies for each entry, at least 60% of which are dimers or larger assemblies. BioAssemblyModeler (BAM) is a graphical user interface to the basic steps in homology modeling of protein homooligomers and heterooligomers from the biological assemblies provided in the PDB. BAM takes as input up to six different protein sequences and begins by assigning Pfam domains to the target sequences. The program utilizes a complete assignment of Pfam domains to sequences in the PDB, PDBfam (http://dunbrack2.fccc.edu/protcid/pdbfam), to obtain templates that contain any or all of the domains assigned to the target sequence(s). The contents of the biological assemblies of potential templates are provided, and alignments of the target sequences to the templates are produced with a profile-profile alignment algorithm. BAM provides for visual examination and mouse-editing of the alignments supported by target and template secondary structure information and a 3D viewer of the template biological assembly. Side-chain coordinates for a model of the biological assembly are built with the program SCWRL4. A built-in protocol navigation system guides the user through all stages of homology modeling from input sequences to a three-dimensional model of the target complex. Availability: http://dunbrack.fccc.edu/BAM. PMID:24922057

  14. Prototype Earthquake Early Warning System for Areas of Highest Seismic Risk in the Western U.S.

    NASA Astrophysics Data System (ADS)

    Bock, Y.; Geng, J.; Goldberg, D.; Saunders, J. K.; Haase, J. S.; Squibb, M. B.; Melgar, D.; Crowell, B. W.; Clayton, R. W.; Yu, E.; Walls, C. P.; Mann, D.; Mencin, D.; Mattioli, G. S.

    2015-12-01

    We report on a prototype earthquake early warning system for the Western U.S. based on GNSS (GPS+GLONASS) observations, and where available collocated GNSS and accelerometer data (seismogeodesy). We estimate with latency of 2-3 seconds GNSS displacement waveforms from more than 120 stations, focusing on the southern segment of the San Andreas fault, the Hayward and Rodgers Creek faults and Cascadia. The displacements are estimated using precise point positioning with ambiguity resolution (PPP-AR), which provides for efficient processing of hundreds of "clients" within the region of interest with respect to a reference frame well outside the expected zone of deformation. The GNSS displacements are useful for alleviating magnitude saturation concerns, rapid earthquake magnitude estimation using peak ground displacements, CMT solutions and finite fault slip models. However, GNSS alone is insufficient for strict earthquake early warning (i.e., P wave detection). Therefore, we employ a self-contained seismogeodetic technique, where collocations of GNSS and accelerometer instruments are available, to estimate real-time displacement and velocity waveforms using PPP-AR with accelerometers (PPP-ARA). Using the velocity waveforms we can detect the P wave arrival for earthquakes of interest (>M 5.5), estimate a hypocenter, S wave propagation, and earthquake magnitude using Pd scaling relationships within seconds. Currently we are gearing up to receive observatory-grade accelerometer data from the CISN. We have deployed 25 inexpensive MEMS accelerometers at existing GNSS stations. The SIO Geodetic Modules that control the flow of the GNSS and accelerometer data are being upgraded with in situ PPP-ARA and P wave picking. In situ processing allows us to use the data at the highest sampling rate of the GNSS receiver (10 Hz or higher), in combination with the 100 Hz accelerometer data. Adding the GLONASS data allows for increased precision in the vertical, an important factor in P

  15. Analysis of the impact of fault mechanism radiation patterns on macroseismic fields in the epicentral area of 1998 and 2004 Krn Mountains earthquakes (NW Slovenia).

    PubMed

    Gosar, Andrej

    2014-01-01

    Two moderate magnitude (Mw = 5.6 and 5.2) earthquakes in Krn Mountains occurred in 1998 and 2004 which had maximum intensity VII-VIII and VI-VII EMS-98, respectively. Comparison of both macroseismic fields showed unexpected differences in the epicentral area which cannot be explained by site effects. Considerably, different distribution of the highest intensities can be noticed with respect to the strike of the seismogenic fault and in some localities even higher intensities have been estimated for the smaller earthquake. Although hypocentres of both earthquakes were only 2 km apart and were located on the same seismogenic Ravne fault, their focal mechanisms showed a slight difference: almost pure dextral strike-slip for the first event and a strike-slip with small reverse component on a steep fault plane for the second one. Seismotectonically the difference is explained as an active growth of the Ravne fault at its NW end. The radiation patterns of both events were studied to explain their possible impact on the observed variations in macroseismic fields and damage distribution. Radiation amplitude lobes were computed for three orthogonal directions: radial P, SV, and SH. The highest intensities of both earthquakes were systematically observed in directions of four (1998) or two (2004) large amplitude lobes in SH component (which corresponds mainly to Love waves), which have significantly different orientation for both events. On the other hand, radial P direction, which is almost purely symmetrical for the strike-slip mechanism of 1998 event, showed for the 2004 event that its small reverse component of movement has resulted in a very pronounced amplitude lobe in SW direction where two settlements are located which expressed higher intensities in the case of the 2004 event with respect to the 1998 one. Although both macroseismic fields are very complex due to influences of multiple earthquakes, retrofitting activity after 1998, site effects, and sparse

  16. Analysis of the Impact of Fault Mechanism Radiation Patterns on Macroseismic Fields in the Epicentral Area of 1998 and 2004 Krn Mountains Earthquakes (NW Slovenia)

    PubMed Central

    2014-01-01

    Two moderate magnitude (Mw = 5.6 and 5.2) earthquakes in Krn Mountains occurred in 1998 and 2004 which had maximum intensity VII-VIII and VI-VII EMS-98, respectively. Comparison of both macroseismic fields showed unexpected differences in the epicentral area which cannot be explained by site effects. Considerably, different distribution of the highest intensities can be noticed with respect to the strike of the seismogenic fault and in some localities even higher intensities have been estimated for the smaller earthquake. Although hypocentres of both earthquakes were only 2 km apart and were located on the same seismogenic Ravne fault, their focal mechanisms showed a slight difference: almost pure dextral strike-slip for the first event and a strike-slip with small reverse component on a steep fault plane for the second one. Seismotectonically the difference is explained as an active growth of the Ravne fault at its NW end. The radiation patterns of both events were studied to explain their possible impact on the observed variations in macroseismic fields and damage distribution. Radiation amplitude lobes were computed for three orthogonal directions: radial P, SV, and SH. The highest intensities of both earthquakes were systematically observed in directions of four (1998) or two (2004) large amplitude lobes in SH component (which corresponds mainly to Love waves), which have significantly different orientation for both events. On the other hand, radial P direction, which is almost purely symmetrical for the strike-slip mechanism of 1998 event, showed for the 2004 event that its small reverse component of movement has resulted in a very pronounced amplitude lobe in SW direction where two settlements are located which expressed higher intensities in the case of the 2004 event with respect to the 1998 one. Although both macroseismic fields are very complex due to influences of multiple earthquakes, retrofitting activity after 1998, site effects, and sparse

  17. The 1946 Unimak Tsunami Earthquake Area: revised tectonic structure in reprocessed seismic images and a suspect near field tsunami source

    USGS Publications Warehouse

    Miller, John J.; von Huene, Roland; Ryan, Holly F.

    2014-01-01

    In 1946 at Unimak Pass, Alaska, a tsunami destroyed the lighthouse at Scotch Cap, Unimak Island, took 159 lives on the Hawaiian Islands, damaged island coastal facilities across the south Pacific, and destroyed a hut in Antarctica. The tsunami magnitude of 9.3 is comparable to the magnitude 9.1 tsunami that devastated the Tohoku coast of Japan in 2011. Both causative earthquake epicenters occurred in shallow reaches of the subduction zone. Contractile tectonism along the Alaska margin presumably generated the far-field tsunami by producing a seafloor elevation change. However, the Scotch Cap lighthouse was destroyed by a near-field tsunami that was probably generated by a coeval large undersea landslide, yet bathymetric surveys showed no fresh large landslide scar. We investigated this problem by reprocessing five seismic lines, presented here as high-resolution graphic images, both uninterpreted and interpreted, and available for the reader to download. In addition, the processed seismic data for each line are available for download as seismic industry-standard SEG-Y files. One line, processed through prestack depth migration, crosses a 10 × 15 kilometer and 800-meter-high hill presumed previously to be basement, but that instead is composed of stratified rock superimposed on the slope sediment. This image and multibeam bathymetry illustrate a slide block that could have sourced the 1946 near-field tsunami because it is positioned within a distance determined by the time between earthquake shaking and the tsunami arrival at Scotch Cap and is consistent with the local extent of high runup of 42 meters along the adjacent Alaskan coast. The Unimak/Scotch Cap margin is structurally similar to the 2011 Tohoku tsunamigenic margin where a large landslide at the trench, coeval with the Tohoku earthquake, has been documented. Further study can improve our understanding of tsunami sources along Alaska’s erosional margins.

  18. Ground breakage and associated effects in the Cook Inlet area, Alaska, resulting from the March 27, 1964 earthquake: Chapter F in The Alaska earthquake, March 27, 1964: regional effects

    USGS Publications Warehouse

    Foster, Helen L.; Karlstrom, Thor N.V.

    1967-01-01

    The great 1964 Alaska earthquake caused considerable ground breakage in the Cook Inlet area of south-central Alaska. The breakage occurred largely in thick deposits of unconsolidated sediments. The most important types of ground breakage were (1) fracturing or cracking and the extrusion of sand and gravel with ground water along fractures in various types of landforms, and (2) slumping and lateral extension of unconfined faces, particularly along delta fronts. The principal concentration of ground breakage within the area covered by this report was in a northeast-trending zone about 60 miles long and 6 miles wide in the northern part of the Kenai Lowland. The zone cut across diverse topography and stratigraphy. Cracks were as much as 30 feet across and 25 feet deep. Sand, gravel, and pieces of coal and lignite were extruded along many fissures. It is suggested that the disruption in this zone may be due to movement along a fault in the underlying Tertiary rocks. The outwash deltas of Tustumena and Skilak Lakes in the Kenai Lowland, of Eklutna Lake and Lake George in the Chugach Mountains, of Bradley Lake in the Kenai Mountains, and at the outlet of upper Beluga Lake at the base of the Alaska Range showed much slumping, as did the delta of the Susitna River. Parts of the flood plains of the Skilak River, Fox River, and Eagle River were extensively cracked. A few avalanches and slumps occurred along the coast of Cook Inlet in scattered localities. Some tidal flats were cracked. However, in view of the many thick sections of unconsolidated sediments and the abundance of steep slopes, the cracking was perhaps less than might have been expected. Observations along the coasts indicated changes in sea level which, although caused partly by compaction of unconsolidated sediments, may largely be attributed to crus1tal deformation accompanying the earthquake. Most of the Cook Inlet area was downwarped, although the northwest side of Cook Inlet may have been slightly unwarped

  19. Sun, Moon and Earthquakes

    NASA Astrophysics Data System (ADS)

    Kolvankar, V. G.

    2013-12-01

    During a study conducted to find the effect of Earth tides on the occurrence of earthquakes, for small areas [typically 1000km X1000km] of high-seismicity regions, it was noticed that the Sun's position in terms of universal time [GMT] shows links to the sum of EMD [longitude of earthquake location - longitude of Moon's foot print on earth] and SEM [Sun-Earth-Moon angle]. This paper provides the details of this relationship after studying earthquake data for over forty high-seismicity regions of the world. It was found that over 98% of the earthquakes for these different regions, examined for the period 1973-2008, show a direct relationship between the Sun's position [GMT] and [EMD+SEM]. As the time changes from 00-24 hours, the factor [EMD+SEM] changes through 360 degree, and plotting these two variables for earthquakes from different small regions reveals a simple 45 degree straight-line relationship between them. This relationship was tested for all earthquakes and earthquake sequences for magnitude 2.0 and above. This study conclusively proves how Sun and the Moon govern all earthquakes. Fig. 12 [A+B]. The left-hand figure provides a 24-hour plot for forty consecutive days including the main event (00:58:23 on 26.12.2004, Lat.+3.30, Long+95.980, Mb 9.0, EQ count 376). The right-hand figure provides an earthquake plot for (EMD+SEM) vs GMT timings for the same data. All the 376 events including the main event faithfully follow the straight-line curve.

  20. High-resolution seismic reflection surveys and modeling across an area of high damage from the 1994 Northridge earthquake, Sherman Oaks, California

    USGS Publications Warehouse

    Stephenson, William J.; Williams, Robert A.; Odum, Jack K.; Worley, David M.

    2000-01-01

    Approximately 3.6 km of P-wave seismic-reflection data were acquired along two orthogonal profiles in Sherman Oaks, California to determine whether shallow (less than 1-km depth) geologic structures contributed to the dramatic localized damage resulting from the 1994 Northridge earthquake. Both lines, one along Matilija Avenue and one along Milbank Street, crossed areas of both high and low damage. We believe these data reveal a geologic structure in the upper 600 m that contributed to the increased earthquake ground shaking in the high-damage areas south of and along the Los Angeles River. Of interest in these data is a reflection interpreted to be from bedrock that can be traced to the north along the Matilija Avenue profile. This reflecting interface, dipping northward at 15°–22°, may be an important impedance boundary because it is the lower boundary of a wedge of overlying low-velocity sediments. The wedge thins and terminates in the area where we interpret down-warped reflections as evidence of a shallow subbasin. The low-velocity subbasin sediments (Vs of 200 m/sec Vp of 500 m/sec) may be up to 150 m thick beneath the channelized Los Angeles River. The area across the subbasin experienced greater earthquake damage from possible geometric focusing effects. Three-dimensional basin effects may be responsible for the variable damage pattern, but from these seismic profiles it is not possible to determine the regional structural trends. Two-dimensional elastic and SH-mode finite-difference modeling of the imaged structural geometry along Matilija Avenue suggests that a peak horizontal-velocity amplification factor of two-and-over can be explained in the high-damage area above the shallow subbasin and sediment wedge. Amplification factors up to 5 were previously observed in aftershock data, at frequencies of 2 to 6 Hz. Amplification in the elastic simulation at the Santa Monica Mountains range-front on the southern end of the Matilija profile, with the

  1. High-resolution seismic imaging of the Mw5.7, 2002 Molise, southern Italy, earthquake area: Evidence of deep fault reactivation

    NASA Astrophysics Data System (ADS)

    Latorre, Diana; Amato, Alessandro; Chiarabba, Claudio

    2010-08-01

    We investigate the seismic structure of the Mw5.7, 2002 Molise earthquake area in order to understand the role of E-W trending strike-slip faults in the tectonics of the southern Apennines. We apply an innovative seismic migration technique to a high quality data set of earthquakes recorded at a dense local network. SP-converted waves are migrated in depth to image the high impedance contrast of the Apulian Platform top buried under the Apennines allochthonous cover. The continuity of the migrated seismic horizon is broken by vertical steps that we systematically picked along 200 cross sections. The best location points of these structures define two main tectonic features. The first one is related to NW-SE oriented normal faults and is consistent with the SW flexure of the foreland lithosphere beneath the orogenic belt. The second one indicates that shallow E-W oriented trans-tensional faults are concentrated directly above the deeper (10-20 km) strike-slip fault, delineating the geometry of a negative flower-type structure. This fault system delimits a depressed sector of the Apulian Platform, whose geometry is consistent with a pull-apart basin inherited from a previous left-lateral strike-slip tectonic regime. The buried structure is analogous to those outcropping in the Apulian foreland and in the Adriatic offshore, to the east. This correlation brings new support to the hypothesis of a regional E-W trending shear zone cutting the Adria plate and suggests that other earthquakes could occur on this or on parallel E-W trending strike-slip faults.

  2. [Survey report on magnetic resonance equipment damage in areas in Miyagi Prefecture affected by the Great East Japan Earthquake].

    PubMed

    Maeyatsu, Fumio; Abe, Yoshihiro; Hishinuma, Makoto; Hikiti, Takeo; Tanji, Hajime; Seino, Shinya; Adachi, Kojiro; Musashi, Yasunori; Tuchihashi, Toshio; Machida, Yosihio; Yamaguchi-Sekino, Sachiko; Nakai, Toshiharu

    2014-03-01

    A questionnaire comprising 14 items, inquiring about the state of damage, whether safety could be ensured, and progress of repair and restoration was distributed to 984 facilities in seven prefectures on the Pacific coast as part of a fact-finding survey of damage caused to magnetic resonance (MR) devices by the Great East Japan Earthquake. In all, 458 responses (46.6%) were collected. In Miyagi Prefecture alone, 65 responses from 105 questionnaires were collected (response rate: 61.9%). The overall incidence of damage was 19.2%, with 57 facilities (12.4%) reporting that displacement of the magnets was the most common problem. The damage event rate in Miyagi Prefecture was 51.3%, with displacement of the magnet being highest at 17 cases (26.2%). There was a high rate of 13 cases (26.5%) of chiller and air conditioning failures and a rapid loss of He in ten MR scanners (20.4%). Notably, 87.8% of facilities in Miyagi Prefecture (24.5% of the total) were affected by earthquakes exceeding 6 on the Japanese Seismic Intensity Scale. Flood damage caused by the tsunami was also seen along the Sanriku coast to Sendai City (six MR scanners, 50% of the total), and was typical of the damage seen in Miyagi Prefecture.

  3. [Survey report on magnetic resonance equipment damage in areas in Miyagi Prefecture affected by the Great East Japan Earthquake].

    PubMed

    Maeyatsu, Fumio; Abe, Yoshihiro; Hishinuma, Makoto; Hikiti, Takeo; Tanji, Hajime; Seino, Shinya; Adachi, Kojiro; Musashi, Yasunori; Tuchihashi, Toshio; Machida, Yosihio; Yamaguchi-Sekino, Sachiko; Nakai, Toshiharu

    2014-03-01

    A questionnaire comprising 14 items, inquiring about the state of damage, whether safety could be ensured, and progress of repair and restoration was distributed to 984 facilities in seven prefectures on the Pacific coast as part of a fact-finding survey of damage caused to magnetic resonance (MR) devices by the Great East Japan Earthquake. In all, 458 responses (46.6%) were collected. In Miyagi Prefecture alone, 65 responses from 105 questionnaires were collected (response rate: 61.9%). The overall incidence of damage was 19.2%, with 57 facilities (12.4%) reporting that displacement of the magnets was the most common problem. The damage event rate in Miyagi Prefecture was 51.3%, with displacement of the magnet being highest at 17 cases (26.2%). There was a high rate of 13 cases (26.5%) of chiller and air conditioning failures and a rapid loss of He in ten MR scanners (20.4%). Notably, 87.8% of facilities in Miyagi Prefecture (24.5% of the total) were affected by earthquakes exceeding 6 on the Japanese Seismic Intensity Scale. Flood damage caused by the tsunami was also seen along the Sanriku coast to Sendai City (six MR scanners, 50% of the total), and was typical of the damage seen in Miyagi Prefecture. PMID:24647061

  4. Cross‐species chimeras reveal BamA POTRA and β‐barrel domains must be fine‐tuned for efficient OMP insertion

    PubMed Central

    Bavro, Vassiliy N.; Mason, Jessica L.; Sevastsyanovich, Yanina R.; Rossiter, Amanda E.; Jeeves, Mark; Wells, Timothy J.; Knowles, Timothy J.; Cunningham, Adam F.; Donald, James W.; Palmer, Tracy; Overduin, Michael

    2015-01-01

    Summary BAM is a conserved molecular machine, the central component of which is BamA. Orthologues of BamA are found in all Gram‐negative bacteria, chloroplasts and mitochondria where it is required for the folding and insertion of β‐barrel containing integral outer membrane proteins (OMPs) into the outer membrane. BamA binds unfolded β‐barrel precursors via the five polypeptide transport‐associated (POTRA) domains at its N‐terminus. The C‐terminus of BamA folds into a β‐barrel domain, which tethers BamA to the outer membrane and is involved in OMP insertion. BamA orthologues are found in all Gram‐negative bacteria and appear to function in a species‐specific manner. Here we investigate the nature of this species‐specificity by examining whether chimeric E scherichia coli  BamA fusion proteins, carrying either the β‐barrel or POTRA domains from various BamA orthologues, can functionally replace E . coli  BamA. We demonstrate that the β‐barrel domains of many BamA orthologues are functionally interchangeable. We show that defects in the orthologous POTRA domains can be rescued by compensatory mutations within the β‐barrel. These data reveal that the POTRA and barrel domains must be precisely aligned to ensure efficient OMP insertion. PMID:25943387

  5. The search for repeating earthquakes in the northern San Francisco Bay area Nader Shakibay Senobari and Gareth J. Funning University of California, Riverside

    NASA Astrophysics Data System (ADS)

    Shakibay Senobari, N.; Funning, G.

    2013-12-01

    Repeating earthquakes (REs) are sequences of identical repeating events, which are recurring either irregularly (aperiodic) or nearly regularly (quasi-periodic). There are two important characteristics of the events in a RE sequence: they have the same source characteristics (i.e. magnitude and mechanism) and they have the same location and therefore their waveforms at the same stations are extremely similar. Several authors have proposed that the quasi-periodic REs result from recurrent rupture of a small locked patch on a fault surface surrounded by a larger area of creep. The implication is that any detection of characteristic REs along a fault can be interpreted as a signature of the creep at depth on that fault. In addition, REs can be used for locating faults and determining their geometries at depth. In this study, we are looking for REs on the northern Rodgers Creek and southern Maacama faults near Santa Rosa, CA. There is some observational evidence for creep along portions of these faults (e.g. from InSAR, alignment arrays and offset cultural features) but the depth of creep on both faults is still unknown. Finding the locations of REs in this area, and combining them with geodetic data, will help us to place stronger constraints on the distributions of aseismic slip on both the Rodgers Creek and Maacama faults. In order to identify such events, we use data from the Northern California Seismic Network (NCSN) for the period from 1984 to July 2013. We used earthquake waveforms from 2080 events located inside a 25 by 30 km area around Santa Rosa. We choose 7 stations located both inside and outside the selection area at distances of up to 50 km. We calculate the coherence for all pairs of events for each station during the time that the sensor has not been changed (mostly from 1987 to 2013). We align the waveforms using P arrival times from the NCSN catalog. The time windows for the seismogram analysis are set at 0.2 sec before and 10.2 sec after the P

  6. Effects of the earthquake of March 27, 1964, in the Homer area, Alaska, with a section on beach changes on Homer Spit: Chapter D in The Alaska earthquake, March 27, 1964: effects on communities

    USGS Publications Warehouse

    Waller, Roger M.; Stanley, Kirk W.

    1966-01-01

    The March 27, 1964, earthquake shook the Homer area for about 3 minutes. Land effects consisted of a 2- to 6-foot subsidence of the mainland and Homer Spit, one earthflow at the mouth of a canyon, several landslides on the Homer escarpment and along the sea bluffs, and minor fissuring of the ground, principally at the edges of bluffs and on Homer Spit. Hydrologic effects consisted of at least one and possibly two submarine landslides at the end of the spit, seiche waves in Kachemak Bay, ice breakage on Beluga Lake, sanding of wells, and a temporary loss of water in some wells. Seismic damage to the community was light in comparison with that of other communities closer to the epicenter. One submarine landslide, however, took out most of the harbor breakwater. The greatest damage was due to the subsidence of the spit, both tectonically (2–3 ft) and by differential compaction or lateral spreading (an additional 1–4 ft). Higher tides now flood much of the spit. The harbor and dock had to be replaced, and buildings on the end of the spit had to be elevated. Protection works for other buildings and the highway were needed. These works included application of fill to raise the highway and parts of the spit above high tides. Reconstruction costs and disaster loans totaled about $2½ million, but this amount includes added improvement costs over preexisting values. Homer Spit in particular and the Homer area in general rank as areas where precautions must be taken in selecting building sites. The hazards of landslides, earthflows, compaction and submarine slumping—all of which might be triggered by an earthquake—should be considered in site selection. In plan, Homer Spit resembles a scimitar with its curving blade pointed seaward. It is about 4 miles long and as much as 1,500 feet wide. The spit is composed largely of gravel intermixed with some sand. After the earthquake and the resulting tectonic subsidence and compaction, much of the spit was below high

  7. Hidden earthquakes

    SciTech Connect

    Stein, R.S.; Yeats, R.S.

    1989-06-01

    Seismologists generally look for earthquakes to happen along visible fault lines, e.g., the San Andreas fault. The authors maintain that another source of dangerous quakes has been overlooked: the release of stress along a fault that is hidden under a fold in the earth's crust. The paper describes the differences between an earthquake which occurs on a visible fault and one which occurs under an anticline and warns that Los Angeles greatest earthquake threat may come from a small quake originating under downtown Los Angeles, rather than a larger earthquake which occurs 50 miles away at the San Andreas fault.

  8. Inference of small-scale Vp/Vs ratio along the rupture area of the Tocopilla earthquake, Northern Chile (Mw 7.7, 14/11/2007)

    NASA Astrophysics Data System (ADS)

    Tilmann, F. J.; Palo, M.; Schurr, B.

    2014-12-01

    We have inferred the Vp/Vs ratio along the segment of the Peru-Chile subduction margin corresponding to the rupture area of the Tocopilla earthquake (TE, Mw 7.7, 14/11/2007). This event nucleated in Northern Chile and broke the southern ~100 km of the ~500 km Northern Chile Southern Peru seismic gap, which had not seen an earthquake of this magnitude since the M~9 event of 1877. TE activated two main co-seismic slip patches: one around the epicenter and another north-east of the Mejillones Peninsula. We have applied the Lin and Shearer approach [1] to the aftershock sequence of TE. In this approach, the relative time shift between the S phases of a pair of nearby events at one station are plotted as function of the time shift between the P phases of the same pair. The process is repeated for a set of events. If the events are close enough to assume a uniform local Vp/Vs and the P-reciprocal wavefront can be approximated as planar, the points lay on a line, whose slope is an estimation of the local Vp/Vs. The technique is extended to a set of stations demeaning the time shifts from each pair of events. The time shifts are inferred maximizing the cross-correlation function between the event pairs. The technique has been applied to clusters of events sharing similar waveforms and spatially clustered hypocentres. We have adopted a robust linear L2 regression and have assigned a statistical error to the best fit. Most clusters are identified within a sub-vertical branch of the subduction interface hosting a major aftershock (Michilla earthquake, 16/12/2007, Ml 6.8) and its aftershocks. This branch falls inside the subducted Nazca Plate at depths of 40-50 km, north-east of the Mejillones Peninsula, and shows Vp/Vs mostly in the range 1.8-1.9. Clusters close to the Mejillones Peninsula and to the epicenter displays Vp/Vs around 1.7 and 1.8, respectively. References [1] - Lin, G., & Shearer, P. (2007). Estimating local Vp/Vs ratios within similar earthquake clusters

  9. The Damaging Effects of Earthquake Excitation on Concrete Cooling Towers

    SciTech Connect

    Abedi-Nik, Farhad; Sabouri-Ghomi, Saeid

    2008-07-08

    Reinforced concrete cooling towers of hyperbolic shell configuration find widespread application in utilities engaged in the production of electric power. In design of critical civil infrastructure of this type, it is imperative to consider all the possible loading conditions that the cooling tower may experience, an important loading condition in many countries is that of the earthquake excitation, whose influence on the integrity and stability of cooling towers is profound. Previous researches have shown that the columns supporting a cooling tower are sensitive to earthquake forces, as they are heavily loaded elements that do not possess high ductility, and understanding the behavior of columns under earthquake excitation is vital in structural design because they provide the load path for the self weight of the tower shell. This paper presents the results of a finite element investigation of a representative 'dry' cooling tower, using realistic horizontal and vertical acceleration data obtained from the recent and widely-reported Tabas, Naghan and Bam earthquakes in Iran. The results of both linear and nonlinear analyses are reported in the paper, the locations of plastic hinges within the supporting columns are identified and the ramifications of the plastic hinges on the stability of the cooling tower are assessed. It is concluded that for the (typical) cooling tower configuration analyzed, the columns that are instrumental in providing a load path are influenced greatly by earthquake loading, and for the earthquake data used in this study the representative cooling tower would be rendered unstable and would collapse under the earthquake forces considered.

  10. Deep electrical resistivity tomography along the tectonically active Middle Aterno Valley (2009 L'Aquila earthquake area, central Italy)

    NASA Astrophysics Data System (ADS)

    Pucci, Stefano; Civico, Riccardo; Villani, Fabio; Ricci, Tullio; Delcher, Eric; Finizola, Anthony; Sapia, Vincenzo; De Martini, Paolo Marco; Pantosti, Daniela; Barde-Cabusson, Stéphanie; Brothelande, Elodie; Gusset, Rachel; Mezon, Cécile; Orefice, Simone; Peltier, Aline; Poret, Matthieu; Torres, Liliana; Suski, Barbara

    2016-11-01

    Three 2-D Deep Electrical Resistivity Tomography (ERT) transects, up to 6.36 km long, were obtained across the Paganica-San Demetrio Basin, bounded by the 2009 L'Aquila Mw 6.1 normal-faulting earthquake causative fault (central Italy). The investigations allowed defining for the first time the shallow subsurface basin structure. The resistivity images, and their geological interpretation, show a dissected Mesozoic-Tertiary substratum buried under continental infill of mainly Quaternary age due to the long-term activity of the Paganica-San Demetrio normal faults system (PSDFS), ruling the most recent deformational phase. Our results indicate that the basin bottom deepens up to 600 m moving to the south, with the continental infill largely exceeding the known thickness of the Quaternary sequence. The causes of this increasing thickness can be: (1) the onset of the continental deposition in the southern sector took place before the Quaternary, (2) there was an early stage of the basin development driven by different fault systems that produced a depocentre in the southern sector not related to the present-day basin shape, or (3) the fault system slip rate in the southern sector was faster than in the northern sector. We were able to gain sights into the long-term PSDFS behaviour and evolution, by comparing throw rates at different timescales and discriminating the splays that lead deformation. Some fault splays exhibit large cumulative throws (>300 m) in coincidence with large displacement of the continental deposits sequence (>100 m), thus testifying a general persistence in time of their activity as leading splays of the fault system. We evaluate the long-term (3-2.5 Myr) cumulative and Quaternary throw rates of most of the leading splays to be 0.08-0.17 mm yr-1, indicating a substantial stability of the faults activity. Among them, an individual leading fault splay extends from Paganica to San Demetrio ne' Vestini as a result of a post-Early Pleistocene linkage of

  11. Earthquakes with non--double-couple mechanisms.

    PubMed

    Frohlich, C

    1994-05-01

    Seismological observations confirm that the pattern of seismic waves from some earthquakes cannot be produced by slip along a planar fault surface. More than one physical mechanism is required to explain the observed varieties of these non-double-couple earthquakes. The simplest explanation is that some earthquakes are complex, with stress released on two or more suitably oriented, nonparallel fault surfaces. However, some shallow earthquakes in volcanic and geothermal areas require other explanations. Current research focuses on whether fault complexity explains most observed non-double-couple earthquakes and to what extent ordinary earthquakes have non-double-couple components.

  12. Symptoms of posttraumatic stress disorder, depression, and anxiety among junior high school students in worst-hit areas 3 years after the Wenchuan earthquake in China.

    PubMed

    Pan, Xiao; Liu, Weizhi; Deng, Guanghui; Liu, Taosheng; Yan, Jin; Tang, Yunxiang; Dong, Wei; Cui, Yi; Xu, Miao

    2015-03-01

    The aim of this study was to examine symptoms of posttraumatic stress disorder (PTSD), depression, and anxiety among junior high school students in worst-hit areas 3 years after the Wenchuan earthquake. Analyses were carried out on 373 of the 377 students enrolled. In addition to obtaining demographic characteristics, the Impact of Event Scale-Revised, the Zung Self-rating Depression Scale, the Zung Self-rating Anxiety Scale, and an Earthquake exposure screening scale were administered. It was found that 29.6%, 44.8%, and 37.6% of participants reported clinical symptoms of PTSD, depression, and anxiety, respectively. PTSD, depression, and anxiety were highly comorbid. Having witnessed someone being killed, family members being killed, close friends seriously injured or being killed, and felt scared remained as significant predictors for PTSD. Having witnessed someone seriously injured and felt scared remained as significant predictors for depression. Having witnessed someone seriously injured, witnessed someone being killed, and felt scared remained as significant predictors for anxiety.

  13. P and S waves tomographic analysis of the area of El Asnam's 1980 ms 7.3 earthquake (Algeria) from its aftershock sequence

    NASA Astrophysics Data System (ADS)

    Bellalem, F.; Bounif, M. A.; Koulakov, I.

    2015-01-01

    We present the 3D seismic model of crustal structure and the distribution of seismicity in the El Asnam region (Algeria) where a strong earthquake (M7.3) occurred in 1980. We apply the local earthquake tomography inversion for the data of temporary networks which recorded the aftershocks of the 1980 event. The results of the tomography inversion have been rigorously tested using a number of different tests. The velocity anomalies from the inversion show pronounced low-velocity anomalies in the surface rupture zone associated with El Asnam fault, which are consistent with the finding of the previous studies (Philip and Meghraoui Tectonics 2:17-49, 1983), Ouyed et al. (Nature 292:26-31, 1981). Moreover, we have also reported the high velocities that exist at shallow crustal depths in the El Asnam zone. We have associated this feature to tectonic, geomorphological, and structural settings in the study area. Finally, we hope that the main features of the interpretation summarized in this article will be the basis for further integrated geophysical and tectonic analyses.

  14. Prospective Study on the Effectiveness of Complementary Food Supplements on Improving Status of Elder Infants and Young Children in the Areas Affected by Wenchuan Earthquake

    PubMed Central

    Dong, Caixia; Ge, Pengfei; Ren, Xiaolan; Wang, Jie; Fan, Haoqiang; Yan, Xiang; Yin, Shi-an

    2013-01-01

    Objective To prospectively evaluate the efficiency of daily providing complementary food supplements decreasing malnutrition and anemia prevalence in elder infants and young children living in areas affected by Wenchuan Earthquake. Design Using promotional probability sampling method, 250 to 300 children from six-randomized townships (30 to 50 children in each township) in Kang County affected by the Earthquake were randomly chosen for follow up to evaluate intervention effectiveness using anthropometric measurement and hemoglobin level at six, twelve and eighteen months after start of intervention. Setting and Subjects All children from 6 to 18 months of age in Kang County (in North Western China) were daily provided with complementary food supplements containing multiple vitamins and minerals for up to 24 months of age. The intervention period lasted for one and half year. Results At beginning of intervention, malnutrition prevalence, including underweight, stunting and wasting were respectively 4.5%, 8.9% and 3.5%; anemia prevalence was 74.3%. After one and half year intervention, the growth and anemia status were significantly improved; the percentages of wasting, stunting underweight prevalence were decreased from 3.5%, 8.9% and 4.5% to 1.7%, 5.0% and 3.3% respectively, and the anemia rates were significantly decreased. Conclusions Our results indicated that an intervention using complementary food supplements could improve nutritional status and elevate hemoglobin level in elder infants and young children, which would significantly decrease the prevalence of malnutrition and anemia. PMID:24039797

  15. Earthquakes in the United States

    USGS Publications Warehouse

    Stover, C.

    1977-01-01

    To supplement data in the report Preliminary Determination of Epicenters (PDE), the National earthquake Information Service (NEIS) also publishes a quarterly circular, Earthquakes in the United States. This provides information on the felt area of U.S earthquakes and their intensity. The main purpose is to describe the larger effects of these earthquakes so that they can be used in seismic risk studies, site evaluations for nuclear power plants, and answering inquiries by the general public.

  16. Existence and global exponential stability of periodic solution of memristor-based BAM neural networks with time-varying delays.

    PubMed

    Li, Hongfei; Jiang, Haijun; Hu, Cheng

    2016-03-01

    In this paper, we investigate a class of memristor-based BAM neural networks with time-varying delays. Under the framework of Filippov solutions, boundedness and ultimate boundedness of solutions of memristor-based BAM neural networks are guaranteed by Chain rule and inequalities technique. Moreover, a new method involving Yoshizawa-like theorem is favorably employed to acquire the existence of periodic solution. By applying the theory of set-valued maps and functional differential inclusions, an available Lyapunov functional and some new testable algebraic criteria are derived for ensuring the uniqueness and global exponential stability of periodic solution of memristor-based BAM neural networks. The obtained results expand and complement some previous work on memristor-based BAM neural networks. Finally, a numerical example is provided to show the applicability and effectiveness of our theoretical results.

  17. Earthquake Hazards.

    ERIC Educational Resources Information Center

    Donovan, Neville

    1979-01-01

    Provides a survey and a review of earthquake activity and global tectonics from the advancement of the theory of continental drift to the present. Topics include: an identification of the major seismic regions of the earth, seismic measurement techniques, seismic design criteria for buildings, and the prediction of earthquakes. (BT)

  18. Earthquake prediction

    NASA Technical Reports Server (NTRS)

    Turcotte, Donald L.

    1991-01-01

    The state of the art in earthquake prediction is discussed. Short-term prediction based on seismic precursors, changes in the ratio of compressional velocity to shear velocity, tilt and strain precursors, electromagnetic precursors, hydrologic phenomena, chemical monitors, and animal behavior is examined. Seismic hazard assessment is addressed, and the applications of dynamical systems to earthquake prediction are discussed.

  19. Analog earthquakes

    SciTech Connect

    Hofmann, R.B.

    1995-09-01

    Analogs are used to understand complex or poorly understood phenomena for which little data may be available at the actual repository site. Earthquakes are complex phenomena, and they can have a large number of effects on the natural system, as well as on engineered structures. Instrumental data close to the source of large earthquakes are rarely obtained. The rare events for which measurements are available may be used, with modfications, as analogs for potential large earthquakes at sites where no earthquake data are available. In the following, several examples of nuclear reactor and liquified natural gas facility siting are discussed. A potential use of analog earthquakes is proposed for a high-level nuclear waste (HLW) repository.

  20. Arabidopsis MAKR5 is a positive effector of BAM3-dependent CLE45 signaling.

    PubMed

    Kang, Yeon Hee; Hardtke, Christian S

    2016-08-01

    Receptor kinases convey diverse environmental and developmental inputs by sensing extracellular ligands. In plants, one group of receptor-like kinases (RLKs) is characterized by extracellular leucine-rich repeat (LRR) domains, which interact with various ligands that include the plant hormone brassinosteroid and peptides of the CLAVATA3/EMBRYO SURROUNDING REGION (CLE) type. For instance, the CLE45 peptide requires the LRR-RLK BARELY ANY MERISTEM 3 (BAM3) to prevent protophloem formation in Arabidopsis root meristems. Here, we show that other proposed CLE45 receptors, the two redundantly acting LRR-RLKs STERILITY-REGULATING KINASE MEMBER 1 (SKM1) and SKM2 (which perceive CLE45 in the context of pollen tube elongation), cannot substitute for BAM3 in the root. Moreover, we identify MEMBRANE-ASSOCIATED KINASE REGULATOR 5 (MAKR5) as a post-transcriptionally regulated amplifier of the CLE45 signal that acts downstream of BAM3. MAKR5 belongs to a small protein family whose prototypical member, BRI1 KINASE INHIBITOR 1, is an essentially negative regulator of brassinosteroid signaling. By contrast, MAKR5 is a positive effector of CLE45 signaling, revealing an unexpected diversity in the conceptual roles of MAKR genes in different signaling pathways. PMID:27354416

  1. Lipids assist the membrane insertion of a BAM-independent outer membrane protein

    PubMed Central

    Huysmans, Gerard H. M.; Guilvout, Ingrid; Chami, Mohamed; Nickerson, Nicholas N.; Pugsley, Anthony P.

    2015-01-01

    Like several other large, multimeric bacterial outer membrane proteins (OMPs), the assembly of the Klebsiella oxytoca OMP PulD does not rely on the universally conserved β-barrel assembly machinery (BAM) that catalyses outer membrane insertion. The only other factor known to interact with PulD prior to or during outer membrane targeting and assembly is the cognate chaperone PulS. Here, in vitro translation-transcription coupled PulD folding demonstrated that PulS does not act during the membrane insertion of PulD, and engineered in vivo site-specific cross-linking between PulD and PulS showed that PulS binding does not prevent membrane insertion. In vitro folding kinetics revealed that PulD is atypical compared to BAM-dependent OMPs by inserting more rapidly into membranes containing E. coli phospholipids than into membranes containing lecithin. PulD folding was fast in diC14:0-phosphatidylethanolamine liposomes but not diC14:0-phosphatidylglycerol liposomes, and in diC18:1-phosphatidylcholine liposomes but not in diC14:1-phosphatidylcholine liposomes. These results suggest that PulD efficiently exploits the membrane composition to complete final steps in insertion and explain how PulD can assemble independently of any protein-assembly machinery. Lipid-assisted assembly in this manner might apply to other large OMPs whose assembly is BAM-independent. PMID:26463896

  2. State of Stress in the Interseismic in the Salar Grande Area and its Relationship with the Foreshock Sequence of Mw8.1 Pisagua Earthquake

    NASA Astrophysics Data System (ADS)

    Salazar, P.; Gonzalez, G.; Latorre, C.; Pasten, F.; Sarmiento, A.; Kummerow, J.; Wigger, P.; Bloch, W.; Shapiro, S. A.

    2014-12-01

    We have installed short period network in order to monitor the crustal seismicity in the Tarapacá region. The main task is to try to understand the stress transference from the interplate contact to the upper crustal. The network consisted in a total of 21 short period stations, which were installed in the Coastal Cordillera (around Salar Grande) and the Precordillera (around Quebrada Blanca). The processing of the records in this network permitted the analysis of ~5000 events occurred during 2005-2012, each were localized using the NonLinLoc software. A part of this catalog, specifically the data collected during 2010, were processed in order to obtain some parameters associated to the stress as stress tensor, b-value and the maximum horizontal stress (σHMAX). The results of the σHMAX and the stress tensor show that the direction of shortening in the upper crust is NS, which is clearly deviated from the direction of convergence. This pattern, found in the Salar Grande, is practically the same that we observed in the Mw6.7 earthquake occurred on March 16th -event that triggered the sequence of foreshock associated to the Mw8.1 Pisagua earthquake (ca. 170 km to the NW of the Salar Grande area). The NS direction of shortening is also seen in several upper crustal events occurred in the first days, before Mw8.1 Pisagua earthquake. On the other hand, the b-value > 0.9, calculated for the Salar Grande area, coincides with places where the seismic activity is associated to EW reverse faults mapped in the surface by geological studies -these structures are a common feature in the Atacama Fault System at these latitudes. They are also an indication of a NS direction of shortening, being in agreement with our seismological observations. The NS direction of shortening is not restricted to shallow depth, but it is extended to the interplate contact between the deeper part of the couple zone and the transitional zone. The last indicates that the NS shortening is a

  3. Investigation of the role of the BAM complex and SurA chaperone in outer-membrane protein biogenesis and type III secretion system expression in Salmonella.

    PubMed

    Fardini, Yann; Trotereau, Jérôme; Bottreau, Elisabeth; Souchard, Charlène; Velge, Philippe; Virlogeux-Payant, Isabelle

    2009-05-01

    In Escherichia coli, the assembly of outer-membrane proteins (OMP) requires the BAM complex and periplasmic chaperones, such as SurA or DegP. Previous work has suggested a potential link between OMP assembly and expression of the genes encoding type-III secretion systems. In order to test this hypothesis, we studied the role of the different lipoproteins of the BAM complex (i.e. BamB, BamC, BamD and BamE), and the periplasmic chaperones SurA and DegP, in these two phenotypes in Salmonella. Analysis of the corresponding deletion mutants showed that, as previously described with the DeltabamB mutant, BamD, SurA and, to a lesser extent, BamE play a role in outer-membrane biogenesis in Salmonella Enteritidis, while the membrane was not notably disturbed in DeltabamC and DeltadegP mutants. Interestingly, we found that BamD is not essential in Salmonella, unlike its homologues in Escherichia coli and Neisseria gonorrhoeae. In contrast, BamD was the only protein required for full expression of T3SS-1 and flagella, as demonstrated by transcriptional analysis of the genes involved in the biosynthesis of these T3SSs. In line with this finding, bamD mutants showed a reduced secretion of effector proteins by these T3SSs, and a reduced ability to invade HT-29 cells. As DeltasurA and DeltabamE mutants had lower levels of OMPs in their outer membrane, but showed no alteration in T3SS-1 and flagella expression, these results demonstrate the absence of a systematic link between an OMP assembly defect and the downregulation of T3SSs in Salmonella; therefore, this link appears to be related to a more specific mechanism that involves at least BamB and BamD. PMID:19372159

  4. Nisqually, Washington Intraplate Earthquake

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Hofmeister, R.

    2001-05-01

    On February 28, 2001, the M6.8 Nisqually earthquake shook the Pacific Northwest. This intraplate event occurred within the subducting Juan de Fuca plate along the Cascadia margin. Although the damage was less than observed at most large urban earthquakes, serious damage was found in Olympia, Seattle, and Tacoma. To better serve Oregon public safety needs, DOGAMI and others surveyed the Puget Sound damage to expand our technical understanding of seismic ground response, building and lifeline behavior, and secondary hazards (landslides and liquefaction). Damage was observed in structures and areas that, for the most part, would be predicted to be vulnerable. These included: old buildings (URMs), old lifelines (4th Ave bridge in Olympia), areas with poor soil conditions (Harbor Island, Seattle; Sunset Lake, Tumwater), and steep slopes (Salmon Beach; Burien). Damage types included: structural, nonstructural, contents, lifelines, landslides, liquefaction, lateral spreading, sand boils, and settlement. In several notable places, seismic-induced ground failures significantly increased the damage. Estimated costs developed from HAZUS evaluations ranged from \\2 billion to \\3.9 billion. Historic intraplate earthquakes in the Puget Sound region, including the 1949 M7.1, 1965 M6.5, and 1999 M5.9, were not accompanied by significant aftershock events or associated with earthquake sequences. However, a recent El Salvador earthquake sequence suggests there may be particular cases of increased seismicity following large intraplate events, with implications for post-earthquake response and mitigation. The January 13, 2001 M7.6 El Salvador intraplate earthquake was followed by a M6.6 crustal event February 13, 2001 and a M5.4 intraplate event February 28, 2001.

  5. Turkish Compulsory Earthquake Insurance and "Istanbul Earthquake

    NASA Astrophysics Data System (ADS)

    Durukal, E.; Sesetyan, K.; Erdik, M.

    2009-04-01

    The city of Istanbul will likely experience substantial direct and indirect losses as a result of a future large (M=7+) earthquake with an annual probability of occurrence of about 2%. This paper dwells on the expected building losses in terms of probable maximum and average annualized losses and discusses the results from the perspective of the compulsory earthquake insurance scheme operational in the country. The TCIP system is essentially designed to operate in Turkey with sufficient penetration to enable the accumulation of funds in the pool. Today, with only 20% national penetration, and about approximately one-half of all policies in highly earthquake prone areas (one-third in Istanbul) the system exhibits signs of adverse selection, inadequate premium structure and insufficient funding. Our findings indicate that the national compulsory earthquake insurance pool in Turkey will face difficulties in covering incurring building losses in Istanbul in the occurrence of a large earthquake. The annualized earthquake losses in Istanbul are between 140-300 million. Even if we assume that the deductible is raised to 15%, the earthquake losses that need to be paid after a large earthquake in Istanbul will be at about 2.5 Billion, somewhat above the current capacity of the TCIP. Thus, a modification to the system for the insured in Istanbul (or Marmara region) is necessary. This may mean an increase in the premia and deductible rates, purchase of larger re-insurance covers and development of a claim processing system. Also, to avoid adverse selection, the penetration rates elsewhere in Turkey need to be increased substantially. A better model would be introduction of parametric insurance for Istanbul. By such a model the losses will not be indemnified, however will be directly calculated on the basis of indexed ground motion levels and damages. The immediate improvement of a parametric insurance model over the existing one will be the elimination of the claim processing

  6. Testing an earthquake prediction algorithm

    USGS Publications Warehouse

    Kossobokov, V.G.; Healy, J.H.; Dewey, J.W.

    1997-01-01

    A test to evaluate earthquake prediction algorithms is being applied to a Russian algorithm known as M8. The M8 algorithm makes intermediate term predictions for earthquakes to occur in a large circle, based on integral counts of transient seismicity in the circle. In a retroactive prediction for the period January 1, 1985 to July 1, 1991 the algorithm as configured for the forward test would have predicted eight of ten strong earthquakes in the test area. A null hypothesis, based on random assignment of predictions, predicts eight earthquakes in 2.87% of the trials. The forward test began July 1, 1991 and will run through December 31, 1997. As of July 1, 1995, the algorithm had forward predicted five out of nine earthquakes in the test area, which success ratio would have been achieved in 53% of random trials with the null hypothesis.

  7. The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence

    USGS Publications Warehouse

    Coordinated by Bakun, William H.; Prescott, William H.

    1993-01-01

    Professional Paper 1550 seeks to understand the M6.9 Loma Prieta earthquake itself. It examines how the fault that generated the earthquake ruptured, searches for and evaluates precursors that may have indicated an earthquake was coming, reviews forecasts of the earthquake, and describes the geology of the earthquake area and the crustal forces that affect this geology. Some significant findings were: * Slip during the earthquake occurred on 35 km of fault at depths ranging from 7 to 20 km. Maximum slip was approximately 2.3 m. The earthquake may not have released all of the strain stored in rocks next to the fault and indicates a potential for another damaging earthquake in the Santa Cruz Mountains in the near future may still exist. * The earthquake involved a large amount of uplift on a dipping fault plane. Pre-earthquake conventional wisdom was that large earthquakes in the Bay area occurred as horizontal displacements on predominantly vertical faults. * The fault segment that ruptured approximately coincided with a fault segment identified in 1988 as having a 30% probability of generating a M7 earthquake in the next 30 years. This was one of more than 20 relevant earthquake forecasts made in the 83 years before the earthquake. * Calculations show that the Loma Prieta earthquake changed stresses on nearby faults in the Bay area. In particular, the earthquake reduced stresses on the Hayward Fault which decreased the frequency of small earthquakes on it. * Geological and geophysical mapping indicate that, although the San Andreas Fault can be mapped as a through going fault in the epicentral region, the southwest dipping Loma Prieta rupture surface is a separate fault strand and one of several along this part of the San Andreas that may be capable of generating earthquakes.

  8. Aftershock distribution and heterogeneous structure in and around the source area of the 2014 northern Nagano Prefecture earthquake (Mw 6.2) , central Japan, revealed by dense seismic array observation

    NASA Astrophysics Data System (ADS)

    Kurashimo, E.; Hirata, N.; Iwasaki, T.; Sakai, S.; Obara, K.; Ishiyama, T.; Sato, H.

    2015-12-01

    A shallow earthquake (Mw 6.2) occurred on November 22 in the northern Nagano Prefecture, central Japan. Aftershock area is located near the Kamishiro fault, which is a part of the Itoigawa-Shizuoka Tectonic Line (ISTL). ISTL is one of the major tectonic boundaries in Japan. Precise aftershock distribution and heterogeneous structure in and around the source region of this earthquake is important to constrain the process of earthquake occurrence. We conducted a high-density seismic array observation in and around source area to investigate aftershock distribution and crustal structure. One hundred sixty-three seismic stations, approximately 1 km apart, were deployed during the period from December 3, 2014 to December 21, 2014. Each seismograph consisted of a 4.5 Hz 3-component seismometer and a digital data recorder (GSX-3). Furthermore, the seismic data at 40 permanent stations were incorporated in our analysis. During the seismic array observation, the Japan Meteorological Agency located 977 earthquakes in a latitude range of 35.5°-37.1°N and a longitude range of 136.7°-139.0°E, from which we selected 500 local events distributed uniformly in the study area. To investigate the aftershock distribution and the crustal structure, the double-difference tomography method [Zhang and Thurber, 2003] was applied to the P- and S-wave arrival time data obtained from 500 local earthquakes. The relocated aftershock distribution shows a concentration on a plane dipping eastward in the vicinity of the mainshock hypocenter. The large slip region (asperity) estimated from InSAR analysis [GSI, 2014] corresponds to the low-activity region of the aftershocks. The depth section of Vp structure shows that the high Vp zone corresponds to the large slip region. These results suggest that structural heterogeneities in and around the fault plane may have controlled the rupture process of the 2014 northern Nagano Prefecture earthquake.

  9. Charles Darwin's earthquake reports

    NASA Astrophysics Data System (ADS)

    Galiev, Shamil

    2010-05-01

    As it is the 200th anniversary of Darwin's birth, 2009 has also been marked as 170 years since the publication of his book Journal of Researches. During the voyage Darwin landed at Valdivia and Concepcion, Chile, just before, during, and after a great earthquake, which demolished hundreds of buildings, killing and injuring many people. Land was waved, lifted, and cracked, volcanoes awoke and giant ocean waves attacked the coast. Darwin was the first geologist to observe and describe the effects of the great earthquake during and immediately after. These effects sometimes repeated during severe earthquakes; but great earthquakes, like Chile 1835, and giant earthquakes, like Chile 1960, are rare and remain completely unpredictable. This is one of the few areas of science, where experts remain largely in the dark. Darwin suggested that the effects were a result of ‘ …the rending of strata, at a point not very deep below the surface of the earth…' and ‘…when the crust yields to the tension, caused by its gradual elevation, there is a jar at the moment of rupture, and a greater movement...'. Darwin formulated big ideas about the earth evolution and its dynamics. These ideas set the tone for the tectonic plate theory to come. However, the plate tectonics does not completely explain why earthquakes occur within plates. Darwin emphasised that there are different kinds of earthquakes ‘...I confine the foregoing observations to the earthquakes on the coast of South America, or to similar ones, which seem generally to have been accompanied by elevation of the land. But, as we know that subsidence has gone on in other quarters of the world, fissures must there have been formed, and therefore earthquakes...' (we cite the Darwin's sentences following researchspace. auckland. ac. nz/handle/2292/4474). These thoughts agree with results of the last publications (see Nature 461, 870-872; 636-639 and 462, 42-43; 87-89). About 200 years ago Darwin gave oneself airs by the

  10. Relocation of Swarm Events in the June 1987 Earthquake Sequence from the Lake Aswan Area in Egypt

    NASA Astrophysics Data System (ADS)

    Hassoup, A.; Denton, P.; Maguire, P.; Hassib, G.

    We have examined the digital waveform data and relocated a number of events within the June 1987 earthquake swarm, which occurred beneath the northern part of Lake Aswan, 70 km southwest of the Aswan High Dam in Egypt. This swarm occurred between June 17th and 19th with a maximum magnitude event of ``ML''=3.5.Cross correlation between a chosen master and the analyzed events has been carried out on seismograms from stations of the Aswan network. The cross correlation demonstrates the presence of a difference in both the P wave (Δtp) and the S wave (Δts) arrival times at each station in the network relative to the arrival times of the master event at the same stations. Δtp ranges between -0.15 and 0.11 second, while Δts ranges between -0.17 and 0.11 second.The primary interpretation is that the se time differences represent an error in the manually picking arrival times. Then, Δtp and Δts values for each event result from a change in the hypocentral parameters from those of the master event, assuming the P- and S-wave velocity distribution remains constant during the swarm activity. This interpretation enables us to determine the relative distribution of hypocenters with respect to the hypocentral location of the master event. We present the results from a swarm of 9 events demonstrating they originate from a nearly unique location, rather than the zone identified from the preliminary locations which used manually picked onset times.

  11. Effects of gravel on infiltration, runoff, and sediment yield in landslide deposit slope in Wenchuan earthquake area, China.

    PubMed

    Li, Tianyang; He, Binghui; Chen, Zhanpeng; Zhang, Yi; Liang, Chuan; Wang, Renxin

    2016-06-01

    Amounts of landslide deposits were triggered by the Wenchuan earthquake with magnitude 8.0 on May 12, 2008. The landslide deposits were composed of soil and rock fragments, which play important roles in hydrological and erosion processes in the steep slope of landslide deposits. The mixtures of soil and gravels are common in the top layers of landslide deposits, and its processes are obviously different with the soil without gravels. Based on the data of field investigation, a series of simulated scouring flow experiments with four proportion of gravel (0, 25, 33.3, and 50 %) and three scouring flow rates (4, 8, 12 L/min) under two steep slopes (67.5, 72.7 %) were conducted sequentially to know the effects of proportion of gravel on infiltration capacity, runoff generation, and sediment production in the steep slope of landslide deposit. Results indicated that gravel had promoted or reduced effects on infiltration capacity which could affect further the cumulative runoff volume and cumulative sediment mass increase or decrease. The cumulative infiltration volume in 25 % proportion of gravel was less than those in 0, 33.3, and 50 % proportion of gravel. The cumulative runoff volume was in an order of 25 > 0 > 33.3 > 50 % while cumulative sediment mass ranked as 25 > 33.3 > 0 > 50 % with different proportions of gravel. A significant power relationship was found between scouring time and cumulative runoff volume as well as cumulative sediment mass. The relationship between average soil and water loss rate and proportion of gravel was able to express by quadratic function, with a high degree of reliability. The results have important implications for soil and water conservation and modeling in landslide deposit but also provide useful information for the similar conditions.

  12. Three Campaigns to Image the Earth's Interior Using Mermaids (Mobile Earthquake Recorder in Marine Areas by Indepen-dent Divers).

    NASA Astrophysics Data System (ADS)

    Pazmino, A.; Bonnieux, S.; Joubert, C.; Gonzales, N.; Hello, Y.; Nolet, G.

    2014-12-01

    Mermaids have been developed to improve seismic data coverage in the oceanic domain for imaging of the Earth's interior. Though housed in conventional Argo-type floats, hardware and software was developed to analyze acoustic signals and determine whether an earthquake has been recorded, and whether the Mermaid should to come up to the surface and transmit to the satellite. In contrast to the passive Argo floats, Mermaids are essentially floating computers that decide for themselves what to do. After testing in the Mediterranean and Indian Ocean and improving the concept for more than a year, we recently started two fully scientific experiments using Mermaids. In cooperation with Inocar, we deployed a fleet of 10 Mermaids in May 2014 around the Galapagos islands from the LAE Sirius to study the suspected mantle plume beneath these islands. We are interested in plumes because we do not understand very well how the mantle has retained an almost constant temperature for three or four billion years, an essential condition for life to develop. The depth of mantle plumes is an important unknown, because it may tell us how well the lower mantle is able to transmit heat into the upper mantle. A second experiment is taking place in the Ligurian Sea. This basin opened with a rifting phase in late Oligocene. The rifting phase of the Ligurian basin is followed by the Corsica - Sardinia block counterclockwise rotation, but the deeper causes of this are still poorly understood. Three Mermaids are deployed, and re-deployed after drifting too far west, to augment the P arrivals observed for 6 months with 5 OBS's during the 2008 Grosmarin campaign. The experience obtained with this first generation of Mermaids has led to the development of a new multidisciplinary float (Multimermaid), which is programmable, able to carry up to 8 sensors to a depth of 3000 m, and with a duration of at least five years.

  13. Gravity study through the Tualatin Mountains, Oregon: Understanding crustal structure and earthquake hazards in the Portland urban area

    USGS Publications Warehouse

    Blakely, R.J.; Beeson, M.H.; Cruikshank, K.; Wells, R.E.; Johnson, Aaron H.; Walsh, K.

    2004-01-01

    A high-resolution gravity survey through the Tualatin Mountains (Portland Nills) west of downtown Portland exhibits evidence of faults previously identified from surface geologic and aeromagnetic mapping. The gravity survey was conducted in 1996 along the 4.5-km length of a twin-bore tunnel, then under construction and now providing light-rail service between downtown Portland and communities west of the Portland Hills. Gravitational attraction gradually increases from west to east inside the tunnel, which reflects the tunnel's location between low-density sedimentary deposits of the Tualatin basin to the west and high-density, mostly concealed Eocene basalt to the east. Superimposed on this gradient are several steplike anomalies that we interpret as evidence for faulted contacts between rocks of contrasting density. The largest of these anomalies occurs beneath Sylvan Creek, where a fault had previously been mapped inside the tunnel. Another occurs 1200 m from the west portal, at the approximate intersection of the tunnel with an aeromagnetic anomaly associated with the Sylvan fault (formerly called the Oatfield fault). Lithologic cross sections based on these gravity data show that the steplike anomalies are consistent with steeply dipping reverse faults, although strike-slip displacements also may be important. Three gravity lows correspond with topographic lows directly overhead and may reflect zones of shearing. Several moderate earthquakes (M ??? 3.5) occurred near the present-day location of the tunnel in 1991, suggesting that some of these faults or other faults in the Portland Hills fault zone are seismically active.

  14. Effects of gravel on infiltration, runoff, and sediment yield in landslide deposit slope in Wenchuan earthquake area, China.

    PubMed

    Li, Tianyang; He, Binghui; Chen, Zhanpeng; Zhang, Yi; Liang, Chuan; Wang, Renxin

    2016-06-01

    Amounts of landslide deposits were triggered by the Wenchuan earthquake with magnitude 8.0 on May 12, 2008. The landslide deposits were composed of soil and rock fragments, which play important roles in hydrological and erosion processes in the steep slope of landslide deposits. The mixtures of soil and gravels are common in the top layers of landslide deposits, and its processes are obviously different with the soil without gravels. Based on the data of field investigation, a series of simulated scouring flow experiments with four proportion of gravel (0, 25, 33.3, and 50 %) and three scouring flow rates (4, 8, 12 L/min) under two steep slopes (67.5, 72.7 %) were conducted sequentially to know the effects of proportion of gravel on infiltration capacity, runoff generation, and sediment production in the steep slope of landslide deposit. Results indicated that gravel had promoted or reduced effects on infiltration capacity which could affect further the cumulative runoff volume and cumulative sediment mass increase or decrease. The cumulative infiltration volume in 25 % proportion of gravel was less than those in 0, 33.3, and 50 % proportion of gravel. The cumulative runoff volume was in an order of 25 > 0 > 33.3 > 50 % while cumulative sediment mass ranked as 25 > 33.3 > 0 > 50 % with different proportions of gravel. A significant power relationship was found between scouring time and cumulative runoff volume as well as cumulative sediment mass. The relationship between average soil and water loss rate and proportion of gravel was able to express by quadratic function, with a high degree of reliability. The results have important implications for soil and water conservation and modeling in landslide deposit but also provide useful information for the similar conditions. PMID:26965277

  15. Recent earthquakes in northern New York

    SciTech Connect

    Revetta, F.A.; Bockus, C.; O'Brian, B. . Dept. of Geology)

    1993-03-01

    The Massena, New York area located along the St. Lawrence River in northern New York has been the site of significant earthquake activity including the largest earthquake in New York (m = 6.0) on September 5, 1944. Historic earthquake data indicates the Cornwall-Massena area is a region of relatively high seismic activity, and the earthquake activity has been persistent for over a 400 year period. During the past year eleven small earthquakes have been recorded by the Potsdam Seismic Network in northern New York. Four of these earthquakes had epicenters located in the Massena-Cornwall area. One epicenter was located along the Carthage-Colton Mylonite Zone and one epicenter was located n the epicentral region of the October 7, 1984 Goodnow earthquake. Five earthquakes had epicenters located in Ontario and Quebec. These earthquake epicenters lie in a belt of seismicity that extends north-westerly from the northern Adirondacks into the Canadian Shield of western Quebec. Several explanations that have been presented to explain these earthquakes are (1) mafic intrusions (2) unmapped northwest trending faults (3) extension of the New England seamount chain and (4) crustal fractures due to the area passing over a hotspot. Four earthquakes in the Massena area lie very near extensions of the Gloucester and Winchester Spring faults into New York and may be related to the faults. Focal mechanism solutions of two earthquakes indicate thrusting along NW striking fault planes. Another possibility is the earthquakes are related to the Carthage-Colton Mylonite Zone. One earthquake is within four kms of the CCMZ and if the zone is extended northward beneath the lower Paleozoics, it passes through the epicenters on the Cornwall-Massena area.

  16. Pediatric Epidemic of Salmonella enterica Serovar Typhimurium in the Area of L’Aquila, Italy, Four Years after a Catastrophic Earthquake

    PubMed Central

    Nigro, Giovanni; Bottone, Gabriella; Maiorani, Daniela; Trombatore, Fabiana; Falasca, Silvana; Bruno, Gianfranco

    2016-01-01

    Background: A Salmonella enterica epidemic occurred in children of the area of L’Aquila (Central Italy, Abruzzo region) between June 2013 and October 2014, four years after the catastrophic earthquake of 6 April 2009. Methods: Clinical and laboratory data were collected from hospitalized and ambulatory children. Routine investigations for Salmonella infection were carried out on numerous alimentary matrices of animal origin and sampling sources for drinking water of the L’Aquila district, including pickup points of the two main aqueducts. Results: Salmonella infection occurred in 155 children (83 females: 53%), aged 1 to 15 years (mean 2.10). Of these, 44 children (28.4%) were hospitalized because of severe dehydration, electrolyte abnormalities, and fever resistant to oral antipyretic and antibiotic drugs. Three children (1.9%) were reinfected within four months after primary infection by the same Salmonella strain. Four children (2.6%), aged one to two years, were coinfected by rotavirus. A seven-year old child had a concomitant right hip joint arthritis. The isolated strains, as confirmed in about the half of cases or probable/possible in the remaining ones, were identified as S. enterica serovar Typhimurium [4,5:i:-], monophasic variant. Aterno river, bordering the L’Aquila district, was recognized as the main responsible source for the contamination of local crops and vegetables derived from polluted crops. Conclusions: The high rate of hospitalized children underlines the emergence of a highly pathogenic S. enterica strain probably subsequent to the contamination of the spring water sources after geological changes occurred during the catastrophic earthquake. PMID:27164121

  17. Earthquake Analysis.

    ERIC Educational Resources Information Center

    Espinoza, Fernando

    2000-01-01

    Indicates the importance of the development of students' measurement and estimation skills. Analyzes earthquake data recorded at seismograph stations and explains how to read and modify the graphs. Presents an activity for student evaluation. (YDS)

  18. Earthquake watch

    USGS Publications Warehouse

    Hill, M.

    1976-01-01

     When the time comes that earthquakes can be predicted accurately, what shall we do with the knowledge? This was the theme of a November 1975 conference on earthquake warning and response held in San Francisco called by Assistant Secretary of the Interior Jack W. Carlson. Invited were officials of State and local governments from Alaska, California, Hawaii, Idaho, Montana, Nevada, utah, Washington, and Wyoming and representatives of the news media. 

  19. Headaches prior to earthquakes

    NASA Astrophysics Data System (ADS)

    Morton, L. L.

    1988-06-01

    In two surveys of headaches it was noted that their incidence had increased significantly within 48 h prior to earthquakes from an incidence of 17% to 58% in the first survey using correlated samples and from 20.4% to 44% in the second survey using independent samples. It is suggested that an increase in positive air ions from rock compression may trigger head pain via a decrease in brain levels of the neurotransmitter serotonin. The findings are presented as preliminary, with the hope of generating further research efforts in areas more prone to earthquakes.

  20. Refinement Method for Residential Area Revision Using Remote Sensing Image and GIS Data in Earthquake Risk Assessment

    NASA Astrophysics Data System (ADS)

    Dou, A. X.; Yuan, X. X.; Wang, X. Q.; Li, Z. M.

    2016-06-01

    This paper proposes an automatic approach for residential areas revision by means of analysing the correlation between the residential area and the topographic and geographical factors. The approach consists of four major steps: the extracting of missing residential area from the remote sensing images with high resolution; the statistic analysing on the size changes of missing residential area in each grade of the elevation, slope, distance from the road and other impact factors; modelling of residential area modification in the urban and rural region; testing the methods using 100 counties data which are located in the middle part of China North-South Seismic Belt and comparing the result to the Land Use in map scale 1:100000. The experimental results present the accuracy of urban residents by 70% increased to 89.4%, rural residents by 47% up to 81.9%, rural residents from 8% increased to 78.5%. Therefore, there is available risk exposure information in a sparsely populated area because the spatial grid distributions of population and buildings are based on the residential areas. The proposed approach in this paper will improve the accuracy of the seismic risk assessment if it is applied to the national or the whole world.

  1. Seismic velocity structure in the Hemet Stepover and Trifurcation Areas of the San Jacinto Fault Zone from double-difference earthquake tomography

    NASA Astrophysics Data System (ADS)

    Allam, A. A.; Ben-Zion, Y.; Vernon, F.; Kurzon, I.

    2013-12-01

    We present tomographic images of crustal velocity structures in the Hemet Stepover and Trifurcation areas of the San Jacinto Fault Zone (SJFZ) based on double-difference inversions of earthquake arrival times. We discretize both regions with a horizontal 250m grid spacing and a vertical 500m spacing within 50km by 50km by 20km volumes. We invert for VP, VS, and hypocenter location using data from 16064 earthquakes recorded at 136 stations. In total, we use 266,969 P and 148,249 S arrivals to constrain the seismic velocity structures in the two regions. With large numbers of both arrivals, we are able to obtain images of VP and VS at similar resolutions, enabling us to make spatial maps of and interpret the VP/VS ratios. Though ray coverage is limited at shallow depths, we obtain high-fidelity images of seismic velocities from 2 to 12 km, and validate the results using checkerboard tests. The tomographic images indicate that the velocity of the trifurcation area as a whole is lower than adjacent unfaulted material. We interpret a 4km-wide low velocity zone in the trifurcation itself as fault zone damage related due to high VP/VS ratio. We also observe clear velocity contrasts across the Buck Ridge, Clark, and Coyote Creek segments of the SJFZ. The Anza segment of the SJFZ, to the NW of the trifurcation area, displays a strong (up to 27%) contrast of VS from 2km to 9km. In the Hemet Stepover, a low velocity zone between the Claremont and Casa Loma Strands narrows with depth, with clear velocity contrasts observed across both segments. A roughly 10km-wide zone of low velocity and low VP/VS ratio at the NW tip of the Hot Springs fault is indicative of either unconsolidated sediments associated with the San Jacinto basin, or fluid-filled cracks within a broad deformation zone. Relocated seismicity tends to align with the surface traces of the various fault strands, though it is offset to the northeast of the Casa Loma-Clark strand and to the southwest of the Hot Springs

  2. Earthquakes for Kids

    MedlinePlus

    ... Hazards Data & Products Learn Monitoring Research Earthquakes for Kids Kid's Privacy Policy Earthquake Topics for Education FAQ Earthquake Glossary For Kids Prepare Google Earth/KML Files Earthquake Summary Posters ...

  3. Outbreak of Culex inatomii in disaster areas of the Great East Japan earthquake and tsunami in 2011, with ecological notes on their larval habitats, biting behavior, and reproduction.

    PubMed

    Tsuda, Yoshio; Kim, Kyeong Soon

    2013-03-01

    Outbreaks of Culex inatomii occurred widely in disaster areas of the tsunami caused by the Great East Japan earthquake in March 2011. Mosquitoes were collected in southern Miyagi Prefecture and northern Fukushima Prefecture in August and September 2011, respectively. In southern Miyagi Prefecture, the average number of adult Cx. inatomii collected by a suction trap baited with 1 kg of dry ice ranged between 69.3 and 132.8 per day in locations within 2.6 km from the coast in tsunami areas, while no Cx. inatomii individuals were collected 8.3 km from the coast, where seawater did not reach, and which therefore escaped the tsunami disaster. There were many ground pools of brackish water of various sizes, and larvae of Cx. inatomii were collected in 48% and 36% of the pools examined in Miyagi Prefecture and Fukushima Prefecture, respectively. Ecological notes on the larval habitats, biting behavior, seasonal prevalence, and reproduction of Cx. inatomii are presented for reference based on ecological studies conducted in Sakata Wetland, Niigata Prefecture, central Japan, in June and August 2011. Ecological factors relating to the current outbreak and the potential medical importance of Cx. inatomii are discussed.

  4. Collating and Curating Neuroanatomical Nomenclatures: Principles and Use of the Brain Architecture Knowledge Management System (BAMS)

    PubMed Central

    Bota, Mihail; Swanson, Larry W.

    2009-01-01

    Terms used to describe nervous system parts and their interconnections are rife with synonyms, partial correspondences, and even homonyms, making effective scientific communication unnecessarily difficult. To address this problem a new Topological Relations schema for the Relations module of BAMS (Brain Architecture Knowledge Management System) was created. It includes a representation of the qualitative spatial relations between nervous system parts defined in different neuroanatomical nomenclatures or atlases and is general enough to record data and metadata from the literature, regardless of description level or species. Based on this foundation a Projections Translations inference engine was developed for the BAMS interface that automatically translates neuroanatomical projection (axonal inputs and outputs) reports across nomenclatures from translated information. To make BAMS more useful to the neuroscience community three things were done. First, we implemented a simple schema for validation of the translated neuroanatomical projections. Second, more than 1,000 topological relations between brain gray matter regions for the rat were inserted, along with associated details. Finally, a case study was performed to enter all historical or legacy published information about terminology related to one relatively complex gray matter region of the rat. The bed nuclei of the stria terminalis (BST) were chosen and 21 different nomenclatures from 1923 to present were collated, along with 284 terms for parts (gray matter differentiations), 360 qualitative topological relations between parts, and more than 7,000 details about spatial relations between parts, all of which was annotated with appropriate metadata. This information was used to construct a graphical “knowledge map” of relations used in the literature to describe subdivisions of the rat BST. PMID:20407640

  5. A comprehensive analysis of earthquake damage patterns using high dimensional model representation feature selection

    NASA Astrophysics Data System (ADS)

    Taşkin Kaya, Gülşen

    2013-10-01

    Recently, earthquake damage assessment using satellite images has been a very popular ongoing research direction. Especially with the availability of very high resolution (VHR) satellite images, a quite detailed damage map based on building scale has been produced, and various studies have also been conducted in the literature. As the spatial resolution of satellite images increases, distinguishability of damage patterns becomes more cruel especially in case of using only the spectral information during classification. In order to overcome this difficulty, textural information needs to be involved to the classification to improve the visual quality and reliability of damage map. There are many kinds of textural information which can be derived from VHR satellite images depending on the algorithm used. However, extraction of textural information and evaluation of them have been generally a time consuming process especially for the large areas affected from the earthquake due to the size of VHR image. Therefore, in order to provide a quick damage map, the most useful features describing damage patterns needs to be known in advance as well as the redundant features. In this study, a very high resolution satellite image after Iran, Bam earthquake was used to identify the earthquake damage. Not only the spectral information, textural information was also used during the classification. For textural information, second order Haralick features were extracted from the panchromatic image for the area of interest using gray level co-occurrence matrix with different size of windows and directions. In addition to using spatial features in classification, the most useful features representing the damage characteristic were selected with a novel feature selection method based on high dimensional model representation (HDMR) giving sensitivity of each feature during classification. The method called HDMR was recently proposed as an efficient tool to capture the input

  6. Earthquake Scaling, Simulation and Forecasting

    NASA Astrophysics Data System (ADS)

    Sachs, Michael Karl

    Earthquakes are among the most devastating natural events faced by society. In 2011, just two events, the magnitude 6.3 earthquake in Christcurch New Zealand on February 22, and the magnitude 9.0 Tohoku earthquake off the coast of Japan on March 11, caused a combined total of $226 billion in economic losses. Over the last decade, 791,721 deaths were caused by earthquakes. Yet, despite their impact, our ability to accurately predict when earthquakes will occur is limited. This is due, in large part, to the fact that the fault systems that produce earthquakes are non-linear. The result being that very small differences in the systems now result in very big differences in the future, making forecasting difficult. In spite of this, there are patterns that exist in earthquake data. These patterns are often in the form of frequency-magnitude scaling relations that relate the number of smaller events observed to the number of larger events observed. In many cases these scaling relations show consistent behavior over a wide range of scales. This consistency forms the basis of most forecasting techniques. However, the utility of these scaling relations is limited by the size of the earthquake catalogs which, especially in the case of large events, are fairly small and limited to a few 100 years of events. In this dissertation I discuss three areas of earthquake science. The first is an overview of scaling behavior in a variety of complex systems, both models and natural systems. The focus of this area is to understand how this scaling behavior breaks down. The second is a description of the development and testing of an earthquake simulator called Virtual California designed to extend the observed catalog of earthquakes in California. This simulator uses novel techniques borrowed from statistical physics to enable the modeling of large fault systems over long periods of time. The third is an evaluation of existing earthquake forecasts, which focuses on the Regional

  7. High codimensional bifurcation analysis to a six-neuron BAM neural network.

    PubMed

    Liu, Yanwei; Li, Shanshan; Liu, Zengrong; Wang, Ruiqi

    2016-04-01

    In this article, the high codimension bifurcations of a six-neuron BAM neural network system with multiple delays are addressed. We first deduce the existence conditions under which the origin of the system is a Bogdanov-Takens singularity with multiplicities two or three. By choosing the connection coefficients as bifurcation parameters and using the formula derived from the normal form theory and the center manifold, the normal forms of Bogdanov-Takens and triple zero bifurcations are presented. Some numerical examples are shown to support our main results.

  8. Estimation of Future Earthquake Losses in California

    NASA Astrophysics Data System (ADS)

    Rowshandel, B.; Wills, C. J.; Cao, T.; Reichle, M.; Branum, D.

    2003-12-01

    Recent developments in earthquake hazards and damage modeling, computing, and data management and processing, have made it possible to develop estimates of the levels of damage from earthquakes that may be expected in the future in California. These developments have been mostly published in the open literature, and provide an opportunity to estimate the levels of earthquake damage Californians can expect to suffer during the next several decades. Within the past 30 years, earthquake losses have increased dramatically, mostly because our exposure to earthquake hazards has increased. All but four of the recent damaging earthquakes have occurred distant from California's major population centers. Two, the Loma Prieta earthquake and the San Fernando earthquake, occurred on the edges of major populated areas. Loma Prieta caused significant damage in the nearby Santa Cruz and in the more distant, heavily populated, San Francisco Bay area. The 1971 San Fernando earthquake had an epicenter in the lightly populated San Gabriel Mountains, but caused slightly over 2 billion dollars in damage in the Los Angeles area. As urban areas continue to expand, the population and infrastructure at risk increases. When earthquakes occur closer to populated areas, damage is more significant. The relatively minor Whittier Narrows earthquake of 1987 caused over 500 million dollars in damage because it occurred in the Los Angeles metropolitan area, not at its fringes. The Northridge earthquake had fault rupture directly beneath the San Fernando Valley, and caused about 46 billion dollars in damage. This vast increase in damage from the San Fernando earthquake reflected both the location of the earthquake directly beneath the populated area and the 23 years of continued development and resulting greater exposure to potential damage. We have calculated losses from potential future earthquake, both as scenarios of potential earthquakes and as annualized losses considering all the potential

  9. Liquefaction susceptibility assessment in fluvial plains using airborne lidar: the case of the 2012 Emilia earthquake sequence area (Italy)

    NASA Astrophysics Data System (ADS)

    Civico, R.; Brunori, C. A.; De Martini, P. M.; Pucci, S.; Cinti, F. R.; Pantosti, D.

    2015-11-01

    We report a case study from the Po River plain region (northern Italy), where significant liquefaction-related land and property damage occurred during the 2012 Emilia seismic sequence. We took advantage of a 1 m pixel lidar digital terrain model (DTM) and of the 2012 Emilia coseismic liquefaction data set to (a) perform a detailed geomorphological study of the Po River plain area and (b) quantitatively define the liquefaction susceptibility of the geomorphologic features that experienced different abundance of liquefaction. One main finding is that linear topographic highs of fluvial origin - together with crevasse splays, abandoned riverbeds and very young land reclamation areas - acted as a preferential location for the occurrence of liquefaction phenomena. Moreover, we quantitatively defined a hierarchy in terms of liquefaction susceptibility for an ideal fluvial environment. We observed that a very high liquefaction susceptibility is found in coincidence with fluvial landforms, a high-to-moderate liquefaction susceptibility within a buffer distance of 100 and 200 m from mapped fluvial landforms and a low liquefaction susceptibility outside fluvial landforms and relative buffer areas. Lidar data allowed a significant improvement in mapping with respect to conventionally available topographic data and/or aerial imagery. These results have significant implications for accurate hazard and risk assessment as well as for land-use planning. We propose a simple geomorphological approach for liquefaction susceptibility estimation. Our findings can be applied to areas beyond Emilia that are characterized by similar fluvial-dominated environments and prone to significant seismic hazard.

  10. Major Earthquakes of the Past Decade (2000-2010): A Comparative Review of Various Aspects of Management

    PubMed Central

    Kalantar Motamedi, Mohammad Hosein; Sagafinia, Masoud; Ebrahimi, Ali; Shams, Ehsan; Kalantar Motamedi, Mostafa

    2012-01-01

    Objectives: This article sought to review and compare data of major earthquakes of the past decade and their aftermath in order to compare the magnitude, death toll, type of injuries, management procedures, extent of destruction and effectiveness of relief efforts. Materials and Methods: A retrospective study of the various aspects of management and aftermath of 5 major earthquakes of the past decade (2000–2010) was undertaken. This included earthquakes occurring in Bam Iran, Sichuan China, Port-au-Prince Haiti, Kashmir Pakistan and Ica Peru. A literature search was done via computer of published articles (indexed in Pubmed). The issues assessed included: 1)Local magnitude,2)Type of building structure 3)Time of the earthquake (day/time/season), 4)Time to rescue, 5)Triage, Transfer, and Treatment 6) Distribution of casualties (dead/ injured), 7)Degree of city damage, 8)Degree of damage to health facilities, 9)Field hospital availability, 10)International aid, 11)Air transfer, 12) Telecommunication systems availability, 13) PTSD prevalence, 14) Most common injury and 15) Most common disease outbreak. Results: The Bam earthquake had the lowest (6.6 Richter’s) and the Sichuan earthquake had the greatest magnitude (8.0 Richter’s). Mortality in Haiti was 212,000 and it was the deadliest earthquake of the past decade. Collapse of heavy clay roofing structures was a major cause of death in Iran and Pakistan. Earthquakes occurring at night and nonworking days carried a high death toll. The time to rescue and treat was the lengthiest in Haiti (possibly contributing to the death to injured ratio). However, the worst dead to injured ratios were in Bam (51%) and in Pakistan (47%); the best ratio was in China (15%). Iran and Pakistan suffered the highest percentage of damage to the health facilities (90%). Field hospital availability, international aid and air transfer were important issues. Telecommunication systems were best in China and worst in Pakistan. PTSD

  11. Interpretation of earthquake-induced landslides triggered by the 12 May 2008, M7.9 Wenchuan earthquake in the Beichuan area, Sichuan Province, China using satellite imagery and Google Earth

    USGS Publications Warehouse

    Sato, H.P.; Harp, E.L.

    2009-01-01

    The 12 May 2008 M7.9 Wenchuan earthquake in the People's Republic of China represented a unique opportunity for the international community to use commonly available GIS (Geographic Information System) tools, like Google Earth (GE), to rapidly evaluate and assess landslide hazards triggered by the destructive earthquake and its aftershocks. In order to map earthquake-triggered landslides, we provide details on the applicability and limitations of publicly available 3-day-post- and pre-earthquake imagery provided by GE from the FORMOSAT-2 (formerly ROCSAT-2; Republic of China Satellite 2). We interpreted landslides on the 8-m-resolution FORMOSAT-2 image by GE; as a result, 257 large landslides were mapped with the highest concentration along the Beichuan fault. An estimated density of 0.3 landslides/km2 represents a minimum bound on density given the resolution of available imagery; higher resolution data would have identified more landslides. This is a preliminary study, and further study is needed to understand the landslide characteristics in detail. Although it is best to obtain landslide locations and measurements from satellite imagery having high resolution, it was found that GE is an effective and rapid reconnaissance tool. ?? 2009 Springer-Verlag.

  12. 3D P-Wave Velocity Structure of the Crust and Relocation of Earthquakes in 21 the Lushan Source Area

    NASA Astrophysics Data System (ADS)

    Yu, X.; Wang, X.; Zhang, W.

    2014-12-01

    The double difference seismic tomography method is applied to the absolute first arrival P wave arrival times and high quality relative P arrival times of the Lushan seismic sequence to determine the detailed crustal 3D P wave velocity structure and the hypocenter parameters in the Lushan seismic area. The results show that the Lushan mainshock locates at 30.28 N, 103.98 E, with the depth of 16.38 km. The leading edge of aftershock in the northeast of mainshock present a spade with a steep dip angle, the aftershocks' extended length is about 12 km. In the southwest of the Lushan mainshock, the leading edge of aftershock in low velocity zone slope gently, the aftershocks' extended length is about 23 km. The P wave velocity structure of the Lushan seismic area shows obviously lateral heterogeneity. The P wave velocity anomalies represent close relationship with topographic relief and geological structure. In Baoxing area the complex rocks correspond obvious high-velocity anomalies extending down to 15 km depth,while the Cenozoic rocks are correlated with low-velocity anomalies. Our high-resolution tomographic model not only displays the general features contained in the previous models, but also reveals some new features. An obvious high-velocity anomaly is visible in Daxing area. The high-velocity anomalies beneath Baoxing and Daxing connect each other in 10 km depth, which makes the contrast between high and low velocity anomalies more sharp. Above 20 km depth the velocity structure in southwest and northeast segment of the mainshock shows a big difference: low-velocity anomalies are dominated the southwest segment, while high-velocity anomalies rule the northeast segment. The Lushan mainshock locates at the leading edge of a low-velocity anomaly surrounded by the Baoxing and Daxing high-velocity anomalies. The Lushan aftershocks in southwest are distributed in low-velocity anomalies or the transition belt: the footwall represents low-velocity anomalies, while

  13. Earthquake damage to transportation systems

    USGS Publications Warehouse

    McCullough, Heather

    1994-01-01

    Earthquakes represent one of the most destructive natural hazards known to man. A large magnitude earthquake near a populated area can affect residents over thousands of square kilometers and cause billions of dollars in property damage. Such an event can kill or injure thousands of residents and disrupt the socioeconomic environment for months, sometimes years. A serious result of a large-magnitude earthquake is the disruption of transportation systems, which limits post-disaster emergency response. Movement of emergency vehicles, such as police cars, fire trucks and ambulances, is often severely restricted. Damage to transportation systems is categorized below by cause including: ground failure, faulting, vibration damage, and tsunamis.

  14. Earthquakes, November-December 1977

    USGS Publications Warehouse

    Person, W.J.

    1978-01-01

    In the United States, the largest earthquake during this reporting period was a magntidue 6.6 in the Andreanof Islands, which are part of the Aleutian Islands chain, on November 4 that caused some minor damage. Northern California was struck by a magnitude 4.8 earthquake on November 22 causing moderate damage in the Willits area. This was the most damaging quake in the United States during the year. Two major earthquakes of magntidues 7.0 or above to 14 for the year. 

  15. External effective radiation dose to workers in the restricted area of the Fukushima Daiichi Nuclear Power Plant during the third year after the Great East Japan Earthquake.

    PubMed

    Sakumi, Akira; Miyagawa, Ryu; Tamari, Yuki; Nawa, Kanabu; Sakura, Osamu; Nakagawa, Keiichi

    2016-03-01

    Since the Great East Japan Earthquake on 11 March 2011, Iitate Village has continued to be classified as a deliberate evacuation area, in which residents are estimated to receive an annual additional effective radiation dose of >20 mSv. Some companies still operate in Iitate Village, with a special permit from the Cabinet Office Team in Charge of Assisting the Lives of Disaster Victims. In this study, we measured the annual effective radiation dose to workers in Iitate Village from 15 January to 13 December 2013. The workers stayed in Iitate for 10 h and left the village for the remaining 14 h each working day. They worked for 5 days each week in Iitate Village, but stayed outside of the village for the remaining 2 days each week. We found that the effective radiation dose of 70% of the workers was <2 mSv, including natural radiation; the maximum dose was 3.6 mSv. We estimated the potential annual additional effective radiation dose if people returned full-time to Iitate. Our analysis supports the plan for people to return to their home village at the end of 2017.

  16. External effective radiation dose to workers in the restricted area of the Fukushima Daiichi Nuclear Power Plant during the third year after the Great East Japan Earthquake

    PubMed Central

    Sakumi, Akira; Miyagawa, Ryu; Tamari, Yuki; Nawa, Kanabu; Sakura, Osamu; Nakagawa, Keiichi

    2016-01-01

    Since the Great East Japan Earthquake on 11 March 2011, Iitate Village has continued to be classified as a deliberate evacuation area, in which residents are estimated to receive an annual additional effective radiation dose of >20 mSv. Some companies still operate in Iitate Village, with a special permit from the Cabinet Office Team in Charge of Assisting the Lives of Disaster Victims. In this study, we measured the annual effective radiation dose to workers in Iitate Village from 15 January to 13 December 2013. The workers stayed in Iitate for 10 h and left the village for the remaining 14 h each working day. They worked for 5 days each week in Iitate Village, but stayed outside of the village for the remaining 2 days each week. We found that the effective radiation dose of 70% of the workers was <2 mSv, including natural radiation; the maximum dose was 3.6 mSv. We estimated the potential annual additional effective radiation dose if people returned full-time to Iitate. Our analysis supports the plan for people to return to their home village at the end of 2017. PMID:26661855

  17. Earthquake Hazard Mitigation Strategy in Indonesia

    NASA Astrophysics Data System (ADS)

    Karnawati, D.; Anderson, R.; Pramumijoyo, S.

    2008-05-01

    Because of the active tectonic setting of the region, the risks of geological hazards inevitably increase in Indonesian Archipelagoes and other ASIAN countries. Encouraging community living in the vulnerable area to adapt with the nature of geology will be the most appropriate strategy for earthquake risk reduction. Updating the Earthquake Hazard Maps, enhancement ofthe existing landuse management , establishment of public education strategy and method, strengthening linkages among stake holders of disaster mitigation institutions as well as establishement of continues public consultation are the main strategic programs for community resilience in earthquake vulnerable areas. This paper highlights some important achievements of Earthquake Hazard Mitigation Programs in Indonesia, together with the difficulties in implementing such programs. Case examples of Yogyakarta and Bengkulu Earthquake Mitigation efforts will also be discussed as the lesson learned. The new approach for developing earthquake hazard map which is innitiating by mapping the psychological aspect of the people living in vulnerable area will be addressed as well.

  18. The CATDAT damaging earthquakes database

    NASA Astrophysics Data System (ADS)

    Daniell, J. E.; Khazai, B.; Wenzel, F.; Vervaeck, A.

    2011-08-01

    The global CATDAT damaging earthquakes and secondary effects (tsunami, fire, landslides, liquefaction and fault rupture) database was developed to validate, remove discrepancies, and expand greatly upon existing global databases; and to better understand the trends in vulnerability, exposure, and possible future impacts of such historic earthquakes. Lack of consistency and errors in other earthquake loss databases frequently cited and used in analyses was a major shortcoming in the view of the authors which needed to be improved upon. Over 17 000 sources of information have been utilised, primarily in the last few years, to present data from over 12 200 damaging earthquakes historically, with over 7000 earthquakes since 1900 examined and validated before insertion into the database. Each validated earthquake includes seismological information, building damage, ranges of social losses to account for varying sources (deaths, injuries, homeless, and affected), and economic losses (direct, indirect, aid, and insured). Globally, a slightly increasing trend in economic damage due to earthquakes is not consistent with the greatly increasing exposure. The 1923 Great Kanto (214 billion USD damage; 2011 HNDECI-adjusted dollars) compared to the 2011 Tohoku (>300 billion USD at time of writing), 2008 Sichuan and 1995 Kobe earthquakes show the increasing concern for economic loss in urban areas as the trend should be expected to increase. Many economic and social loss values not reported in existing databases have been collected. Historical GDP (Gross Domestic Product), exchange rate, wage information, population, HDI (Human Development Index), and insurance information have been collected globally to form comparisons. This catalogue is the largest known cross-checked global historic damaging earthquake database and should have far-reaching consequences for earthquake loss estimation, socio-economic analysis, and the global reinsurance field.

  19. Structural and magnetic properties of Ni-Zn doped BaM nanocomposite via citrate precursor

    NASA Astrophysics Data System (ADS)

    Rana, Kush; Thakur, Preeti; Tomar, Monika; Gupta, Vinay; Thakur, Atul

    2016-05-01

    Ni-Zn substituted M-type barium ferrite nanocomposite has been prepared via citrate precursor method. Nanocomposite having composition BaNi0.5Zn0.5Fe11O19 was sintered at 900°C for 3hrs and characterized by using different characterization techniques. X-ray diffraction (XRD) confirmed the formation of double phase with most prominent peak at (114). Average crystallite size for pure BaM and BNZFO were found to be 36 nm & 45 nm. Field emission scanning electron microscopy (FESEM) confirmed the formation of hexagonal platelets with a layered structure. Magnetic properties of these samples were investigated by using vibrating sample magnetometer (VSM). Magnetic parameters like saturation magnetization (Ms), coericivity (Hc) and squareness ratio (SQR) of nanocomposite were found to be 60 emu/g, 3663 Oe and 0.6163 respectively. These values were noticed to be higher as compared to pure BaM. Enhanced magnetic properties of nanocomposite were strongly dependent on exchange coupling. Therefore these properties make this nanocomposite a suitable candidate for magnetic recording and high frequency applications.

  20. StratBAM: A Discrete-Event Simulation Model to Support Strategic Hospital Bed Capacity Decisions.

    PubMed

    Devapriya, Priyantha; Strömblad, Christopher T B; Bailey, Matthew D; Frazier, Seth; Bulger, John; Kemberling, Sharon T; Wood, Kenneth E

    2015-10-01

    The ability to accurately measure and assess current and potential health care system capacities is an issue of local and national significance. Recent joint statements by the Institute of Medicine and the Agency for Healthcare Research and Quality have emphasized the need to apply industrial and systems engineering principles to improving health care quality and patient safety outcomes. To address this need, a decision support tool was developed for planning and budgeting of current and future bed capacity, and evaluating potential process improvement efforts. The Strategic Bed Analysis Model (StratBAM) is a discrete-event simulation model created after a thorough analysis of patient flow and data from Geisinger Health System's (GHS) electronic health records. Key inputs include: timing, quantity and category of patient arrivals and discharges; unit-level length of care; patient paths; and projected patient volume and length of stay. Key outputs include: admission wait time by arrival source and receiving unit, and occupancy rates. Electronic health records were used to estimate parameters for probability distributions and to build empirical distributions for unit-level length of care and for patient paths. Validation of the simulation model against GHS operational data confirmed its ability to model real-world data consistently and accurately. StratBAM was successfully used to evaluate the system impact of forecasted patient volumes and length of stay in terms of patient wait times, occupancy rates, and cost. The model is generalizable and can be appropriately scaled for larger and smaller health care settings. PMID:26310949

  1. StratBAM: A Discrete-Event Simulation Model to Support Strategic Hospital Bed Capacity Decisions.

    PubMed

    Devapriya, Priyantha; Strömblad, Christopher T B; Bailey, Matthew D; Frazier, Seth; Bulger, John; Kemberling, Sharon T; Wood, Kenneth E

    2015-10-01

    The ability to accurately measure and assess current and potential health care system capacities is an issue of local and national significance. Recent joint statements by the Institute of Medicine and the Agency for Healthcare Research and Quality have emphasized the need to apply industrial and systems engineering principles to improving health care quality and patient safety outcomes. To address this need, a decision support tool was developed for planning and budgeting of current and future bed capacity, and evaluating potential process improvement efforts. The Strategic Bed Analysis Model (StratBAM) is a discrete-event simulation model created after a thorough analysis of patient flow and data from Geisinger Health System's (GHS) electronic health records. Key inputs include: timing, quantity and category of patient arrivals and discharges; unit-level length of care; patient paths; and projected patient volume and length of stay. Key outputs include: admission wait time by arrival source and receiving unit, and occupancy rates. Electronic health records were used to estimate parameters for probability distributions and to build empirical distributions for unit-level length of care and for patient paths. Validation of the simulation model against GHS operational data confirmed its ability to model real-world data consistently and accurately. StratBAM was successfully used to evaluate the system impact of forecasted patient volumes and length of stay in terms of patient wait times, occupancy rates, and cost. The model is generalizable and can be appropriately scaled for larger and smaller health care settings.

  2. Seismic wave propagation in the MELT Experiment area: Probing the nature of intraplate earthquakes, lithospheric anisotropy and mantle upwelling in the vicinity of the southern East Pacific Rise

    NASA Astrophysics Data System (ADS)

    Hung, Shu-Huei

    This thesis conducts comprehensive investigations of on-going tectonic processes from observations and modeling of seismic waves propagating through the MELT Experiment area across the southern East Pacific Rise (EPR). In Chapter One, a moment-tensor inversion procedure is developed to derive the source mechanism of a sequence of teleseismic earthquakes about 300 km west of the 18sp°S EPR. All the determined events are nearly pure normal faults striking in a variety of directions with significant non-double-couple components, which are likely due to simultaneously slip on randomly-oriented fault planes. The summed moment tensor indicates no preferred orientation of horizontal extension with maximum vertical compression, consistent with the release of thermal stresses in the cooling oceanic seafloor. In Chapter Two, a parallel multi-domain pseudospectral method is developed for simulation of seismic wave propagation in generalized inhomogeneous and anisotropic media. We illustrate the variabilities in wavefront geometry and waveform complexity for different anisotropic symmetries present in the Earth. In Chapter Three, we measure shear wave splitting parameters to constrain lithospheric anisotropy in the vicinity of the earthquake swarm. Most of the resolving fast polarization directions are subparallel to the plate motion vector, attributable to crystal fabrics formed by shearing mantle flow. Some of them are scattered nearly orthogonal to the spreading direction, associated with crack-induced crustal anisotropy. Waveform modeling is employed to test the hypothesis of double-layered anisotropy. The models reconstruct the observed splitting pattern and demonstrate that shear waves split in nonuniform anisotropic layers display frequency-dependent behavior. In Chapter Four, we combine observed and synthetic waveforms and travel-time delays recorded in the MELT seismometer array to characterize the nature of mantle upwelling beneath the EPR. The similar waveforms and

  3. 2010 Chile Earthquake Aftershock Response

    NASA Astrophysics Data System (ADS)

    Barientos, Sergio

    2010-05-01

    The Mw=8.8 earthquake off the coast of Chile on 27 February 2010 is the 5th largest megathrust earthquake ever to be recorded and provides an unprecedented opportunity to advance our understanding of megathrust earthquakes and associated phenomena. The 2010 Chile earthquake ruptured the Concepcion-Constitucion segment of the Nazca/South America plate boundary, south of the Central Chile region and triggered a tsunami along the coast. Following the 2010 earthquake, a very energetic aftershock sequence is being observed in an area that is 600 km along strike from Valparaiso to 150 km south of Concepcion. Within the first three weeks there were over 260 aftershocks with magnitude 5.0 or greater and 18 with magnitude 6.0 or greater (NEIC, USGS). The Concepcion-Constitucion segment lies immediately north of the rupture zone associated with the great magnitude 9.5 Chile earthquake, and south of the 1906 and the 1985 Valparaiso earthquakes. The last great subduction earthquake in the region dates back to the February 1835 event described by Darwin (1871). Since 1835, part of the region was affected in the north by the Talca earthquake in December 1928, interpreted as a shallow dipping thrust event, and by the Chillan earthquake (Mw 7.9, January 1939), a slab-pull intermediate depth earthquake. For the last 30 years, geodetic studies in this area were consistent with a fully coupled elastic loading of the subduction interface at depth; this led to identify the area as a mature seismic gap with potential for an earthquake of magnitude of the order 8.5 or several earthquakes of lesser magnitude. What was less expected was the partial rupturing of the 1985 segment toward north. Today, the 2010 earthquake raises some disturbing questions: Why and how the rupture terminated where it did at the northern end? How did the 2010 earthquake load the adjacent segment to the north and did the 1985 earthquake only partially ruptured the plate interface leaving loaded asperities since

  4. Application of Rapid Earthquake Location for Earthquake Early Warning in Korea

    NASA Astrophysics Data System (ADS)

    Kim, K.; Rydelek, P. A.; Suk, B.

    2008-12-01

    Economic growth, industrialization and urbanization have made society more vulnerable then ever to seismic hazard in Korea. Although Korea has not experienced severe damage due to earthquakes during the last few decades, there is little doubt of the potential for large earthquakes in Korea as documented in the historical literature. As we see no immediate promise of short-term earthquake prediction with current science and technology, earthquake early warning systems attract more and more attention as a practical measure to mitigate damage from earthquakes. Earthquake early warning systems provide a few seconds to tens of seconds of warning time before the onset of strong ground shaking. To achieve rapid earthquake location, we propose to take full advantage of information from existing seismic networks; by using P wave arrival times at two nearest stations from the earthquake hypocenter and also information that P waves have not yet arrived at other stations. Ten earthquakes in the Korean peninsula and its vicinity are selected for the feasibility study. We observed that location results are not reliable when earthquakes occur outside of the seismic network. Earthquakes inside the seismic network, however, can be located very rapidly for the purpose of earthquake early warning. Seoul metropolitan area may secure 10 - 50 seconds of warning time before any strong shaking starts for certain events. Carefully orchestrated actions during the given warning time should be able to reduce hazard and mitigate damages due to potentially disastrous earthquakes.

  5. MitoBamAnnotator: A web-based tool for detecting and annotating heteroplasmy in human mitochondrial DNA sequences.

    PubMed

    Zhidkov, Ilia; Nagar, Tal; Mishmar, Dan; Rubin, Eitan

    2011-11-01

    The use of Next-Generation Sequencing of mitochondrial DNA is becoming widespread in biological and clinical research. This, in turn, creates a need for a convenient tool that detects and analyzes heteroplasmy. Here we present MitoBamAnnotator, a user friendly web-based tool that allows maximum flexibility and control in heteroplasmy research. MitoBamAnnotator provides the user with a comprehensively annotated overview of mitochondrial genetic variation, allowing for an in-depth analysis with no prior knowledge in programming.

  6. Changes in the frequency and clinical features of suicide attempts in the midwestern area of Kanagawa after the great East Japan earthquake.

    PubMed

    Kato, Koji; Mikami, Katsunaka; Kimoto, Keitaro; Kimoto, Kousuke; Takahashi, Yuki; Sato, Reiko; Matsumoto, Hideo

    2014-03-01

    The aim of this study was to investigate the relationship between the clinical features of suicide attempts and the Great East Japan earthquake in Kanagawa. We enrolled 592 patients who attempted suicide and were hospitalized for inpatient treatment. Clinical features were compared between before the earthquake (A) and after the earthquake (B) groups. The number of suicide attempts increased from 286 to 306. The rate of increase in suicide attempts in men was the highest in the age group of 40-59 years. The frequency of joblessness, family psychiatric histories, precipitating event, and alcohol intake at suicide attempt was significantly higher in the B group than in the A group. The number of patients in serious condition in the B group was significantly higher than that in the A group. Other clinical features related to suicide in people who were indirectly affected by the earthquake disaster should be investigated to develop targeted prevention strategies.

  7. Oceanic Sub-Moho Reflectors in and Around the Segmentation Boundary Between the Tonankai-Nankai Earthquake Area, the Central Nankai Trough

    NASA Astrophysics Data System (ADS)

    Nakanishi, A.; Kodaira, S.; Miura, S.; Ito, A.; Sato, T.; Park, J.; Obana, K.; Kaneda, Y.

    2006-12-01

    The Nankai Trough is a unique subduction zone because the recurrence intervals of M8 class earthquakes and the segmentation of rupture zones are well documented on the basis of geophysical, geological and historic data. In 2004, large intraslab earthquake (Mw7.5) occurred southeast off the Kii Peninsula, the central Nankai Trough. Recent ocean bottom seismograph observation off the Kii Peninsula shows seismicity concentrated in the oceanic crust and the uppermost mantle. To understand the genesis of such intraslab earthquakes and its relation to large interplate earthquakes as well as to obtain an entire structural image of Nankai Trough subduction seismogenic zone, a wide-angle reflection/refraction survey across the coseismic rupture zone of the Tonankai earthquake was conducted in 2004. This research is part of "Structure research on plate dynamics of the presumed rupture zone of the Tonankai-Nankai Earthquakes" funded by Ministry of Education, Culture, Sports, Science and Technology. The result of structural image shows a bit thicker oceanic crust (>8km) subducting landward, and the existence of oceanic sub-Moho reflectors in the uppermost mantle. The aftershocks of the 2004 off Kii Peninsula earthquake are distributed within the oceanic crust and the uppermantle, which is not consistent with the estimated fault plane of main shock. Comparing the structural image with this aftershock distribution and usual seismicity in the uppermost mantle, the depth of the oceanic sub-Moho reflectors and the intraslab events within the uppermantle are both distributed around 20km. We consider that such sub-Moho reflectors may become a seismic fault of intraslab earthquakes.

  8. Earthquake Testing

    NASA Technical Reports Server (NTRS)

    1979-01-01

    During NASA's Apollo program, it was necessary to subject the mammoth Saturn V launch vehicle to extremely forceful vibrations to assure the moonbooster's structural integrity in flight. Marshall Space Flight Center assigned vibration testing to a contractor, the Scientific Services and Systems Group of Wyle Laboratories, Norco, California. Wyle-3S, as the group is known, built a large facility at Huntsville, Alabama, and equipped it with an enormously forceful shock and vibration system to simulate the liftoff stresses the Saturn V would encounter. Saturn V is no longer in service, but Wyle-3S has found spinoff utility for its vibration facility. It is now being used to simulate earthquake effects on various kinds of equipment, principally equipment intended for use in nuclear power generation. Government regulations require that such equipment demonstrate its ability to survive earthquake conditions. In upper left photo, Wyle3S is preparing to conduct an earthquake test on a 25ton diesel generator built by Atlas Polar Company, Ltd., Toronto, Canada, for emergency use in a Canadian nuclear power plant. Being readied for test in the lower left photo is a large circuit breaker to be used by Duke Power Company, Charlotte, North Carolina. Electro-hydraulic and electro-dynamic shakers in and around the pit simulate earthquake forces.

  9. Evaluating the micronutrient status of women of child-bearing age living in the rural disaster areas one year after Wenchuan Earthquake.

    PubMed

    Dong, Caixia; Ge, Pengfei; Ren, Xiaolan; Zhao, Xianfeng; Fan, Haoqiang; Yin, Shi-An; Weiderpass, Elisabete

    2014-01-01

    Populations with special physiological state, such as pregnant, nursing and women of child-bearing age, have been identified as nutritionally vulnerable during natural disaster. The objective of this survey was to evaluate the prevalence of anaemia and micronutrient status of women of reproductive age in April 2009 one year after the Wenchuan Earthquake. The survey recruited 58 pregnant, 66 lactating and 242 women of child-bearing age from 19 to 45 years. The concentrations of haemoglobin in whole blood and ferritin and micronutrients in serum were assayed. Among the three groups (pregnant, nursing and child-bearing women), respectively, the prevalence of anaemia was 29.1%, 25.5% and 28.8%; that of iron deficiency was 45.4%, 49.0% and 52.9%; and that of zinc deficiency was 45.4%, 23.0% and 33.5%. The sum of vitamin D deficiency and insufficiency was more than 90% in each group, and the total vitamin B12 deficiency and marginal deficiency prevalence percentages were 47.3%, 17.7% and 35.7%, respectively. The prevalence of vitamin A deficiency and marginal deficiency was 1.8% and 9.1% in pregnant women, 6.1% and 15.2% in nursing women and 8.6% and 21.3% in women of child-bearing age, respectively. Our findings indicated that the micronutrient status of women of reproductive age was poor in the disaster areas. Therefore, improving the micronutrient status of these women should be an urgent priority in these areas.

  10. Characterization of the San Jacinto Fault Zone Northwest of the Trifurcation Area from Earthquake Data Recorded by a Dense Linear Array

    NASA Astrophysics Data System (ADS)

    Share, P. E.; Ben-Zion, Y.; Ross, Z.; Qiu, H.; Vernon, F.

    2015-12-01

    Data generated by earthquakes and recorded by a linear seismic array at Blackburn saddle NW of the trifurcation area, crossing the Clark branch of the San Jacinto Fault Zone, are used to study the internal fault zone structure in the area. The linear array (BB) is 180 m long and comprises 7 broadband three-component 1-Hz seismometers. Automatic algorithms are used to detect P and S body waves and fault zone head and trapped waves. Statistical analyses of P body wave travel times of 765 events, occurring during 2012-2014 within a 110 by 20 km window centered along the length of the Clark fault, show a 0.6-0.8 % gradual increase in slowness from the SW most (BB01) to the NE most (BB07) station. The results suggest the NE most stations overlie a zone of greater damage. Sharp velocity contrasts across the fault are imaged using fault zone head waves. In total, 72 events (within the same 110 by 20 km window) are found to produce phases with clear head wave characteristics. Further analysis of the candidate events leads to the characterization of two separate groups. The first, consisting of 51 events within approximately 11 km epicentral distance from the array, shows a clear increase of head to P body wave differential times with increasing along fault distance. Based on this moveout, an average velocity contrast across of the fault of 4 % (SW block is slower) is calculated for the portion of the Clark Fault beneath the array. Differential times for the second group show no moveout with along fault distance, suggesting a local secondary bimaterial interface with limited along-strike and/or depth extent. Events located in a broad region that also includes the San Andreas and Elsinore Faults produce candidate trapped waves that are most clear at stations BB05, BB06 and BB07 (the three NE most stations). Waveform modeling results will be presented in the meeting.

  11. Earthquake damage to schools

    USGS Publications Warehouse

    McCullough, Heather

    1994-01-01

    These unusual slides show earthquake damage to school and university buildings around the world. They graphically illustrate the potential danger to our schools, and to the welfare of our children, that results from major earthquakes. The slides range from Algeria, where a collapsed school roof is held up only by students' desks; to Anchorage, Alaska, where an elementary school structure has split in half; to California and other areas, where school buildings have sustained damage to walls, roofs, and chimneys. Interestingly, all the United States earthquakes depicted in this set of slides occurred either on a holiday or before or after school hours, except the 1935 tremor in Helena, Montana, which occurred at 11:35 am. It undoubtedly would have caused casualties had the schools not been closed days earlier by Helena city officials because of a damaging foreshock. Students in Algeria, the People's Republic of China, Armenia, and other stricken countries were not so fortunate. This set of slides represents 17 destructive earthquakes that occurred in 9 countries, and covers more than a century--from 1886 to 1988. Two of the tremors, both of which occurred in the United States, were magnitude 8+ on the Richter Scale, and four were magnitude 7-7.9. The events represented by the slides (see table below) claimed more than a quarter of a million lives.

  12. Do buried-rupture earthquakes trigger less landslides than surface-rupture earthquakes for reverse faults?

    NASA Astrophysics Data System (ADS)

    Xu, Chong

    2014-07-01

    Gorum et al. (2013, Geomorphology 184, 127-138) carried out a study on inventory compilation and statistical analyses of landslides triggered by the 2010 Mw 7.0 Haiti earthquake. They revealed that spatial distribution patterns of these landslides were mainly controlled by complex rupture mechanism and topography. They also suggested that blind-rupture earthquakes trigger fewer landslides than surface-rupture earthquakes on thrust reverse faults. Although a few lines of evidence indicate that buried-rupture earthquakes might trigger fewer landslides than surface-rupture earthquakes on reverse faults, more careful comparisons and analyses indicate that it is not always true. Instead, some cases show that a buried-rupture earthquake can trigger a larger quantity of landslides that are distributed in a larger area, whereas surface-rupture earthquakes can trigger larger but a fewer landslides distributed in a smaller area.

  13. Horizontal to vertical spectral ratio measurements in Port-au-Prince (Haiti) area damaged by the 2010 Haiti earthquake

    NASA Astrophysics Data System (ADS)

    Navarro, M.; Enomoto, T.; Benito, B.; Belizaire, D.; Navarro, D.; García-Jerez, A.; Dorfeuille, J.

    2013-05-01

    In order to evaluate ground shaking characteristics due to surface soil layers in the urban area of Port-au-Prince, short-period ambient noise observation has been performed approximately in a 500x500m grid. The HVSR method was applied to this set of 36 ambient noise measurement points to determine a distribution map of soil predominant periods. This map reveals a general increasing trend in the period values, from the Miocene conglomerates in the northern and southern parts of the town to the central and western zones formed of Pleistocene and Holocene alluvial deposits respectively, where the shallow geological materials that cover the basement increase in thickness. Shorter predominant periods (less than 0.3 s) were found in mountainous and neighbouring zones, where the thickness of sediments is smaller whereas longer periods (greater than 0.5 s) appear in Holocene alluvial fans, where the thickness of sediments is larger. The shallow shear-wave velocity structure have been estimated by means of inversion of Rayleigh wave dispersion data obtained from vertical-component array records of ambient noise. The measurements were carried out at one open space located in Holocene alluvial deposits, using 3 regular pentagonal arrays with 5, 10 and 20m respectively. Reliable dispersion curves were retrieved for frequencies between 4.0 and 14 Hz, with phase velocity values ranging from 420m/s down to 270 m/s. Finally, the average shear-wave velocity of the upper 30 m (VS30) was inverted for characterization of this geological unit.

  14. Earthquakes in Virginia and vicinity 1774 - 2004

    USGS Publications Warehouse

    Tarr, Arthur C.; Wheeler, Russell L.

    2006-01-01

    This map summarizes two and a third centuries of earthquake activity. The seismic history consists of letters, journals, diaries, and newspaper and scholarly articles that supplement seismograph recordings (seismograms) dating from the early twentieth century to the present. All of the pre-instrumental (historical) earthquakes were large enough to be felt by people or to cause shaking damage to buildings and their contents. Later, widespread use of seismographs meant that tremors too small or distant to be felt could be detected and accurately located. Earthquakes are a legitimate concern in Virginia and parts of adjacent States. Moderate earthquakes cause slight local damage somewhere in the map area about twice a decade on the average. Additionally, many buildings in the map area were constructed before earthquake protection was added to local building codes. The large map shows all historical and instrumentally located earthquakes from 1774 through 2004.

  15. Blue Mountain Lake, New York, earthquake of October 7, 1983.

    USGS Publications Warehouse

    Wendt, G.

    1984-01-01

    The October 7 earthquake near Blue Mountain Lake in the central Adirondack Mountains registered a preliminary Richter magnitude of 5.2. It was widely felt throughout the Northeastern United States and Canada and occurred in an area that has been periodically shaken by earthquakes throughout recorded history. Since 1737, at least 346 felt earthquakes have occurred in New York; an earthquake of similar magnitude last shook the Blue Mountain Lake area on June 9, 1975.    

  16. America's faulty earthquake plans

    SciTech Connect

    Rosen, J

    1989-10-01

    In this article, the author discusses the liklihood of major earthquakes in both the western and eastern United States as well as the level of preparedness of each region of the U.S. for a major earthquake. Current technology in both earthquake-resistance design and earthquake detection is described. Governmental programs for earthquake hazard reduction are outlined and critiqued.

  17. Spatiotemporal model for crustal deformation around the focal area of the 2008 Iwate-Miyagi Inland Earthquake, northeastern Japan, estimated by GPS and InSAR

    NASA Astrophysics Data System (ADS)

    Ohzono, M.; McCaffrey, R.; Ohta, Y.; Miura, S.; Iinuma, T.; Tachibana, K.; Sato, T.

    2009-12-01

    Applying the program tDEFNODE [McCaffrey, GRL09] to model elastic lithospheric block rotations and strains, and locking or coseismic slip on block-bounding faults, we model GPS and InSAR data of crustal deformation before and after the 2008 M7.2 Iwate-Miyagi Inland Earthquake (IMEQ). The epicenter of the IMEQ is located in a high strain rate zone along the Ou Backbone Range (OBR) in northeastern Japan, where volcanic front runs subparallel to the Japan Trench. Along eastern and western margin of the OBR, major inland active faults have been growing. In order to clarify detailed strain field around these active faults, Japan Nuclear Energy Safety Organization (JNES) installed 7 new continuous GPS sites with ~5 km spacing across the Dedana Fault (DF), which is a part of the eastern marginal active faults, in October 2007. Because the DF is located at only ~20 km northeast from the hypocenter of the IMEQ, the detailed coseismic and postseismic crustal deformation was obtained at these GPS sites [Ohta et al., EPS08; Iinuma et al., GRL09]. Takada et al. [EPS09] also estimated coseismic faults from InSAR with pixel-offset method. These studies, however, handled each data independently. We unify both GPS and InSAR data to model crustal deformation over inter-, co-, and post-seismic period using tDEFNODE. This code interprets geodetic timeseries data by assuming elastic block rotation, transient phenomena such as slow slip, and coseismic slip, on the block boundary faults. We use timeseries data obtained by continuous GPS networks conducted by JNES, Tohoku University, Geographical Survey Institute (GSI), National Astronomical Observatory (NAO), and IGS from 2006 to June 2009, together with a temporal network for postseismic deformation installed by Japanese University Consortium for GPS Research (JUNCO). InSAR data is obtained by analyzing images of ALOS/PALSAR mission. We presumed three blocks in the study area divided by two boundary faults. We expressed the time

  18. NEIC; the National Earthquake Information Center

    USGS Publications Warehouse

    Masse, R.P.; Needham, R.E.

    1989-01-01

    At least 9,500 people were killed, 30,000 were injured and 100,000 were left homeless by this earthquake. According to some unconfirmed reports, the death toll from this earthquake may have been as high as 35,000. this earthquake is estimated to have seriously affected an area of 825,000 square kilometers, caused between 3 and 4 billion dollars in damage, and been felt by 20 million people. 

  19. TP0326, a Treponema pallidum β-barrel assembly machinery A (BamA) orthologue and rare outer membrane protein.

    PubMed

    Desrosiers, Daniel C; Anand, Arvind; Luthra, Amit; Dunham-Ems, Star M; LeDoyt, Morgan; Cummings, Michael A D; Eshghi, Azad; Cameron, Caroline E; Cruz, Adriana R; Salazar, Juan C; Caimano, Melissa J; Radolf, Justin D

    2011-06-01

    Definitive identification of Treponema pallidum rare outer membrane proteins (OMPs) has long eluded researchers. TP0326, the sole protein in T. pallidum with sequence homology to a Gram-negative OMP, belongs to the BamA family of proteins essential for OM biogenesis. Structural modelling predicted that five polypeptide transport-associated (POTRA) domains comprise the N-terminus of TP0326, while the C-terminus forms an 18-stranded amphipathic β-barrel. Circular dichroism, heat modifiability by SDS-PAGE, Triton X-114 phase partitioning and liposome incorporation supported these topological predictions and confirmed that the β-barrel is responsible for the native protein's amphiphilicity. Expression analyses revealed that native TP0326 is expressed at low abundance, while a protease-surface accessibility assay confirmed surface exposure. Size-exclusion chromatography and blue native polyacrylamide gel electrophoresis revealed a modular Bam complex in T. pallidum larger than that of Escherichia coli. Non-orthologous ancillary factors and self-association of TP0326 via its β-barrel may both contribute to the Bam complex. T. pallidum-infected rabbits mount a vigorous antibody response to both POTRA and β-barrel portions of TP0326, whereas humans with secondary syphilis respond predominantly to POTRA. The syphilis spirochaete appears to have devised a stratagem for harnessing the Bam pathway while satisfying its need to limit surface antigenicity. PMID:21488980

  20. Fault tectonics and earthquake hazards in parts of southern California. [penninsular ranges, Garlock fault, Salton Trough area, and western Mojave Desert

    NASA Technical Reports Server (NTRS)

    Merifield, P. M. (Principal Investigator); Lamar, D. L.; Gazley, C., Jr.; Lamar, J. V.; Stratton, R. H.

    1976-01-01

    The author has identified the following significant results. Four previously unknown faults were discovered in basement terrane of the Peninsular Ranges. These have been named the San Ysidro Creek fault, Thing Valley fault, Canyon City fault, and Warren Canyon fault. In addition fault gouge and breccia were recognized along the San Diego River fault. Study of features on Skylab imagery and review of geologic and seismic data suggest that the risk of a damaging earthquake is greater along the northwestern portion of the Elsinore fault than along the southeastern portion. Physiographic indicators of active faulting along the Garlock fault identifiable in Skylab imagery include scarps, linear ridges, shutter ridges, faceted ridges, linear valleys, undrained depressions and offset drainage. The following previously unrecognized fault segments are postulated for the Salton Trough Area: (1) An extension of a previously known fault in the San Andreas fault set located southeast of the Salton Sea; (2) An extension of the active San Jacinto fault zone along a tonal change in cultivated fields across Mexicali Valley ( the tonal change may represent different soil conditions along opposite sides of a fault). For the Skylab and LANDSAT images studied, pseudocolor transformations offer no advantages over the original images in the recognition of faults in Skylab and LANDSAT images. Alluvial deposits of different ages, a marble unit and iron oxide gossans of the Mojave Mining District are more readily differentiated on images prepared from ratios of individual bands of the S-192 multispectral scanner data. The San Andreas fault was also made more distinct in the 8/2 and 9/2 band ratios by enhancement of vegetation differences on opposite sides of the fault. Preliminary analysis indicates a significant earth resources potential for the discrimination of soil and rock types, including mineral alteration zones. This application should be actively pursued.

  1. Structural Analysis of Recent and Active Faults and Regional State of Stress in the Epicentral Area of the 1978 Thessaloniki Earthquakes (northern Greece)

    NASA Astrophysics Data System (ADS)

    Mercier, Jacques-Louis; Carey-Gailhardis, Evelyne; Mouyaris, Nicolas; Simeakis, Konstantinos; Roundoyannis, Theodora; Anghelidhis, Christos

    1983-12-01

    During spring and summer 1978, Macedonia (Greece) suffered damaging seismic activity. During the two main shocks which occurred on May 23 (Mb = 5.7) and June 20 (Mb = 6.1), seismic open cracks and faults were formed in the epicentral area, 25 km NNE from Thessaloniki. They have been mapped and their kinematics analyzed. These studies have shown that they result from the reactivation of existing faults of Pleistocene, Recent, and historical age and that the crust is stretching along a N-S to NNE-SSW direction in that part of the North Aegean. Principal stress directions have been computed from the slip vectors measured on recent neotectonic faults and seismic cracks and faults, this computation utilizing a simple mechanical model (homogeneous deformation through the addition of small and independent displacements of rigid blocks in a highly fractured body). A striking feature of this analysis is that the tensional directions σ3 deduced from seismic faulting and from recent neotectonic faulting are nearly the same. They are compatible with the regional tension axis deduced from focal mechanisms of North Aegean and with the focal mechanisms of the 1978 Thessaloniki main shocks. They are also compatible with in situ stress measurements in this region. Studies of superficial seismic faulting strongly support previous assumptions proposed from aftershock distribution: the 1978 Thessaloniki earthquakes resulted from reactivation of several different faults situated within the same NE dipping fault zone of Upper Eocene-Lower Oligocene age (and older) separating the Serbo-Macedonian Massif from the Peonias (East Vardar) zone.

  2. Eczema and Asthma Symptoms among Schoolchildren in Coastal and Inland Areas after the 2011 Great East Japan Earthquake: The ToMMo Child Health Study.

    PubMed

    Miyashita, Masako; Kikuya, Masahiro; Yamanaka, Chizuru; Ishikuro, Mami; Obara, Taku; Sato, Yuki; Metoki, Hirohito; Nakaya, Naoki; Nagami, Fuji; Tomita, Hiroaki; Kiyomoto, Hideyasu; Sugawara, Junichi; Hozawa, Atsushi; Fuse, Nobuo; Suzuki, Yoichi; Tsuji, Ichiro; Kure, Shigeo; Yaegashi, Nobuo; Yamamoto, Masayuki; Kuriyama, Shinichi

    2015-01-01

    After the Great East Japan Earthquake of 2011, there has been a concern about health problems among children. Therefore, we investigated the prevalence of wheeze and eczema symptoms and associated factors among children in areas primarily affected by the disaster. From 2012 to 2014, we distributed the parent-administered questionnaire to 25,198 children in all 233 public schools in the 13 municipalities of Miyagi Prefecture in northeast Japan. A total of 7,155 responses (mean age 10.5 ± 2.2 years) were received (response rate: 28.4%). The prevalence of allergic symptoms according to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire in 2nd, 4th, 6th, and 8th graders was 12.4%, 9.9%, 9.3%, and 5.6% for wheeze, and 20.1%, 18.0%, 14.0%, and 12.4% for eczema. In multivariate logistic analysis, younger age, history of hospitalization, and difficulties in children's daily lives as assessed by the Strengths and Difficulties Questionnaire (SDQ), were significantly and consistently associated with both allergic symptoms (both P < 0.05). Living in a coastal municipality was also associated with eczema symptoms (P = 0.0278). The prevalence of eczema symptoms in the 2nd (20.1%) and 8th (12.4%) grades was significantly higher than previously reported in Japan. Living in a coastal municipality was independently associated with eczema symptoms, and psychometric properties were also closely linked to allergic symptoms. These findings are clinically important for understanding the risks of allergic disorders after natural disasters.

  3. Earthquake Apparent Stress Scaling

    NASA Astrophysics Data System (ADS)

    Mayeda, K.; Walter, W. R.

    2003-04-01

    There is currently a disagreement within the geophysical community on the way earthquake energy scales with magnitude. One set of recent papers finds evidence that energy release per seismic moment (apparent stress) is constant (e.g. Choy and Boatwright, 1995; McGarr, 1999; Ide and Beroza, 2001). Another set of recent papers finds the apparent stress increases with magnitude (e.g. Kanamori et al., 1993 Abercrombie, 1995; Mayeda and Walter, 1996; Izutani and Kanamori, 2001). The resolution of this issue is complicated by the difficulty of accurately accounting for and determining the seismic energy radiated by earthquakes over a wide range of event sizes in a consistent manner. We have just started a project to reexamine this issue by applying the same methodology to a series of datasets that spans roughly 10 orders in seismic moment, M0. We will summarize recent results using a coda envelope methodology of Mayeda et al, (2003) which provide the most stable source spectral estimates to date. This methodology eliminates the complicating effects of lateral path heterogeneity, source radiation pattern, directivity, and site response (e.g., amplification, f-max and kappa). We find that in tectonically active continental crustal areas the total radiated energy scales as M00.25 whereas in regions of relatively younger oceanic crust, the stress drop is generally lower and exhibits a 1-to-1 scaling with moment. In addition to answering a fundamental question in earthquake source dynamics, this study addresses how one would scale small earthquakes in a particular region up to a future, more damaging earthquake. 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.

  4. Patterns of Seismicity Characterizing the Earthquake Cycle

    NASA Astrophysics Data System (ADS)

    Rundle, J. B.; Turcotte, D. L.; Yoder, M. R.; Holliday, J. R.; Schultz, K.; Wilson, J. M.; Donnellan, A.; Grant Ludwig, L.

    2015-12-01

    A number of methods to calculate probabilities of major earthquakes have recently been proposed. Most of these methods depend upon understanding patterns of small earthquakes preceding the large events. For example, the Natural Time Weibull method for earthquake forecasting (see www.openhazards.com) is based on the assumption that large earthquakes complete the Gutenberg-Richter scaling relation defined by the smallest earthquakes. Here we examine the scaling patterns of small earthquakes having magnitudes between cycles of large earthquakes. For example, in the region of California-Nevada between longitudes -130 to -114 degrees W, and latitudes 32 to 45 degrees North, we find 79 earthquakes having magnitudes M6 during the time interval 1933 - present, culminating with the most recent event, the M6.0 Napa, California earthquake of August 24, 2014. Thus we have 78 complete cycles of large earthquakes in this region. After compiling and stacking the smaller events occurring between the large events, we find a characteristic pattern of scaling for the smaller events. This pattern shows a scaling relation for the smallest earthquakes up to about 3earthquakes for 4.5earthquake having M~6.4. In addition, statistics indicate that departure of the successive earthquake cycles from their average pattern can be characterized by Coefficients of Variability and other measures. We discuss these ideas and apply them not only to California, but also to other seismically active areas in the world

  5. Darwin's earthquake.

    PubMed

    Lee, Richard V

    2010-07-01

    Charles Darwin experienced a major earthquake in the Concepción-Valdivia region of Chile 175 years ago, in February 1835. His observations dramatically illustrated the geologic principles of James Hutton and Charles Lyell which maintained that the surface of the earth was subject to alterations by natural events, such as earthquakes, volcanoes, and the erosive action of wind and water, operating over very long periods of time. Changes in the land created new environments and fostered adaptations in life forms that could lead to the formation of new species. Without the demonstration of the accumulation of multiple crustal events over time in Chile, the biologic implications of the specific species of birds and tortoises found in the Galapagos Islands and the formulation of the concept of natural selection might have remained dormant.

  6. Geochemical challenge to earthquake prediction.

    PubMed Central

    Wakita, H

    1996-01-01

    The current status of geochemical and groundwater observations for earthquake prediction in Japan is described. The development of the observations is discussed in relation to the progress of the earthquake prediction program in Japan. Three major findings obtained from our recent studies are outlined. (i) Long-term radon observation data over 18 years at the SKE (Suikoen) well indicate that the anomalous radon change before the 1978 Izu-Oshima-kinkai earthquake can with high probability be attributed to precursory changes. (ii) It is proposed that certain sensitive wells exist which have the potential to detect precursory changes. (iii) The appearance and nonappearance of coseismic radon drops at the KSM (Kashima) well reflect changes in the regional stress state of an observation area. In addition, some preliminary results of chemical changes of groundwater prior to the 1995 Kobe (Hyogo-ken nanbu) earthquake are presented. PMID:11607665

  7. The Evolutionary History of MAPL (Mitochondria-Associated Protein Ligase) and Other Eukaryotic BAM/GIDE Domain Proteins.

    PubMed

    Wideman, Jeremy G; Moore, Blake P

    2015-01-01

    MAPL (mitochondria-associated protein ligase, also called MULAN/GIDE/MUL1) is a multifunctional mitochondrial outer membrane protein found in human cells that contains a unique BAM (beside a membrane) domain and a C-terminal RING-finger domain. MAPL has been implicated in several processes that occur in animal cells such as NF-kB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. Previous studies demonstrated that the BAM domain is present in diverse organisms in which most of these processes do not occur, including plants, archaea, and bacteria. Thus the conserved function of MAPL and its BAM domain remains an open question. In order to gain insight into its conserved function, we investigated the evolutionary origins of MAPL by searching for homologues in predicted proteomes of diverse eukaryotes. We show that MAPL proteins with a conserved BAM-RING architecture are present in most animals, protists closely related to animals, a single species of fungus, and several multicellular plants and related green algae. Phylogenetic analysis demonstrated that eukaryotic MAPL proteins originate from a common ancestor and not from independent horizontal gene transfers from bacteria. We also determined that two independent duplications of MAPL occurred, one at the base of multicellular plants and another at the base of vertebrates. Although no other eukaryote genome examined contained a verifiable MAPL orthologue, BAM domain-containing proteins were identified in the protists Bigelowiella natans and Ectocarpus siliculosis. Phylogenetic analyses demonstrated that these proteins are more closely related to prokaryotic BAM proteins and therefore likely arose from independent horizontal gene transfers from bacteria. We conclude that MAPL proteins with BAM-RING architectures have been present in the holozoan and viridiplantae lineages since their very beginnings. Our work paves

  8. The Evolutionary History of MAPL (Mitochondria-Associated Protein Ligase) and Other Eukaryotic BAM/GIDE Domain Proteins.

    PubMed

    Wideman, Jeremy G; Moore, Blake P

    2015-01-01

    MAPL (mitochondria-associated protein ligase, also called MULAN/GIDE/MUL1) is a multifunctional mitochondrial outer membrane protein found in human cells that contains a unique BAM (beside a membrane) domain and a C-terminal RING-finger domain. MAPL has been implicated in several processes that occur in animal cells such as NF-kB activation, innate immunity and antiviral signaling, suppression of PINK1/parkin defects, mitophagy in skeletal muscle, and caspase-dependent apoptosis. Previous studies demonstrated that the BAM domain is present in diverse organisms in which most of these processes do not occur, including plants, archaea, and bacteria. Thus the conserved function of MAPL and its BAM domain remains an open question. In order to gain insight into its conserved function, we investigated the evolutionary origins of MAPL by searching for homologues in predicted proteomes of diverse eukaryotes. We show that MAPL proteins with a conserved BAM-RING architecture are present in most animals, protists closely related to animals, a single species of fungus, and several multicellular plants and related green algae. Phylogenetic analysis demonstrated that eukaryotic MAPL proteins originate from a common ancestor and not from independent horizontal gene transfers from bacteria. We also determined that two independent duplications of MAPL occurred, one at the base of multicellular plants and another at the base of vertebrates. Although no other eukaryote genome examined contained a verifiable MAPL orthologue, BAM domain-containing proteins were identified in the protists Bigelowiella natans and Ectocarpus siliculosis. Phylogenetic analyses demonstrated that these proteins are more closely related to prokaryotic BAM proteins and therefore likely arose from independent horizontal gene transfers from bacteria. We conclude that MAPL proteins with BAM-RING architectures have been present in the holozoan and viridiplantae lineages since their very beginnings. Our work paves

  9. Connecting slow earthquakes to huge earthquakes.

    PubMed

    Obara, Kazushige; Kato, Aitaro

    2016-07-15

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes.

  10. Connecting slow earthquakes to huge earthquakes

    NASA Astrophysics Data System (ADS)

    Obara, Kazushige; Kato, Aitaro

    2016-07-01

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes.

  11. Connecting slow earthquakes to huge earthquakes.

    PubMed

    Obara, Kazushige; Kato, Aitaro

    2016-07-15

    Slow earthquakes are characterized by a wide spectrum of fault slip behaviors and seismic radiation patterns that differ from those of traditional earthquakes. However, slow earthquakes and huge megathrust earthquakes can have common slip mechanisms and are located in neighboring regions of the seismogenic zone. The frequent occurrence of slow earthquakes may help to reveal the physics underlying megathrust events as useful analogs. Slow earthquakes may function as stress meters because of their high sensitivity to stress changes in the seismogenic zone. Episodic stress transfer to megathrust source faults leads to an increased probability of triggering huge earthquakes if the adjacent locked region is critically loaded. Careful and precise monitoring of slow earthquakes may provide new information on the likelihood of impending huge earthquakes. PMID:27418504

  12. Alview: Portable Software for Viewing Sequence Reads in BAM Formatted Files.

    PubMed

    Finney, Richard P; Chen, Qing-Rong; Nguyen, Cu V; Hsu, Chih Hao; Yan, Chunhua; Hu, Ying; Abawi, Massih; Bian, Xiaopeng; Meerzaman, Daoud M

    2015-01-01

    The name Alview is a contraction of the term Alignment Viewer. Alview is a compiled to native architecture software tool for visualizing the alignment of sequencing data. Inputs are files of short-read sequences aligned to a reference genome in the SAM/BAM format and files containing reference genome data. Outputs are visualizations of these aligned short reads. Alview is written in portable C with optional graphical user interface (GUI) code written in C, C++, and Objective-C. The application can run in three different ways: as a web server, as a command line tool, or as a native, GUI program. Alview is compatible with Microsoft Windows, Linux, and Apple OS X. It is available as a web demo at https://cgwb.nci.nih.gov/cgi-bin/alview. The source code and Windows/Mac/Linux executables are available via https://github.com/NCIP/alview.

  13. New exponential stability criteria for stochastic BAM neural networks with impulses

    NASA Astrophysics Data System (ADS)

    Sakthivel, R.; Samidurai, R.; Anthoni, S. M.

    2010-10-01

    In this paper, we study the global exponential stability of time-delayed stochastic bidirectional associative memory neural networks with impulses and Markovian jumping parameters. A generalized activation function is considered, and traditional assumptions on the boundedness, monotony and differentiability of activation functions are removed. We obtain a new set of sufficient conditions in terms of linear matrix inequalities, which ensures the global exponential stability of the unique equilibrium point for stochastic BAM neural networks with impulses. The Lyapunov function method with the Itô differential rule is employed for achieving the required result. Moreover, a numerical example is provided to show that the proposed result improves the allowable upper bound of delays over some existing results in the literature.

  14. Alview: Portable Software for Viewing Sequence Reads in BAM Formatted Files

    PubMed Central

    Finney, Richard P; Chen, Qing-Rong; Nguyen, Cu V; Hsu, Chih Hao; Yan, Chunhua; Hu, Ying; Abawi, Massih; Bian, Xiaopeng; Meerzaman, Daoud M

    2015-01-01

    The name Alview is a contraction of the term Alignment Viewer. Alview is a compiled to native architecture software tool for visualizing the alignment of sequencing data. Inputs are files of short-read sequences aligned to a reference genome in the SAM/BAM format and files containing reference genome data. Outputs are visualizations of these aligned short reads. Alview is written in portable C with optional graphical user interface (GUI) code written in C, C++, and Objective-C. The application can run in three different ways: as a web server, as a command line tool, or as a native, GUI program. Alview is compatible with Microsoft Windows, Linux, and Apple OS X. It is available as a web demo at https://cgwb.nci.nih.gov/cgi-bin/alview. The source code and Windows/Mac/Linux executables are available via https://github.com/NCIP/alview. PMID:26417198

  15. Global robust asymptotic stability of variable-time impulsive BAM neural networks.

    PubMed

    Saylı, Mustafa; Yılmaz, Enes

    2014-12-01

    In this paper, the global robust asymptotic stability of the equilibrium point for a more general class of bidirectional associative memory (BAM) neural networks with variable time of impulses is addressed. Unlike most existing studies, the case of non-fix time impulses is focused on in the present study. By means of B-equivalence method, which was introduced in Akhmet (2003, 2005, 2009, 2010), Akhmet and Perestyuk (1990) and Akhmet and Turan (2009), we reduce these networks to a fix time impulsive neural networks system. Sufficient conditions ensuring the existence, uniqueness and global robust asymptotic stability of the equilibrium point are obtained by employing an appropriate Lyapunov function and linear matrix inequality (LMI). Finally, we give one illustrative example to show the effectiveness of the theoretical results.

  16. Modeling earthquake indexes derived from the earthquake warning system upon the planet earth

    NASA Astrophysics Data System (ADS)

    Li, Yong

    2010-12-01

    By studying the correlation between historical earthquake data and the distributional characteristics of parameters of solid earth tides in the earthquake epicenter, we are able to design a forecasting function of earthquake probability. We put forward a design method for the Earthquake Warning System. The model could theoretically simulate and be used to predict the probability of strong earthquakes that could occur anywhere at any time. In addition, the system could also conveniently obtain global or partial Modeling Earthquake Indexes to finally combine the precise pointing prediction and forecast of partial indexes. The literature quotes global data values, provided by NEIC, of 1544 M ⩾ 6.5 earthquakes. It also gives examples of instantaneous earthquake indexes of the whole world and Taiwan Area on 1st January 2010, UT=0:00 and the average earthquake index near the Taiwan Area. According to the 10-year pointing prediction of strong earthquakes in San Francisco, the literature provides the average earthquake index on 24th June 2015 (± 15 days), in its neighborhood.

  17. Earthquake and tsunami forecasts: relation of slow slip events to subsequent earthquake rupture.

    PubMed

    Dixon, Timothy H; Jiang, Yan; Malservisi, Rocco; McCaffrey, Robert; Voss, Nicholas; Protti, Marino; Gonzalez, Victor

    2014-12-01

    The 5 September 2012 M(w) 7.6 earthquake on the Costa Rica subduction plate boundary followed a 62-y interseismic period. High-precision GPS recorded numerous slow slip events (SSEs) in the decade leading up to the earthquake, both up-dip and down-dip of seismic rupture. Deeper SSEs were larger than shallower ones and, if characteristic of the interseismic period, release most locking down-dip of the earthquake, limiting down-dip rupture and earthquake magnitude. Shallower SSEs were smaller, accounting for some but not all interseismic locking. One SSE occurred several months before the earthquake, but changes in Mohr-Coulomb failure stress were probably too small to trigger the earthquake. Because many SSEs have occurred without subsequent rupture, their individual predictive value is limited, but taken together they released a significant amount of accumulated interseismic strain before the earthquake, effectively defining the area of subsequent seismic rupture (rupture did not occur where slow slip was common). Because earthquake magnitude depends on rupture area, this has important implications for earthquake hazard assessment. Specifically, if this behavior is representative of future earthquake cycles and other subduction zones, it implies that monitoring SSEs, including shallow up-dip events that lie offshore, could lead to accurate forecasts of earthquake magnitude and tsunami potential.

  18. Earthquake and tsunami forecasts: Relation of slow slip events to subsequent earthquake rupture

    PubMed Central

    Dixon, Timothy H.; Jiang, Yan; Malservisi, Rocco; McCaffrey, Robert; Voss, Nicholas; Protti, Marino; Gonzalez, Victor

    2014-01-01

    The 5 September 2012 Mw 7.6 earthquake on the Costa Rica subduction plate boundary followed a 62-y interseismic period. High-precision GPS recorded numerous slow slip events (SSEs) in the decade leading up to the earthquake, both up-dip and down-dip of seismic rupture. Deeper SSEs were larger than shallower ones and, if characteristic of the interseismic period, release most locking down-dip of the earthquake, limiting down-dip rupture and earthquake magnitude. Shallower SSEs were smaller, accounting for some but not all interseismic locking. One SSE occurred several months before the earthquake, but changes in Mohr–Coulomb failure stress were probably too small to trigger the earthquake. Because many SSEs have occurred without subsequent rupture, their individual predictive value is limited, but taken together they released a significant amount of accumulated interseismic strain before the earthquake, effectively defining the area of subsequent seismic rupture (rupture did not occur where slow slip was common). Because earthquake magnitude depends on rupture area, this has important implications for earthquake hazard assessment. Specifically, if this behavior is representative of future earthquake cycles and other subduction zones, it implies that monitoring SSEs, including shallow up-dip events that lie offshore, could lead to accurate forecasts of earthquake magnitude and tsunami potential. PMID:25404327

  19. Earthquakes and plate tectonics.

    USGS Publications Warehouse

    Spall, H.

    1982-01-01

    Earthquakes occur at the following three kinds of plate boundary: ocean ridges where the plates are pulled apart, margins where the plates scrape past one another, and margins where one plate is thrust under the other. Thus, we can predict the general regions on the earth's surface where we can expect large earthquakes in the future. We know that each year about 140 earthquakes of magnitude 6 or greater will occur within this area which is 10% of the earth's surface. But on a worldwide basis we cannot say with much accuracy when these events will occur. The reason is that the processes in plate tectonics have been going on for millions of years. Averaged over this interval, plate motions amount to several mm per year. But at any instant in geologic time, for example the year 1982, we do not know, exactly where we are in the worldwide cycle of strain build-up and strain release. Only by monitoring the stress and strain in small areas, for instance, the San Andreas fault, in great detail can we hope to predict when renewed activity in that part of the plate tectonics arena is likely to take place. -from Author

  20. Vp structure in the largest slip area of the 2011 Tohoku-oki earthquake by airgun-ocean bottom seismometer surveys

    NASA Astrophysics Data System (ADS)

    Azuma, R.; Hino, R.; Ohta, Y.; Mochizuki, K.; Murai, Y.; Ito, Y.; Yakiwara, H.; Sato, T.; Shinohara, M.

    2015-12-01

    The huge coseismic slip during the 2011 Tohoku-oki earthquake concentrated beneath the lower inner slope of the middle Japan Trench (Miyagi region) and its amount sharply diminished along the trench within a hundred kilometers (e.g., Iinuma et al., 2012). The previous 2-D seismic study in the corresponding area found a notable Vp change in the hanging wall side of the megathrust (Azuma et al., in prep.). High-Vp body, corresponding to the rigid backstop block (Tsuru et al., 2002) was identified in the Miyagi, but was absent in the northern area. The spatial extent of the high-Vp anomaly almost coincides with the large slip zone and the correlation suggests that the heterogeneous structure in the overriding plate controlled the rupture process of the M-9 mainshock. To confirm the correlation between the seismic structure and coseismic slip distribution, we conducted a wide-angle survey in 2014 around the previous survey. In analysis, we operated a traveltime inversion for the first arrivals (Fujie et al., 2000) to obtain a rough model. Then, we made a trial-and-error adjustment of the structure model based on the travel time modeling with a 2D ray tracing (Zelt and Ellis, 1988). In the modeling, we tried to identify the location of the boundary between the backstop block and the low-Vp prism, because we assume the boundary (B/P boundary) to be correlated to the border of the high-slip zone during the 2011 event. The results showed sharp Vp transition from >3.7 km/s (backstop) to <3.4 km/s (prism) representing the B/P boundary. This feature agrees with the Vp variation or the along-trench distribution of the prism clarified by the previous studies. In the several observed record sections, there are clear shadow zone of the refracted arrivals from the backstop layer. The presence of the shadow indicates that a low Vp layer underlies the backstop, which is consistent with the previous reflection profiling made across the trench system. The low Vp prism is located

  1. LAT-independent Erk activation via Bam32-PLC-γ1-Pak1 complexes: GTPase-independent Pak1 activation.

    PubMed

    Rouquette-Jazdanian, Alexandre K; Sommers, Connie L; Kortum, Robert L; Morrison, Deborah K; Samelson, Lawrence E

    2012-10-26

    In T cells, the adaptor Bam32 is coupled to Erk activation downstream of the TCR by an unknown mechanism. We characterized in Jurkat cells and primary T lymphocytes a pathway dependent on Bam32-PLC-γ1-Pak1 complexes, in which Pak1 kinase activates Raf-1 and Mek-1, both upstream of Erk. In the Bam32-PLC-γ1-Pak1 complex, catalytically inactive PLC-γ1 is used as a scaffold linking Bam32 to Pak1. PLC-γ1(C-SH2) directly binds S141 of Bam32, preventing LAT-mediated activation of Ras by PLC-γ1. The Bam32-PLC-γ1 interaction enhances the binding of the SH3 domain of the phospholipase with Pak1. The PLC-γ1(SH3)-Pak1 interaction activates Pak1 independently of the small GTPases Rac1/Cdc42, previously described as being the only activators of Pak1 in T cells. Direct binding of the SH3 domain of PLC-γ1 to Pak1 dissociates inactive Pak1 homodimers, a mechanism required for Pak1 activation. We have thus uncovered a LAT/Ras-independent, Bam32-nucleated pathway that activates Erk signaling in T cells.

  2. Refolding, crystallization and preliminary X-ray crystallographic studies of the β-barrel domain of BamA, a membrane protein essential for outer membrane protein biogenesis.

    PubMed

    Ni, Dongchun; Yang, Kun; Huang, Yihua

    2014-03-01

    In Gram-negative bacteria, the assembly of outer membrane proteins (OMPs) requires a five-protein β-barrel assembly machinery (BAM) complex, of which BamA is an essential and evolutionarily conserved integral outer membrane protein. Here, the refolding, crystallization and preliminary X-ray crystallographic characterization of the β-barrel domain of BamA from Escherichia coli (EcBamA) are reported. Native and selenomethionine-substituted EcBamA proteins were crystallized at 16°C and X-ray diffraction data were collected to 2.6 and 3.7 Å resolution, respectively. The native crystals belonged to space group P21212, with unit-cell parameters a = 118.492, b = 159.883, c = 56.000 Å and two molecules in one asymmetric unit; selenomethionine-substituted protein crystals belonged to space group P4322, with unit-cell parameters a = b = 163.162, c = 46.388 Å and one molecule in one asymmetric unit. Initial phases for EcBamA β-barrel domain were obtained from a SeMet SAD data set. These preliminary X-ray crystallographic studies paved the way for further structural determination of the β-barrel domain of EcBamA.

  3. Nucleotide sequence of the BamHI repetitive sequence, including the HindIII fundamental unit, as a possible mobile element from the Japanese monkey Macaca fuscata.

    PubMed

    Prassolov, V S; Kuchino, Y; Nemoto, K; Nishimura, S

    1986-01-01

    Clustered repeat units produced by BamHI digestion of genomic DNA from the Japanese monkey Macaca fuscata [JMr(BamHI)] were sequenced by dideoxy DNA sequencing. The nucleotide sequences of several individual repeats showed that the BamHI repeat contains the 170-bp HindIII element as an integral part, and that it has more than 90% homology with the HindIII repeat element [AGMr(HindIII)] found in the genomic DNA of the African green monkey. In the JMr(BamHI) repeat unit, the 170-bp HindIII element is flanked by a 6-bp inverted repeat, which is part of a 22-bp direct repeat. This latter repeat of 22-bp asymmetrically overlaps the border between the internal AGMr(HindIII)-like region and adjacent regions of the JMr(BamHI) repeat. A similar structural feature of the BamHI repeat unit has been found in the genomic DNA of the baboon, but not in that of the African green monkey. These results show clearly that the BamHI repeat of the modern Japanese monkey originated as a result of insertion of an AGMr(HindIII) element into a certain site(s) of the genomic DNA of an ancestor of the modern Japanese monkey before Macaca-Cercocebus divergence.

  4. Thermoluminescence dating of Australian palaeo-earthquakes

    USGS Publications Warehouse

    Hutton, J.T.; Prescott, J.R.; Bowman, J.R.; Dunham, M.N.E.; Crone, A.J.; Machette, M.N.; Twidale, C.R.

    1994-01-01

    Thermoluminescence (TL) dating is a useful tool for determining the age of prehistoric earthquakes by dating deposits that are stratigraphically related to fault scarps that formed during the earthquakes. TL dating of aeolian sand in the area of the 1988 Tennant Creek, Northern Territory, earthquakes provides evidence that similar earthquakes have not ruptured the causative faults for at least 50 ka. Pilot TL measurements of deposits associated with the Roopena and Ash Ridge fault scarps near Whyalla on Eyre Peninsula, South Australia, suggest an age of 140 ka for the Quaternary deposits associated with the formation of the scarps. ?? 1994.

  5. Earthquakes at North Atlantic passive margins

    SciTech Connect

    Gregersen, S. ); Basham, P.W. )

    1989-01-01

    The main focus of this volume is the earthquakes that occur at and near the continental margins on both sides of the North Atlantic. The book, which contains the proceedings of the NATO workshop on Causes and Effects of Earthquakes at Passive Margins and in Areas of Postglacial Rebound on Both Sides of the North Atlantic, draws together the fields of geophysics, geology and geodesy to address the stress and strain in the Earth's crust. The resulting earthquakes produced on ancient geological fault zones and the associated seismic hazards these pose to man are also addressed. Postglacial rebound in North America and Fennoscandia is a minor source of earthquakes today, during the interglacial period, but evidence is presented to suggest that the ice sheets suppressed earthquake strain while they were in place, and released this strain as a pulse of significant earthquakes after the ice melted about 9000 years ago.

  6. Oklahoma's recent earthquakes and saltwater disposal.

    PubMed

    Walsh, F Rall; Zoback, Mark D

    2015-06-01

    Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal principally comes from "produced" water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the earthquakes are occurring. Although most of the recent earthquakes have posed little danger to the public, the possibility of triggering damaging earthquakes on potentially active basement faults cannot be discounted. PMID:26601200

  7. Oklahoma's recent earthquakes and saltwater disposal.

    PubMed

    Walsh, F Rall; Zoback, Mark D

    2015-06-01

    Over the past 5 years, parts of Oklahoma have experienced marked increases in the number of small- to moderate-sized earthquakes. In three study areas that encompass the vast majority of the recent seismicity, we show that the increases in seismicity follow 5- to 10-fold increases in the rates of saltwater disposal. Adjacent areas where there has been relatively little saltwater disposal have had comparatively few recent earthquakes. In the areas of seismic activity, the saltwater disposal principally comes from "produced" water, saline pore water that is coproduced with oil and then injected into deeper sedimentary formations. These formations appear to be in hydraulic communication with potentially active faults in crystalline basement, where nearly all the earthquakes are occurring. Although most of the recent earthquakes have posed little danger to the public, the possibility of triggering damaging earthquakes on potentially active basement faults cannot be discounted.

  8. The B Cell Adaptor Molecule Bam32 Is Critically Important for Optimal Antibody Response and Resistance to Trypanosoma congolense Infection in Mice

    PubMed Central

    Onyilagha, Chukwunonso; Jia, Ping; Jayachandran, Nipun; Hou, Sen; Okwor, Ifeoma; Kuriakose, Shiby; Marshall, Aaron; Uzonna, Jude E.

    2015-01-01

    Background Bam32, a 32 kDa adaptor molecule, plays important role in B cell receptor signalling, T cell receptor signalling and antibody affinity maturation in germinal centres. Since antibodies against trypanosome variant surface glycoproteins (VSG) are critically important for control of parasitemia, we hypothesized that Bam32 deficient (Bam32-/-) mice would be susceptible to T. congolense infection. Methodology/Principal Findings We found that T. congolense-infected Bam32-/- mice successfully control the first wave of parasitemia but then fail to control subsequent waves and ultimately succumb to their infection unlike wild type (WT) C57BL6 mice which are relatively resistant. Although infected Bam32-/- mice had significantly higher hepatomegaly and splenomegaly, their serum AST and ALT levels were not different, suggesting that increased liver pathology may not be responsible for the increased susceptibility of Bam32-/- mice to T. congolense. Using direct ex vivo flow cytometry and ELISA, we show that CD4+ T cells from infected Bam32-/- mice produced significantly increased amounts of disease-exacerbating proinflammatory cytokines (including IFN-γ, TNF-α and IL-6). However, the percentages of regulatory T cells and IL-10-producing CD4+ cells were similar in infected WT and Bam32-/- mice. While serum levels of parasite-specific IgM antibodies were normal, the levels of parasite-specific IgG, (particularly IgG1 and IgG2a) were significantly lower in Bam32-/- mice throughout infection. This was associated with impaired germinal centre response in Bam32-/- mice despite increased numbers of T follicular helper (Tfh) cells. Adoptive transfer studies indicate that intrinsic B cell defect was responsible for the enhanced susceptibility of Bam32-/- mice to T. congolense infection. Conclusions/Significance Collectively, our data show that Bam32 is important for optimal anti-trypanosome IgG antibody response and suppression of disease-promoting proinflammatory cytokines

  9. Space-borne Observations of Atmospheric Pre-Earthquake Signals in Seismically Active Areas: Case Study for Greece 2008-2009

    NASA Technical Reports Server (NTRS)

    Ouzounov, D. P.; Pulinets, S. A.; Davidenko, D. A.; Kafatos, M.; Taylor, P. T.

    2013-01-01

    We are conducting theoretical studies and practical validation of atm osphere/ionosphere phenomena preceding major earthquakes. Our approach is based on monitoring of two physical parameters from space: outgoi ng long-wavelength radiation (OLR) on the top of the atmosphere and e lectron and electron density variations in the ionosphere via GPS Tot al Electron Content (GPS/TEC). We retrospectively analyzed the temporal and spatial variations of OLR an GPS/TEC parameters characterizing the state of the atmosphere and ionosphere several days before four m ajor earthquakes (M>6) in Greece for 2008-2009: M6.9 of 02.12.08, M6. 2 02.20.08; M6.4 of 06.08.08 and M6.4 of 07.01.09.We found anomalous behavior before all of these events (over land and sea) over regions o f maximum stress. We expect that our analysis reveal the underlying p hysics of pre-earthquake signals associated with some of the largest earthquakes in Greece.

  10. Earthquakes - Volcanoes (Causes and Forecast)

    NASA Astrophysics Data System (ADS)

    Tsiapas, E.

    2009-04-01

    EARTHQUAKES - VOLCANOES (CAUSES AND FORECAST) ELIAS TSIAPAS RESEARCHER NEA STYRA, EVIA,GREECE TEL.0302224041057 tsiapas@hol.gr The earthquakes are caused by large quantities of liquids (e.g. H2O, H2S, SO2, ect.) moving through lithosphere and pyrosphere (MOHO discontinuity) till they meet projections (mountains negative projections or projections coming from sinking lithosphere). The liquids are moved from West Eastward carried away by the pyrosphere because of differential speed of rotation of the pyrosphere by the lithosphere. With starting point an earthquake which was noticed at an area and from statistical studies, we know when, where and what rate an earthquake may be, which earthquake is caused by the same quantity of liquids, at the next east region. The forecast of an earthquake ceases to be valid if these components meet a crack in the lithosphere (e.g. limits of lithosphere plates) or a volcano crater. In this case the liquids come out into the atmosphere by the form of gasses carrying small quantities of lava with them (volcano explosion).

  11. Building with Earthquakes in Mind

    NASA Astrophysics Data System (ADS)

    Mangieri, Nicholas

    2016-04-01

    Earthquakes are some of the most elusive and destructive disasters humans interact with on this planet. Engineering structures to withstand earthquake shaking is critical to ensure minimal loss of life and property. However, the majority of buildings today in non-traditional earthquake prone areas are not built to withstand this devastating force. Understanding basic earthquake engineering principles and the effect of limited resources helps students grasp the challenge that lies ahead. The solution can be found in retrofitting existing buildings with proper reinforcements and designs to deal with this deadly disaster. The students were challenged in this project to construct a basic structure, using limited resources, that could withstand a simulated tremor through the use of an earthquake shake table. Groups of students had to work together to creatively manage their resources and ideas to design the most feasible and realistic type of building. This activity provided a wealth of opportunities for the students to learn more about a type of disaster they do not experience in this part of the country. Due to the fact that most buildings in New York City were not designed to withstand earthquake shaking, the students were able to gain an appreciation for how difficult it would be to prepare every structure in the city for this type of event.

  12. Earthquake history of the United States

    USGS Publications Warehouse

    Coffman, Jerry L.; Von Hake, Carl A.; Stover, Carl W.; Coffman, Jerry L.; von Hake, Carl A.; Stover, Carl W.

    1982-01-01

    This publication is a history of the prominent earthquakes in the United States from historical times through 1970. It supersedes all previous editions with the same or similar titles (see page ii) and, in addition to updating earthquake listings through 1970, contains several additions and corrections to previous issues. It also brings together under a common cover earthquake data previously listed in two separate reports: Earthquake History of the United States, Part I, Stronger Earthquakes of the United States (Exclusive of California and Western Nevada) and Earthquake History of the United States, Part II, Stronger Earthquakes of California and Western Nevada. Another addition to this publication is the inclusion of a section describing earthquakes in the Puerto Rico region. For the purpose of listing and describing earthquakes, the United States has been divided into nine regions: (1) Northeastern Region, which includes New England and New York activity and observations of the principal earthquakes of eastern Canada; (2) Eastern Region, including the central Appalachian seismic region activity and the area near Charleston, S.C.; (3) Central Region, which consists of the area between the region just described and the Rocky Mountains; (4) Western Mountain Region, which includes all remaining states except those on the Pacific coast; (5) Washington and Oregon; (6) Alaska; (7) Hawaii; (8) Puerto Rico; and (9) California and Western Nevada. This arrangement has been made chiefly with reference to the natural seismic divisions. It also is a convenient arrangement because there are only three states where there is an important division of earthquake activity: In Tennessee, there are quite distinct areas at opposite ends of the state that fall into different regions. Only central and eastern Nevada are included in the Western Mountain Region, as the activity of the western part is closely associated with that of California. Some earthquake activity has occurred in the

  13. Earthquake preparedness levels amongst youth and adults in Oakland, California

    NASA Astrophysics Data System (ADS)

    Burris, M.; Arroyo-Ruiz, D.; Crockett, C.; Dixon, G.; Jones, M.; Lei, P.; Phillips, B.; Romero, D.; Scott, M.; Spears, D.; Tate, L.; Whitlock, J.; Diaz, J.; Chagolla, R.

    2011-12-01

    The San Francisco Bay Area has not experienced a large earthquake since 1989. However research shows that the Hayward fault is overdue for a tremor, based on paleo-seismic research. To analyze the level of earthquake preparedness in the Oakland area (close to the Hayward fault), we surveyed over 150 people to assess their understanding of earthquakes. Our research evaluates whether increased earthquake knowledge impacts people's preparedness and concern toward earthquake events. Data was collected using smart-phone technology and survey software in four sites across Oakland including; North Oakland, Downtown, East Oakland, and a summer school program in East Oakland, which has youth from throughout the city. Preliminary studies show that over 60% of interviewees have sufficient earthquake knowledge, but that over half of all interviewees are not prepared for a seismic event. Our study shows that in Oakland, California earthquake preparedness levels vary, which could mean we need to develop more ways to disseminate information on earthquake preparedness.

  14. An evaluation of the seismic- window theory for earthquake prediction.

    USGS Publications Warehouse

    McNutt, M.; Heaton, T.H.

    1981-01-01

    Reports studies designed to determine whether earthquakes in the San Francisco Bay area respond to a fortnightly fluctuation in tidal amplitude. It does not appear that the tide is capable of triggering earthquakes, and in particular the seismic window theory fails as a relevant method of earthquake prediction. -J.Clayton

  15. Delayed increase in male suicide rates in tsunami disaster-stricken areas following the great east japan earthquake: a three-year follow-up study in Miyagi Prefecture.

    PubMed

    Orui, Masatsugu; Sato, Yasuhiro; Tazaki, Kanako; Kawamura, Ikuko; Harada, Shuichiro; Hayashi, Mizuho

    2015-01-01

    Devastating natural disasters and their aftermath are known to cause psychological distress. However, little information is available regarding suicide rates following tsunami disasters that destroy regional social services and networks. The aim of the present study was to determine whether the tsunami disaster following the Great East Japan Earthquake in March 2011 has influenced suicide rates. The study period was from March 2009 to February 2014. Tsunami disaster-stricken areas were defined as the 16 municipalities facing the Pacific Ocean in Miyagi Prefecture. Inland areas were defined as other municipalities in Miyagi that were damaged by the earthquake. Suicide rates in the tsunami disaster-stricken areas were compared to national averages, using a time-series analysis and the Poisson distribution test. In tsunami disaster-stricken areas, male suicide rates were significantly lower than the national average during the initial post-disaster period and began to increase after two years. Likewise, male suicide rates in the inland areas decreased for seven months, and then increased to exceed the national average. In contrast, female post-disaster suicide rates did not change in both areas compared to the national average. Importantly, the male suicide rates in the inland areas started to increase earlier compared to the tsunami-stricken areas, which may reflect the relative deficiency of mental healthcare services in the inland areas. Considering the present status that many survivors from the tsunami disaster still live in temporary housing and face various challenges to rebuild their lives, we should continue intensive, long-term mental healthcare services in the tsunami-stricken areas.

  16. Delayed increase in male suicide rates in tsunami disaster-stricken areas following the great east japan earthquake: a three-year follow-up study in Miyagi Prefecture.

    PubMed

    Orui, Masatsugu; Sato, Yasuhiro; Tazaki, Kanako; Kawamura, Ikuko; Harada, Shuichiro; Hayashi, Mizuho

    2015-01-01

    Devastating natural disasters and their aftermath are known to cause psychological distress. However, little information is available regarding suicide rates following tsunami disasters that destroy regional social services and networks. The aim of the present study was to determine whether the tsunami disaster following the Great East Japan Earthquake in March 2011 has influenced suicide rates. The study period was from March 2009 to February 2014. Tsunami disaster-stricken areas were defined as the 16 municipalities facing the Pacific Ocean in Miyagi Prefecture. Inland areas were defined as other municipalities in Miyagi that were damaged by the earthquake. Suicide rates in the tsunami disaster-stricken areas were compared to national averages, using a time-series analysis and the Poisson distribution test. In tsunami disaster-stricken areas, male suicide rates were significantly lower than the national average during the initial post-disaster period and began to increase after two years. Likewise, male suicide rates in the inland areas decreased for seven months, and then increased to exceed the national average. In contrast, female post-disaster suicide rates did not change in both areas compared to the national average. Importantly, the male suicide rates in the inland areas started to increase earlier compared to the tsunami-stricken areas, which may reflect the relative deficiency of mental healthcare services in the inland areas. Considering the present status that many survivors from the tsunami disaster still live in temporary housing and face various challenges to rebuild their lives, we should continue intensive, long-term mental healthcare services in the tsunami-stricken areas. PMID:25765170

  17. Geologic evidence for recurrent moderate to large earthquakes near Charleston, South Carolina

    USGS Publications Warehouse

    Obermeier, S.F.; Gohn, G.S.; Weems, R.E.; Gelinas, R.L.; Rubin, M.

    1985-01-01

    Multiple generations of earthquake-induced sand blows in Quaternary sediments and soils near Charleston, South Carolina, are evidence of recurrent moderate to large earthquakes in that area. The large 1886 earthquake, the only historic earthquake known to have produced sand blows at Charleston, probably caused the youngest observed blows. Older (late Quaternary) sand blows in the Charleston area indicate at least two prehistoric earthquakes with shaking severities comparable to the 1886 event.

  18. A smartphone application for earthquakes that matter!

    NASA Astrophysics Data System (ADS)

    Bossu, Rémy; Etivant, Caroline; Roussel, Fréderic; Mazet-Roux, Gilles; Steed, Robert

    2014-05-01

    Smartphone applications have swiftly become one of the most popular tools for rapid reception of earthquake information for the public, some of them having been downloaded more than 1 million times! The advantages are obvious: wherever someone's own location is, they can be automatically informed when an earthquake has struck. Just by setting a magnitude threshold and an area of interest, there is no longer the need to browse the internet as the information reaches you automatically and instantaneously! One question remains: are the provided earthquake notifications always relevant for the public? What are the earthquakes that really matters to laypeople? One clue may be derived from some newspaper reports that show that a while after damaging earthquakes many eyewitnesses scrap the application they installed just after the mainshock. Why? Because either the magnitude threshold is set too high and many felt earthquakes are missed, or it is set too low and the majority of the notifications are related to unfelt earthquakes thereby only increasing anxiety among the population at each new update. Felt and damaging earthquakes are the ones that matter the most for the public (and authorities). They are the ones of societal importance even when of small magnitude. A smartphone application developed by EMSC (Euro-Med Seismological Centre) with the financial support of the Fondation MAIF aims at providing suitable notifications for earthquakes by collating different information threads covering tsunamigenic, potentially damaging and felt earthquakes. Tsunamigenic earthquakes are considered here to be those ones that are the subject of alert or information messages from the PTWC (Pacific Tsunami Warning Centre). While potentially damaging earthquakes are identified through an automated system called EQIA (Earthquake Qualitative Impact Assessment) developed and operated at EMSC. This rapidly assesses earthquake impact by comparing the population exposed to each expected

  19. EARTHQUAKE HAZARDS IN THE OFFSHORE ENVIRONMENT.

    USGS Publications Warehouse

    Page, Robert A.; Basham, Peter W.

    1985-01-01

    This report discusses earthquake effects and potential hazards in the marine environment, describes and illustrates methods for the evaluation of earthquake hazards, and briefly reviews strategies for mitigating hazards. The report is broadly directed toward engineers, scientists, and others engaged in developing offshore resources. The continental shelves have become a major frontier in the search for new petroleum resources. Much of the current exploration is in areas of moderate to high earthquake activity. If the resources in these areas are to be developed economically and safely, potential earthquake hazards must be identified and mitigated both in planning and regulating activities and in designing, constructing, and operating facilities. Geologic earthquake effects that can be hazardous to marine facilities and operations include surface faulting, tectonic uplift and subsidence, seismic shaking, sea-floor failures, turbidity currents, and tsunamis.

  20. Facts relating to Well No. 5, Lease OCS-P 0234, Pitas Point Unit area, and the earthquake of August 13, 1978, Santa Barbara Channel, California

    USGS Publications Warehouse

    Wayland, Russell G.; Acuff, A. Dewey; McCulloh, Thane M.; Raleigh, C. Barry; Vedder, John G.; Yenne, Keith A.

    1978-01-01

    A build-up of pressures developed in an exploratory well being drilled in the Santa Barbara Channel during the period August 9 to 15, 1978. Nearly coincidentally, a sharp earthquake occurred 2 miles south of the city of Santa Barbara at 3:55 p.m. PDT on August 13, 1978. A task group was formed by the Director, Geological Survey, on August 14, mainly because of concern over the high down-hole pressures in the well. The charge to the task group was to study the situation fully in order that appropriate and immediate measures could be directed to protect against a fracturing of rock formations in the vicinity of the hole that might permit the escape of gas or oil to the surface. The task group was also asked to look into the possibility of any relationship between the well problems and the earthquake.

  1. A Large Scale Automatic Earthquake Location Catalog in the San Jacinto Fault Zone Area Using An Improved Shear-Wave Detection Algorithm

    NASA Astrophysics Data System (ADS)

    White, M. C. A.; Ross, Z.; Vernon, F.; Ben-Zion, Y.

    2015-12-01

    UC San Diego's ANZA network began archiving event-triggered data in 1982. As a result of improved recording technology, continuous waveform data archives are available starting in 1998. This continuous dataset, from 1998-present, represents a wealth of potential insight into spatio-temporal seismicity patterns, earthquake physics and mechanics of the San Jacinto Fault Zone. However, the volume of data renders manual analysis costly. In order to investigate the characteristics of the data in space and time, an automatic earthquake location catalog is needed. To this end, we apply standard earthquake signal processing techniques to the continuous data to detect first-arriving P-waves in combination with a recently developed S-wave detection algorithm. The resulting dataset of arrival time observations are processed using a grid association algorithm to produce initial absolute locations which are refined using a location inversion method that accounts for 3-D velocity heterogeneities. Precise relative locations are then derived from the refined absolute locations using the HypoDD double-difference algorithm. Moment magnitudes for the events are estimated from multi-taper spectral analysis. A >650% increase in the S:P pick ratio is achieved using the updated S-wave detection algorithm, when compared to the currently available catalog for the ANZA network. The increased number of S-wave observations leads to improved earthquake location accuracy and reliability (ie. less false event detections). Various aspects of spatio-temporal seismicity patterns and size distributions are investigated. Updated results will be presented at the meeting.

  2. Degradation of trace concentrations of the persistent groundwater pollutant 2,6-dichlorobenzamide (BAM) in bioaugmented rapid sand filters.

    PubMed

    Albers, Christian Nyrop; Feld, Louise; Ellegaard-Jensen, Lea; Aamand, Jens

    2015-10-15

    Groundwater is an important drinking water resource. Yet, this resource is threatened by pollution from chemicals, such as pesticides and their degradation products. To investigate the potential for remediation of groundwater polluted by trace concentrations of the pesticide residue 2,6-dichlorobenzamide (BAM), we established a pilot waterworks including two sand filters. The waterworks treated groundwater polluted with 0.2 μg/L BAM at flow conditions typical for rapid sand filters. Bioaugmentation of the sand filter with a specific BAM-degrading bacterium (Aminobacter sp. MSH1) resulted in significant BAM degradation to concentrations below the legal threshold level (0.1 μg/L), and this without adverse effects on other sand filter processes such as ammonium and iron oxidation. However, efficient degradation for more than 2-3 weeks was difficult to maintain due to loss of MSH1-bacteria, especially during backwashing. By limiting backwash procedures, the period of degradation was prolonged, but bacteria (and hence degradation activity) were still lost with time. Protozoa were observed to grow in the filters to a density that contributed significantly to the general loss of bacteria from the filters. Additionally, the concentration of easily assimilable organic carbon (AOC) in the remediated water may have been too low to sustain a sufficient population of degrader bacteria in the filter. This study shows that scaling up is not trivial and shortcomings in transferring degradation rates obtained in batch experiments to a rapid sand filter system are discussed. Further optimization is necessary to obtain and control more temporally stable systems for water purification. However, for the first time outside the laboratory and at realistic conditions a potential for the biodegradation of recalcitrant micropollutants in bioaugmented rapid sand filters is shown.

  3. Degradation of trace concentrations of the persistent groundwater pollutant 2,6-dichlorobenzamide (BAM) in bioaugmented rapid sand filters.

    PubMed

    Albers, Christian Nyrop; Feld, Louise; Ellegaard-Jensen, Lea; Aamand, Jens

    2015-10-15

    Groundwater is an important drinking water resource. Yet, this resource is threatened by pollution from chemicals, such as pesticides and their degradation products. To investigate the potential for remediation of groundwater polluted by trace concentrations of the pesticide residue 2,6-dichlorobenzamide (BAM), we established a pilot waterworks including two sand filters. The waterworks treated groundwater polluted with 0.2 μg/L BAM at flow conditions typical for rapid sand filters. Bioaugmentation of the sand filter with a specific BAM-degrading bacterium (Aminobacter sp. MSH1) resulted in significant BAM degradation to concentrations below the legal threshold level (0.1 μg/L), and this without adverse effects on other sand filter processes such as ammonium and iron oxidation. However, efficient degradation for more than 2-3 weeks was difficult to maintain due to loss of MSH1-bacteria, especially during backwashing. By limiting backwash procedures, the period of degradation was prolonged, but bacteria (and hence degradation activity) were still lost with time. Protozoa were observed to grow in the filters to a density that contributed significantly to the general loss of bacteria from the filters. Additionally, the concentration of easily assimilable organic carbon (AOC) in the remediated water may have been too low to sustain a sufficient population of degrader bacteria in the filter. This study shows that scaling up is not trivial and shortcomings in transferring degradation rates obtained in batch experiments to a rapid sand filter system are discussed. Further optimization is necessary to obtain and control more temporally stable systems for water purification. However, for the first time outside the laboratory and at realistic conditions a potential for the biodegradation of recalcitrant micropollutants in bioaugmented rapid sand filters is shown. PMID:26125500

  4. Post-traumatic stress disorder, anxiety and depression among the elderly: a survey of the hard-hit areas a year after the Wenchuan earthquake.

    PubMed

    Zhang, Zhen; Shi, Zhanbiao; Wang, Li; Liu, Mingxin

    2012-02-01

    Few studies to date have examined psychological sequelae of natural disasters among the elderly in China. The aim of this study was to investigate the prevalence rates of probable post-traumatic stress disorder (PTSD), anxiety and depression in the elderly survivors a year after the Wenchuan earthquake as well as to analyse related risk factors. The community-based sample of the study consisted of 284 elderly survivors (≥60 years). PTSD was assessed by the PTSD Checklist--Civilian version, and anxiety and depression were assessed by the Hopkins Symptoms Checklist. In total, the estimated prevalence rates of probable PTSD, anxiety and depression were 26.3%, 42.9% and 35.2%, respectively. Nearly a fifth of the elderly participants reported symptoms that meet the criteria for all three of these mental disorders. Results indicated that some factors associated with earthquake-exposure intensity, which included loss of livelihood, bereavement, injury and initial fear during the earthquake, were among the significant risk factors for these mental disorders. Women had a higher risk of suffering from probable anxiety as compared to men. Finally, the significance and limitations of this study were also discussed.

  5. Issues on the Japanese Earthquake Hazard Evaluation

    NASA Astrophysics Data System (ADS)

    Hashimoto, M.; Fukushima, Y.; Sagiya, T.

    2013-12-01

    The 2011 Great East Japan Earthquake forced the policy of counter-measurements to earthquake disasters, including earthquake hazard evaluations, to be changed in Japan. Before the March 11, Japanese earthquake hazard evaluation was based on the history of earthquakes that repeatedly occurs and the characteristic earthquake model. The source region of an earthquake was identified and its occurrence history was revealed. Then the conditional probability was estimated using the renewal model. However, the Japanese authorities changed the policy after the megathrust earthquake in 2011 such that the largest earthquake in a specific seismic zone should be assumed on the basis of available scientific knowledge. According to this policy, three important reports were issued during these two years. First, the Central Disaster Management Council issued a new estimate of damages by a hypothetical Mw9 earthquake along the Nankai trough during 2011 and 2012. The model predicts a 34 m high tsunami on the southern Shikoku coast and intensity 6 or higher on the JMA scale in most area of Southwest Japan as the maximum. Next, the Earthquake Research Council revised the long-term earthquake hazard evaluation of earthquakes along the Nankai trough in May 2013, which discarded the characteristic earthquake model and put much emphasis on the diversity of earthquakes. The so-called 'Tokai' earthquake was negated in this evaluation. Finally, another report by the CDMC concluded that, with the current knowledge, it is hard to predict the occurrence of large earthquakes along the Nankai trough using the present techniques, based on the diversity of earthquake phenomena. These reports created sensations throughout the country and local governments are struggling to prepare counter-measurements. These reports commented on large uncertainty in their evaluation near their ends, but are these messages transmitted properly to the public? Earthquake scientists, including authors, are involved in

  6. EBNA-2 transactivates a lymphoid-specific enhancer in the BamHI C promoter of Epstein-Barr virus.

    PubMed Central

    Sung, N S; Kenney, S; Gutsch, D; Pagano, J S

    1991-01-01

    Among the few Epstein-Barr virus (EBV) genes expressed during latency are the Epstein-Barr nuclear antigens (EBNAs), at least one of which contributes to the ability of the virus to transform B lymphocytes. We have analyzed a promoter located in the BamHI-C fragment of EBV which is responsible for the expression of EBNA-1 in some cell lines. Deletion analysis of a 1.4-kb region 5' of the RNA start site has identified a 700-bp fragment that is required for optimal promoter activity in latently infected B lymphocytes, as shown by promoter constructs linked to the chloramphenicol acetyltransferase reporter gene. This fragment is also able to enhance activity, in an orientation-independent manner, of the simian virus 40 early promoter linked to the chloramphenicol acetyltransferase gene. The enhancer element has some constitutive activity in EBV-negative lymphoid cells, which is increased in the presence of the EBNA-2 gene product. Further deletions have shown that the EBNA-2-responsive region requires a 98-bp region that contains a degenerate octamer-binding motif. In epithelial cells there was no enhancer activity regardless of the presence of EBNA-2. These results demonstrate that BamHI-C promoter activity may be dependent not on an enhancer contained in the ori-P, as was previously assumed, but rather on EBNA-2 transactivation of this more proximal enhancer located in the upstream region of the BamHI C promoter itself. Images PMID:1850003

  7. Outer membrane β-barrel protein folding is physically controlled by periplasmic lipid head groups and BamA.

    PubMed

    Gessmann, Dennis; Chung, Yong Hee; Danoff, Emily J; Plummer, Ashlee M; Sandlin, Clifford W; Zaccai, Nathan R; Fleming, Karen G

    2014-04-22

    Outer membrane β-barrel proteins (OMPs) are crucial for numerous cellular processes in prokaryotes and eukaryotes. Despite extensive studies on OMP biogenesis, it is unclear why OMPs require assembly machineries to fold into their native outer membranes, as they are capable of folding quickly and efficiently through an intrinsic folding pathway in vitro. By investigating the folding of several bacterial OMPs using membranes with naturally occurring Escherichia coli lipids, we show that phosphoethanolamine and phosphoglycerol head groups impose a kinetic barrier to OMP folding. The kinetic retardation of OMP folding places a strong negative pressure against spontaneous incorporation of OMPs into inner bacterial membranes, which would dissipate the proton motive force and undoubtedly kill bacteria. We further show that prefolded β-barrel assembly machinery subunit A (BamA), the evolutionarily conserved, central subunit of the BAM complex, accelerates OMP folding by lowering the kinetic barrier imposed by phosphoethanolamine head groups. Our results suggest that OMP assembly machineries are required in vivo to enable physical control over the spontaneously occurring OMP folding reaction in the periplasm. Mechanistic studies further allowed us to derive a model for BamA function, which explains how OMP assembly can be conserved between prokaryotes and eukaryotes.

  8. Outer membrane β-barrel protein folding is physically controlled by periplasmic lipid head groups and BamA

    PubMed Central

    Gessmann, Dennis; Chung, Yong Hee; Danoff, Emily J.; Plummer, Ashlee M.; Sandlin, Clifford W.; Zaccai, Nathan R.; Fleming, Karen G.

    2014-01-01

    Outer membrane β-barrel proteins (OMPs) are crucial for numerous cellular processes in prokaryotes and eukaryotes. Despite extensive studies on OMP biogenesis, it is unclear why OMPs require assembly machineries to fold into their native outer membranes, as they are capable of folding quickly and efficiently through an intrinsic folding pathway in vitro. By investigating the folding of several bacterial OMPs using membranes with naturally occurring Escherichia coli lipids, we show that phosphoethanolamine and phosphoglycerol head groups impose a kinetic barrier to OMP folding. The kinetic retardation of OMP folding places a strong negative pressure against spontaneous incorporation of OMPs into inner bacterial membranes, which would dissipate the proton motive force and undoubtedly kill bacteria. We further show that prefolded β-barrel assembly machinery subunit A (BamA), the evolutionarily conserved, central subunit of the BAM complex, accelerates OMP folding by lowering the kinetic barrier imposed by phosphoethanolamine head groups. Our results suggest that OMP assembly machineries are required in vivo to enable physical control over the spontaneously occurring OMP folding reaction in the periplasm. Mechanistic studies further allowed us to derive a model for BamA function, which explains how OMP assembly can be conserved between prokaryotes and eukaryotes. PMID:24715731

  9. H3K36 Trimethylation-Mediated Epigenetic Regulation is Activated by Bam and Promotes Germ Cell Differentiation During Early Oogenesis in Drosophila.

    PubMed

    Mukai, Masanori; Hira, Seiji; Nakamura, Katsuhiro; Nakamura, Shoichi; Kimura, Hiroshi; Sato, Masanao; Kobayashi, Satoru

    2015-01-01

    Epigenetic silencing is critical for maintaining germline stem cells in Drosophila ovaries. However, it remains unclear how the differentiation factor, Bag-of-marbles (Bam), counteracts transcriptional silencing. We found that the trimethylation of lysine 36 on histone H3 (H3K36me3), a modification that is associated with gene activation, is enhanced in Bam-expressing cells. H3K36me3 levels were reduced in flies deficient in Bam. Inactivation of the Set2 methyltransferase, which confers the H3K36me3 modification, in germline cells markedly reduced H3K36me3 and impaired differentiation. Genetic analyses revealed that Set2 acts downstream of Bam. Furthermore, orb expression, which is required for germ cell differentiation, was activated by Set2, probably through direct H3K36me3 modification of the orb locus. Our data indicate that H3K36me3-mediated epigenetic regulation is activated by bam, and that this modification facilitates germ cell differentiation, probably through transcriptional activation. This work provides a novel link between Bam and epigenetic transcriptional control. PMID:25572421

  10. Earthquakes May-June 1980.

    USGS Publications Warehouse

    Person, W.J.

    1981-01-01

    The months were seismically active, although only one major event (7.0-7.9) occurred in an unpopulated Philippine Island. Mexico was struck by a 6.3 quake on June 9 killing at least two people. The most significant earthquake in the United States was in the Mammoth Lakes area of California. -from Author

  11. Mineralization of the Common Groundwater Pollutant 2,6-Dichlorobenzamide (BAM) and its Metabolite 2,6-Dichlorobenzoic Acid (2,6-DCBA) in Sand Filter Units of Drinking Water Treatment Plants.

    PubMed

    Vandermaesen, Johanna; Horemans, Benjamin; Degryse, Julie; Boonen, Jos; Walravens, Eddy; Springael, Dirk

    2016-09-20

    The intrinsic capacity to mineralize the groundwater pollutant 2,6-dichlorobenzamide (BAM) and its metabolite 2,6-dichlorobenzoic acid (2,6-DCBA) was evaluated in samples from sand filters (SFs) of drinking water treatment plants (DWTPs). Whereas BAM mineralization occurred rarely and only in SFs exposed to BAM, 2,6-DCBA mineralization was common in SFs, including those treating uncontaminated water. Nevertheless, SFs treating BAM contaminated water showed the highest 2,6-DCBA mineralization rates. For comparison, 2,6-DCBA and BAM mineralization were determined in various topsoil samples. As in SF samples, BAM mineralization was rare, whereas 2,6-DCBA mineralization capacity appeared widespread, with high mineralization rates found especially in forest soils. Multivariate analysis showed that in both SF and soil samples, high 2,6-DCBA mineralization correlated with high organic carbon content. Adding a 2,6-DCBA degradation deficient mutant of the BAM mineralizing Aminobacter sp. MSH1 confirmed that 2,6-DCBA produced from BAM is rapidly mineralized by the endogenous microbial community in SFs showing intrinsic 2,6-DCBA mineralization. This study demonstrates that (i) 2,6-DCBA mineralization is widely established in SFs of DWTPs, allowing the mineralization of 2,6-DCBA produced during BAM degradation and (ii) the first metabolic step in BAM mineralization is rare in microbial communities, rather than its further degradation beyond 2,6-DCBA. PMID:27533590

  12. Earthquakes triggered by fluid extraction

    NASA Astrophysics Data System (ADS)

    Segall, P.

    1989-10-01

    Seismicity is correlated in space and time with production from some oil and gas fields where pore pressures have declined by several tens of megapascals. Reverse faulting has occurred both above and below petroleum reservoirs, and normal faulting has occurred on the flanks of at least one reservoir. The theory of poroelasticity requires that fluid extraction locally alter the state of stress. Calculations with simple geometries predict stress perturbations that are consistent with observed earthquake locations and focal mechanisms. Measurements of surface displacement and strain, pore pressure, stress, and poroelastic rock properties in such areas could be used to test theoretical predictions and improve our understanding of earthquake mechanics.

  13. Earthquakes triggered by fluid extraction

    USGS Publications Warehouse

    Segall, P.

    1989-01-01

    Seismicity is correlated in space and time with production from some oil and gas fields where pore pressures have declined by several tens of megapascals. Reverse faulting has occurred both above and below petroleum reservoirs, and normal faulting has occurred on the flanks of at least one reservoir. The theory of poroelasticity requires that fluid extraction locally alter the state of stress. Calculations with simple geometries predict stress perturbations that are consistent with observed earthquake locations and focal mechanisms. Measurements of surface displacement and strain, pore pressure, stress, and poroelastic rock properties in such areas could be used to test theoretical predictions and improve our understanding of earthquake mechanics. -Author

  14. Low stress drop earthquakes in the rupture zone of the 1992 Nicaragua tsunami earthquake

    NASA Astrophysics Data System (ADS)

    Bilek, Susan L.; Rotman, Holly M. M.; Phillips, W. Scott

    2016-10-01

    Tsunami earthquakes, events that generate larger than expected tsunami and are deficient in high-frequency seismic radiation, are rare but hazardous to coastal populations. One model for these events is shallow rupture through low-strength materials. We calculate seismic moment, corner frequency, and stress drop for 216 earthquakes (2.1 < Mw < 4.7, November 2005 to June 2006) within and external to the 1992 Nicaragua tsunami earthquake rupture zone to test the hypothesis that differences in fault zone properties defined the limits of the 1992 tsunami rupture zone and continue to produce spatial variations in earthquake source properties. Mean stress drop of events within the rupture area is 1.2 MPa, and 5.5 MPa for events just outside of the rupture zone, with similar magnitude earthquakes in each group. Our results demonstrate different source parameter characteristics for microseismicity in the region of a past tsunami earthquake.

  15. Possible occurrence of a giant interplate earthquake in northeast Japan greater than the 2011 Tohoku earthquake

    NASA Astrophysics Data System (ADS)

    Ohtani, M.; Hirahara, K.; Hori, T.; Hyodo, M.

    2012-12-01

    We supposed there occur M7-class earthquakes and the co-rupturing M8 earthquakes on the Pacific plate interface subducting beneath northeast Japan. Against our speculation, the 2011 Tohoku earthquake grew up to Mw9.0. We have so far constructed cycle models of this giant earthquake to understand why this grew up to Mw9.0. Next question is; is there any possibility that a much larger earthquake occurs in this region? In this study, we explore this possibility through quasi-dynamic earthquake cycle simulations. The 2011 Tohoku earthquake ruptured a large region of 200km x 500km. The rupture region includes a confined area with huge coseismic slip over 50 m in the shallow Off-Miyagi region close to the Japan Trench, and several M7 asperities in Off-Miyagi and Ibaraki regions which have been ruptured repeatedly at intervals of several ten years. The tsunami deposit surveys suggest this giant earthquake has the recurrence time of several hundred years. The afterslip occurs mainly in the deeper region of the coseismic slip region, except the Off-Miyagi region [Ozawa et al., 2012]. At Off-Kamaishi and Off-Fukushima regions located in the northern and southern sides of the Off-Miyagi region, we can find the local maximum of the afterslip. The Off-Kamaishi region did not produce much coseismic slip, and has not experienced historical large earthquakes. And no large afterslip extended to the northern region beyond Off-Kamaishi. Then, the Off-Kamaishi region is a kind of boundary between the 2011 Tohoku earthquake and its adjacent northern regions. In the northern region, there occurred the 1968 Off-Tokachi Mw8.3 earthquake, which has three M7 asperities with recurrence times of several ten years [Yamanaka & Kikuchi, 2004]. An aftershock of the 2011 Tohoku earthquake, which occurred 22 minutes after the main shock, is located at the southern asperity area. And there is a region close to the Japan Trench, where the 1897 Meiji-sanriku tsunami earthquake occurred. We performed

  16. Earthquake Scaling Relations

    NASA Astrophysics Data System (ADS)

    Jordan, T. H.; Boettcher, M.; Richardson, E.

    2002-12-01

    Using scaling relations to understand nonlinear geosystems has been an enduring theme of Don Turcotte's research. In particular, his studies of scaling in active fault systems have led to a series of insights about the underlying physics of earthquakes. This presentation will review some recent progress in developing scaling relations for several key aspects of earthquake behavior, including the inner and outer scales of dynamic fault rupture and the energetics of the rupture process. The proximate observations of mining-induced, friction-controlled events obtained from in-mine seismic networks have revealed a lower seismicity cutoff at a seismic moment Mmin near 109 Nm and a corresponding upper frequency cutoff near 200 Hz, which we interpret in terms of a critical slip distance for frictional drop of about 10-4 m. Above this cutoff, the apparent stress scales as M1/6 up to magnitudes of 4-5, consistent with other near-source studies in this magnitude range (see special session S07, this meeting). Such a relationship suggests a damage model in which apparent fracture energy scales with the stress intensity factor at the crack tip. Under the assumption of constant stress drop, this model implies an increase in rupture velocity with seismic moment, which successfully predicts the observed variation in corner frequency and maximum particle velocity. Global observations of oceanic transform faults (OTFs) allow us to investigate a situation where the outer scale of earthquake size may be controlled by dynamics (as opposed to geologic heterogeneity). The seismicity data imply that the effective area for OTF moment release, AE, depends on the thermal state of the fault but is otherwise independent of fault's average slip rate; i.e., AE ~ AT, where AT is the area above a reference isotherm. The data are consistent with β = 1/2 below an upper cutoff moment Mmax that increases with AT and yield the interesting scaling relation Amax ~ AT1/2. Taken together, the OTF

  17. Intensity earthquake scenario (scenario event - a damaging earthquake with higher probability of occurrence) for the city of Sofia

    NASA Astrophysics Data System (ADS)

    Aleksandrova, Irena; Simeonova, Stela; Solakov, Dimcho; Popova, Maria

    2014-05-01

    Among the many kinds of natural and man-made disasters, earthquakes dominate with regard to their social and economical impact on the urban environment. Global seismic risk to earthquakes are increasing steadily as urbanization and development occupy more areas that a prone to effects of strong earthquakes. Additionally, the uncontrolled growth of mega cities in highly seismic areas around the world is often associated with the construction of seismically unsafe buildings and infrastructures, and undertaken with an insufficient knowledge of the regional seismicity peculiarities and seismic hazard. The assessment of seismic hazard and generation of earthquake scenarios is the first link in the prevention chain and the first step in the evaluation of the seismic risk. The earthquake scenarios are intended as a basic input for developing detailed earthquake damage scenarios for the cities and can be used in earthquake-safe town and infrastructure planning. The city of Sofia is the capital of Bulgaria. It is situated in the centre of the Sofia area that is the most populated (the population is of more than 1.2 mil. inhabitants), industrial and cultural region of Bulgaria that faces considerable earthquake risk. The available historical documents prove the occurrence of destructive earthquakes during the 15th-18th centuries in the Sofia zone. In 19th century the city of Sofia has experienced two strong earthquakes: the 1818 earthquake with epicentral intensity I0=8-9 MSK and the 1858 earthquake with I0=9-10 MSK. During the 20th century the strongest event occurred in the vicinity of the city of Sofia is the 1917 earthquake with MS=5.3 (I0=7-8 MSK). Almost a century later (95 years) an earthquake of moment magnitude 5.6 (I0=7-8 MSK) hit the city of Sofia, on May 22nd, 2012. In the present study as a deterministic scenario event is considered a damaging earthquake with higher probability of occurrence that could affect the city with intensity less than or equal to VIII

  18. Helena banks strike-slip(. ) fault and the relation to other Cenozoic faults along reactivated Triassic(. ) basin boundary fault zones in the Charleston, South Carolina, earthquake area - results from a marine high-resolution multichannel seismic-reflection survey

    SciTech Connect

    Behrendt, J.C.; Yuan, A.

    1985-01-01

    In 1981, the USGS conducted a high-resolution multichannel seismic (MCS) survey offshore of Charleston, South Carolina, to study the relation of Cenozoic faulting to future earthquake hazard. High-angle reverse displacement of Coastal Plain sedimentary rock indicating a linear increase with depth of 51 +/- 12 m/km is observed on the reflection profiles. This is similar to the Gants and Cooke faults in the meizoseismal area of the 1886 Charleston earthquake. The authors interpret these results to indicate that the stress field cannot have varied significantly in direction or in magnitude from Late Cretaceous time to Miocene or Pliocene time in the region. The HBF zone trends N 66/sup 0/ E; it comprises several 15- to 40-km-long segments that trend from N 68/sup 0/ E to N 77/sup 0/ E. The en-echelon pattern of the segments is compatible with left-lateral strike-slip and is thus consistent with the present northeast-trending maximum compressional stress field. The HBF zone appears to be an obliquely compressional reactivation of a tensional Triassic(.) fault zone bounding the Triassic(.) Kiawah Basin that has been identified on several MCS profiles. Similarly, the northeast-trending Gants reverse or strike-slip fault was probably reactivated from an old tensional fault bounding the Jedburg Triassic(.) basin in the 1886 meizoseismal area.

  19. Intraplate triggered earthquakes: Observations and interpretation

    USGS Publications Warehouse

    Hough, S.E.; Seeber, L.; Armbruster, J.G.

    2003-01-01

    We present evidence that at least two of the three 1811-1812 New Madrid, central United States, mainshocks and the 1886 Charleston, South Carolina, earthquake triggered earthquakes at regional distances. In addition to previously published evidence for triggered earthquakes in the northern Kentucky/southern Ohio region in 1812, we present evidence suggesting that triggered events might have occurred in the Wabash Valley, to the south of the New Madrid Seismic Zone, and near Charleston, South Carolina. We also discuss evidence that earthquakes might have been triggered in northern Kentucky within seconds of the passage of surface waves from the 23 January 1812 New Madrid mainshock. After the 1886 Charleston earthquake, accounts suggest that triggered events occurred near Moodus, Connecticut, and in southern Indiana. Notwithstanding the uncertainty associated with analysis of historical accounts, there is evidence that at least three out of the four known Mw 7 earthquakes in the central and eastern United States seem to have triggered earthquakes at distances beyond the typically assumed aftershock zone of 1-2 mainshock fault lengths. We explore the possibility that remotely triggered earthquakes might be common in low-strain-rate regions. We suggest that in a low-strain-rate environment, permanent, nonelastic deformation might play a more important role in stress accumulation than it does in interplate crust. Using a simple model incorporating elastic and anelastic strain release, we show that, for realistic parameter values, faults in intraplate crust remain close to their failure stress for a longer part of the earthquake cycle than do faults in high-strain-rate regions. Our results further suggest that remotely triggered earthquakes occur preferentially in regions of recent and/or future seismic activity, which suggests that faults are at a critical stress state in only some areas. Remotely triggered earthquakes may thus serve as beacons that identify regions of

  20. Landslides and ridge-top failures associated with the epicentral area of the Loma Prieta earthquake of October 17, 1989 Santa Cruz County, California

    SciTech Connect

    Spittler, T.E.; Sydnor, R.H.

    1990-01-01

    Extensive landslides and ridge-top failures occurred in the epicentral are of the Loma Prieta earthquake. These failures have been subdivided into four categories: (1) small rockfalls, dry debris flows, minor slumps, wedge-failure landslides along highway cut-slopes, and sea cliff failures; (2) ridge-top fractures dominated by tensional separation; (3) crown scarps of incipient landslides on the axes of steeply-plunging, steed-sided spur ridges; and (4) remobilized portions of existing large-scale rotational landslide complexes. These failures are described in detail.

  1. EARTHQUAKES - VOLCANOES (Causes - Forecast - Counteraction)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2014-05-01

    going to be, when we know the record of specific earthquakes and the routes they have followed towards the East. For example, to foresee an earthquake in the Mediterranean region, we take starting point earthquakes to Latin America (0°-40°).The aforementioned elements will reach Italy in an average time period of 49 days and Greece in 53 days. The most reliable preceding phenomenon to determine the epicenter of an earthquake is the rise of the crust's temperature at the area where a large quantity of elements is concentrated, among other phenomena that can be detected either by instruments or by our senses. When there is an active volcano along the route between the area where the "starting-point" earthquake occurred and the area where we expect the same elements to cause a new earthquake, it is possible these elements will escape through the volcano's crater, carrying lava with them. We could contribute to that end, nullifying earthquakes that might be triggered by these elements further to the east, by using manmade resources, like adequate quantities of explosives at the right moment.

  2. Earthquakes - Volcanoes (Causes - Forecast - Counteraction)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2013-04-01

    going to be, when we know the record of specific earthquakes and the routes they have followed towards the East. For example, to foresee an earthquake in the Mediterranean region, we take starting point earthquakes to Latin America (0°-40°).The aforementioned elements will reach Italy in an average time period of 49 days and Greece in 53 days. The most reliable preceding phenomenon to determine the epicenter of an earthquake is the rise of the crust's temperature at the area where a large quantity of elements is concentrated, among other phenomena that can be detected either by instruments or by our senses. When there is an active volcano along the route between the area where the "starting-point" earthquake occurred and the area where we expect the same elements to cause a new earthquake, it is possible these elements will escape through the volcano's crater, carrying lava with them. We could contribute to that end, nullifying earthquakes that might be triggered by these elements further to the east, by using manmade resources, like adequate quantities of explosives at the right moment.

  3. Earthquakes - Volcanoes (Causes - Forecast - Counteraction)

    NASA Astrophysics Data System (ADS)

    Tsiapas, Elias

    2015-04-01

    going to be, when we know the record of specific earthquakes and the routes they have followed towards the East. For example, to foresee an earthquake in the Mediterranean region, we take starting point earthquakes to Latin America (0°-40°).The aforementioned elements will reach Italy in an average time period of 49 days and Greece in 53 days. The most reliable preceding phenomenon to determine the epicenter of an earthquake is the rise of the crust's temperature at the area where a large quantity of elements is concentrated, among other phenomena that can be detected either by instruments or by our senses. When there is an active volcano along the route between the area where the "starting-point" earthquake occurred and the area where we expect the same elements to cause a new earthquake, it is possible these elements will escape through the volcano's crater, carrying lava with them. We could contribute to that end, nullifying earthquakes that might be triggered by these elements further to the east, by using manmade resources, like adequate quantities of explosives at the right moment.

  4. Napa Earthquake impact on water systems

    NASA Astrophysics Data System (ADS)

    Wang, J.

    2014-12-01

    South Napa earthquake occurred in Napa, California on August 24 at 3am, local time, and the magnitude is 6.0. The earthquake was the largest in SF Bay Area since the 1989 Loma Prieta earthquake. Economic loss topped $ 1 billion. Wine makers cleaning up and estimated the damage on tourism. Around 15,000 cases of lovely cabernet were pouring into the garden at the Hess Collection. Earthquake potentially raise water pollution risks, could cause water crisis. CA suffered water shortage recent years, and it could be helpful on how to prevent underground/surface water pollution from earthquake. This research gives a clear view on drinking water system in CA, pollution on river systems, as well as estimation on earthquake impact on water supply. The Sacramento-San Joaquin River delta (close to Napa), is the center of the state's water distribution system, delivering fresh water to more than 25 million residents and 3 million acres of farmland. Delta water conveyed through a network of levees is crucial to Southern California. The drought has significantly curtailed water export, and salt water intrusion reduced fresh water outflows. Strong shaking from a nearby earthquake can cause saturated, loose, sandy soils liquefaction, and could potentially damage major delta levee systems near Napa. Napa earthquake is a wake-up call for Southern California. It could potentially damage freshwater supply system.

  5. Impacts of the 1669 eruption and the 1693 earthquakes on the Etna Region (Eastern Sicily, Italy): An example of recovery and response of a small area to extreme events

    NASA Astrophysics Data System (ADS)

    Branca, Stefano; Azzaro, Raffaele; De Beni, Emanuela; Chester, David; Duncan, Angus

    2015-09-01

    In this paper we trace the impact of the 1669 eruption and the 1693 earthquakes in eastern Sicily, their effects on the people living in the Etna region and, more particularly, in the city of Catania and its hinterland. The former event was the largest historic eruption of Etna, having a flow field with an area of ca. 40 km2 and a maximum flow length of ca. 17 km, whereas the latter - occurring only 24 years later - killed between 11,000 and 20,000 of Catania's estimated 20-27,000 inhabitants, plus many more in smaller settlements. Using a combination of field-based research, contemporary accounts and archival sources, the authors are able to draw a number of conclusions. First, the 1669 eruption, although it did not kill or injure, was economically the most devastating of historical eruptions. Although it affected a limited area, inundation by lava meant that land was effectively sterilized for centuries and, in a pre-industrial agriculturally-based economy, recovery could not occur quickly without outside assistance from the State. Indeed some of the worst affected municipalities (i.e. Comuni) were only able to support populations that were much reduced in size. Secondly, much of the damage caused to buildings by volcanic earthquakes was effectively masked, because most of the settlements affected were quickly covered by lava flows. The vulnerability to volcanic earthquakes of traditionally constructed buildings has, however, remained a serious example of un-ameliorated risk exposure through to the present day. A third conclusion is that the 1693 earthquakes, although more serious with respect to the number of people and the area they affected in terms of mortality, morbidity and their immediate economic impact, saw a rapid and sustained recovery. This was due in part to the fact that, in contrast to lava flows, an earthquake does not sterilize land, but more significant was the reduction in population numbers which served both to release and concentrate funds

  6. A Simplified Approach to Earthquake Risk in Mainland China

    NASA Astrophysics Data System (ADS)

    Chen, Qi-Fu; Mi, Hongliang; Huang, Jing

    2005-06-01

    There are limitations in conventional earthquake loss procedures if attempts are made to apply these to assess the social and economic impacts of recent disastrous earthquakes. This paper addresses the need to develop an applicable model for estimating the significant increases of earthquake loss in mainland China. The casualties of earthquakes were studied first. The casualties of earthquakes are strongly related to earthquake strength, occurrence time (day or night) and the distribution of population in the affected area. Using data on earthquake casualties in mainland China from 1980 to 2000, we suggest a relationship between average losses of life and the magnitude of earthquakes. Combined with information on population density and earthquake occurrence times, we use these data to give a further relationship between the loss of life and factors like population density, intensity and occurrence time of the earthquake. Earthquakes that occurred from 2001 to 2003 were tested for the given relationships. This paper also explores the possibility of using a macroeconomic indicator, here GDP (Gross Domestic Product), to roughly estimate earthquake exposure in situations where no detailed insurance or similar inventories exist, thus bypassing some problems of the conventional method.

  7. Accounts describing the Mississippi Valley Earthquakes of 1811-12

    USGS Publications Warehouse

    1987-01-01

    At 2:15 a.m. on December 16, 1811, a unique sequence of earthquakes began in what is today southeast Missouri and northeast Arkansas. Although the area was sparsely populated,the earthquakes, generally referred to as the New Madrid earthquakes, were felt throughout a wide area if the Central and Eastern United States. Consequently, they were widely reported in newspapers and in other written accounts.

  8. Earthquake-caused landslides: a major disturbance to tropical forests.

    PubMed

    Garwood, N C; Janos, D P; Brokaw, N

    1979-09-01

    Earthquakes occasionally denude large areas of tropical forest: for example, 54 square kilometers in Panama in 1976 and 130 square kilometers in New Guinea in 1935. Earthquake rates in New Guinea, but not in Panama, are sufficiently high so that substantial areas of disturbed, nonclimax forest may accumulate. In New Guinea, earthquake-caused landslides are as important as tree falls in the disturbance regime. PMID:17795560

  9. The size of earthquakes

    USGS Publications Warehouse

    Kanamori, H.

    1980-01-01

    How we should measure the size of an earthquake has been historically a very important, as well as a very difficult, seismological problem. For example, figure 1 shows the loss of life caused by earthquakes in recent times and clearly demonstrates that 1976 was the worst year for earthquake casualties in the 20th century. However, the damage caused by an earthquake is due not only to its physical size but also to other factors such as where and when it occurs; thus, figure 1 is not necessarily an accurate measure of the "size" of earthquakes in 1976. the point is that the physical process underlying an earthquake is highly complex; we therefore cannot express every detail of an earthquake by a simple straightforward parameter. Indeed, it would be very convenient if we could find a single number that represents the overall physical size of an earthquake. This was in fact the concept behind the Richter magnitude scale introduced in 1935. 

  10. Earthquakes: Predicting the unpredictable?

    USGS Publications Warehouse

    Hough, S.E.

    2005-01-01

    The earthquake prediction pendulum has swung from optimism in the 1970s to rather extreme pessimism in the 1990s. Earlier work revealed evidence of possible earthquake precursors: physical changes in the planet that signal that a large earthquake is on the way. Some respected earthquake scientists argued that earthquakes are likewise fundamentally unpredictable. The fate of the Parkfield prediction experiment appeared to support their arguments: A moderate earthquake had been predicted along a specified segment of the central San Andreas fault within five years of 1988, but had failed to materialize on schedule. At some point, however, the pendulum began to swing back. Reputable scientists began using the "P-word" in not only polite company, but also at meetings and even in print. If the optimism regarding earthquake prediction can be attributed to any single cause, it might be scientists' burgeoning understanding of the earthquake cycle.

  11. Earthquakes: hydrogeochemical precursors

    USGS Publications Warehouse

    Ingebritsen, Steven E.; Manga, Michael

    2014-01-01

    Earthquake prediction is a long-sought goal. Changes in groundwater chemistry before earthquakes in Iceland highlight a potential hydrogeochemical precursor, but such signals must be evaluated in the context of long-term, multiparametric data sets.

  12. Self-Organized Earthquakes

    NASA Astrophysics Data System (ADS)

    Rundle, J. B.; Holliday, J. R.; Turcotte, D. L.; Klein, W.

    2011-12-01

    Self-Organized Criticality was proposed by the Per Bak et al. [1] as a means of explaining scaling laws observed in driven natural systems, usually in (slowly) driven threshold systems. The example used by Bak was a simple cellular automaton model of a sandpile, in which grains of sand were slowly dropped (randomly) onto a flat plate. After a period of time, during which the 'critical state' was approached, a series of self-similar avalanches would begin. Scaling exponents for the frequency-area statistics of the sandpile avalanches were found to be approximately 1, a value that characterizes 'flicker noise' in natural systems. SOC is associated with a critical point in the phase diagram of the system, and it was found that the usual 2-scaling field theory applies. A model related to SOC is the Self-Organized Spinodal (SOS), or intermittent criticality model. Here a slow but persistent driving force leads to quasi-periodic approach to, and retreat from, the classical limit of stability, or spinodal. Scaling exponents for this model can be related to Gutenberg-Richter and Omori exponents observed in earthquake systems. In contrast to SOC models, nucleation, both classical and non-classical types, is possible in SOS systems. Tunneling or nucleation rates can be computed from Langer-Klein-Landau-Ginzburg theories for comparison to observations. Nucleating droplets play a role similar to characteristic earthquake events. Simulations of these systems reveals much of the phenomenology associated with earthquakes and other types of "burst" dynamics. Whereas SOC is characterized by the full scaling spectrum of avalanches, SOS is characterized by both system-size events above the nominal frequency-size scaling curve, and scaling of small events. Applications to other systems including integrate-and-fire neural networks and financial crashes will be discussed. [1] P. Bak, C. Tang and K. Weisenfeld, Self-Organized Criticality, Phys. Rev. Lett., 59, 381 (1987).

  13. Variability of megathrust earthquakes in the world revealed by the 2011 Tohoku-oki Earthquake

    NASA Astrophysics Data System (ADS)

    Koyama, Junji; Yoshizawa, Kazunori; Yomogida, Kiyoshi; Tsuzuki, Motohiro

    2012-12-01

    The seismicity of the Pacific coast of Tohoku, Japan, has been investigated in detail and characterized into regional seismic segments. The 2011 megathrust earthquake of M w 9.0 on 11 March ruptured almost all of the segments in that area, causing devastating tsunamis. The prime factor that had not been recognized before is the double segmentation along the Japan trench: The apparent absence of earthquakes in the trench-ward segments as opposed to the Japan Island-ward segments that have repeated smaller earthquakes. We term this pattern of seismic activity `along-dip double segmentation (ADDS)'. The 2011 Tohoku megathrust earthquake is typical of a class of great earthquakes different from that of the 1960 Chile earthquake, in which a young and buoyant plate is subducting rapidly under the continental plate. In the 1960 Chile case, the seismic activity is characterized by `along-strike single segmentation (ASSS)', where there is weak seismic activity before the main event all over the plate interface of the subduction zone. We study the greatest earthquakes around the world and find that there is a variety of megathrust earthquakes characterized by ASSS to ADDS, where the 2004 Sumatra-Andaman, the 1960 Chile, the 1964 Alaska and the 2011 Tohoku-oki earthquakes are typical end-members.

  14. Testing the USGS 3D San Francisco Bay Area Seismic Velocity Model using Observations of 0.5 to 2 s Surface Waves from Local and Regional Earthquakes (Invited)

    NASA Astrophysics Data System (ADS)

    Brocher, T. M.; Frankel, A. D.; Oppenheimer, D. H.; Fletcher, J. B.; Luetgert, J. H.

    2010-12-01

    We summarize recent observations of long-period (0.5 - 2 s) seismic waves from seven local and regional earthquakes in the magnitude range 3.5 - 6.5, made using accelerograph arrays in the Sacramento/San Joaquin Delta, in the San Leandro basin, and in the Livermore Valley. The observations were made on both isolated accelerometers (both NetQuakes and traditional instruments) and on arrays consisting of clusters of 3 instruments with an aperture of 200-300 meters. These recordings demonstrate that large-amplitude, long-period surface wave arrivals are commonly observed in the urbanized low-lying areas in the East Bay. In the Sacramento/San Joaquin Delta, late arriving Rayleigh waves observed on the vertical component have apparent velocities of about 610 m/s although they range from 300 to 1000 m/s for waves having a period of about 2 s. The azimuth of the arrivals is within 20 degrees of that expected for direct propagation from the epicenters indicating that they are related to the low seismic velocity of the shallow sediments in the Great Valley. Strong basin surface waves produced by the September 6, 2008 M4.1 Alamo earthquake observed throughout San Leandro and Oakland substantially increase the duration of shaking at periods of 1 sec and longer. These basin surface waves exhibit dispersion with group velocities as low as about 300 m/s and are apparent at frequencies from 0.8 - 2 s. These observations indicate that relatively shallow sedimentary basins, such as the San Leandro basin with a sediment thickness of about 1 km, support sizeable basin surface waves that amplify and prolong ground shaking. The M4.1 Alamo earthquake also produced a strong basin surface wave in the Livermore Valley, observed by our array in Pleasanton, that strongly amplifies periods of 0.5 s and longer. Array analysis indicates that late arrivals represent surface waves from an azimuth more westerly than that of the hypocenter. These surface waves are currently not well modeled by the

  15. Izmit, Turkey 1999 Earthquake Interferogram

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This image is an interferogram that was created using pairs of images taken by Synthetic Aperture Radar (SAR). The images, acquired at two different times, have been combined to measure surface deformation or changes that may have occurred during the time between data acquisition. The images were collected by the European Space Agency's Remote Sensing satellite (ERS-2) on 13 August 1999 and 17 September 1999 and were combined to produce these image maps of the apparent surface deformation, or changes, during and after the 17 August 1999 Izmit, Turkey earthquake. This magnitude 7.6 earthquake was the largest in 60 years in Turkey and caused extensive damage and loss of life. Each of the color contours of the interferogram represents 28 mm (1.1 inches) of motion towards the satellite, or about 70 mm (2.8 inches) of horizontal motion. White areas are outside the SAR image or water of seas and lakes. The North Anatolian Fault that broke during the Izmit earthquake moved more than 2.5 meters (8.1 feet) to produce the pattern measured by the interferogram. Thin red lines show the locations of fault breaks mapped on the surface. The SAR interferogram shows that the deformation and fault slip extended west of the surface faults, underneath the Gulf of Izmit. Thick black lines mark the fault rupture inferred from the SAR data. Scientists are using the SAR interferometry along with other data collected on the ground to estimate the pattern of slip that occurred during the Izmit earthquake. This then used to improve computer models that predict how this deformation transferred stress to other faults and to the continuation of the North Anatolian Fault, which extends to the west past the large city of Istanbul. These models show that the Izmit earthquake further increased the already high probability of a major earthquake near Istanbul.

  16. Fault failure with moderate earthquakes

    USGS Publications Warehouse

    Johnston, M.J.S.; Linde, A.T.; Gladwin, M.T.; Borcherdt, R.D.

    1987-01-01

    High resolution strain and tilt recordings were made in the near-field of, and prior to, the May 1983 Coalinga earthquake (ML = 6.7, ?? = 51 km), the August 4, 1985, Kettleman Hills earthquake (ML = 5.5, ?? = 34 km), the April 1984 Morgan Hill earthquake (ML = 6.1, ?? = 55 km), the November 1984 Round Valley earthquake (ML = 5.8, ?? = 54 km), the January 14, 1978, Izu, Japan earthquake (ML = 7.0, ?? = 28 km), and several other smaller magnitude earthquakes. These recordings were made with near-surface instruments (resolution 10-8), with borehole dilatometers (resolution 10-10) and a 3-component borehole strainmeter (resolution 10-9). While observed coseismic offsets are generally in good agreement with expectations from elastic dislocation theory, and while post-seismic deformation continued, in some cases, with a moment comparable to that of the main shock, preseismic strain or tilt perturbations from hours to seconds (or less) before the main shock are not apparent above the present resolution. Precursory slip for these events, if any occurred, must have had a moment less than a few percent of that of the main event. To the extent that these records reflect general fault behavior, the strong constraint on the size and amount of slip triggering major rupture makes prediction of the onset times and final magnitudes of the rupture zones a difficult task unless the instruments are fortuitously installed near the rupture initiation point. These data are best explained by an inhomogeneous failure model for which various areas of the fault plane have either different stress-slip constitutive laws or spatially varying constitutive parameters. Other work on seismic waveform analysis and synthetic waveforms indicates that the rupturing process is inhomogeneous and controlled by points of higher strength. These models indicate that rupture initiation occurs at smaller regions of higher strength which, when broken, allow runaway catastrophic failure. ?? 1987.

  17. Redefining Earthquakes and the Earthquake Machine

    ERIC Educational Resources Information Center

    Hubenthal, Michael; Braile, Larry; Taber, John

    2008-01-01

    The Earthquake Machine (EML), a mechanical model of stick-slip fault systems, can increase student engagement and facilitate opportunities to participate in the scientific process. This article introduces the EML model and an activity that challenges ninth-grade students' misconceptions about earthquakes. The activity emphasizes the role of models…

  18. Earthquakes, October 1975

    USGS Publications Warehouse

    Person, W.J.

    1976-01-01

    October was an active month seismically, although there were no damaging earthquakes in the United States. Several States experienced earthquakes that were felt sharply. There were four major earthquakes in other parts of the world, including a magntidue 7.4 in the Philippine Islands that killed on person. 

  19. Children's Ideas about Earthquakes

    ERIC Educational Resources Information Center

    Simsek, Canan Lacin

    2007-01-01

    Earthquake, a natural disaster, is among the fundamental problems of many countries. If people know how to protect themselves from earthquake and arrange their life styles in compliance with this, damage they will suffer will reduce to that extent. In particular, a good training regarding earthquake to be received in primary schools is considered…

  20. Real Earthquakes, Real Learning

    ERIC Educational Resources Information Center

    Schomburg, Aaron

    2003-01-01

    One teacher took her class on a year long earthquake expedition. The goal was to monitor the occurrences of real earthquakes during the year and mark their locations with push pins on a wall-sized world map in the hallway outside the science room. The purpose of the project was to create a detailed picture of the earthquakes that occurred…

  1. Earthquake and Schools. [Videotape].

    ERIC Educational Resources Information Center

    Federal Emergency Management Agency, Washington, DC.

    Designing schools to make them more earthquake resistant and protect children from the catastrophic collapse of the school building is discussed in this videotape. It reveals that 44 of the 50 U.S. states are vulnerable to earthquake, but most schools are structurally unprepared to take on the stresses that earthquakes exert. The cost to the…

  2. School Safety and Earthquakes.

    ERIC Educational Resources Information Center

    Dwelley, Laura; Tucker, Brian; Fernandez, Jeanette

    1997-01-01

    A recent assessment of earthquake risk to Quito, Ecuador, concluded that many of its public schools are vulnerable to collapse during major earthquakes. A subsequent examination of 60 buildings identified 15 high-risk buildings. These schools were retrofitted to meet standards that would prevent injury even during Quito's largest earthquakes. US…

  3. The 1945 Balochistan earthquake and probabilistic tsunami hazard assessment for the Makran subduction zone

    NASA Astrophysics Data System (ADS)

    Höchner, Andreas; Babeyko, Andrey; Zamora, Natalia

    2014-05-01

    Iran and Pakistan are countries quite frequently affected by destructive earthquakes. For instance, the magnitude 6.6 Bam earthquake in 2003 in Iran with about 30'000 casualties, or the magnitude 7.6 Kashmir earthquake 2005 in Pakistan with about 80'000 casualties. Both events took place inland, but in terms of magnitude, even significantly larger events can be expected to happen offshore, at the Makran subduction zone. This small subduction zone is seismically rather quiescent, but a tsunami caused by a thrust event in 1945 (Balochistan earthquake) led to about 4000 casualties. Nowadays, the coastal regions are more densely populated and vulnerable to similar events. Additionally, some recent publications raise the question of the possiblity of rare but huge magnitude 9 events at the Makran subduction zone. We first model the historic Balochistan event and its effect in terms of coastal wave heights, and then generate various synthetic earthquake and tsunami catalogs including the possibility of large events in order to asses the tsunami hazard at the affected coastal regions. Finally, we show how an effective tsunami early warning could be achieved by the use of an array of high-precision real-time GNSS (Global Navigation Satellite System) receivers along the coast.

  4. Earthquakes and trauma: review of triage and injury-specific, immediate care.

    PubMed

    Gautschi, Oliver P; Cadosch, Dieter; Rajan, Gunesh; Zellweger, René

    2008-01-01

    Earthquakes present a major threat to mankind. Increasing knowledge about geophysical interactions, progressing architectural technology, and improved disaster management algorithms have rendered modern populations less susceptible to earthquakes. Nevertheless, the mass casualties resulting from earthquakes in Great Kanto (Japan), Ancash (Peru), Tangshan (China), Guatemala, Armenia, and Izmit (Turkey) or the recent earthquakes in Bhuj (India), Bam (Iran), Sumatra (Indonesia) and Kashmir (Pakistan) indicate the devastating effect earthquakes can have on both individual and population health. Appropriate preparation and implementation of crisis management algorithms are of utmost importance to ensure a large-scale medical-aid response is readily available following a devastating event. In particular, efficient triage is vital to optimize the use of limited medical resources and to effectively mobilize these resources so as to maximize patient salvage. However, the main priorities of disaster rescue teams are the rescue and provision of emergency care for physical trauma. Furthermore, the establishment of transport evacuation corridors, a feature often neglected, is essential in order to provide the casualties with a chance for survival. The optimal management of victims under such settings is discussed, addressing injuries of the body and psyche by means of simple diagnostic and therapeutic procedures globally applicable and available.

  5. Operational earthquake forecasting can enhance earthquake preparedness

    USGS Publications Warehouse

    Jordan, T.H.; Marzocchi, W.; Michael, A.J.; Gerstenberger, M.C.

    2014-01-01

    We cannot yet predict large earthquakes in the short term with much reliability and skill, but the strong clustering exhibited in seismic sequences tells us that earthquake probabilities are not constant in time; they generally rise and fall over periods of days to years in correlation with nearby seismic activity. Operational earthquake forecasting (OEF) is the dissemination of authoritative information about these time‐dependent probabilities to help communities prepare for potentially destructive earthquakes. The goal of OEF is to inform the decisions that people and organizations must continually make to mitigate seismic risk and prepare for potentially destructive earthquakes on time scales from days to decades. To fulfill this role, OEF must provide a complete description of the seismic hazard—ground‐motion exceedance probabilities as well as short‐term rupture probabilities—in concert with the long‐term forecasts of probabilistic seismic‐hazard analysis (PSHA).

  6. Electric pulses some minutes before earthquake occurrences

    SciTech Connect

    Varotsos, P. A.; Sarlis, N. V.; Skordas, E. S.; Lazaridou, M. S.

    2007-02-05

    Electric and magnetic pulses are measured shortly (some minutes) before earthquakes. These pulses differ greatly from the seismic electric signals, which have appreciably longer lead times (days to months). In the case of 1995 Grevena-Kozani earthquake with a magnitude of 6.8, the time difference of {approx_equal}1 s was observed between the recordings of the electric and magnetic components at Ioannina station, providing further support that the pulses were not from local man-made source but most probably from the epicentral area about 100 km away. A tentative explanation of the phenomenon is proposed considering what happens in the very last stage before the earthquake occurrence.

  7. Threat of an earthquake right under the capital in Japan

    USGS Publications Warehouse

    Rikitake, T.

    1990-01-01

    Tokyo, Japan's capital, has been enjoying a seismically quiet period following the 1923 Kanto earthquake of magnitude 7.9 that killed more than 140,000 people. Such a quiet period seems likely to be a repetition of the 80-year quiescence after the great 1703 Genroku earthquake of magntidue 8.2 that occurred in an epicentral area adjacent to that of the 1923 Kanto earthquake. In 1784, seismic activity immediately under the capital area revived with occasional occurrence of magnitude 6 to 7 shocks. Earthquakes of this class tended to occur more frequently as time went on and they eventually culminated in the 1923 Kanto earthquake. As more than 60 years have passed since the Kanto earthquake, we may well expect another revival of activity immediately under the capital area

  8. Surface faulting and paleoseismic history of the 1932 Cedar Mountain earthquake area, west-central Nevada, and implications for modern tectonics of the Walker Lane

    USGS Publications Warehouse

    Bell, J.W.; DePolo, C.M.; Ramelli, A.R.; Sarna-Wojcicki, A. M.; Meyer, C.E.

    1999-01-01

    The 1932 Cedar Mountain earthquake (Ms 7.2) was one of the largest historical events in the Walker Lane region of western Nevada, and it produced a complicated strike-slip rupture pattern on multiple Quaternary faults distributed through three valleys. Primary, right-lateral surface ruptures occurred on north-striking faults in Monte Cristo Valley; small-scale lateral and normal offsets occurred in Stewart Valley; and secondary, normal faulting occurred on north-northeast-striking faults in the Gabbs Valley epicentral region. A reexamination of the surface ruptures provides new displacement and fault-zone data: maximum cumulative offset is estimated to be 2.7 m, and newly recognized faults extend the maximum width and end-to-end length of the rupture zone to 17 and 75 km, respectively. A detailed Quaternary allostratigraphic chronology based on regional alluvialgeomorphic relationships, tephrochronology, and radiocarbon dating provides a framework for interpreting the paleoseismic history of the fault zone. A late Wisconsinan alluvial-fan and piedmont unit containing a 32-36 ka tephra layer is a key stratigraphic datum for paleoseismic measurements. Exploratory trenching and radiocarbon dating of tectonic stratigraphy provide the first estimates for timing of late Quaternary faulting along the Cedar Mountain fault zone. Three trenches display evidence for six faulting events, including that in 1932, during the past 32-36 ka. Radiocarbon dating of organic soils interstratified with tectonically ponded silts establishes best-fit ages of the pre-1932 events at 4, 5,12,15, and 18 ka, each with ??2 ka uncertainties. On the basis of an estimated cumulative net slip of 6-12 m for the six faulting events, minimum and maximum late Quaternary slip rates are 0.2 and 0.7 mm/yr, respectively, and the preferred rate is 0.4-0.5 mm/yr. The average recurrence (interseismic) interval is 3600 yr. The relatively uniform thickness of the ponded deposits suggests that similar

  9. Characterizing long-term radon concentration changes in a geothermal area for correlation with volcanic earthquakes and reservoir temperatures: A case study from Mt. Aso, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Koike, Katsuaki; Yoshinaga, Tohru; Asaue, Hisafumi

    2014-04-01

    The purpose of this study is to characterize in detail the temporal changes in Rn (radon-222) concentration in soil gases near fumaroles and clarify its correlation with volcanic earthquakes and temperatures in two geothermal reservoirs. Mt. Aso crater in southwest Japan, which has two reservoirs on its western side estimated by magnetotelluric survey to be at about 2 km in depth, was selected for this study. For the long-term survey, the α scintillation counter method was used weekly for 12.5 years at the three hot springs within a 2-km range. Rn concentrations were calculated using the CRAS method, a calculation method that considers radioactive equilibrium or nonequilibrium state of the soil gas. Rn concentrations generally showed similar fluctuation patterns among the sites. CRAS was used as a new indicator for evaluating the age of the soil gas. This age corresponds to the elapsed time determined from the generation of Rn based on the measurement of the numbers of atoms of Rn and its daughter 218Po at the start of measurement. In comparing the Rn data with the history of earthquakes in the Aso caldera, volcanic seismicity was identified as a major controlling factor in the sudden increase and decrease in Rn concentration as a function of age. For more precise detections of change, Rn concentrations were measured continuously at one site by pumping soil gas from a borehole and using an ionization chamber over 2.5 years. Five chemical components (He, H2, N2, CH4, and CO2) were then measured by gas chromatography at 1-week intervals. Because Rn concentrations are affected strongly by atmospheric temperatures, the residual components were obtained by subtracting the trend of the components from the original data. Chemical component data were used to estimate the temperature and pressure in the reservoir at the site; temperatures ranged from 229 to 280 °C, (average 265 °C, average pressure 80 MPa). Residual Rn concentrations showed a clear correlation with

  10. BAM 1 and RECEPTOR-LIKE PROTEIN KINASE 2 constitute a signaling pathway and modulate CLE peptide-triggered growth inhibition in Arabidopsis root.

    PubMed

    Shimizu, Noriko; Ishida, Takashi; Yamada, Masashi; Shigenobu, Shuji; Tabata, Ryo; Kinoshita, Atsuko; Yamaguchi, Katsushi; Hasebe, Mitsuyasu; Mitsumasu, Kanako; Sawa, Shinichiro

    2015-12-01

    Ligand receptor-based signaling is a means of cell-to-cell communication for coordinating developmental and physiological processes in multicellular organisms. In plants, cell-producing meristems utilize this signaling to regulate their activities and ensure for proper development. Shoot and root systems share common requirements for carrying out this process; however, its molecular basis is largely unclear. It has been suggested that synthetic CLV3/EMBRYO SURROUNDING REGION (CLE) peptide shrinks the root meristem through the actions of CLAVATA2 (CLV2) and the RECEPTOR-LIKE PROTEIN KINASE 2 (RPK2) pathway in Arabidopsis thaliana. Our genetic screening for mutations that resist CLE peptide signaling in roots determined that BAM1, which is a member of the leucine-rich repeat receptor-like kinase (LRR-RLK) family, is also involved in this pathway. BAM1 is preferentially expressed in the root tip, including the quiescent center and its surrounding stem cells. Our genetic analysis revealed that BAM1 functions together with RPK2. Using coimmunoprecipitation assay, we showed that BAM1 is capable of forming heteromeric complexes with RPK2. These findings suggest that the BAM1 and RPK2 receptors constitute a signaling pathway that modulates cell proliferation in the root meristem and that related molecules are employed in root and shoot meristems. PMID:26083273

  11. Spatial Seismicity Rates and Maximum Magnitudes for Background Earthquakes

    USGS Publications Warehouse

    Petersen, Mark D.; Mueller, Charles S.; Frankel, Arthur D.; Zeng, Yuehua

    2008-01-01

    The background seismicity model is included to account for M 5.0 - 6.5 earthquakes on faults and for random M 5.0 ? 7.0 earthquakes that do not occur on faults included in the model (as in earlier models of Frankel et al., 1996, 2002 and Petersen et al., 1996). We include four different classes of earthquake sources in the California background seismicity model: (1) gridded (smoothed) seismicity, (2) regional background zones, (3) special fault zone models, and (4) shear zones (also referred to as C zones). The gridded (smoothed) seismicity model, the regional background zone model, and the special fault zones use a declustered earthquake catalog for calculation of earthquake rates. Earthquake rates in shear zones are estimated from the geodetically determined rate of deformation across an area of high strain rate. We use a truncated exponential (Gutenberg-Richter, 1944) magnitude-frequency distribution to account for earthquakes in the background models.

  12. Incubation of Chile's 1960 Earthquake

    NASA Astrophysics Data System (ADS)

    Atwater, B. F.; Cisternas, M.; Salgado, I.; Machuca, G.; Lagos, M.; Eipert, A.; Shishikura, M.

    2003-12-01

    Infrequent occurrence of giant events may help explain how the 1960 Chile earthquake attained M 9.5. Although old documents imply that this earthquake followed great earthquakes of 1575, 1737 and 1837, only three earthquakes of the past 1000 years produced geologic records like those for 1960. These earlier earthquakes include the 1575 event but not 1737 or 1837. Because the 1960 earthquake had nearly twice the seismic slip expected from plate convergence since 1837, much of the strain released in 1960 may have been accumulating since 1575. Geologic evidence for such incubation comes from new paleoseismic findings at the R¡o Maullin estuary, which indents the Pacific coast at 41.5§ S midway along the 1960 rupture. The 1960 earthquake lowered the area by 1.5 m, and the ensuing tsunami spread sand across lowland soils. The subsidence killed forests and changed pastures into sandy tidal flats. Guided by these 1960 analogs, we inferred tsunami and earthquake history from sand sheets, tree rings, and old maps. At Chuyaquen, 10 km upriver from the sea, we studied sand sheets in 31 backhoe pits on a geologic transect 1 km long. Each sheet overlies the buried soil of a former marsh or meadow. The sand sheet from 1960 extends the entire length of the transect. Three earlier sheets can be correlated at least half that far. The oldest one, probably a tsunami deposit, surrounds herbaceous plants that date to AD 990-1160. Next comes a sandy tidal-flat deposit dated by stratigraphic position to about 1000-1500. The penultimate sheet is a tsunami deposit younger than twigs from 1410-1630. It probably represents the 1575 earthquake, whose accounts of shaking, tsunami, and landslides rival those of 1960. In that case, the record excludes the 1737 and 1837 events. The 1737 and 1837 events also appear missing in tree-ring evidence from islands of Misquihue, 30 km upriver from the sea. Here the subsidence in 1960 admitted brackish tidal water that defoliated tens of thousands of

  13. Crowdsourced earthquake early warning.

    PubMed

    Minson, Sarah E; Brooks, Benjamin A; Glennie, Craig L; Murray, Jessica R; Langbein, John O; Owen, Susan E; Heaton, Thomas H; Iannucci, Robert A; Hauser, Darren L

    2015-04-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing. PMID:26601167

  14. Crowdsourced earthquake early warning

    PubMed Central

    Minson, Sarah E.; Brooks, Benjamin A.; Glennie, Craig L.; Murray, Jessica R.; Langbein, John O.; Owen, Susan E.; Heaton, Thomas H.; Iannucci, Robert A.; Hauser, Darren L.

    2015-01-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an Mw (moment magnitude) 7 earthquake on California’s Hayward fault, and real data from the Mw 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing. PMID:26601167

  15. Crowdsourced earthquake early warning.

    PubMed

    Minson, Sarah E; Brooks, Benjamin A; Glennie, Craig L; Murray, Jessica R; Langbein, John O; Owen, Susan E; Heaton, Thomas H; Iannucci, Robert A; Hauser, Darren L

    2015-04-01

    Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous. Through controlled tests of consumer devices, simulation of an M w (moment magnitude) 7 earthquake on California's Hayward fault, and real data from the M w 9 Tohoku-oki earthquake, we demonstrate that EEW could be achieved via crowdsourcing.

  16. POST Earthquake Debris Management - AN Overview

    NASA Astrophysics Data System (ADS)

    Sarkar, Raju

    Every year natural disasters, such as fires, floods, earthquakes, hurricanes, landslides, tsunami, and tornadoes, challenge various communities of the world. Earthquakes strike with varying degrees of severity and pose both short- and long-term challenges to public service providers. Earthquakes generate shock waves and displace the ground along fault lines. These seismic forces can bring down buildings and bridges in a localized area and damage buildings and other structures in a far wider area. Secondary damage from fires, explosions, and localized flooding from broken water pipes can increase the amount of debris. Earthquake debris includes building materials, personal property, and sediment from landslides. The management of this debris, as well as the waste generated during the reconstruction works, can place significant challenges on the national and local capacities. Debris removal is a major component of every post earthquake recovery operation. Much of the debris generated from earthquake is not hazardous. Soil, building material, and green waste, such as trees and shrubs, make up most of the volume of earthquake debris. These wastes not only create significant health problems and a very unpleasant living environment if not disposed of safely and appropriately, but also can subsequently impose economical burdens on the reconstruction phase. In practice, most of the debris may be either disposed of at landfill sites, reused as materials for construction or recycled into useful commodities Therefore, the debris clearance operation should focus on the geotechnical engineering approach as an important post earthquake issue to control the quality of the incoming flow of potential soil materials. In this paper, the importance of an emergency management perspective in this geotechnical approach that takes into account the different criteria related to the operation execution is proposed by highlighting the key issues concerning the handling of the construction

  17. Earthquake forecasting and warning

    SciTech Connect

    Rikitake, T.

    1983-01-01

    This review briefly describes two other books on the same subject either written or partially written by Rikitake. In this book, the status of earthquake prediction efforts in Japan, China, the Soviet Union, and the United States are updated. An overview of some of the organizational, legal, and societal aspects of earthquake prediction in these countries is presented, and scientific findings of precursory phenomena are included. A summary of circumstances surrounding the 1975 Haicheng earthquake, the 1978 Tangshan earthquake, and the 1976 Songpan-Pingwu earthquake (all magnitudes = 7.0) in China and the 1978 Izu-Oshima earthquake in Japan is presented. This book fails to comprehensively summarize recent advances in earthquake prediction research.

  18. Frog Swarms: Earthquake Precursors or False Alarms?

    PubMed Central

    Grant, Rachel A.; Conlan, Hilary

    2013-01-01

    Simple Summary Media reports linking unusual animal behaviour with earthquakes can potentially create false alarms and unnecessary anxiety among people that live in earthquake risk zones. Recently large frog swarms in China and elsewhere have been reported as earthquake precursors in the media. By examining international media reports of frog swarms since 1850 in comparison to earthquake data, it was concluded that frog swarms are naturally occurring dispersal behaviour of juveniles and are not associated with earthquakes. However, the media in seismic risk areas may be more likely to report frog swarms, and more likely to disseminate reports on frog swarms after earthquakes have occurred, leading to an apparent link between frog swarms and earthquakes. Abstract In short-term earthquake risk forecasting, the avoidance of false alarms is of utmost importance to preclude the possibility of unnecessary panic among populations in seismic hazard areas. Unusual animal behaviour prior to earthquakes has been reported for millennia but has rarely been scientifically documented. Recently large migrations or unusual behaviour of amphibians have been linked to large earthquakes, and media reports of large frog and toad migrations in areas of high seismic risk such as Greece and China have led to fears of a subsequent large earthquake. However, at certain times of year large migrations are part of the normal behavioural repertoire of amphibians. News reports of “frog swarms” from 1850 to the present day were examined for evidence that this behaviour is a precursor to large earthquakes. It was found that only two of 28 reported frog swarms preceded large earthquakes (Sichuan province, China in 2008 and 2010). All of the reported mass migrations of amphibians occurred in late spring, summer and autumn and appeared to relate to small juvenile anurans (frogs and toads). It was concluded that most reported “frog swarms” are actually normal behaviour, probably caused by

  19. Prediction of earthquake-triggered landslide event sizes

    NASA Astrophysics Data System (ADS)

    Braun, Anika; Havenith, Hans-Balder; Schlögel, Romy

    2016-04-01

    Seismically induced landslides are a major environmental effect of earthquakes, which may significantly contribute to related losses. Moreover, in paleoseismology landslide event sizes are an important proxy for the estimation of the intensity and magnitude of past earthquakes and thus allowing us to improve seismic hazard assessment over longer terms. Not only earthquake intensity, but also factors such as the fault characteristics, topography, climatic conditions and the geological environment have a major impact on the intensity and spatial distribution of earthquake induced landslides. We present here a review of factors contributing to earthquake triggered slope failures based on an "event-by-event" classification approach. The objective of this analysis is to enable the short-term prediction of earthquake triggered landslide event sizes in terms of numbers and size of the affected area right after an earthquake event occurred. Five main factors, 'Intensity', 'Fault', 'Topographic energy', 'Climatic conditions' and 'Surface geology' were used to establish a relationship to the number and spatial extend of landslides triggered by an earthquake. The relative weight of these factors was extracted from published data for numerous past earthquakes; topographic inputs were checked in Google Earth and through geographic information systems. Based on well-documented recent earthquakes (e.g. Haiti 2010, Wenchuan 2008) and on older events for which reliable extensive information was available (e.g. Northridge 1994, Loma Prieta 1989, Guatemala 1976, Peru 1970) the combination and relative weight of the factors was calibrated. The calibrated factor combination was then applied to more than 20 earthquake events for which landslide distribution characteristics could be cross-checked. One of our main findings is that the 'Fault' factor, which is based on characteristics of the fault, the surface rupture and its location with respect to mountain areas, has the most important

  20. Lessons in bridge damage learned from the Wenchuan earthquake

    NASA Astrophysics Data System (ADS)

    Yen, W. Phillip; Chen, Genda; Yashinski, Mark; Hashash, Youssef; Holub, Curtis; Wang, Kehai; Guo, Xiaodong

    2009-06-01

    A strong earthquake occurred in Wenchuan County, Sichuan Province, China, on May 12, 2008. Shortly after the earthquake, the Turner-Fairbank Highway Research Center of the Federal Highway Administration, in partnership with the Research Institute of Highways, the Ministry of Communication of China, led a reconnaissance team to conduct a post-earthquake bridge performance investigation of the transportation system in the earthquake affected areas. The U.S. transportation system reconnaissance team visited the area during July 20-24, 2008. This paper presents the findings and lessons learned by the team.

  1. Prediction model of earthquake with the identification of earthquake source polarity mechanism through the focal classification using ANFIS and PCA technique

    NASA Astrophysics Data System (ADS)

    Setyonegoro, W.

    2016-05-01

    Incidence of earthquake disaster has caused casualties and material in considerable amounts. This research has purposes to predictability the return period of earthquake with the identification of the mechanism of earthquake which in case study area in Sumatra. To predict earthquakes which training data of the historical earthquake is using ANFIS technique. In this technique the historical data set compiled into intervals of earthquake occurrence daily average in a year. Output to be obtained is a model return period earthquake events daily average in a year. Return period earthquake occurrence models 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, model predicted a return period earthquake events for the average monthly return period showed a correlation coefficient 0.014562.

  2. A revised “earthquake report” questionaire

    USGS Publications Warehouse

    Stover, C.; Reagor, G.; Simon, R.

    1976-01-01

    The U.S geological Survey is responsible for conducting intensity and damage surveys following felt or destructive earthquakes in the United States. Shortly after a felt or damaging earthquake occurs, a canvass of the affected area is made. Specially developed questionnaires are mailed to volunteer observers located within the estimated felt area. These questionnaires, "Earthquake Reports," are filled out by the observers and returned to the Survey's National Earthquake Information Service, which is located in Colorado. They are then evaluated, and, based on answers to questions about physical effects seen or felt, each canvassed location is assigned to the various locations, they are plotted on an intensity distribution map. When all of the intensity data have been plotted, isoseismals can then be contoured through places where equal intensity was experienced. The completed isoseismal map yields a detailed picture of the earthquake, its effects, and its felt area. All of the data and maps are published quarterly in a U.S Geological Survey Circular series entitled "Earthquakes in the United States".  

  3. Smartphone MEMS accelerometers and earthquake early warning

    NASA Astrophysics Data System (ADS)

    Kong, Q.; Allen, R. M.; Schreier, L.; Kwon, Y. W.

    2015-12-01

    The low cost MEMS accelerometers in the smartphones are attracting more and more attentions from the science community due to the vast number and potential applications in various areas. We are using the accelerometers inside the smartphones to detect the earthquakes. We did shake table tests to show these accelerometers are also suitable to record large shakings caused by earthquakes. We developed an android app - MyShake, which can even distinguish earthquake movements from daily human activities from the recordings recorded by the accelerometers in personal smartphones and upload trigger information/waveform to our server for further analysis. The data from these smartphones forms a unique datasets for seismological applications, such as earthquake early warning. In this talk I will layout the method we used to recognize earthquake-like movement from single smartphone, and the overview of the whole system that harness the information from a network of smartphones for rapid earthquake detection. This type of system can be easily deployed and scaled up around the global and provides additional insights of the earthquake hazards.

  4. New geological perspectives on earthquake recurrence models

    SciTech Connect

    Schwartz, D.P.

    1997-02-01

    In most areas of the world the record of historical seismicity is too short or uncertain to accurately characterize the future distribution of earthquakes 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 earthquakes depends on how well one can quantify the past behavior of earthquake 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 earthquake sources. These studies quantify (a) the timing of individual past earthquakes and fault slip rates, which lead to estimates of recurrence intervals and the development of recurrence models and (b) the amount of displacement during individual events, which allows estimates of the sizes of past earthquakes on a fault. When timing and slip per event are combined with information on fault zone geometry and structure, models 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 earthquake engine--the cycle of stress build-up and release.

  5. Non-Double-Couple Earthquakes 2. Observations

    USGS Publications Warehouse

    Miller, A.D.; Foulger, G.R.; Julian, B.R.

    1998-01-01

    Most studies assume that earthquakes have double-couple (DC) source mechanisms, corresponding to shear motion on planar faults. However, many well-recorded earthquakes have radiation patterns that depart radically from this model, indicating fundamentally different source processes. Seismic waves excited by advective processes, such as landslides and volcanic eruptions, are consistent with net forces rather than DCs. Some volcanic earthquakes also have single-force mechanisms, probably because of advection of magmatic fluids. Other volcanic earthquakes have mechanisms close to compensated linear vector dipoles and may be caused by magmatic intrusions. Shallow earthquakes in volcanic or geothermal areas and mines often have mechanisms with isotropic components, indicating volume changes of either explosive or implosive polarity. Such mechanisms are consistent with failure involving both shear and tensile faulting, which may be facilitated by high-pressure, high-temperature fluids. In mines, tunnels are cavities that may close. Deep-focus earthquakes occur within zones of polymorphic phase transformations in the upper mantle at depths where stick-slip instability cannot occur. Their mechanisms tend to be deviatoric (volume conserving), but non-DC, and their source processes are poorly understood. Automatic global moment tensor services routinely report statistically significant non-DC components for large earthquakes, but detailed reexamination of individual events is required to confirm such results.

  6. The Kashmir Earthquake Experience.

    PubMed

    Dhar, Shabir A; Halwai, Manzoor A; Mir, Mohammed R; Wani, Zaid A; Butt, M F; Bhat, Masood I; Hamid, Arshiya

    2007-02-01

    On October 8, 2005, a major earthquake measuring 7.6 on the Richter scale struck the Himalayan region of Kashmir. Around 90,000 people died in the mass disaster. The Bone and Joint Hospital in Kashmir found itself in a relatively unique situation of having to deal with the orthopedic morbidity generated by this quake. The hospital received 468 patients over a period of 10 days, out of which 463 were received over the initial 5 days. The admission for a single day peaked at 153 patients on the third day. Due to the unprecedented admission in terms of numbers the hospital utilized outreach methods to streamline admission by sending out specialists to the affected areas. Manpower was judiciously utilized to concentrate specialist advise where required. Besides documenting the pattern of trauma, this paper throws light on some unforeseen problems faced in dealing with a large number of patients far exceeding the normal capacity of the hospital.

  7. 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.

  8. Reconsidering earthquake scaling

    NASA Astrophysics Data System (ADS)

    Gomberg, J.; Wech, A.; Creager, K.; Obara, K.; Agnew, D.

    2016-06-01

    The relationship (scaling) between scalar moment, M0, and duration, T, potentially provides key constraints on the physics governing fault slip. The prevailing interpretation of M0-T observations proposes different scaling for fast (earthquakes) and slow (mostly aseismic) slip populations and thus fundamentally different driving mechanisms. We show that a single model of slip events within bounded slip zones may explain nearly all fast and slow slip M0-T observations, and both slip populations have a change in scaling, where the slip area growth changes from 2-D when too small to sense the boundaries to 1-D when large enough to be bounded. We present new fast and slow slip M0-T observations that sample the change in scaling in each population, which are consistent with our interpretation. We suggest that a continuous but bimodal distribution of slip modes exists and M0-T observations alone may not imply a fundamental difference between fast and slow slip.

  9. Preliminary results on earthquake triggered landslides for the Haiti earthquake (January 2010)

    NASA Astrophysics Data System (ADS)

    van Westen, Cees; Gorum, Tolga

    2010-05-01

    This study presents the first results on an analysis of the landslides triggered by the Ms 7.0 Haiti earthquake that occurred on January 12, 2010 in the boundary region of the Pacific Plate and the North American plate. The fault is a left lateral strike slip fault with a clear surface expression. According to the USGS earthquake information the Enriquillo-Plantain Garden fault system has not produced any major earthquake in the last 100 years, and historical earthquakes are known from 1860, 1770, 1761, 1751, 1684, 1673, and 1618, though none of these has been confirmed in the field as associated with this fault. We used high resolution satellite imagery available for the pre and post earthquake situations, which were made freely available for the response and rescue operations. We made an interpretation of all co-seismic landslides in the epicentral area. We conclude that the earthquake mainly triggered landslide in the northern slope of the fault-related valley and in a number of isolated area. The earthquake apparently didn't trigger many visible landslides within the slum areas on the slopes in the southern part of Port-au-Prince and Carrefour. We also used ASTER DEM information to relate the landslide occurrences with DEM derivatives.

  10. Testing hypotheses of earthquake occurrence

    NASA Astrophysics Data System (ADS)

    Kagan, Y. Y.; Jackson, D. D.; Schorlemmer, D.; Gerstenberger, M.

    2003-12-01

    We present a relatively straightforward likelihood method for testing those earthquake hypotheses that can be stated as vectors of earthquake rate density in defined bins of area, magnitude, and time. We illustrate the method as it will be applied to the Regional Earthquake Likelihood Models (RELM) project of the Southern California Earthquake Center (SCEC). Several earthquake forecast models are being developed as part of this project, and additional contributed forecasts are welcome. Various models are based on fault geometry and slip rates, seismicity, geodetic strain, and stress interactions. We would test models in pairs, requiring that both forecasts in a pair be defined over the same set of bins. Thus we offer a standard "menu" of bins and ground rules to encourage standardization. One menu category includes five-year forecasts of magnitude 5.0 and larger. Forecasts would be in the form of a vector of yearly earthquake rates on a 0.05 degree grid at the beginning of the test. Focal mechanism forecasts, when available, would be also be archived and used in the tests. The five-year forecast category may be appropriate for testing hypotheses of stress shadows from large earthquakes. Interim progress will be evaluated yearly, but final conclusions would be made on the basis of cumulative five-year performance. The second category includes forecasts of earthquakes above magnitude 4.0 on a 0.05 degree grid, evaluated and renewed daily. Final evaluation would be based on cumulative performance over five years. Other types of forecasts with different magnitude, space, and time sampling are welcome and will be tested against other models with shared characteristics. All earthquakes would be counted, and no attempt made to separate foreshocks, main shocks, and aftershocks. Earthquakes would be considered as point sources located at the hypocenter. For each pair of forecasts, we plan to compute alpha, the probability that the first would be wrongly rejected in favor of

  11. Sichuan Earthquake in China

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The Sichuan earthquake in China occurred on May 12, 2008, along faults within the mountains, but near and almost parallel the mountain front, northwest of the city of Chengdu. This major quake caused immediate and severe damage to many villages and cities in the area. Aftershocks pose a continuing danger, but another continuing hazard is the widespread occurrence of landslides that have formed new natural dams and consequently new lakes. These lakes are submerging roads and flooding previously developed lands. But an even greater concern is the possible rapid release of water as the lakes eventually overflow the new dams. The dams are generally composed of disintegrated rock debris that may easily erode, leading to greater release of water, which may then cause faster erosion and an even greater release of water. This possible 'positive feedback' between increasing erosion and increasing water release could result in catastrophic debris flows and/or flooding. The danger is well known to the Chinese earthquake response teams, which have been building spillways over some of the new natural dams.

    This ASTER image, acquired on June 1, 2008, shows two of the new large landslide dams and lakes upstream from the town of Chi-Kua-Kan at 32o12'N latitude and 104o50'E longitude. Vegetation is green, water is blue, and soil is grayish brown in this enhanced color view. New landslides appear bright off-white. The northern (top) lake is upstream from the southern lake. Close inspection shows a series of much smaller lakes in an elongated 'S' pattern along the original stream path. Note especially the large landslides that created the dams. Some other landslides in this area, such as the large one in the northeast corner of the image, occur only on the mountain slopes, so do not block streams, and do not form lakes.

  12. Innovative methodology for the synthesis of Ba-M hexaferrite BaFe{sub 12}O{sub 19} nanoparticles

    SciTech Connect

    Ahmed, M.A.; Helmy, N.; El-Dek, S.I.

    2013-09-01

    Graphical abstract: Transmission electron microscope images for the BaFe12O19. - Highlights: • BaFe{sub 12}O{sub 19}nanoparticles were prepared in single-phase from organometallic precursors. • BaFe{sub 12}O{sub 19} possesses small size 65 nm, H{sub C} = 3695 Oe and M{sub s} = 58 emu/g. • This method of preparation could be extended in the synthesis of other metal oxide nanoparticles. - Abstract: In this piece of work, high quality and homogeneity, barium hexaferrite (BaM) BaFe{sub 12}O{sub 19} nanoparticles were prepared from organometallic precursors for the 1st time. This method is based on the formation of supramolecular crystal structure of Ba[Fe(H{sub 3}NCH{sub 2}CH{sub 2}NH{sub 3})]Cl{sub 7}·8H{sub 2}O. The crystal structure, morphology and magnetic properties of BaFe{sub 12}O{sub 19} at two different annealing temperatures namely 1000 °C and 1200 °C were investigated using X-ray diffraction, transmission electron microscope TEM and vibrating sample magnetometry (VSM). The results show that monophasic nanoparticles of hexaferrites were obtained. Nanoparticles of crystallite size 40–50 nm distinguished by narrow distribution and excellent homogeneity were obtained with superior magnetic properties which suggested single-domain particles of Ba-M hexaferrite.

  13. The 2008 Wenchuan Earthquake and the Rise and Fall of Earthquake Prediction in China

    NASA Astrophysics Data System (ADS)

    Chen, Q.; Wang, K.

    2009-12-01

    Regardless of the future potential of earthquake prediction, it is presently impractical to rely on it to mitigate earthquake disasters. The practical approach is to strengthen the resilience of our built environment to earthquakes based on hazard assessment. But this was not common understanding in China when the M 7.9 Wenchuan earthquake struck the Sichuan Province on 12 May 2008, claiming over 80,000 lives. In China, earthquake prediction is a government-sanctioned and law-regulated measure of disaster prevention. A sudden boom of the earthquake prediction program in 1966-1976 coincided with a succession of nine M > 7 damaging earthquakes in the densely populated region of the country and the political chaos of the Cultural Revolution. It climaxed with the prediction of the 1975 Haicheng earthquake, which was due mainly to an unusually pronounced foreshock sequence and the extraordinary readiness of some local officials to issue imminent warning and evacuation order. The Haicheng prediction was a success in practice and yielded useful lessons, but the experience cannot be applied to most other earthquakes and cultural environments. Since the disastrous Tangshan earthquake in 1976 that killed over 240,000 people, there have been two opposite trends in China: decreasing confidence in prediction and increasing emphasis on regulating construction design for earthquake resilience. In 1976, most of the seismic intensity XI areas of Tangshan were literally razed to the ground, but in 2008, many buildings in the intensity XI areas of Wenchuan did not collapse. Prediction did not save life in either of these events; the difference was made by construction standards. For regular buildings, there was no seismic design in Tangshan to resist any earthquake shaking in 1976, but limited seismic design was required for the Wenchuan area in 2008. Although the construction standards were later recognized to be too low, those buildings that met the standards suffered much less

  14. Missing great earthquakes

    USGS Publications Warehouse

    Hough, Susan E.

    2013-01-01

    The occurrence of three earthquakes with moment magnitude (Mw) greater than 8.8 and six earthquakes larger than Mw 8.5, since 2004, has raised interest in the long-term global rate of great earthquakes. Past studies have focused on the analysis of earthquakes since 1900, which roughly marks the start of the instrumental era in seismology. Before this time, the catalog is less complete and magnitude estimates are more uncertain. Yet substantial information is available for earthquakes before 1900, and the catalog of historical events is being used increasingly to improve hazard assessment. Here I consider the catalog of historical earthquakes and show that approximately half of all Mw ≥ 8.5 earthquakes are likely missing or underestimated in the 19th century. I further present a reconsideration of the felt effects of the 8 February 1843, Lesser Antilles earthquake, including a first thorough assessment of felt reports from the United States, and show it is an example of a known historical earthquake that was significantly larger than initially estimated. The results suggest that incorporation of best available catalogs of historical earthquakes will likely lead to a significant underestimation of seismic hazard and/or the maximum possible magnitude in many regions, including parts of the Caribbean.

  15. Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake

    USGS Publications Warehouse

    Hayes, Gavin P.; Herman, Matthew W.; Barnhart, William D.; Furlong, Kevin P.; Riquelme, Sebástian; Benz, Harley M.; Bergman, Eric; Barrientos, Sergio; Earle, Paul; Samsonov, Sergey

    2014-01-01

    The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile which had not ruptured in a megathrust earthquake since a M ~8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March–April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

  16. Footprints of past earthquakes revealed in the afterslip of the 2010 Mw 7.8 Mentawai tsunami earthquake

    NASA Astrophysics Data System (ADS)

    Feng, Lujia; Barbot, Sylvain; Hill, Emma M.; Hermawan, Iwan; Banerjee, Paramesh; Natawidjaja, Danny H.

    2016-09-01

    The 2010 Mw 7.8 Mentawai tsunami earthquake marks one of the first tsunami earthquakes to have postseismic deformation observed by geodetic instruments. The Sumatran GPS Array has recorded the postseismic deformation following this event continuously for >5 years. The spatiotemporal evolution of the postseismic deformation is well explained by velocity-strengthening frictional sliding on the Sunda megathrust. Our results show that the 2010 afterslip progressed downdip relative to the 2010 coseismic rupture. The southeastern portion of the afterslip region overlaps the area that slipped during the main shock and afterslip of the 2007 Mw 8.4 Bengkulu earthquake, while the northwestern portion slipped an area without recent large earthquakes. By incorporating pre-earthquake stress conditions into quasi-dynamic models, we demonstrate that the preceding cumulative slip from the 2007 sequence might have caused a ˜0.1 MPa difference in pre-earthquake Coulomb stress between the southeastern and northwestern portions of the afterslip region.

  17. Behavior of the topside ionosphere during earthquakes

    NASA Astrophysics Data System (ADS)

    Maltseva, Olga; Nikitenko, Tatyana; Zhbankov, Gennadii

    2016-07-01

    Investigation of behavior of the ionosphere during earthquakes has long and steady interest. Basically, it concerns to studying behavior of parameters foF2 and hmF2 of the bottomside ionosphere. There are indirect indications of influence of the processes connected with earthquakes on the higher area. Recently, data of measurements of an electron density Ne on low-orbit satellites were appeared over zones of earthquakes. It allows estimating modifications of density Ne in the topside part of the ionosphere. In the present work, N(h)-profiles are calculated with use of the IRI-Plas model and its adaptation not only to experimental values of foF2 and hmF2, but also to the total electron content TEC during periods of earthquakes. Thus in some cases it was possible to adapt model for the plasma frequencies measured on satellites. The cases analyzed in references, concerning, basically, to events in the European and Southeast zones were selected. On an example of a specific case of earthquake on February, 14th 2008 near to Athens, absolute and relative variations of deviations of plasma frequency from a median at various heights (close to hmF2, 400 km, 600 km, 1000 km, 1500 km) are considered for 0 - 12 days before earthquake for various options of adaptation of the model. If to consider that here there can be the variations connected with earthquake, a sign of deviations in most cases was negative with maximum value of magnitude during 8th day before earthquake and in half smaller deviation a day before earthquake. Relative deviations are minimum close hmF2 and maximum at height of 400 km. Since in most cases investigations are fulfilled with a view of search of the precursors, the given work includes the critical analysis of the published and received results. Authors thank Southern Federal University for support by grant #213.01-11/2014-22.

  18. Coping with earthquakes induced by fluid injection

    USGS Publications Warehouse

    McGarr, Arthur F.; Bekins, Barbara; Burkardt, Nina; Dewey, James W.; Earle, Paul; Ellsworth, William L.; Ge, Shemin; Hickman, Stephen H.; Holland, Austin F.; Majer, Ernest; Rubinstein, Justin L.; Sheehan, Anne

    2015-01-01

    Large areas of the United States long considered geologically stable with little or no detected seismicity have recently become seismically active. The increase in earthquake activity began in the mid-continent starting in 2001 (1) and has continued to rise. In 2014, the rate of occurrence of earthquakes with magnitudes (M) of 3 and greater in Oklahoma exceeded that in California (see the figure). This elevated activity includes larger earthquakes, several with M > 5, that have caused significant damage (2, 3). To a large extent, the increasing rate of earthquakes in the mid-continent is due to fluid-injection activities used in modern energy production (1, 4, 5). We explore potential avenues for mitigating effects of induced seismicity. Although the United States is our focus here, Canada, China, the UK, and others confront similar problems associated with oil and gas production, whereas quakes induced by geothermal activities affect Switzerland, Germany, and others.

  19. Safety and survival in an earthquake

    USGS Publications Warehouse

    ,

    1969-01-01

    Many earth scientists in this country and abroad are focusing their studies on the search for means of predicting impending earthquakes, but, as yet, an accurate prediction of the time and place of such an event cannot be made. From past experience, however, one can assume that earthquakes will continue to harass mankind and that they will occur most frequently in the areas where they have been relatively common in the past. In the United States, earthquakes can be expected to occur most frequently in the western states, particularly in Alaska, California, Washington, Oregon, Nevada, Utah, and Montana. The danger, however, is not confined to any one part of the country; major earthquakes have occurred at widely scattered locations.

  20. Disturbances in equilibrium function after major earthquake

    NASA Astrophysics Data System (ADS)

    Honma, Motoyasu; Endo, Nobutaka; Osada, Yoshihisa; Kim, Yoshiharu; Kuriyama, Kenichi

    2012-10-01

    Major earthquakes were followed by a large number of aftershocks and significant outbreaks of dizziness occurred over a large area. However it is unclear why major earthquake causes dizziness. We conducted an intergroup trial on equilibrium dysfunction and psychological states associated with equilibrium dysfunction in individuals exposed to repetitive aftershocks versus those who were rarely exposed. Greater equilibrium dysfunction was observed in the aftershock-exposed group under conditions without visual compensation. Equilibrium dysfunction in the aftershock-exposed group appears to have arisen from disturbance of the inner ear, as well as individual vulnerability to state anxiety enhanced by repetitive exposure to aftershocks. We indicate potential effects of autonomic stress on equilibrium function after major earthquake. Our findings may contribute to risk management of psychological and physical health after major earthquakes with aftershocks, and allow development of a new empirical approach to disaster care after such events.

  1. Disturbances in equilibrium function after major earthquake.

    PubMed

    Honma, Motoyasu; Endo, Nobutaka; Osada, Yoshihisa; Kim, Yoshiharu; Kuriyama, Kenichi

    2012-01-01

    Major earthquakes were followed by a large number of aftershocks and significant outbreaks of dizziness occurred over a large area. However it is unclear why major earthquake causes dizziness. We conducted an intergroup trial on equilibrium dysfunction and psychological states associated with equilibrium dysfunction in individuals exposed to repetitive aftershocks versus those who were rarely exposed. Greater equilibrium dysfunction was observed in the aftershock-exposed group under conditions without visual compensation. Equilibrium dysfunction in the aftershock-exposed group appears to have arisen from disturbance of the inner ear, as well as individual vulnerability to state anxiety enhanced by repetitive exposure to aftershocks. We indicate potential effects of autonomic stress on equilibrium function after major earthquake. Our findings may contribute to risk management of psychological and physical health after major earthquakes with aftershocks, and allow development of a new empirical approach to disaster care after such events.

  2. Geotechnical Extreme Events Reconnaissance Report on the Performance of Structures in Densely Urbanized Areas Affected by Surface Fault Rupture During the August 24, 2014 M6 South Napa Earthquake, California, USA.

    NASA Astrophysics Data System (ADS)

    Cohen-Waeber, J.; Lanzafame, R.; Bray, J.; Sitar, N.

    2014-12-01

    The August 24, 2014, M­w 6.0 South Napa earthquake is the largest seismic event to have occurred in the San Francisco Bay Region, California, USA, since the Mw 6.9 1989 Loma Prieta earthquake. The