WorldWideScience

Sample records for instrumental earthquake studies

  1. Extending the ISC-GEM Global Earthquake Instrumental Catalogue

    Science.gov (United States)

    Di Giacomo, Domenico; Engdhal, Bob; Storchak, Dmitry; Villaseñor, Antonio; Harris, James

    2015-04-01

    After a 27-month project funded by the GEM Foundation (www.globalquakemodel.org), in January 2013 we released the ISC-GEM Global Instrumental Earthquake Catalogue (1900 2009) (www.isc.ac.uk/iscgem/index.php) as a special product to use for seismic hazard studies. The new catalogue was necessary as improved seismic hazard studies necessitate that earthquake catalogues are homogeneous (to the largest extent possible) over time in their fundamental parameters, such as location and magnitude. Due to time and resource limitation, the ISC-GEM catalogue (1900-2009) included earthquakes selected according to the following time-variable cut-off magnitudes: Ms=7.5 for earthquakes occurring before 1918; Ms=6.25 between 1918 and 1963; and Ms=5.5 from 1964 onwards. Because of the importance of having a reliable seismic input for seismic hazard studies, funding from GEM and two commercial companies in the US and UK allowed us to start working on the extension of the ISC-GEM catalogue both for earthquakes that occurred beyond 2009 and for earthquakes listed in the International Seismological Summary (ISS) which fell below the cut-off magnitude of 6.25. This extension is part of a four-year program that aims at including in the ISC-GEM catalogue large global earthquakes that occurred before the beginning of the ISC Bulletin in 1964. In this contribution we present the updated ISC GEM catalogue, which will include over 1000 more earthquakes that occurred in 2010 2011 and several hundreds more between 1950 and 1959. The catalogue extension between 1935 and 1949 is currently underway. The extension of the ISC-GEM catalogue will also be helpful for regional cross border seismic hazard studies as the ISC-GEM catalogue should be used as basis for cross-checking the consistency in location and magnitude of those earthquakes listed both in the ISC GEM global catalogue and regional catalogues.

  2. A study of relay, breaker, instrumentation and control failures during an earthquake, and their effect on nuclear power plant safety

    International Nuclear Information System (INIS)

    Lambert, H.E.; Budnitz, R.J.

    1987-01-01

    In this project, an improved PRA systems analysis methodology for post-earthquake relay-chatter analysis is developed, and its use is demonstrated through analysis of the Zion-1 and LaSalle-2 reactors as case studies. For both Zion-1 and LaSalle-2, assuming that loss of offsite power (LOSP) occurs after a large earthquake and that there are no operator recovery actions, the analysis finds very many combinations (Boolean minimal cut sets) involving chatter of three or four relays and/or pressure switch contacts. The number is so large that there is a very high likelihood (of the order of unity) that at least one combination will occur after earthquake-caused LOSP. This conclusion depends in detail on the fragility curves and response assumptions used for chatter. (orig.)

  3. An instrumental earthquake catalogue for northeastern Italy since 1900

    International Nuclear Information System (INIS)

    Margottini, C.; Martini, G.; Slejko, D.

    1991-01-01

    An earthquake catalogue of instrumental data for northeastern Italy since 1900 is presented. The different types of magnitude, which are the main parameters of the present study, have been evaluated so as to be as homogeneous as possible. Comparisons of the different magnitude values show linear dependence, at least in the medium magnitude range represented by the available data set. Correlations between the magnitude most significant for this region and chosen macroseismic data indicate a methodology for assessing the macroseismic magnitude of historical earthquakes which seems to be stable. (author)

  4. A new reference global instrumental earthquake catalogue (1900-2009)

    Science.gov (United States)

    Di Giacomo, D.; Engdahl, B.; Bondar, I.; Storchak, D. A.; Villasenor, A.; Bormann, P.; Lee, W.; Dando, B.; Harris, J.

    2011-12-01

    For seismic hazard studies on a global and/or regional scale, accurate knowledge of the spatial distribution of seismicity, the magnitude-frequency relation and the maximum magnitudes is of fundamental importance. However, such information is normally not homogeneous (or not available) for the various seismically active regions of the Earth. To achieve the GEM objectives (www.globalquakemodel.org) of calculating and communicating earthquake risk worldwide, an improved reference global instrumental catalogue for large earthquakes spanning the entire 100+ years period of instrumental seismology is an absolute necessity. To accomplish this task, we apply the most up-to-date techniques and standard observatory practices for computing the earthquake location and magnitude. In particular, the re-location procedure benefits both from the depth determination according to Engdahl and Villaseñor (2002), and the advanced technique recently implemented at the ISC (Bondár and Storchak, 2011) to account for correlated error structure. With regard to magnitude, starting from the re-located hypocenters, the classical surface and body-wave magnitudes are determined following the new IASPEI standards and by using amplitude-period data of phases collected from historical station bulletins (up to 1970), which were not available in digital format before the beginning of this work. Finally, the catalogue will provide moment magnitude values (including uncertainty) for each seismic event via seismic moment, via surface wave magnitude or via other magnitude types using empirical relationships. References Engdahl, E.R., and A. Villaseñor (2002). Global seismicity: 1900-1999. In: International Handbook of Earthquake and Engineering Seismology, eds. W.H.K. Lee, H. Kanamori, J.C. Jennings, and C. Kisslinger, Part A, 665-690, Academic Press, San Diego. Bondár, I., and D. Storchak (2011). Improved location procedures at the International Seismological Centre, Geophys. J. Int., doi:10.1111/j

  5. The Landers earthquake; preliminary instrumental results

    Science.gov (United States)

    Jones, L.; Mori, J.; Hauksson, E.

    1992-01-01

    Early on the morning of June 28, 1992, millions of people in southern California were awakened by the largest earthquake to occur in the western United States in the past 40 yrs. At 4:58 a.m PDT (local time), faulting associated with the magnitude 7.3 earthquake broke through to earth's surface near the town of Landers, California. the surface rupture then propagated 70km (45 mi) to the north and northwest along a band of faults passing through the middle of the Mojave Desert. Fortunately, the strongest shaking occurred in uninhabited regions of the Mojave Desert. Still one child was killed in Yucca Valley, and about 400 people were injured in the surrounding area. the desert communities of Landers, Yucca Valley, and Joshua Tree in San Bernardino Country suffered considerable damage to buildings and roads. Damage to water and power lines caused problems in many areas. 

  6. Probabilistic Seismic Hazard Assessment for Himalayan-Tibetan Region from Historical and Instrumental Earthquake Catalogs

    Science.gov (United States)

    Rahman, M. Moklesur; Bai, Ling; Khan, Nangyal Ghani; Li, Guohui

    2018-02-01

    The Himalayan-Tibetan region has a long history of devastating earthquakes with wide-spread casualties and socio-economic damages. Here, we conduct the probabilistic seismic hazard analysis by incorporating the incomplete historical earthquake records along with the instrumental earthquake catalogs for the Himalayan-Tibetan region. Historical earthquake records back to more than 1000 years ago and an updated, homogenized and declustered instrumental earthquake catalog since 1906 are utilized. The essential seismicity parameters, namely, the mean seismicity rate γ, the Gutenberg-Richter b value, and the maximum expected magnitude M max are estimated using the maximum likelihood algorithm assuming the incompleteness of the catalog. To compute the hazard value, three seismogenic source models (smoothed gridded, linear, and areal sources) and two sets of ground motion prediction equations are combined by means of a logic tree on accounting the epistemic uncertainties. The peak ground acceleration (PGA) and spectral acceleration (SA) at 0.2 and 1.0 s are predicted for 2 and 10% probabilities of exceedance over 50 years assuming bedrock condition. The resulting PGA and SA maps show a significant spatio-temporal variation in the hazard values. In general, hazard value is found to be much higher than the previous studies for regions, where great earthquakes have actually occurred. The use of the historical and instrumental earthquake catalogs in combination of multiple seismogenic source models provides better seismic hazard constraints for the Himalayan-Tibetan region.

  7. Empirical relations between instrumental and seismic parameters of some strong earthquakes of Colombia

    International Nuclear Information System (INIS)

    Marin Arias, Juan Pablo; Salcedo Hurtado, Elkin de Jesus; Castillo Gonzalez, Hardany

    2008-01-01

    In order to establish the relationships between macroseismic and instrumental parameters, macroseismic field of 28 historical earthquakes that produced great effects in the Colombian territory were studied. The integration of the parameters was made by using the methodology of Kaussel and Ramirez (1992), for great Chilean earthquakes; Kanamori and Anderson (1975) and Coppersmith and Well (1994) for world-wide earthquakes. Once determined the macroseismic and instrumental parameters it was come to establish the model of the source of each earthquake, with which the data base of these parameters was completed. For each earthquake parameters related to the local and normal macroseismic epicenter were complemented, depth of the local and normal center, horizontal extension of both centers, vertical extension of the normal center, model of the source, area of rupture. The obtained empirical relations from linear equations, even show behaviors very similar to the found ones by other authors for other regions of the world and to world-wide level. The results of this work allow establishing that certain mutual non compatibility exists between the area of rupture and the length of rupture determined by the macroseismic methods, with parameters found with instrumental data like seismic moment, Ms magnitude and Mw magnitude.

  8. Earthquake source properties from instrumented laboratory stick-slip

    Science.gov (United States)

    Kilgore, Brian D.; McGarr, Arthur F.; Beeler, Nicholas M.; Lockner, David A.; Thomas, Marion Y.; Mitchell, Thomas M.; Bhat, Harsha S.

    2017-01-01

    Stick-slip experiments were performed to determine the influence of the testing apparatus on source properties, develop methods to relate stick-slip to natural earthquakes and examine the hypothesis of McGarr [2012] that the product of stiffness, k, and slip duration, Δt, is scale-independent and the same order as for earthquakes. The experiments use the double-direct shear geometry, Sierra White granite at 2 MPa normal stress and a remote slip rate of 0.2 µm/sec. To determine apparatus effects, disc springs were added to the loading column to vary k. Duration, slip, slip rate, and stress drop decrease with increasing k, consistent with a spring-block slider model. However, neither for the data nor model is kΔt constant; this results from varying stiffness at fixed scale.In contrast, additional analysis of laboratory stick-slip studies from a range of standard testing apparatuses is consistent with McGarr's hypothesis. kΔt is scale-independent, similar to that of earthquakes, equivalent to the ratio of static stress drop to average slip velocity, and similar to the ratio of shear modulus to wavespeed of rock. These properties result from conducting experiments over a range of sample sizes, using rock samples with the same elastic properties as the Earth, and scale-independent design practices.

  9. Seismicity map tools for earthquake studies

    Science.gov (United States)

    Boucouvalas, Anthony; Kaskebes, Athanasios; Tselikas, Nikos

    2014-05-01

    We report on the development of new and online set of tools for use within Google Maps, for earthquake research. We demonstrate this server based and online platform (developped with PHP, Javascript, MySQL) with the new tools using a database system with earthquake data. The platform allows us to carry out statistical and deterministic analysis on earthquake data use of Google Maps and plot various seismicity graphs. The tool box has been extended to draw on the map line segments, multiple straight lines horizontally and vertically as well as multiple circles, including geodesic lines. The application is demonstrated using localized seismic data from the geographic region of Greece as well as other global earthquake data. The application also offers regional segmentation (NxN) which allows the studying earthquake clustering, and earthquake cluster shift within the segments in space. The platform offers many filters such for plotting selected magnitude ranges or time periods. The plotting facility allows statistically based plots such as cumulative earthquake magnitude plots and earthquake magnitude histograms, calculation of 'b' etc. What is novel for the platform is the additional deterministic tools. Using the newly developed horizontal and vertical line and circle tools we have studied the spatial distribution trends of many earthquakes and we here show for the first time the link between Fibonacci Numbers and spatiotemporal location of some earthquakes. The new tools are valuable for examining visualizing trends in earthquake research as it allows calculation of statistics as well as deterministic precursors. We plan to show many new results based on our newly developed platform.

  10. Introduction to thematic collection "Historical and geological studies of earthquakes"

    Science.gov (United States)

    Satake, Kenji; Wang, Jian; Hammerl, Christa; Malik, Javed N.

    2017-12-01

    This thematic collection contains eight papers mostly presented at the 2016 AOGS meeting in Beijing. Four papers describe historical earthquake studies in Europe, Japan, and China; one paper uses modern instrumental data to examine the effect of giant earthquakes on the seismicity rate; and three papers describe paleoseismological studies using tsunami deposit in Japan, marine terraces in Philippines, and active faults in Himalayas. Hammerl (Geosci Lett 4:7, 2017) introduced historical seismological studies in Austria, starting from methodology which is state of the art in most European countries, followed by a case study for an earthquake of July 17, 1670 in Tyrol. Albini and Rovida (Geosci Lett 3:30, 2016) examined 114 historical records for the earthquake on April 6, 1667 on the east coast of the Adriatic Sea, compiled 37 Macroseismic Data Points, and estimated the epicenter and the size of the earthquake. Matsu'ura (Geosci Lett 4:3, 2017) summarized historical earthquake studies in Japan which resulted in about 8700 Intensity Data Points, assigned epicenters for 214 earthquakes between AD 599 and 1872, and estimated focal depth and magnitudes for 134 events. Wang et al. (Geosci Lett 4:4, 2017) introduced historical seismology in China, where historical earthquake archives include about 15,000 sources, and parametric catalogs include about 1000 historical earthquakes between 2300 BC and AD 1911. Ishibe et al. (Geosci Lett 4:5, 2017) tested the Coulomb stress triggering hypothesis for three giant (M 9) earthquakes that occurred in recent years, and found that at least the 2004 Sumatra-Andaman and 2011 Tohoku earthquakes caused the seismicity rate change. Ishimura (2017) re-estimated the ages of 11 tsunami deposits in the last 4000 years along the Sanriku coast of northern Japan and found that the average recurrence interval of those tsunamis as 350-390 years. Ramos et al. (2017) studied 1000-year-old marine terraces on the west coast of Luzon Island, Philippines

  11. Update of Earthquake Strong-Motion Instrumentation at Lawrence Livermore National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Robert C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-09-01

    Following the January 1980 earthquake that was felt at Lawrence Livermore National Laboratory (LLNL), a network of strong-motion accelerographs was installed at LLNL. Prior to the 1980 earthquake, there were no accelerographs installed. The ground motion from the 1980 earthquake was estimated from USGS instruments around the Laboratory to be between 0.2 – 0.3 g horizontal peak ground acceleration. These instruments were located at the Veterans Hospital, 5 miles southwest of LLNL, and in San Ramon, about 12 miles west of LLNL. In 2011, the Department of Energy (DOE) requested to know the status of our seismic instruments. We conducted a survey of our instrumentation systems and responded to DOE in a letter. During this survey, it was found that the recorders in Buildings 111 and 332 were not operational. The instruments on Nova had been removed, and only three of the 10 NIF instruments installed in 2005 were operational (two were damaged and five had been removed from operation at the request of the program). After the survey, it was clear that the site seismic instrumentation had degraded substantially and would benefit from an overhaul and more attention to ongoing maintenance. LLNL management decided to update the LLNL seismic instrumentation system. The updated system is documented in this report.

  12. Earthquakes

    Science.gov (United States)

    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 ...

  13. DYFI data for Induced Earthquake Studies

    Data.gov (United States)

    Department of the Interior — The significant rise in seismicity rates in Oklahoma and Kansas (OK–KS) in the last decade has led to an increased interest in studying induced earthquakes. Although...

  14. Studies of the subsurface effects of earthquakes

    International Nuclear Information System (INIS)

    Marine, I.W.

    1980-01-01

    As part of the National Terminal Waste Storage Program, the Savannah River Laboratory is conducting a series of studies on the subsurface effects of earthquakes. This report summarizes three subcontracted studies. (1) Earthquake damage to underground facilities: the purpose of this study was to document damage and nondamage caused by earthquakes to tunnels and shallow underground openings; to mines and other deep openings; and to wells, shafts, and other vertical facilities. (2) Earthquake related displacement fields near underground facilities: the study included an analysis of block motion, an analysis of the dependence of displacement on the orientation and distance of joints from the earthquake source, and displacement related to distance and depth near a causative fault as a result of various shapes, depths, and senses of movement on the causative fault. (3) Numerical simulation of earthquake effects on tunnels for generic nuclear waste repositories: the objective of this study was to use numerical modeling to determine under what conditions seismic waves might cause instability of an underground opening or create fracturing that would increase the permeability of the rock mass

  15. Collaboratory for the Study of Earthquake Predictability

    Science.gov (United States)

    Schorlemmer, D.; Jordan, T. H.; Zechar, J. D.; Gerstenberger, M. C.; Wiemer, S.; Maechling, P. J.

    2006-12-01

    Earthquake prediction is one of the most difficult problems in physical science and, owing to its societal implications, one of the most controversial. The study of earthquake predictability has been impeded by the lack of an adequate experimental infrastructure---the capability to conduct scientific prediction experiments under rigorous, controlled conditions and evaluate them using accepted criteria specified in advance. To remedy this deficiency, the Southern California Earthquake Center (SCEC) is working with its international partners, which include the European Union (through the Swiss Seismological Service) and New Zealand (through GNS Science), to develop a virtual, distributed laboratory with a cyberinfrastructure adequate to support a global program of research on earthquake predictability. This Collaboratory for the Study of Earthquake Predictability (CSEP) will extend the testing activities of SCEC's Working Group on Regional Earthquake Likelihood Models, from which we will present first results. CSEP will support rigorous procedures for registering prediction experiments on regional and global scales, community-endorsed standards for assessing probability-based and alarm-based predictions, access to authorized data sets and monitoring products from designated natural laboratories, and software to allow researchers to participate in prediction experiments. CSEP will encourage research on earthquake predictability by supporting an environment for scientific prediction experiments that allows the predictive skill of proposed algorithms to be rigorously compared with standardized reference methods and data sets. It will thereby reduce the controversies surrounding earthquake prediction, and it will allow the results of prediction experiments to be communicated to the scientific community, governmental agencies, and the general public in an appropriate research context.

  16. The Christchurch earthquake stroke incidence study.

    Science.gov (United States)

    Wu, Teddy Y; Cheung, Jeanette; Cole, David; Fink, John N

    2014-03-01

    We examined the impact of major earthquakes on acute stroke admissions by a retrospective review of stroke admissions in the 6 weeks following the 4 September 2010 and 22 February 2011 earthquakes. The control period was the corresponding 6 weeks in the previous year. In the 6 weeks following the September 2010 earthquake there were 97 acute stroke admissions, with 79 (81.4%) ischaemic infarctions. This was similar to the 2009 control period which had 104 acute stroke admissions, of whom 80 (76.9%) had ischaemic infarction. In the 6 weeks following the February 2011 earthquake, there were 71 stroke admissions, and 61 (79.2%) were ischaemic infarction. This was less than the 96 strokes (72 [75%] ischaemic infarction) in the corresponding control period. None of the comparisons were statistically significant. There was also no difference in the rate of cardioembolic infarction from atrial fibrillation between the study periods. Patients admitted during the February 2011 earthquake period were less likely to be discharged directly home when compared to the control period (31.2% versus 46.9%, p=0.036). There was no observable trend in the number of weekly stroke admissions between the 2 weeks leading to and 6 weeks following the earthquakes. Our results suggest that severe psychological stress from earthquakes did not influence the subsequent short term risk of acute stroke, but the severity of the earthquake in February 2011 and associated civil structural damages may have influenced the pattern of discharge for stroke patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Experimental study of structural response to earthquakes

    International Nuclear Information System (INIS)

    Clough, R.W.; Bertero, V.V.; Bouwkamp, J.G.; Popov, E.P.

    1975-01-01

    The objectives, methods, and some of the principal results obtained from experimental studies of the behavior of structures subjected to earthquakes are described. Although such investigations are being conducted in many laboratories throughout the world, the information presented deals specifically with projects being carried out at the Earthquake Engineering Research Center (EERC) of the University of California, Berkeley. A primary purpose of these investigations is to obtain detailed information on the inelastic response mechanisms in typical structural systems so that the experimentally observed performance can be compared with computer generated analytical predictions. Only by such comparisons can the mathematical models used in dynamic nonlinear analyses be verified and improved. Two experimental procedures for investigating earthquake structural response are discussed: the earthquake simulator facility which subjects the base of the test structure to acceleration histories similar to those recorded in actual earthquakes, and systems of hydraulic rams which impose specified displacement histories on the test components, equivalent to motions developed in structures subjected to actual'quakes. The general concept and performance of the 20ft square EERC earthquake simulator is described, and the testing of a two story concrete frame building is outlined. Correlation of the experimental results with analytical predictions demonstrates that satisfactory agreement can be obtained only if the mathematical model incorporates a stiffness deterioration mechanism which simulates the cracking and other damage suffered by the structure

  18. Validation of Atmosphere/Ionosphere Signals Associated with Major Earthquakes by Multi-Instrument Space-Borne and Ground Observations

    Science.gov (United States)

    Ouzounov, Dimitar; Pulinets, Sergey; Hattori, Katsumi; Parrot, Michel; Liu, J. Y.; Yang, T. F.; Arellano-Baeza, Alonso; Kafatos, M.; Taylor, Patrick

    2012-01-01

    The latest catastrophic earthquake in Japan (March 2011) has renewed interest in the important question of the existence of pre-earthquake anomalous signals related to strong earthquakes. Recent studies have shown that there were precursory atmospheric/ionospheric signals observed in space associated with major earthquakes. The critical question, still widely debated in the scientific community, is whether such ionospheric/atmospheric signals systematically precede large earthquakes. To address this problem we have started to investigate anomalous ionospheric / atmospheric signals occurring prior to large earthquakes. We are studying the Earth's atmospheric electromagnetic environment by developing a multisensor model for monitoring the signals related to active tectonic faulting and earthquake processes. The integrated satellite and terrestrial framework (ISTF) is our method for validation and is based on a joint analysis of several physical and environmental parameters (thermal infrared radiation, electron concentration in the ionosphere, lineament analysis, radon/ion activities, air temperature and seismicity) that were found to be associated with earthquakes. A physical link between these parameters and earthquake processes has been provided by the recent version of Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model. Our experimental measurements have supported the new theoretical estimates of LAIC hypothesis for an increase in the surface latent heat flux, integrated variability of outgoing long wave radiation (OLR) and anomalous variations of the total electron content (TEC) registered over the epicenters. Some of the major earthquakes are accompanied by an intensification of gas migration to the surface, thermodynamic and hydrodynamic processes of transformation of latent heat into thermal energy and with vertical transport of charged aerosols in the lower atmosphere. These processes lead to the generation of external electric currents in specific

  19. 78 FR 19004 - Scientific Earthquake Studies Advisory Committee

    Science.gov (United States)

    2013-03-28

    ... Hazards Program. Focus topics for this meeting include induced seismicity, earthquake early warning and... DEPARTMENT OF THE INTERIOR U.S. Geological Survey [GX13GG009950000] Scientific Earthquake Studies... Law 106-503, the Scientific Earthquake Studies Advisory Committee (SESAC) will hold its next meeting...

  20. 78 FR 64973 - Scientific Earthquake Studies Advisory Committee (SESAC)

    Science.gov (United States)

    2013-10-30

    ... DEPARTMENT OF THE INTERIOR Geological Survey [GX14GG009950000] Scientific Earthquake Studies... Public Law 106-503, the Scientific Earthquake Studies Advisory Committee (SESAC) will hold its next... Survey (USGS) on matters relating to the USGS's participation in the National Earthquake Hazards...

  1. 75 FR 2159 - Scientific Earthquake Studies Advisory Committee

    Science.gov (United States)

    2010-01-14

    ... DEPARTMENT OF THE INTERIOR U.S. Geological Survey Scientific Earthquake Studies Advisory Committee... Scientific Earthquake Studies Advisory Committee (SESAC) will hold its next meeting at the U.S. Geological... participation in the National Earthquake Hazards Reduction Program. The Committee will receive updates and...

  2. Earthquake Damage Assessment Using Objective Image Segmentation: A Case Study of 2010 Haiti Earthquake

    Science.gov (United States)

    Oommen, Thomas; Rebbapragada, Umaa; Cerminaro, Daniel

    2012-01-01

    In this study, we perform a case study on imagery from the Haiti earthquake that evaluates a novel object-based approach for characterizing earthquake induced surface effects of liquefaction against a traditional pixel based change technique. Our technique, which combines object-oriented change detection with discriminant/categorical functions, shows the power of distinguishing earthquake-induced surface effects from changes in buildings using the object properties concavity, convexity, orthogonality and rectangularity. Our results suggest that object-based analysis holds promise in automatically extracting earthquake-induced damages from high-resolution aerial/satellite imagery.

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

    Science.gov (United States)

    Zoeller, G.

    2017-12-01

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

  4. 75 FR 66388 - Scientific Earthquake Studies Advisory Committee

    Science.gov (United States)

    2010-10-28

    ..., including the multi-hazards demonstration project and earthquake early warning prototype development. The... DEPARTMENT OF THE INTERIOR U.S. Geological Survey [USGS-GX11GG009950000] Scientific Earthquake... Public Law 106-503, the Scientific Earthquake Studies Advisory Committee (SESAC) will hold its next...

  5. The Challenge of Centennial Earthquakes to Improve Modern Earthquake Engineering

    International Nuclear Information System (INIS)

    Saragoni, G. Rodolfo

    2008-01-01

    The recent commemoration of the centennial of the San Francisco and Valparaiso 1906 earthquakes has given the opportunity to reanalyze their damages from modern earthquake engineering perspective. These two earthquakes plus Messina Reggio Calabria 1908 had a strong impact in the birth and developing of earthquake engineering. The study of the seismic performance of some up today existing buildings, that survive centennial earthquakes, represent a challenge to better understand the limitations of our in use earthquake design methods. Only Valparaiso 1906 earthquake, of the three considered centennial earthquakes, has been repeated again as the Central Chile, 1985, Ms = 7.8 earthquake. In this paper a comparative study of the damage produced by 1906 and 1985 Valparaiso earthquakes is done in the neighborhood of Valparaiso harbor. In this study the only three centennial buildings of 3 stories that survived both earthquakes almost undamaged were identified. Since for 1985 earthquake accelerogram at El Almendral soil conditions as well as in rock were recoded, the vulnerability analysis of these building is done considering instrumental measurements of the demand. The study concludes that good performance of these buildings in the epicentral zone of large earthquakes can not be well explained by modern earthquake engineering methods. Therefore, it is recommended to use in the future of more suitable instrumental parameters, such as the destructiveness potential factor, to describe earthquake demand

  6. Radon anomalies prior to earthquakes (1). Review of previous studies

    International Nuclear Information System (INIS)

    Ishikawa, Tetsuo; Tokonami, Shinji; Yasuoka, Yumi; Shinogi, Masaki; Nagahama, Hiroyuki; Omori, Yasutaka; Kawada, Yusuke

    2008-01-01

    The relationship between radon anomalies and earthquakes has been studied for more than 30 years. However, most of the studies dealt with radon in soil gas or in groundwater. Before the 1995 Hyogoken-Nanbu earthquake, an anomalous increase of atmospheric radon was observed at Kobe Pharmaceutical University. The increase was well fitted with a mathematical model related to earthquake fault dynamics. This paper reports the significance of this observation, reviewing previous studies on radon anomaly before earthquakes. Groundwater/soil radon measurements for earthquake prediction began in 1970's in Japan as well as foreign countries. One of the most famous studies in Japan is groundwater radon anomaly before the 1978 Izu-Oshima-kinkai earthquake. We have recognized the significance of radon in earthquake prediction research, but recently its limitation was also pointed out. Some researchers are looking for a better indicator for precursors; simultaneous measurements of radon and other gases are new trials in recent studies. Contrary to soil/groundwater radon, we have not paid much attention to atmospheric radon before earthquakes. However, it might be possible to detect precursors in atmospheric radon before a large earthquake. In the next issues, we will discuss the details of the anomalous atmospheric radon data observed before the Hyogoken-Nanbu earthquake. (author)

  7. Biological Indicators in Studies of Earthquake Precursors

    Science.gov (United States)

    Sidorin, A. Ya.; Deshcherevskii, A. V.

    2012-04-01

    Time series of data on variations in the electric activity (EA) of four species of weakly electric fish Gnathonemus leopoldianus and moving activity (MA) of two cat-fishes Hoplosternum thoracatum and two groups of Columbian cockroaches Blaberus craniifer were analyzed. The observations were carried out in the Garm region of Tajikistan within the frameworks of the experiments aimed at searching for earthquake precursors. An automatic recording system continuously recorded EA and DA over a period of several years. Hourly means EA and MA values were processed. Approximately 100 different parameters were calculated on the basis of six initial EA and MA time series, which characterize different variations in the EA and DA structure: amplitude of the signal and fluctuations of activity, parameters of diurnal rhythms, correlated changes in the activity of various biological indicators, and others. A detailed analysis of the statistical structure of the total array of parametric time series obtained in the experiment showed that the behavior of all animals shows a strong temporal variability. All calculated parameters are unstable and subject to frequent changes. A comparison of the data obtained with seismicity allow us to make the following conclusions: (1) The structure of variations in the studied parameters is represented by flicker noise or even a more complex process with permanent changes in its characteristics. Significant statistics are required to prove the cause-and-effect relationship of the specific features of such time series with seismicity. (2) The calculation of the reconstruction statistics in the EA and MA series structure demonstrated an increase in their frequency in the last hours or a few days before the earthquake if the hypocenter distance is comparable to the source size. Sufficiently dramatic anomalies in the behavior of catfishes and cockroaches (changes in the amplitude of activity variation, distortions of diurnal rhythms, increase in the

  8. A Case Study of the Bam Earthquake to Establish a Pattern for Earthquake Management in Iran

    Directory of Open Access Journals (Sweden)

    Keramatollah Ziari

    2015-03-01

    Full Text Available The field of crisis management knowledge and expertise is associated with a wide range of fields. Knowledge-based crisis management is a combination of science, art and practice. Iran is an earthquake-prone country. Through years several earthquakes have happened in the country resulting in many human and financial losses. According to scientific standards, the first 24 hours following an earthquake is the most valuable time for saving victims. Yet in the case of Bam only 5% of the victims were rescued within the first 48 hours. The success of disaster management is evaluated in terms of programming, raising public participation, organizing and hiring manpower, and supervising the management process. In this study disaster management is divided into three stages in which different actions are required. The stages and actions are explained in detail. Moreover, features, effects, and losses of the earthquake are described.

  9. Database for earthquake strong motion studies in Italy

    Science.gov (United States)

    Scasserra, G.; Stewart, J.P.; Kayen, R.E.; Lanzo, G.

    2009-01-01

    We describe an Italian database of strong ground motion recordings and databanks delineating conditions at the instrument sites and characteristics of the seismic sources. The strong motion database consists of 247 corrected recordings from 89 earthquakes and 101 recording stations. Uncorrected recordings were drawn from public web sites and processed on a record-by-record basis using a procedure utilized in the Next-Generation Attenuation (NGA) project to remove instrument resonances, minimize noise effects through low- and high-pass filtering, and baseline correction. The number of available uncorrected recordings was reduced by 52% (mostly because of s-triggers) to arrive at the 247 recordings in the database. The site databank includes for every recording site the surface geology, a measurement or estimate of average shear wave velocity in the upper 30 m (Vs30), and information on instrument housing. Of the 89 sites, 39 have on-site velocity measurements (17 of which were performed as part of this study using SASW techniques). For remaining sites, we estimate Vs30 based on measurements on similar geologic conditions where available. Where no local velocity measurements are available, correlations with surface geology are used. Source parameters are drawn from databanks maintained (and recently updated) by Istituto Nazionale di Geofisica e Vulcanologia and include hypocenter location and magnitude for small events (M< ??? 5.5) and finite source parameters for larger events. ?? 2009 A.S. Elnashai & N.N. Ambraseys.

  10. Earthquake Source Spectral Study beyond the Omega-Square Model

    Science.gov (United States)

    Uchide, T.; Imanishi, K.

    2017-12-01

    Earthquake source spectra have been used for characterizing earthquake source processes quantitatively and, at the same time, simply, so that we can analyze the source spectra for many earthquakes, especially for small earthquakes, at once and compare them each other. A standard model for the source spectra is the omega-square model, which has the flat spectrum and the falloff inversely proportional to the square of frequencies at low and high frequencies, respectively, which are bordered by a corner frequency. The corner frequency has often been converted to the stress drop under the assumption of circular crack models. However, recent studies claimed the existence of another corner frequency [Denolle and Shearer, 2016; Uchide and Imanishi, 2016] thanks to the recent development of seismic networks. We have found that many earthquakes in areas other than the area studied by Uchide and Imanishi [2016] also have source spectra deviating from the omega-square model. Another part of the earthquake spectra we now focus on is the falloff rate at high frequencies, which will affect the seismic energy estimation [e.g., Hirano and Yagi, 2017]. In June, 2016, we deployed seven velocity seismometers in the northern Ibaraki prefecture, where the shallow crustal seismicity mainly with normal-faulting events was activated by the 2011 Tohoku-oki earthquake. We have recorded seismograms at 1000 samples per second and at a short distance from the source, so that we can investigate the high-frequency components of the earthquake source spectra. Although we are still in the stage of discovery and confirmation of the deviation from the standard omega-square model, the update of the earthquake source spectrum model will help us systematically extract more information on the earthquake source process.

  11. Earthquake forecasting studies using radon time series data in Taiwan

    Science.gov (United States)

    Walia, Vivek; Kumar, Arvind; Fu, Ching-Chou; Lin, Shih-Jung; Chou, Kuang-Wu; Wen, Kuo-Liang; Chen, Cheng-Hong

    2017-04-01

    For few decades, growing number of studies have shown usefulness of data in the field of seismogeochemistry interpreted as geochemical precursory signals for impending earthquakes and radon is idendified to be as one of the most reliable geochemical precursor. Radon is recognized as short-term precursor and is being monitored in many countries. This study is aimed at developing an effective earthquake forecasting system by inspecting long term radon time series data. The data is obtained from a network of radon monitoring stations eastblished along different faults of Taiwan. The continuous time series radon data for earthquake studies have been recorded and some significant variations associated with strong earthquakes have been observed. The data is also examined to evaluate earthquake precursory signals against environmental factors. An automated real-time database operating system has been developed recently to improve the data processing for earthquake precursory studies. In addition, the study is aimed at the appraisal and filtrations of these environmental parameters, in order to create a real-time database that helps our earthquake precursory study. In recent years, automatic operating real-time database has been developed using R, an open source programming language, to carry out statistical computation on the data. To integrate our data with our working procedure, we use the popular and famous open source web application solution, AMP (Apache, MySQL, and PHP), creating a website that could effectively show and help us manage the real-time database.

  12. THEORETICAL AND EXPERIMENTAL STUDY OF STRUCTURES SUBJECTED TO EARTHQUAKES

    Energy Technology Data Exchange (ETDEWEB)

    Soubirou, A.

    1967-12-31

    The object of the study was the investigation of the behaviour of structures subject to earthquakes. After .describing and analysing seismic movements, useful concepts for earthquake-proofing structures are lintroduced. Then, the dynamic behaviour of systems with n degrees of freedom was studied in order to evolve the theoretical computation of seismic behaviour, a typical application being reticulated structures. The next stage was showing the computational procedure for seismic spectra and the natural frequencies of buildings, an attempt being made to define earthquake-proofing criteria for a special type of reinforced-concrete construction. . The last matter dealt with is elastoplastic behaviour of structures, a study of increasingly growing importance.

  13. An interdisciplinary approach to study Pre-Earthquake processes

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S. A.; Hattori, K.; Taylor, P. T.

    2017-12-01

    We will summarize a multi-year research effort on wide-ranging observations of pre-earthquake processes. Based on space and ground data we present some new results relevant to the existence of pre-earthquake signals. Over the past 15-20 years there has been a major revival of interest in pre-earthquake studies in Japan, Russia, China, EU, Taiwan and elsewhere. Recent large magnitude earthquakes in Asia and Europe have shown the importance of these various studies in the search for earthquake precursors either for forecasting or predictions. Some new results were obtained from modeling of the atmosphere-ionosphere connection and analyses of seismic records (foreshocks /aftershocks), geochemical, electromagnetic, and thermodynamic processes related to stress changes in the lithosphere, along with their statistical and physical validation. This cross - disciplinary approach could make an impact on our further understanding of the physics of earthquakes and the phenomena that precedes their energy release. We also present the potential impact of these interdisciplinary studies to earthquake predictability. A detail summary of our approach and that of several international researchers will be part of this session and will be subsequently published in a new AGU/Wiley volume. This book is part of the Geophysical Monograph series and is intended to show the variety of parameters seismic, atmospheric, geochemical and historical involved is this important field of research and will bring this knowledge and awareness to a broader geosciences community.

  14. Overestimation of the earthquake hazard along the Himalaya: constraints in bracketing of medieval earthquakes from paleoseismic studies

    Science.gov (United States)

    Arora, Shreya; Malik, Javed N.

    2017-12-01

    The Himalaya is one of the most seismically active regions of the world. The occurrence of several large magnitude earthquakes viz. 1905 Kangra earthquake (Mw 7.8), 1934 Bihar-Nepal earthquake (Mw 8.2), 1950 Assam earthquake (Mw 8.4), 2005 Kashmir (Mw 7.6), and 2015 Gorkha (Mw 7.8) are the testimony to ongoing tectonic activity. In the last few decades, tremendous efforts have been made along the Himalayan arc to understand the patterns of earthquake occurrences, size, extent, and return periods. Some of the large magnitude earthquakes produced surface rupture, while some remained blind. Furthermore, due to the incompleteness of the earthquake catalogue, a very few events can be correlated with medieval earthquakes. Based on the existing paleoseismic data certainly, there exists a complexity to precisely determine the extent of surface rupture of these earthquakes and also for those events, which occurred during historic times. In this paper, we have compiled the paleo-seismological data and recalibrated the radiocarbon ages from the trenches excavated by previous workers along the entire Himalaya and compared earthquake scenario with the past. Our studies suggest that there were multiple earthquake events with overlapping surface ruptures in small patches with an average rupture length of 300 km limiting Mw 7.8-8.0 for the Himalayan arc, rather than two or three giant earthquakes rupturing the whole front. It has been identified that the large magnitude Himalayan earthquakes, such as 1905 Kangra, 1934 Bihar-Nepal, and 1950 Assam, that have occurred within a time frame of 45 years. Now, if these events are dated, there is a high possibility that within the range of ±50 years, they may be considered as the remnant of one giant earthquake rupturing the entire Himalayan arc. Therefore, leading to an overestimation of seismic hazard scenario in Himalaya.

  15. Ionospheric precursors to large earthquakes: A case study of the 2011 Japanese Tohoku Earthquake

    Science.gov (United States)

    Carter, B. A.; Kellerman, A. C.; Kane, T. A.; Dyson, P. L.; Norman, R.; Zhang, K.

    2013-09-01

    Researchers have reported ionospheric electron distribution abnormalities, such as electron density enhancements and/or depletions, that they claimed were related to forthcoming earthquakes. In this study, the Tohoku earthquake is examined using ionosonde data to establish whether any otherwise unexplained ionospheric anomalies were detected in the days and hours prior to the event. As the choices for the ionospheric baseline are generally different between previous works, three separate baselines for the peak plasma frequency of the F2 layer, foF2, are employed here; the running 30-day median (commonly used in other works), the International Reference Ionosphere (IRI) model and the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIE-GCM). It is demonstrated that the classification of an ionospheric perturbation is heavily reliant on the baseline used, with the 30-day median, the IRI and the TIE-GCM generally underestimating, approximately describing and overestimating the measured foF2, respectively, in the 1-month period leading up to the earthquake. A detailed analysis of the ionospheric variability in the 3 days before the earthquake is then undertaken, where a simultaneous increase in foF2 and the Es layer peak plasma frequency, foEs, relative to the 30-day median was observed within 1 h before the earthquake. A statistical search for similar simultaneous foF2 and foEs increases in 6 years of data revealed that this feature has been observed on many other occasions without related seismic activity. Therefore, it is concluded that one cannot confidently use this type of ionospheric perturbation to predict an impending earthquake. It is suggested that in order to achieve significant progress in our understanding of seismo-ionospheric coupling, better account must be taken of other known sources of ionospheric variability in addition to solar and geomagnetic activity, such as the thermospheric coupling.

  16. Earthquake correlations and networks: A comparative study

    Science.gov (United States)

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

    2011-04-01

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

  17. Earthquake correlations and networks: A comparative study

    International Nuclear Information System (INIS)

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

    2011-01-01

    We quantify the correlation between earthquakes and use the same to extract causally connected earthquake pairs. Our correlation metric is a variation on the one introduced by Baiesi and Paczuski [M. Baiesi and M. Paczuski, Phys. Rev. E 69, 066106 (2004)]. A network of earthquakes is then constructed from the time-ordered catalog and with links between the more correlated ones. A list of recurrences to each of the earthquakes is identified employing correlation thresholds to demarcate the most meaningful ones in each cluster. Data pertaining to three different seismic regions (viz., California, Japan, and the Himalayas) are comparatively analyzed using such a network model. The distribution of recurrence lengths and recurrence times are two of the key features analyzed to draw conclusions about the universal aspects of such a network model. We find that the unimodal feature of recurrence length distribution, which helps to associate typical rupture lengths with different magnitude earthquakes, is robust across the different seismic regions. The out-degree of the networks shows a hub structure rooted on the large magnitude earthquakes. In-degree distribution is seen to be dependent on the density of events in the neighborhood. Power laws, with two regimes having different exponents, are obtained with recurrence time distribution. The first regime confirms the Omori law for aftershocks while the second regime, with a faster falloff for the larger recurrence times, establishes that pure spatial recurrences also follow a power-law distribution. The crossover to the second power-law regime can be taken to be signaling the end of the aftershock regime in an objective fashion.

  18. MUG-OBS - Multiparameter Geophysical Ocean Bottom System : a new instrumental approach to monitor earthquakes.

    Science.gov (United States)

    hello, yann; Charvis, Philippe; Yegikyan, Manuk; verfaillie, Romain; Rivet, Diane

    2016-04-01

    Real time monitoring of seismic activity is a major issue for early warning of earthquakes and tsunamis. It can be done using regional scale wired nodes, such as Neptune in Canada and in the U.S, or DONET in Japan. Another approach to monitor seismic activity at sea is to deploying repeatedly OBS array like during the amphibious Cascadia Initiative (four time 1-year deployments), the Japanese Pacific Array (broadband OBSs "ocean-bottom broadband dispersion survey" with 2-years autonomy), the Obsismer program in the French Lesser Antilles (eight time 6-months deployments) and the Osisec program in Ecuador (four time 6-months deployments). These autonomous OBSs are self-recovered or recovered using an ROV. These systems are costly including ship time, and require to recover the OBS before to start working on data. Among the most recent alternative we developed a 3/4 years autonomy ocean bottom system with 9 channels (?) allowing the acquisition of different seismic or environmental parameters. MUG-OBS is a free falling instrument rated down to 6000 m. The installation of the sensor is monitored by acoustic commands from the surface and a health bulletin with data checking is recovered by acoustic during the installation. The major innovation is that it is possible to recover the data any time on demand (regularly every 6-months or after a crisis) using one of the 6 data-shuttles released from the surface by acoustic command using a one day fast cruise boat of opportunity. Since sensors stayed at the same location for 3 years, it is a perfect tool to monitor large seismic events, background seismic activity and aftershock distribution. Clock, drift measurement and GPS localization is automatic when the shuttle reaches the surface. For remote areas, shuttles released automatically and a seismic events bulletin is transmitted. Selected data can be recovered by two-way Iridium satellite communication. After a period of 3 years the main station is self-recovered by

  19. Data base and seismicity studies for Fagaras, Romania crustal earthquakes

    International Nuclear Information System (INIS)

    Moldovan, I.-A.; Enescu, B. D.; Pantea, A.; Constantin, A.; Bazacliu, O.; Malita, Z.; Moldoveanu, T.

    2002-01-01

    Besides the major impact of the Vrancea seismic region, one of the most important intermediate earthquake sources of Europe, the Romanian crustal earthquake sources, from Fagaras, Banat, Crisana, Bucovina or Dobrogea regions, have to be taken into consideration for seismicity studies or seismic hazard assessment. To determine the characteristics of the seismicity for Fagaras seismogenic region, a revised and updated catalogue of the Romanian earthquakes, recently compiled by Oncescu et al. (1999) is used. The catalogue contains 471 tectonic earthquakes and 338 induced earthquakes and is homogenous starting with 1471 for I>VIII and for I>VII starting with 1801. The catalogue is complete for magnitudes larger than 3 starting with 1982. In the studied zone only normal earthquakes occur, related to intracrustal fractures situated from 5 to 30 km depth. Most of them are of low energy, but once in a century a large destructive event occurs with epicentral intensity larger than VIII. The maximum expected magnitude is M GR = 6.5 and the epicenter distribution outlines significant clustering in the zones and on the lines mentioned in the tectonic studies. Taking into account the date of the last major earthquake (1916) and the return periods of severe damaging shocks of over 85 years it is to be expected very soon a large shock in the area. That's why a seismicity and hazard study for this zone is necessary. In the paper there are studied the b parameter variation (the mean value is 0.69), the activity value, the return periods, and seismicity maps and different histograms are plotted. At the same time there are excluded from the catalogue the explosions due to Campulung quarry. Because the catalogue contains the aftershocks for the 1916 earthquake for the seismicity studies we have excluded these shocks. (authors)

  20. 14 April 1895, Ljubljana earthquake - A new, cross-border study

    Science.gov (United States)

    Albini, Paola; Cecić, Ina; Hammerl, Christa

    2014-05-01

    Though it has been the object of both contemporary and modern investigations, the 14 April 1895, Ljubljana event (Mw ~6, according to the European catalogue SHEEC) is still not fully described in its effects. One manifest reason for this is that being the 1895 earthquake a cross-border event, it affected an area that today pertains to three different countries, Slovenia, Austria, and Italy, as well as accounted for in sources today scattered in different archives and libraries. In addition, the 1895 Ljubljana earthquake was a turning point for many aspects. Imperial Vienna sent help to rebuild the damaged city and its surroundings, and the architects brought modern ideas about urban planning, public hygiene and contemporary design. It was also the beginning of organised seismological observations in Slovenia - macroseismic, right after the earthquake, and instrumental, in 1896. The macroseismic data about this earthquake are plentiful and very well preserved. In this new, cross-border study we intend to re-evaluate the already known as well as the newly collected data sources. Specific attention is devoted to the archival documentation on damage, and to the far-field data, which were not comprehensively taken into account beforehand. As the earthquake was felt in a large part of central and Eastern Europe, a considerable effort is put into collecting and interpreting the coeval sources, written in many different languages.

  1. Earthquakes of Garhwal Himalaya region of NW Himalaya, India: A study of relocated earthquakes and their seismogenic source and stress

    Science.gov (United States)

    R, A. P.; Paul, A.; Singh, S.

    2017-12-01

    Since the continent-continent collision 55 Ma, the Himalaya has accommodated 2000 km of convergence along its arc. The strain energy is being accumulated at a rate of 37-44 mm/yr and releases at time as earthquakes. The Garhwal Himalaya is located at the western side of a Seismic Gap, where a great earthquake is overdue atleast since 200 years. This seismic gap (Central Seismic Gap: CSG) with 52% probability for a future great earthquake is located between the rupture zones of two significant/great earthquakes, viz. the 1905 Kangra earthquake of M 7.8 and the 1934 Bihar-Nepal earthquake of M 8.0; and the most recent one, the 2015 Gorkha earthquake of M 7.8 is in the eastern side of this seismic gap (CSG). The Garhwal Himalaya is one of the ideal locations of the Himalaya where all the major Himalayan structures and the Himalayan Seimsicity Belt (HSB) can ably be described and studied. In the present study, we are presenting the spatio-temporal analysis of the relocated local micro-moderate earthquakes, recorded by a seismicity monitoring network, which is operational since, 2007. The earthquake locations are relocated using the HypoDD (double difference hypocenter method for earthquake relocations) program. The dataset from July, 2007- September, 2015 have been used in this study to estimate their spatio-temporal relationships, moment tensor (MT) solutions for the earthquakes of M>3.0, stress tensors and their interactions. We have also used the composite focal mechanism solutions for small earthquakes. The majority of the MT solutions show thrust type mechanism and located near the mid-crustal-ramp (MCR) structure of the detachment surface at 8-15 km depth beneath the outer lesser Himalaya and higher Himalaya regions. The prevailing stress has been identified to be compressional towards NNE-SSW, which is the direction of relative plate motion between the India and Eurasia continental plates. The low friction coefficient estimated along with the stress inversions

  2. The Preliminary Study of the 4 March 2010 Mw 6.3 Jiasian, Taiwan Earthquake Sequence

    Directory of Open Access Journals (Sweden)

    Hsin-Hua Huang

    2011-01-01

    Full Text Available On 4 March 2010, an inland Mw 6.3 earthquake occurred near the town of Jiasian in Kaohsiung County, Taiwan causing large ground shaking and extensive damage. In this study, we integrate the records from the Central Weather Bureau Seismic Network (CWBSN and Taiwan Strong Motion Instrumentation Program (TSMIP to obtain the relocated earthquake sequence and its first-motion focal mechanisms. This dataset offers us precise and reliable results which suggest a focal depth of 23 km and a possible fault plane of strike 313¢X, dip 41¢X, and rake 42¢X for the Jiasian earthquake. This fault plane significantly differs from the N-S striking Chaochou Fault (CCF as well as the principal trend of Taiwan orogenic belt, and should be an undiscovered fault in southern Taiwan. The relocated Jiasian earthquake sequence initiating from the 23-km-deep mainshock and terminating at around 10 km in depth also indicates it is a blind fault. Peak ground acceleration (PGA and peak ground velocity (PGV recorded by the TSMIP stations reveal a distinct NW-SE-shape pattern from the epicenter area toward the Chiayi region, likely due to the directivity and site effects. Such phenomena should be considered for future regional hazard assessments.

  3. Feasibility study of earthquake early warning (EEW) in Hawaii

    Science.gov (United States)

    Thelen, Weston A.; Hotovec-Ellis, Alicia J.; Bodin, Paul

    2016-09-30

    when using a regional network of seismometers. Given the current network, a single-station approach provides more warning for damaging earthquakes that occur close to the station, but it would have limited benefit compared to a fully implemented ShakeAlert system. For Honolulu, for example, the single-station approach provides an advantage over ShakeAlert only for earthquakes that occur in a narrow zone extending northeast and southwest of O‘ahu. Instrumentation and alarms associated with the single-station approach are typically maintained and assessed within the target facility, and thus no outside connectivity is required. A single-station approach, then, is unlikely to help broader populations beyond the individuals at the target facility, but they have the benefit of being commercially available for relatively little cost. The USGS Hawaiian Volcano Observatory (HVO) is the Advanced National Seismic System (ANSS) regional seismic network responsible for locating and characterizing earthquakes across the State of Hawaii. During 2014 and 2015, HVO tested a network-based EEW algorithm within the current seismic network in order to assess the suitability for building a full EEW system. Using the current seismic instrumentation and processing setup at HVO, it is possible for a network approach to release an alarm a little more than 3 seconds after the earthquake is recorded on the fourth seismometer. Presently, earthquakes having M≥3 detected with the ElarmS algorithm have an average location error of approximately 4.5 km and an average magnitude error of -0.3 compared to the reviewed catalog locations from the HVO. Additional stations and upgrades to existing seismic stations would serve to improve solution precision and warning times and additional staffing would be required to provide support for a robust, network-based EEW system. For a critical facility on the Island of Hawaiʻi, such as the telescopes atop Mauna Kea, one phased approach to mitigate losses

  4. Earthquake hazard evaluation for Switzerland

    International Nuclear Information System (INIS)

    Ruettener, E.

    1995-01-01

    Earthquake hazard analysis is of considerable importance for Switzerland, a country with moderate seismic activity but high economic values at risk. The evaluation of earthquake hazard, i.e. the determination of return periods versus ground motion parameters, requires a description of earthquake occurrences in space and time. In this study the seismic hazard for major cities in Switzerland is determined. The seismic hazard analysis is based on historic earthquake records as well as instrumental data. The historic earthquake data show considerable uncertainties concerning epicenter location and epicentral intensity. A specific concept is required, therefore, which permits the description of the uncertainties of each individual earthquake. This is achieved by probability distributions for earthquake size and location. Historical considerations, which indicate changes in public earthquake awareness at various times (mainly due to large historical earthquakes), as well as statistical tests have been used to identify time periods of complete earthquake reporting as a function of intensity. As a result, the catalog is judged to be complete since 1878 for all earthquakes with epicentral intensities greater than IV, since 1750 for intensities greater than VI, since 1600 for intensities greater than VIII, and since 1300 for intensities greater than IX. Instrumental data provide accurate information about the depth distribution of earthquakes in Switzerland. In the Alps, focal depths are restricted to the uppermost 15 km of the crust, whereas below the northern Alpine foreland earthquakes are distributed throughout the entire crust (30 km). This depth distribution is considered in the final hazard analysis by probability distributions. (author) figs., tabs., refs

  5. Historical earthquake research in Austria

    Science.gov (United States)

    Hammerl, Christa

    2017-12-01

    Austria has a moderate seismicity, and on average the population feels 40 earthquakes per year or approximately three earthquakes per month. A severe earthquake with light building damage is expected roughly every 2 to 3 years in Austria. Severe damage to buildings ( I 0 > 8° EMS) occurs significantly less frequently, the average period of recurrence is about 75 years. For this reason the historical earthquake research has been of special importance in Austria. The interest in historical earthquakes in the past in the Austro-Hungarian Empire is outlined, beginning with an initiative of the Austrian Academy of Sciences and the development of historical earthquake research as an independent research field after the 1978 "Zwentendorf plebiscite" on whether the nuclear power plant will start up. The applied methods are introduced briefly along with the most important studies and last but not least as an example of a recently carried out case study, one of the strongest past earthquakes in Austria, the earthquake of 17 July 1670, is presented. The research into historical earthquakes in Austria concentrates on seismic events of the pre-instrumental period. The investigations are not only of historical interest, but also contribute to the completeness and correctness of the Austrian earthquake catalogue, which is the basis for seismic hazard analysis and as such benefits the public, communities, civil engineers, architects, civil protection, and many others.

  6. Golden Gate Bridge response: a study with low-amplitude data from three earthquakes

    Science.gov (United States)

    Çelebi, Mehmet

    2012-01-01

    The dynamic response of the Golden Gate Bridge, located north of San Francisco, CA, has been studied previously using ambient vibration data and finite element models. Since permanent seismic instrumentation was installed in 1993, only small earthquakes that originated at distances varying between ~11 to 122 km have been recorded. Nonetheless, these records prompted this study of the response of the bridge to low amplitude shaking caused by three earthquakes. Compared to previous ambient vibration studies, the earthquake response data reveal a slightly higher fundamental frequency (shorter-period) for vertical vibration of the bridge deck center span (~7.7–8.3 s versus 8.2–10.6 s), and a much higher fundamental frequency (shorter period) for the transverse direction of the deck (~11.24–16.3 s versus ~18.2 s). In this study, it is also shown that these two periods are dominant apparent periods representing interaction between tower, cable, and deck.

  7. Urban design for post-earthquake reconstruction: A case study of Wenchuan County, China

    NARCIS (Netherlands)

    Liu, L.X.; Lin, Y.L.; Wang, S.F.

    2014-01-01

    Urban design for post-earthquake reconstruction emphasizes strategies, safety, memorials and institutional arrangements. It is closely related to earthquake recovery plans. This article reviews general studies on urban design for post-earthquake reconstruction, before focussing on the case of

  8. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2002-01-01

    SCK-CEN's R and D programme on instrumentation involves the development of advanced instrumentation systems for nuclear applications as well as the assessment of the performance of these instruments in a radiation environment. Particular emphasis is on the use of optical fibres as umbilincal links of a remote handling unit for use during maintanance of a fusion reacor, studies on the radiation hardening of plasma diagnostic systems; investigations on new instrumentation for the future MYRRHA accelerator driven system; space applications related to radiation-hardened lenses; the development of new approaches for dose, temperature and strain measurements; the assessment of radiation-hardened sensors and motors for remote handling tasks and studies of dose measurement systems including the use of optical fibres. Progress and achievements in these areas for 2001 are described

  9. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2002-04-01

    SCK-CEN's R and D programme on instrumentation involves the development of advanced instrumentation systems for nuclear applications as well as the assessment of the performance of these instruments in a radiation environment. Particular emphasis is on the use of optical fibres as umbilincal links of a remote handling unit for use during maintanance of a fusion reacor, studies on the radiation hardening of plasma diagnostic systems; investigations on new instrumentation for the future MYRRHA accelerator driven system; space applications related to radiation-hardened lenses; the development of new approaches for dose, temperature and strain measurements; the assessment of radiation-hardened sensors and motors for remote handling tasks and studies of dose measurement systems including the use of optical fibres. Progress and achievements in these areas for 2001 are described.

  10. A Study of the Historical Earthquake Catalog and Gutenberg-richter Parameter Values of the Korean Peninsula

    International Nuclear Information System (INIS)

    Seo, Jeong Moon; Choi, In Kil; Rhee, Hyun Me

    2010-01-01

    The KIER's Korean historical earthquake catalog was revised for MMI≥VI events recorded from the years 27 A.D. to 1904. The magnitude of each event was directly determined from the criteria suggested by Seo. The criteria incorporated the damage phenomena of the Japanese historical earthquake catalog, recent seismological studies, and the results of tests performed on ancient structures in Korea. Thus, the uncertainty of the magnitudes of the Korean historical earthquakes can be reduced. Also, the Gutenberg-Richter parameter values were estimated based on the revised catalog of this study. It was determined that the magnitudes of a maximum inland and minimum offshore event were approximately 6.3 and 6.5, respectively. The Gutenberg-Richter parameter pairs of the historical earthquake catalog were estimated to be a=5.32±0.21, b=0.95±0.19, which were somewhat lower than those obtained from recent complete instrumental earthquakes. No apparent change in the Gutenberg-Richter parameter is observed for the 16 th -17 th centuries of the seismically active period

  11. Experience with seismic instrumentation and real earthquake data at nuclear power plant Beznau Switzerland

    International Nuclear Information System (INIS)

    Sahgal, S.; Tinic, S.

    2005-01-01

    This paper deals with the aspects of design specification, bid evaluation and, seismic criteria used for the generation of seismic alarms etc. The paper also describes how the recorded data is utilized to check the various assumptions made in conjunction with the seismic plant design and seismic load generation. Out of some 8 seismic events registered so far only one event had the maximum recorded acceleration of approximately 28% of OBE Peak Ground Acceleration (PGA). From the real earthquakes experienced and the in-situ free-field ground accelerations recorded, the free-field response spectra were calculated. The calculated spectra are compared to the Regulatory Guide 1.60 Design Response Spectra scaled linearly to the site peak ground acceleration. The free field data recording units on the weathered rock and at the top of the soil provided a real data to calculate the site amplification factors. The in-situ amplification calculated is then compared to that used in the seismic design. The recorded acceleration time history at various plant grades were used to generate response spectra. The calculated response spectra were in turn compared to the spectra used in the seismic design. (authors)

  12. Earthquake source studies and seismic imaging in Alaska

    Science.gov (United States)

    Tape, C.; Silwal, V.

    2015-12-01

    Alaska is one of the world's most seismically and tectonically active regions. Its enhanced seismicity, including slab seismicity down to 180 km, provides opportunities (1) to characterize pervasive crustal faulting and slab deformation through the estimation of moment tensors and (2) to image subsurface structures to help understand the tectonic evolution of Alaska. Most previous studies of earthquakes and seismic imaging in Alaska have emphasized earthquake locations and body-wave travel-time tomography. In the past decade, catalogs of seismic moment tensors have been established, while seismic surface waves, active-source data, and potential field data have been used to improve models of seismic structure. We have developed moment tensor catalogs in the regions of two of the largest sedimentary basins in Alaska: Cook Inlet forearc basin, west of Anchorage, and Nenana basin, west of Fairbanks. Our moment tensor solutions near Nenana basin suggest a transtensional tectonic setting, with the basin developing in a stepover of a left-lateral strike-slip fault system. We explore the effects of seismic wave propagation from point-source and finite-source earthquake models by performing three-dimensional wavefield simulations using seismic velocity models that include major sedimentary basins. We will use our catalog of moment tensors within an adjoint-based, iterative inversion to improve the three-dimensional tomographic model of Alaska.

  13. Inter-Disciplinary Validation of Pre Earthquake Signals. Case Study for Major Earthquakes in Asia (2004-2010) and for 2011 Tohoku Earthquake

    Science.gov (United States)

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

    2012-01-01

    We carried out multi-sensors observations in our investigation of phenomena preceding major earthquakes. Our approach is based on a systematic analysis of several physical and environmental parameters, which we found, associated with the earthquake processes: thermal infrared radiation, temperature and concentration of electrons in the ionosphere, radon/ion activities, and air temperature/humidity in the atmosphere. We used satellite and ground observations and interpreted them with the Lithosphere-Atmosphere- Ionosphere Coupling (LAIC) model, one of possible paradigms we study and support. We made two independent continues hind-cast investigations in Taiwan and Japan for total of 102 earthquakes (M>6) occurring from 2004-2011. We analyzed: (1) ionospheric electromagnetic radiation, plasma and energetic electron measurements from DEMETER (2) emitted long-wavelength radiation (OLR) from NOAA/AVHRR and NASA/EOS; (3) radon/ion variations (in situ data); and 4) GPS Total Electron Content (TEC) measurements collected from space and ground based observations. This joint analysis of ground and satellite data has shown that one to six (or more) days prior to the largest earthquakes there were anomalies in all of the analyzed physical observations. For the latest March 11 , 2011 Tohoku earthquake, our analysis shows again the same relationship between several independent observations characterizing the lithosphere /atmosphere coupling. On March 7th we found a rapid increase of emitted infrared radiation observed from satellite data and subsequently an anomaly developed near the epicenter. The GPS/TEC data indicated an increase and variation in electron density reaching a maximum value on March 8. Beginning from this day we confirmed an abnormal TEC variation over the epicenter in the lower ionosphere. These findings revealed the existence of atmospheric and ionospheric phenomena occurring prior to the 2011 Tohoku earthquake, which indicated new evidence of a distinct

  14. Analog earthquakes

    International Nuclear Information System (INIS)

    Hofmann, R.B.

    1995-01-01

    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

  15. Groundwater electrical conductivity and soil radon gas monitoring for earthquake precursory studies in Koyna, India

    International Nuclear Information System (INIS)

    Reddy, D.V.; Nagabhushanam, P.

    2011-01-01

    Research highlights: → It is the first hydrochemical precursory study in the Koyna region, India. → Discrete conductivity measurements indicated progressive increase for 4 years. → Strong precursory EC change observed 40 h before the M 5.1 earthquake. → Precursory increase of soil Rn gas 20 days earlier than earthquakes M 4.7 and 5.1. → On-line monitoring of these parameters may help in earthquake forecast. - Abstract: Hourly monitoring of electrical conductivity (EC) of groundwater along with groundwater levels in the 210 m deep boreholes (specially drilled for pore pressure/earthquake studies) and soil Rn gas at 60 cm below ground level in real time, in the Koyna-Warna region (characterized by basaltic rocks, >1500 m thick, and dotted with several sets of fault systems), western India, provided strong precursory signatures in response to two earthquakes (M 4.7 on 14/11/09, and M 5.1 on 12/12/09) that occurred in the study region. The EC measured in Govare well water showed precursory perturbations about 40 h prior to the M 5.1 earthquake and continued further for about 20 h after the earthquake. In response to the M 4.7 earthquake, there were EC perturbations 8 days after the earthquake. In another well (Koyna) which is located 4 km north of Govare well, no precursory signatures were found for the M 4.7 earthquake, while for M 5.1 earthquake, post-seismic precursors were found 18 days after the earthquake. Increased porosity and reduced pressure head accompanied by mixing of a freshwater component from the top zone due to earthquakes are the suggested mechanisms responsible for the observed anomalies in EC. Another parameter, soil Rn gas showed relatively proportional strength signals corresponding to these two earthquakes. In both the cases, the pre-seismic increase in Rn concentration started about 20 days in advance. The co-seismic drop in Rn levels was less by 30% from its peak value for the M 4.7 earthquake and 50% for the M 5.1 earthquake. The Rn

  16. A longitudinal study of quality of life of earthquake survivors in L'Aquila, Italy.

    Science.gov (United States)

    Valenti, Marco; Masedu, Francesco; Mazza, Monica; Tiberti, Sergio; Di Giovanni, Chiara; Calvarese, Anna; Pirro, Roberta; Sconci, Vittorio

    2013-12-07

    People's well-being after loss resulting from an earthquake is a concern in countries prone to natural disasters. Most studies on post-earthquake subjective quality of life (QOL) have focused on the effects of psychological impairment and post-traumatic stress disorder (PTSD) on the psychological dimension of QOL. However, there is a need for studies focusing on QOL in populations not affected by PTSD or psychological impairment. The aim of this study was to estimate QOL changes over an 18-month period in an adult population sample after the L'Aquila 2009 earthquake. The study was designed as a longitudinal survey with four repeated measurements performed at six monthly intervals. The setting was the general population of an urban environment after a disruptive earthquake. Participants included 397 healthy adult subjects. Exclusion criteria were comorbidities such as physical, psychological, psychiatric or neurodegenerative diseases at the beginning of the study. The primary outcome measure was QOL, as assessed by the WHOQOL-BREF instrument. A generalised estimating equation model was run for each WHOQOL-BREF domain. Overall, QOL scores were observed to be significantly higher 18 months after the earthquake in all WHOQOL-BREF domains. The model detected an average increase in the physical QOL scores (from 66.6 ± 5.2 to 69.3 ± 4.7), indicating a better overall physical QOL for men. Psychological domain scores (from 64.9 ± 5.1 to 71.5 ± 6.5) were observed to be worse in men than in women. Levels at the WHOQOL domain for psychological health increased from the second assessment onwards in women, indicating higher resiliency. Men averaged higher scores than women in terms of social relationships and the environmental domain. Regarding the physical, psychological and social domains of QOL, scores in the elderly group (age > 60) were observed to be similar to each other regardless of the significant covariates used. WHOQOL-BREF scores of the psychological domain

  17. Statistical studies of vertical and horizontal earthquake spectra

    Energy Technology Data Exchange (ETDEWEB)

    Hall, W.J.; Mohraz, B.; Newmark, N.M.

    1976-01-01

    The study reveals that there is no well-defined dependence of normalized seismic design response spectra on the earthquake ground acceleration level. Recommendations for horizontal design response spectra are close to those given in Regulatory Guide 1.60. Recommendations for vertical response spectra are somewhat lower than Regulatory Guide 1.60 provisions in the frequency range 2 to 30 Hz aproximately. The results are based on seismic information recorded along the west coast of the United States and are directly applicable to that region only.

  18. Possibility to study ionospheric earthquakes precursors using CubeSats

    Science.gov (United States)

    Korepanov, Valery; Lappas, Vaios

    It is generally accepted that the earthquakes (EQ) are the most dangerous natural phenomena leading to the multiple losses in human lives and economics. The space observations must be included into the global chain of the EQ precursors monitoring at least as the initial warning to pay greater attention to the ground segment data. As the common opinion agrees, only in combination of multiple observation sites and set of monitored parameters the further progress at the way to raise EQ precursors detection probability may be obtained. There is necessary to answer two important questions before to plan any experiment to study ionospheric precursors of EQ. First one - whether the variations in the ionosphere definitely connected with the EQ preparation process do exist, and the second one - if they do, whether using these signals the precursors of EQ can be reliably identified and used for, if not prediction, then for the warning that the EQ in the given area approaches. The first successful mission dedicated to this problem solution was DEMETER (in orbit during more than 6 years from June 2004 until December 2010). The statistics of this study is impressive: altogether, about 9000 EQs with magnitude larger than M = 5.0 and depth lower than 40 km occurred all over the world during the analyzed period. In the result, the conclusion made there suggests that, obviously, there are real perturbations in the ionosphere connected with the seismic activity, but they are rather weak and at the present stage of data processing may be revealed only with the help of statistical analysis. To realize the study of ionospheric precursors, first it is imperative to clarify the mechanism of energy transfer along the chain “lithosphere-atmosphere-ionosphere”. Many hypotheses of such a mechanism exist, from which the mostly supported are fair weather currents (FWC) and atmospheric gravity waves (AGW), both of which have their pros and contras. The following minimal set of physical

  19. Risk assessment study of fire following earthquake: a case study of petrochemical enterprises in China

    Science.gov (United States)

    Li, J.; Wang, Y.; Chen, H.; Lin, L.

    2013-04-01

    After an earthquake, the fire risk of petrochemistry enterprises is higher than that of other enterprises as it involves production processes with inflammable and explosive characteristics. Using Chinese petrochemical enterprises as the research object, this paper uses a literature review and case summaries to study, amongst others, the classification of petrochemical enterprises, the proportion of daily fires, and fire loss ratio. This paper builds a fire following earthquake risk assessment model of petrochemical enterprises based on a previous earthquake fire hazard model, and the earthquake loss prediction assessment method, calculates the expected loss of the fire following earthquake in various counties and draws a risk map. Moreover, this research identifies high-risk areas, concentrating on the Beijing-Tianjin-Tangshan region, and Shandong, Jiangsu, and Zhejiang provinces. Differences in enterprise type produce different levels and distribution of petrochemical enterprises earthquake fire risk. Furthermore, areas at high risk of post-earthquake fires and with low levels of seismic fortification require extra attention to ensure appropriate mechanisms are in place.

  20. Risk assessment study of fire following an earthquake: a case study of petrochemical enterprises in China

    Science.gov (United States)

    Li, J.; Wang, Y.; Chen, H.; Lin, L.

    2014-04-01

    After an earthquake, the fire risk of petrochemical enterprises is higher than that of other enterprises as it involves production processes with inflammable and explosive characteristics. Using Chinese petrochemical enterprises as the research object, this paper uses a literature review and case summaries to study, amongst others, the classification of petrochemical enterprises, the proportion of daily fires, and fire loss ratio. This paper builds a fire following an earthquake risk assessment model of petrochemical enterprises based on a previous earthquake fire hazard model, and the earthquake loss prediction assessment method, calculates the expected loss of the fire following an earthquake in various counties and draws a risk map. Moreover, this research identifies high-risk areas, concentrating on the Beijing-Tianjin-Tangshan region, and Shandong, Jiangsu, and Zhejiang provinces. Differences in enterprise type produce different levels and distribution of petrochemical enterprise earthquake fire risk. Furthermore, areas at high risk of post-earthquake fires and with low levels of seismic fortification require extra attention to ensure appropriate mechanisms are in place.

  1. A forecast experiment of earthquake activity in Japan under Collaboratory for the Study of Earthquake Predictability (CSEP)

    Science.gov (United States)

    Hirata, N.; Yokoi, S.; Nanjo, K. Z.; Tsuruoka, H.

    2012-04-01

    One major focus of the current Japanese earthquake prediction research program (2009-2013), which is now integrated with the research program for prediction of volcanic eruptions, is to move toward creating testable earthquake forecast models. For this purpose we started an experiment of forecasting earthquake activity in Japan under the framework of the Collaboratory for the Study of Earthquake Predictability (CSEP) through an international collaboration. We established the CSEP Testing Centre, an infrastructure to encourage researchers to develop testable models for Japan, and to conduct verifiable prospective tests of their model performance. We started the 1st earthquake forecast testing experiment in Japan within the CSEP framework. We use the earthquake catalogue maintained and provided by the Japan Meteorological Agency (JMA). The experiment consists of 12 categories, with 4 testing classes with different time spans (1 day, 3 months, 1 year, and 3 years) and 3 testing regions called "All Japan," "Mainland," and "Kanto." A total of 105 models were submitted, and are currently under the CSEP official suite of tests for evaluating the performance of forecasts. The experiments were completed for 92 rounds for 1-day, 6 rounds for 3-month, and 3 rounds for 1-year classes. For 1-day testing class all models passed all the CSEP's evaluation tests at more than 90% rounds. The results of the 3-month testing class also gave us new knowledge concerning statistical forecasting models. All models showed a good performance for magnitude forecasting. On the other hand, observation is hardly consistent in space distribution with most models when many earthquakes occurred at a spot. Now we prepare the 3-D forecasting experiment with a depth range of 0 to 100 km in Kanto region. The testing center is improving an evaluation system for 1-day class experiment to finish forecasting and testing results within one day. The special issue of 1st part titled Earthquake Forecast

  2. Earthquake Archaeology: a case study from Ancient Cnidus

    Science.gov (United States)

    Stewart, I. S.; Altunel, E.; Piccardi, L.

    2003-04-01

    Ancient earthquakes can leave their mark in the mythical practices and literary accounts of ancient peoples, the stratigraphy of their site histories, and the structural integrity of their constructions. The ancient Greek/Roman city of Cnidus in southwestern Turkey records all three. A spectacular exposed fault plane cliff bordering the northern edge of the city appears to have been an important revered site, bearing votive niches carved into the near-vertical slip plane and associated with a Sanctuary of Demeter that implies a connection to the underworld. Stratigraphic evidence for earthquake faulting can be found in the form of a destruction horizon of contorted soil, relics and human remains exposed in the original excavations of the Sanctuary of Demeter by Sir Charles Newton (1857-58) and in a destruction horizon of burnt soil and bone uncovered by the ongoing excavation of a colonnaded street. Structural damage to constructions is widespread across the site, with warped and offset walls in the Sanctuary of Demeter, collapsed buildings in several places, and a parallel arrangement of fallen columns in the colonnaded street. The most remarkable structural evidence for fault activity, however, is the rupture of the ancient city's famous Round Temple of Aphrodite, whose podium reveals a history of damage and which is unambiguously displaced across a bedrock fault. While these phenomena are equivocal when viewed in isolation, collectively they imply at least two damaging earthquakes at the site, one (possibly both) of which ruptured along the fault on which the city is found. The Cnidus case study highlights how reliable identification of archaeoseismic damage relies on compiling an assemblage of indicators rather than the discovery of a diagnostic "smoking gun".

  3. Feasibility study of EEW application in Korea ; Testing different frequency bands for small earthquakes.

    Science.gov (United States)

    Chi, H. C.; Park, J. H.; Sheen, D. H.

    2009-04-01

    At present, it seems almost impossible to predict where and how much strong a earthquake will happen within very limited time such as two or three days before it occurs. However, the advantage of modern electronic techniques can support us very fast communication tools around nation-wide area so that we can receive P- waves arrival information from seismic stations through communication lines before S-waves strike our living site. This is the key of EEW(Earthquake Early Warning) concept that is under development around world especially including Japan, United State of America, and Taiwan. In this pilot study we proposed the direction for developing Korean Earthquake Early Warning System. Considering the state of the art techniques used in Japan, USA and Taiwan, ElarmS would be more adaptable to Korea since ElarmS can work from the low limit of moderate earthquakes around magnitude 3.5, which would annually happen in Korea. Using 27 events ranging in magnitude from 2.2 to 4.9 occurring in South Korea for 2007, we investigate empirical magnitude scaling relationships in South Korea due to the variation of the duration of the P waveform. We measure the maximum predominant period and the peak displacement or velocity amplitude from the first few seconds of P wave arrivals to derive period-magnitude and amplitude-magnitude scaling relationship, respectively. We find that it is possible to determine the magnitude of earthquakes only using the first 2 seconds of the P wave and, for the period-magnitude relationship, 10 Hz low-pass filter yields better estimate than 3 Hz. This is because the magnitudes of most events used in this study are too small (<3.0). It is also shown that peak displacement for velocity instruments and peak velocity for accelerometers have their own magnitude scaling relationships, respectively. Thus, for the amplitude-magnitude relationship, like the relationships in northern California, two individual amplitude scaling relationships would be

  4. Source study of the Jan Mayen transform fault strike-slip earthquakes

    Science.gov (United States)

    Rodríguez-Pérez, Q.; Ottemöller, L.

    2014-07-01

    Seismic source parameters of oceanic transform zone earthquakes have been relatively poorly studied. Previous studies showed that this type of earthquakes has unique characteristics such as not only the relatively common occurrence of slow events with weak seismic radiation at high frequencies but also the occurrence of some events that have high apparent stress indicating strong high frequency radiation. We studied 5 strike-slip earthquakes in the Jan Mayen fracture zone with magnitudes in the range of 5.9 centroid time delay compared to other oceanic transform fault earthquakes.

  5. Swedish earthquakes and acceleration probabilities

    International Nuclear Information System (INIS)

    Slunga, R.

    1979-03-01

    A method to assign probabilities to ground accelerations for Swedish sites is described. As hardly any nearfield instrumental data is available we are left with the problem of interpreting macroseismic data in terms of acceleration. By theoretical wave propagation computations the relation between seismic strength of the earthquake, focal depth, distance and ground accelerations are calculated. We found that most Swedish earthquake of the area, the 1904 earthquake 100 km south of Oslo, is an exception and probably had a focal depth exceeding 25 km. For the nuclear power plant sites an annual probability of 10 -5 has been proposed as interesting. This probability gives ground accelerations in the range 5-20 % for the sites. This acceleration is for a free bedrock site. For consistency all acceleration results in this study are given for bedrock sites. When applicating our model to the 1904 earthquake and assuming the focal zone to be in the lower crust we get the epicentral acceleration of this earthquake to be 5-15 % g. The results above are based on an analyses of macrosismic data as relevant instrumental data is lacking. However, the macroseismic acceleration model deduced in this study gives epicentral ground acceleration of small Swedish earthquakes in agreement with existent distant instrumental data. (author)

  6. The study of earthquakes in the hundred years following the Lisbon earthquake of 1755

    Czech Academy of Sciences Publication Activity Database

    Oldroyd, D. R.; Amador, F.; Kozák, Jan; Carneiro, A.; Pinto, M.

    2007-01-01

    Roč. 26, č. 2 (2007), s. 321-370 ISSN 0736-623X Institutional research plan: CEZ:AV0Z30120515 Keywords : 1755 Lisbon earthquake * post-Lisbon seismology * seismic waves Subject RIV: DC - Siesmology, Volcanology, Earth Structure

  7. Calibration and validation of earthquake catastrophe models. Case study: Impact Forecasting Earthquake Model for Algeria

    Science.gov (United States)

    Trendafiloski, G.; Gaspa Rebull, O.; Ewing, C.; Podlaha, A.; Magee, B.

    2012-04-01

    Calibration and validation are crucial steps in the production of the catastrophe models for the insurance industry in order to assure the model's reliability and to quantify its uncertainty. Calibration is needed in all components of model development including hazard and vulnerability. Validation is required to ensure that the losses calculated by the model match those observed in past events and which could happen in future. Impact Forecasting, the catastrophe modelling development centre of excellence within Aon Benfield, has recently launched its earthquake model for Algeria as a part of the earthquake model for the Maghreb region. The earthquake model went through a detailed calibration process including: (1) the seismic intensity attenuation model by use of macroseismic observations and maps from past earthquakes in Algeria; (2) calculation of the country-specific vulnerability modifiers by use of past damage observations in the country. The use of Benouar, 1994 ground motion prediction relationship was proven as the most appropriate for our model. Calculation of the regional vulnerability modifiers for the country led to 10% to 40% larger vulnerability indexes for different building types compared to average European indexes. The country specific damage models also included aggregate damage models for residential, commercial and industrial properties considering the description of the buildings stock given by World Housing Encyclopaedia and the local rebuilding cost factors equal to 10% for damage grade 1, 20% for damage grade 2, 35% for damage grade 3, 75% for damage grade 4 and 100% for damage grade 5. The damage grades comply with the European Macroseismic Scale (EMS-1998). The model was validated by use of "as-if" historical scenario simulations of three past earthquake events in Algeria M6.8 2003 Boumerdes, M7.3 1980 El-Asnam and M7.3 1856 Djidjelli earthquake. The calculated return periods of the losses for client market portfolio align with the

  8. Feasibility study of short-term earthquake prediction using ionospheric anomalies immediately before large earthquakes

    Science.gov (United States)

    Heki, K.; He, L.

    2017-12-01

    We showed that positive and negative electron density anomalies emerge above the fault immediately before they rupture, 40/20/10 minutes before Mw9/8/7 earthquakes (Heki, 2011 GRL; Heki and Enomoto, 2013 JGR; He and Heki 2017 JGR). These signals are stronger for earthquake with larger Mw and under higher background vertical TEC (total electron conetent) (Heki and Enomoto, 2015 JGR). The epicenter, the positive and the negative anomalies align along the local geomagnetic field (He and Heki, 2016 GRL), suggesting electric fields within ionosphere are responsible for making the anomalies (Kuo et al., 2014 JGR; Kelley et al., 2017 JGR). Here we suppose the next Nankai Trough earthquake that may occur within a few tens of years in Southwest Japan, and will discuss if we can recognize its preseismic signatures in TEC by real-time observations with GNSS.During high geomagnetic activities, large-scale traveling ionospheric disturbances (LSTID) often propagate from auroral ovals toward mid-latitude regions, and leave similar signatures to preseismic anomalies. This is a main obstacle to use preseismic TEC changes for practical short-term earthquake prediction. In this presentation, we show that the same anomalies appeared 40 minutes before the mainshock above northern Australia, the geomagnetically conjugate point of the 2011 Tohoku-oki earthquake epicenter. This not only demonstrates that electric fields play a role in making the preseismic TEC anomalies, but also offers a possibility to discriminate preseismic anomalies from those caused by LSTID. By monitoring TEC in the conjugate areas in the two hemisphere, we can recognize anomalies with simultaneous onset as those caused by within-ionosphere electric fields (e.g. preseismic anomalies, night-time MSTID) and anomalies without simultaneous onset as gravity-wave origin disturbances (e.g. LSTID, daytime MSTID).

  9. Instrumentation for millisecond-resolution scattering studies

    International Nuclear Information System (INIS)

    Stephenson, G.B.; Ludwig, K.F. Jr.; Jordan-Sweet, J.L.; Brauer, S.; Mainville, J.; Yang, Y.S.; Sutton, M.

    1989-01-01

    Time-resolved x-ray scattering studies of phase transition kinetics have been carried out using the wide-bandpass monochromator and fast linear position-sensitive detector system at the IBM/MIT beamline X-20C at the National Synchrotron Light Source (NSLS). We report here on the instrumentation that has been developed for these studies, and in particular on the methods used to measure, change, and control sample temperature with millisecond resolution

  10. Study of the structure changes caused by earthquakes in Chile applying the lineament analysis to the Aster (Terra) satellite data.

    Science.gov (United States)

    Arellano-Baeza, A.; Zverev, A.; Malinnikov, V.

    Chile is one of the most seismically and volcanically active regions in the South America due to a constant subdiction of the South American plate, converging with the Nazca plate in the extreme North of Chile. Four events, namely: the Ovalle earthquake of Juny 18, 2003, M=6.3, with epicenter localized at (-30:49:33, -71:18:53), the Calama earthquake of Junly 19, 2001, M=5.2, (-30:29:38,-68:33:18), the Pica earthquake of April 10, 2003, M=5.1, (-21:03:20,-68:47:10) and the La Ligua earthquake of May 6, 2001, M=5.1, (-32:35:31,-71:07:58:) were analysed using the 15 m resolution satellite images, provided by the ASTER/VNIR instrument. The Lineament Extraction and Stripes Statistic Analysis (LESSA) software package was used to examine changes in the lineament features caused by sismic activity. Lack of vegetation facilitates the study of the changes in the topography common to all events and makes it possible to evaluate the sismic risk in this region for the future.

  11. Study on earthquake responses of overhead traveling cranes

    International Nuclear Information System (INIS)

    Komori, A.; Fukuda, T.; Veki, T.; Kirata, M.; Hoshii, T.; Kashiwazaki, A.

    1989-01-01

    In nuclear power plants, large-size overhead traveling cranes, such as reactor building crane and turbine building crane, are installed. These overhead cranes are used for transporting heavy loads on the operation floor, and call for safety and reliability even during strong earthquake as well as under the normal operational conditions. The seismic behaviors of overhead traveling cranes, which move on the rails, may be different from those of other structures that are anchored to the building: in the case of cranes, traveling wheels and rails can slip relative to each other when the horizontal seismic force reaches the level of frictional force. In Japan, therefore, a practical guide to the seismic design that considers the sliding has been proposed. However, detailed experimental study on sliding between wheels and rails has not been carried out. In this study, the seismic behaviors of traveling overhead cranes accompanied by sliding between wheels and rails in the traveling direction are examined

  12. Analysis of soil radon data in earthquake precursory studies

    Directory of Open Access Journals (Sweden)

    Hari Prasad Jaishi

    2014-10-01

    Full Text Available Soil radon data were recorded at two selected sites along Mat fault in Mizoram (India, which lies in the highest seismic zone in India. The study was carried out during July 2011 to May 2013 using LR-115 Type II films. Precursory changes in radon concentration were observed prior to some earthquakes that occurred around the measuring sites. Positive correlation was found between the measured radon data and the seismic activity in the region. Statistical analysis of the radon data together with the meteorological parameters was done using Multiple Regression Method. Results obtained show that the method employed was useful for removing the effect of meteorological parameters and to identify radon maxima possibly caused by seismic activity.

  13. Instrumented Moles for Planetary Subsurface Regolith Studies

    Science.gov (United States)

    Richter, L. O.; Coste, P. A.; Grzesik, A.; Knollenberg, J.; Magnani, P.; Nadalini, R.; Re, E.; Romstedt, J.; Sohl, F.; Spohn, T.

    2006-12-01

    Soil-like materials, or regolith, on solar system objects provide a record of physical and/or chemical weathering processes on the object in question and as such possess significant scientific relevance for study by landed planetary missions. In the case of Mars, a complex interplay has been at work between impact gardening, aeolian as well as possibly fluvial processes. This resulted in regolith that is texturally as well as compositionally layered as hinted at by results from the Mars Exploration Rover (MER) missions which are capable of accessing shallow subsurface soils by wheel trenching. Significant subsurface soil access on Mars, i.e. to depths of a meter or more, remains to be accomplished on future missions. This has been one of the objectives of the unsuccessful Beagle 2 landed element of the ESA Mars Express mission having been equipped with the Planetary Underground Tool (PLUTO) subsurface soil sampling Mole system capable of self-penetration into regolith due to an internal electro-mechanical hammering mechanism. This lightweight device of less than 900 g mass was designed to repeatedly obtain and deliver to the lander regolith samples from depths down to 2 m which would have been analysed for organic matter and, specifically, organic carbon from potential extinct microbial activity. With funding from the ESA technology programme, an evolved Mole system - the Instrumented Mole System (IMS) - has now been developed to a readiness level of TRL 6. The IMS is to serve as a carrier for in situ instruments for measurements in planetary subsurface soils. This could complement or even eliminate the need to recover samples to the surface. The Engineering Model hardware having been developed within this effort is designed for accommodating a geophysical instrument package (Heat Flow and Physical Properties Package, HP3) that would be capable of measuring regolith physical properties and planetary heat flow. The chosen design encompasses a two-body Mole

  14. OMG Earthquake! Can Twitter improve earthquake response?

    Science.gov (United States)

    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

  15. Study on China’s Earthquake Prediction by Mathematical Analysis and its Application in Catastrophe Insurance

    Science.gov (United States)

    Jianjun, X.; Bingjie, Y.; Rongji, W.

    2018-03-01

    The purpose of this paper was to improve catastrophe insurance level. Firstly, earthquake predictions were carried out using mathematical analysis method. Secondly, the foreign catastrophe insurances’ policies and models were compared. Thirdly, the suggestions on catastrophe insurances to China were discussed. The further study should be paid more attention on the earthquake prediction by introducing big data.

  16. Instrument for Study of Microbial Thermal Inactivation

    Science.gov (United States)

    Dickerson, R. W.; Read, R. B.

    1968-01-01

    An instrument was designed for the study of thermal inactivation of microorganisms using heating times of less than 1 sec. The instrument operates on the principle of rapid automatic displacement of the microorganism to and from a saturated steam atmosphere, and the operating temperature range is 50 to 90 C. At a temperature of 70 C, thermometric lag (time required to respond to 63.2% of a step change) of the fluid sample containing microorganisms was 0.12 sec. Heating time required to heat the sample to within 0.1 C of the exposure temperature was less than 1 sec, permitting exposure periods as brief as 1 sec, provided the proper corrections are made for the lethal effect of heating. The instrument is most useful for heat exposure periods of less than 5 min, and, typically, more than 500 samples can be processed for microbial inactivation determinations within an 8-hr period. Images Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 7 Fig. 8 PMID:4874466

  17. Composite Earthquake Catalog of the Yellow Sea for Seismic Hazard Studies

    Science.gov (United States)

    Kang, S. Y.; Kim, K. H.; LI, Z.; Hao, T.

    2017-12-01

    The Yellow Sea (a.k.a West Sea in Korea) is an epicontinental and semi-closed sea located between Korea and China. Recent earthquakes in the Yellow Sea including, but not limited to, the Seogyuckryulbi-do (1 April 2014, magnitude 5.1), Heuksan-do (21 April 2013, magnitude 4.9), Baekryung-do (18 May 2013, magnitude 4.9) earthquakes, and the earthquake swarm in the Boryung offshore region in 2013, remind us of the seismic hazards affecting east Asia. This series of earthquakes in the Yellow Sea raised numerous questions. Unfortunately, both governments have trouble in monitoring seismicity in the Yellow Sea because earthquakes occur beyond their seismic networks. For example, the epicenters of the magnitude 5.1 earthquake in the Seogyuckryulbi-do region in 2014 reported by the Korea Meteorological Administration and China Earthquake Administration differed by approximately 20 km. This illustrates the difficulty with seismic monitoring and locating earthquakes in the region, despite the huge effort made by both governments. Joint effort is required not only to overcome the limits posed by political boundaries and geographical location but also to study seismicity and the underground structures responsible. Although the well-established and developing seismic networks in Korea and China have provided unprecedented amount and quality of seismic data, high quality catalog is limited to the recent 10s of years, which is far from major earthquake cycle. It is also noticed the earthquake catalog from either country is biased to its own and cannot provide complete picture of seismicity in the Yellow Sea. In order to understand seismic hazard and tectonics in the Yellow Sea, a composite earthquake catalog has been developed. We gathered earthquake information during last 5,000 years from various sources. There are good reasons to believe that some listings account for same earthquake, but in different source parameters. We established criteria in order to provide consistent

  18. Initial Earthquake Centrifuge Model Experiments for the Study of Liquefaction

    National Research Council Canada - National Science Library

    Steedman, R

    1998-01-01

    .... These are intended to gather data suitable for the development of improved design approaches for the prediction of liquefaction under earthquake loading using the new centrifuge facility at the WES...

  19. Digital study of nuclear reactor instrument

    International Nuclear Information System (INIS)

    Lv Gongxiang; Yang Zhijun

    2006-01-01

    The paper introduces the design method of nuclear reactor's digital instrument developed by authors based on the AT89C52 single chip microcomputer. Also the instrument system hardware structure and software framework are given. The instrument apply DDC112 which is responsible for the measure of lower current. When designing the instrument system, anti-interference measure of software, especially hardware is considered seriously. (authors)

  20. Preliminary Study on Earthquake Surface Rupture Extraction from Uav Images

    Science.gov (United States)

    Yuan, X.; Wang, X.; Ding, X.; Wu, X.; Dou, A.; Wang, S.

    2018-04-01

    Because of the advantages of low-cost, lightweight and photography under the cloud, UAVs have been widely used in the field of seismic geomorphology research in recent years. Earthquake surface rupture is a typical seismic tectonic geomorphology that reflects the dynamic and kinematic characteristics of crustal movement. The quick identification of earthquake surface rupture is of great significance for understanding the mechanism of earthquake occurrence, disasters distribution and scale. Using integrated differential UAV platform, series images were acquired with accuracy POS around the former urban area (Qushan town) of Beichuan County as the area stricken seriously by the 2008 Wenchuan Ms8.0 earthquake. Based on the multi-view 3D reconstruction technique, the high resolution DSM and DOM are obtained from differential UAV images. Through the shade-relief map and aspect map derived from DSM, the earthquake surface rupture is extracted and analyzed. The results show that the surface rupture can still be identified by using the UAV images although the time of earthquake elapse is longer, whose middle segment is characterized by vertical movement caused by compression deformation from fault planes.

  1. Instrumentation

    International Nuclear Information System (INIS)

    Prieur, G.; Nadi, M.; Hedjiedj, A.; Weber, S.

    1995-01-01

    This second chapter on instrumentation gives little general consideration on history and classification of instrumentation, and two specific states of the art. The first one concerns NMR (block diagram of instrumentation chain with details on the magnets, gradients, probes, reception unit). The first one concerns precision instrumentation (optical fiber gyro-meter and scanning electron microscope), and its data processing tools (programmability, VXI standard and its history). The chapter ends with future trends on smart sensors and Field Emission Displays. (D.L.). Refs., figs

  2. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2000-01-01

    SCK-CEN's research and development programme on instrumentation aims at evaluating the potentials of new instrumentation technologies under the severe constraints of a nuclear application. It focuses on the tolerance of sensors to high radiation doses, including optical fibre sensors, and on the related intelligent data processing needed to cope with the nuclear constraints. Main achievements in these domains in 1999 are summarised

  3. People's perspectives and expectations on preparedness against earthquakes: Tehran case study.

    Science.gov (United States)

    Jahangiri, Katayoun; Izadkhah, Yasamin Ostovar; Montazeri, Ali; Hosseinip, Mahmood

    2010-06-01

    Public education is one of the most important elements of earthquake preparedness. The present study identifies methods and appropriate strategies for public awareness and education on preparedness for earthquakes based on people's opinions in the city of Tehran. This was a cross-sectional study and a door-to-door survey of residents from 22 municipal districts in Tehran, the capital city of Iran. It involved a total of 1 211 individuals aged 15 and above. People were asked about different methods of public information and education, as well as the type of information needed for earthquake preparedness. "Enforcing the building contractors' compliance with the construction codes and regulations" was ranked as the first priority by 33.4% of the respondents. Over 70% of the participants (71.7%) regarded TV as the most appropriate means of media communication to prepare people for an earthquake. This was followed by "radio" which was selected by 51.6% of respondents. Slightly over 95% of the respondents believed that there would soon be an earthquake in the country, and 80% reported that they obtained this information from "the general public". Seventy percent of the study population felt that news of an earthquake should be communicated through the media. However, over fifty (58%) of the participants believed that governmental officials and agencies are best qualified to disseminate information about the risk of an imminent earthquake. Just over half (50.8%) of the respondents argued that the authorities do not usually provide enough information to people about earthquakes and the probability of their occurrence. Besides seismologists, respondents thought astronauts (32%), fortunetellers (32.3%), religious figures (34%), meteorologists (23%), and paleontologists (2%) can correctly predict the occurrence of an earthquake. Furthermore, 88.6% listed aid centers, mosques, newspapers and TV as the most important sources of information during the aftermath of an earthquake

  4. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2001-04-01

    SCK-CEN's research and development programme on instrumentation involves the assessment and the development of sensitive measurement systems used within a radiation environment. Particular emphasis is on the assessment of optical fibre components and their adaptability to radiation environments. The evaluation of ageing processes of instrumentation in fission plants, the development of specific data evaluation strategies to compensate for ageing induced degradation of sensors and cable performance form part of these activities. In 2000, particular emphasis was on in-core reactor instrumentation applied to fusion, accelerator driven and water-cooled fission reactors. This involved the development of high performance instrumentation for irradiation experiments in the BR2 reactor in support of new instrumentation needs for MYRRHA, and for diagnostic systems for the ITER reactor.

  5. Instrumentation

    International Nuclear Information System (INIS)

    Decreton, M.

    2001-01-01

    SCK-CEN's research and development programme on instrumentation involves the assessment and the development of sensitive measurement systems used within a radiation environment. Particular emphasis is on the assessment of optical fibre components and their adaptability to radiation environments. The evaluation of ageing processes of instrumentation in fission plants, the development of specific data evaluation strategies to compensate for ageing induced degradation of sensors and cable performance form part of these activities. In 2000, particular emphasis was on in-core reactor instrumentation applied to fusion, accelerator driven and water-cooled fission reactors. This involved the development of high performance instrumentation for irradiation experiments in the BR2 reactor in support of new instrumentation needs for MYRRHA, and for diagnostic systems for the ITER reactor

  6. A contrast study of the traumatic condition between the wounded in 5.12 Wenchuan earthquake and 4.25 Nepal earthquake.

    Science.gov (United States)

    Ding, Sheng; Hu, Yonghe; Zhang, Zhongkui; Wang, Ting

    2015-01-01

    5.12 Wenchuan earthquake and 4.25 Nepal earthquake are of the similar magnitude, but the climate and geographic environment are totally different. Our team carried out medical rescue in both disasters, so we would like to compare the different traumatic conditions of the wounded in two earthquakes. The clinical data of the wounded respectively in 5.12 Wenchuan earthquake and 4.25 Nepal earthquake rescued by Chengdu Military General Hospital were retrospectively analyzed. Then a contrast study between the wounded was conducted in terms of age, sex, injury mechanisms, traumatic conditions, complications and prognosis. Three days after 5.12 Wenchuan earthquake, 465 cases of the wounded were hospitalized in Chengdu Military General Hospital, including 245 males (52.7%) and 220 females (47.3%) with the average age of (47.6±22.7) years. Our team carried out humanitarian relief in Katmandu after 4.25 Nepal earthquake. Three days after this disaster, 71 cases were treated in our field hospital, including 37 males (52.1%) and 34 females (47.9%) with the mean age of (44.8±22.9) years. There was no obvious difference in sex and mean age between two groups, but the age distribution was a little different: there were more wounded people at the age over 60 years in 4.25 Nepal earthquake (pearthquake (pearthquake had a higher rate of bruise injury and crush injury (pearthquake had a higher rate of falling injury (pearthquake, 4.25 Nepal earthquake has a much higher incidence of limb fractures (pearthquakes of the similar magnitude can cause different injury mechanisms, traumatic conditions and complications in the wounded under different climate and geographic environment.When an earthquake occurs in a poor traffic area of high altitude and large temperature difference, early medical rescue, injury control and wounded evacuation as well as sufficient warmth retention and food supply are of vital significance.

  7. Virtual instrumentation: a new approach for control and instrumentation - application in containment studies facility

    International Nuclear Information System (INIS)

    Gole, N.V.; Shanware, V.M.; Sebastian, A.; Subramaniam, K.

    2001-01-01

    PC based data-acquisition has emerged as a rapidly developing area particularly with respect to process instrumentation. Computer based data acquisition in process instrumentation combined with Supervisory Control and Data Acquisition (SCADA) software has introduced extensive possibilities with respect to formats for presentation of information. The concept of presenting data using any instrument format with the help of software tools to simulate the instrument on screen, needs to be understood, in order to be able to make use of its vast potential. The purpose of this paper is to present the significant features of the Virtual Instrumentation concept and discuss its application in the instrumentation and control system of containment studies facility (CSF). Factors involved in the development of the virtual instrumentation based I and C system for CSF are detailed and a functional overview of the system configuration is given. (author)

  8. Natural course of posttraumatic stress disorder: a 20-month prospective study of Turkish earthquake survivors.

    Science.gov (United States)

    Karamustafalioglu, Oguz K; Zohar, Joseph; Güveli, Mustafa; Gal, Gilad; Bakim, Bahadir; Fostick, Leah; Karamustafalioglu, Nesrin; Sasson, Yehuda

    2006-06-01

    A 20-month prospective follow-up of survivors of the severe earthquake in Turkey in 1999 examined the natural course of posttraumatic stress disorder (PTSD) and the contribution of different symptom clusters to the emergence of PTSD. Subjects were randomly sampled in a suburb of Istanbul that was severely affected by the earthquake. A total of 464 adults were assessed with a self-report instrument for PTSD symptoms on 3 consecutive surveys that were administered 1 to 3, 6 to 10, and 18 to 20 months following the earthquake. The prevalence of PTSD was 30.2% on the first survey and decreased to 26.9% and 10.6% on the second and third surveys, respectively. Female subjects showed initially higher (34.8%) PTSD rates compared with male subjects (19.1%). However, gender differences disappeared by the time of the third survey due to high spontaneous remission rates in female subjects. Low levels of chronic and delayed-onset PTSD were observed. A major contribution of the avoidance symptoms to PTSD diagnosis was identified by statistical analysis. Initial PTSD following an earthquake may be as prevalent as in other natural disasters, but high rates of spontaneous remission lead to low prevalence 1.5 years following the earthquake. Initial avoidance characteristics play a major role in the emergence of PTSD.

  9. Crowdsourced earthquake early warning

    Science.gov (United States)

    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.

  10. Instrumentation

    Energy Technology Data Exchange (ETDEWEB)

    Decreton, M

    2000-07-01

    SCK-CEN's research and development programme on instrumentation aims at evaluating the potentials of new instrumentation technologies under the severe constraints of a nuclear application. It focuses on the tolerance of sensors to high radiation doses, including optical fibre sensors, and on the related intelligent data processing needed to cope with the nuclear constraints. Main achievements in these domains in 1999 are summarised.

  11. Class Room Exercises Using JMA-59-Type Seismograms for Earthquake Study at High-School Level

    Science.gov (United States)

    Okamoto, Y.; Furuta, S.; Hirota, N.

    2013-12-01

    The JMA-59-type electromagnetic seismograph was the standard seismograph for routine observations by the Japan Meteorological Agency (JMA) from the 1960's to the 1990's. Some features of those seismograms include 1) displacement wave records (electrically integrated from a velocity output by a moving-coil-type sensor), 2) ink records on paper (analog recording with time marks), 3) continuous drum recording for 12 h, and 4) lengthy operation time over several decades. However, the digital revolution in recording systems during the 1990's made these analog features obsolete, and their abundant and bulky paper-based records were stacked and sometimes disregarded in the library of every observatory. Interestingly, from an educational aspect, the disadvantages of these old-fashioned systems become highly advantageous for educational or outreach purposes. The updated digital instrument is essentially a 'black-box,' not revealing its internal mechanisms and being too fast for observing its signal processes. While the old seismometers and recording systems have been disposed of long since, stacks of analog seismograms continue to languish in observatories' back rooms. In our study, we develop some classroom exercises for studying earthquakes at the mid- to high-school level using these analog seismograms. These exercises include 1) reading the features of seismic records, 2) measuring the S-P time, 3) converting the hypocentral distance from Omori's distance formula, 4) locating the epicenter/hypocenter using the S-P times of surrounding stations, and 5) estimating earthquake magnitude using the Tsuboi's magnitude formula. For this calculation we developed a 'nomogram'--a graphical paper calculator created using a Python-based freeware tool named 'PyNomo.' We tested many seismograms and established the following rules: 1) shallow earthquakes are appropriate for using the Tsuboi's magnitude formula; 2) there is no saturation at peak amplitude; 3) seismograms make it easy to

  12. Attention bias in earthquake-exposed survivors: an event-related potential study.

    Science.gov (United States)

    Zhang, Yan; Kong, Fanchang; Han, Li; Najam Ul Hasan, Abbasi; Chen, Hong

    2014-12-01

    The Chinese Wenchuan earthquake, which happened on the 28th of May in 2008, may leave deep invisible scars in individuals. China has a large number of children and adolescents, who tend to be most vulnerable because they are in an early stage of human development and possible post-traumatic psychological distress may have a life-long consequence. Trauma survivors without post-traumatic stress disorder (PTSD) have received little attention in previous studies, especially in event-related potential (ERP) studies. We compared the attention bias to threat stimuli between the earthquake-exposed group and the control group in a masked version of the dot probe task. The target probe presented at the same space location consistent with earthquake-related words was the congruent trial, while in the space location of neutral words was the incongruent trial. Thirteen earthquake-exposed middle school students without PTSD and 13 matched controls were included in this investigation. The earthquake-exposed group showed significantly faster RTs to congruent trials than to incongruent trials. The earthquake-exposed group produced significantly shorter C1 and P1 latencies and larger C1, P1 and P2 amplitudes than the control group. In particular, enhanced P1 amplitude to threat stimuli was observed in the earthquake-exposed group. These findings are in agreement with the prediction that earthquake-exposed survivors have an attention bias to threat stimuli. The traumatic event had a much greater effect on earthquake-exposed survivors even if they showed no PTSD symptoms than individuals in the controls. These results will provide neurobiological evidences for effective intervention and prevention to post-traumatic mental problems. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Teaching case studies on earthquake preparedness efforts in the transportation sector, Los Angeles metropolitan area.

    Science.gov (United States)

    2013-01-01

    Through the development of a Harvard Kennedy School case study (intended for : use as curriculum in graduate-level and executive education programs), this project : examines earthquake preparedness and planning processes in the Los Angeles : metropol...

  14. Instrumentation

    International Nuclear Information System (INIS)

    Umminger, K.

    2008-01-01

    A proper measurement of the relevant single and two-phase flow parameters is the basis for the understanding of many complex thermal-hydraulic processes. Reliable instrumentation is therefore necessary for the interaction between analysis and experiment especially in the field of nuclear safety research where postulated accident scenarios have to be simulated in experimental facilities and predicted by complex computer code systems. The so-called conventional instrumentation for the measurement of e. g. pressures, temperatures, pressure differences and single phase flow velocities is still a solid basis for the investigation and interpretation of many phenomena and especially for the understanding of the overall system behavior. Measurement data from such instrumentation still serves in many cases as a database for thermal-hydraulic system codes. However some special instrumentation such as online concentration measurement for boric acid in the water phase or for non-condensibles in steam atmosphere as well as flow visualization techniques were further developed and successfully applied during the recent years. Concerning the modeling needs for advanced thermal-hydraulic codes, significant advances have been accomplished in the last few years in the local instrumentation technology for two-phase flow by the application of new sensor techniques, optical or beam methods and electronic technology. This paper will give insight into the current state of instrumentation technology for safety-related thermohydraulic experiments. Advantages and limitations of some measurement processes and systems will be indicated as well as trends and possibilities for further development. Aspects of instrumentation in operating reactors will also be mentioned.

  15. Study of responses of 64-story Rincon Building to Napa, Fremont, Piedmont, San Ramon earthquakes and ambient motions

    Science.gov (United States)

    Çelebi, Mehmet; Hooper, John; Klemencic, Ron

    2017-01-01

    We analyze the recorded responses of a 64-story, instrumented, concrete core shear wall building in San Francisco, California, equipped with tuned sloshing liquid dampers (TSDs) and buckling restraining braces (BRBs). Previously, only ambient data from the 72-channel array in the building were studied (Çelebi et al. 2013). Recently, the 24 August 2014 Mw 6.0 Napa and three other earthquakes were recorded. The peak accelerations of ambient and the larger Napa earthquake responses at the basement are 0.12 cm/s/s and 5.2 cm/s/s respectively—a factor of ~42. At the 61st level, they are 0.30 cm/s/s (ambient) and 16.8 cm/s/s (Napa), respectively—a factor of ~56. Fundamental frequencies (NS ~ 0.3, EW ~ 0.27 Hz) from earthquake responses vary within an insignificant frequency band of ~0.02–0.03 Hz when compared to those from ambient data. In the absence of soil-structure interaction (SSI), these small and insignificant differences may be attributed to (1) identification errors, (2) any nonlinear behavior, and (3) shaking levels that are not large enough to activate the BRBs and TSDs to make significant shifts in frequencies and increase damping.

  16. The installation and operation of the seismic instrumentation in Korean NPPs

    International Nuclear Information System (INIS)

    Lee, Kye Hyun; Baek, Yong Lak; Chung, Yun Suk

    1994-01-01

    Including the 7 October, 1978, Hongsung earthquake, many earthquakes have occurred in our country. The Korean peninsular is no longer a safety zone against earthquakes, and there are possibilities of the damage they cause. So therefore, it is essential to verify the safety of the safety-related facilities in the event of an earthquake. If an earthquake occurs, seismic instrumentation provides information on the vibratory ground motion and resultant vibratory responses of representative safety-related structures and equipment so that an evaluation can be made immediately as to whether or not the design response spectra have been exceeded. In this paper, general descriptions of the seismic instrumentation installed in domestic NPPs will be discussed; this includes instrument type and location, the Operating Basis Earthquake (OBE) exceedance criteria, and processing and evaluation of earthquake response data, and items to be studied for further enhancement of post-earthquake evaluation techniques are presented

  17. Scope of radon monitoring for earthquake-studies in India

    International Nuclear Information System (INIS)

    Virk, H.S.

    1994-01-01

    In India, there is scope for investigating and exploiting radon as a precursor for earthquakes and for exploration of hydrocarbon deposits. This report mainly deals with the investigations carried out in Kangra and Chamba valleys of Himachal Pradesh under Himalayan Seismicity Project of Department of Science and Technology, Govt. of India. 20 refs., 4 figs., 1 tab

  18. Traumatic experiences and mental health consequences among child survivors of the 2008 Sichuan earthquake: a community-based follow-up study

    Directory of Open Access Journals (Sweden)

    Jia Zhaobao

    2013-02-01

    Full Text Available Abstract Background The study was implemented to examine the relationship between traumatic experiences and longitudinal development of mental health for children and adolescents who survived the 2008 Sichuan earthquake. Methods Using the method of multistage systematic sampling, 596 children aged between 8 and 16 years were randomly selected from severely affected areas of the earthquake. These children were interviewed with standardized instruments of posttraumatic stress disorder (PTSD and depression at the 15th month after the earthquake, and re-interviewed at the 36th month. Results From the initial to the follow-up assessments, there were no significant changes in both PTSD and depression scores. In addition, no significant change was found on the overall prevalence rates of the symptoms: from 12.4% to 10.7% for PTSD, from 13.9% to 13.5% for depression, and from 4.2% to 4.7% for their co-occurrence. The study also indicated that the earthquake might have a delayed impact on the psychosocial functioning of children and adolescents who were not directly affected by the disaster. Conclusions For child and adolescent survivors of the earthquake, symptoms of PTSD and depression seemed to persist over time. The finding that children reduced their use of mental health services raised great concerns over how to fulfill the unmet psychological needs of these children. More mental health interventions should be allocated to children who had elevated risk for developing persistent course of the symptoms.

  19. Assessing Households Preparedness for Earthquakes: An Exploratory Study in the Development of a Valid and Reliable Persian-version Tool.

    Science.gov (United States)

    Ardalan, Ali; Sohrabizadeh, Sanaz

    2016-02-25

    Iran is placed among countries suffering from the highest number of earthquake casualties. Household preparedness, as one component of risk reduction efforts, is often supported in quake-prone areas. In Iran, lack of a valid and reliable household preparedness tool was reported by previous disaster studies. This study is aimed to fill this gap by developing a valid and reliable tool for assessing household preparedness in the event of an earthquake.  This survey was conducted through three phases including literature review and focus group discussions with the participation of eight key informants, validity measurements and reliability measurements. Field investigation was completed with the participation of 450 households within three provinces of Iran. Content validity, construct validity, the use of factor analysis; internal consistency using Cronbach's alpha coefficient, and test-retest reliability were carried out to develop the tool.  Based on the CVIs, ranging from 0.80 to 0.100, and exploratory factor analysis with factor loading of more than 0.5, all items were valid. The amount of Cronbach's alpha (0.7) and test-retest examination by Spearman correlations indicated that the scale was also reliable. The final instrument consisted of six categories and 18 questions including actions at the time of earthquakes, nonstructural safety, structural safety, hazard map, communications, drill, and safety skills.  Using a Persian-version tool that is adjusted to the socio-cultural determinants and native language may result in more trustful information on earthquake preparedness. It is suggested that disaster managers and researchers apply this tool in their future household preparedness projects. Further research is needed to make effective policies and plans for transforming preparedness knowledge into behavior.

  20. Instruments

    International Nuclear Information System (INIS)

    Buehrer, W.

    1996-01-01

    The present paper mediates a basic knowledge of the most commonly used experimental techniques. We discuss the principles and concepts necessary to understand what one is doing if one performs an experiment on a certain instrument. (author) 29 figs., 1 tab., refs

  1. A study of earthquake-induced building detection by object oriented classification approach

    Science.gov (United States)

    Sabuncu, Asli; Damla Uca Avci, Zehra; Sunar, Filiz

    2017-04-01

    Among the natural hazards, earthquakes are the most destructive disasters and cause huge loss of lives, heavily infrastructure damages and great financial losses every year all around the world. According to the statistics about the earthquakes, more than a million earthquakes occur which is equal to two earthquakes per minute in the world. Natural disasters have brought more than 780.000 deaths approximately % 60 of all mortality is due to the earthquakes after 2001. A great earthquake took place at 38.75 N 43.36 E in the eastern part of Turkey in Van Province on On October 23th, 2011. 604 people died and about 4000 buildings seriously damaged and collapsed after this earthquake. In recent years, the use of object oriented classification approach based on different object features, such as spectral, textural, shape and spatial information, has gained importance and became widespread for the classification of high-resolution satellite images and orthophotos. The motivation of this study is to detect the collapsed buildings and debris areas after the earthquake by using very high-resolution satellite images and orthophotos with the object oriented classification and also see how well remote sensing technology was carried out in determining the collapsed buildings. In this study, two different land surfaces were selected as homogenous and heterogeneous case study areas. In the first step of application, multi-resolution segmentation was applied and optimum parameters were selected to obtain the objects in each area after testing different color/shape and compactness/smoothness values. In the next step, two different classification approaches, namely "supervised" and "unsupervised" approaches were applied and their classification performances were compared. Object-based Image Analysis (OBIA) was performed using e-Cognition software.

  2. Study of structures vulnerability with respect to near and distant earthquakes

    International Nuclear Information System (INIS)

    Lopes, E.

    1998-06-01

    Today, according to the fundamental safety rules edited by the French institute of nuclear protection and safety (IPSN), para-seismic structures must be dimensioned in order to withstand the probable near and distant earthquakes. Classical dimensioning tools, like the linear analysis of the elastic response spectrum of an oscillator, show that nearby earthquakes are more damaging for structures. However, experience feedback seems to demonstrate the contrary. The aim of this study is to make a comparison between the damaging effects of nearby and distant earthquakes. Thus, other comparison criteria were defined in order to take into account new parameters and to fit with the experience feedback. In a first part, the difference between nearby and distant earthquakes is explained. Then, after a presentation of the limits of the existing dimensioning tools, the new calculation means are defined and presented with their results. These new methods take into account the inelastic property of the structures. (J.S.)

  3. An Experimental Study of a Midbroken 2-Bay 6-Storey Reinforced Concrete Frame subject to Earthquakes

    DEFF Research Database (Denmark)

    Skjærbæk, P. S.; Taskin, B.; Kirkegaard, Poul Henning

    1997-01-01

    A 2-bay, 6-storey model test reinforced concrete frame (scale 1:5) subjected to sequential earthquakes of increasing magnitude is considered in this paper. The frame was designed with a weak storey, in which the columns are weakened by using thinner and weaker reinforcement bars. The aim of the w......A 2-bay, 6-storey model test reinforced concrete frame (scale 1:5) subjected to sequential earthquakes of increasing magnitude is considered in this paper. The frame was designed with a weak storey, in which the columns are weakened by using thinner and weaker reinforcement bars. The aim...... of the work is to study global response to a damaging strong motion earthquake event of such buildings. Special emphasis is put on examining to what extent damage in the weak storey can be identified from global response measurements during an earthquake where the structure survives, and what level...

  4. Impact of average household income and damage exposure on post-earthquake distress and functioning: A community study following the February 2011 Christchurch earthquake.

    OpenAIRE

    Dorahy, Martin J.; Rowlands, Amy; Renouf, Charlotte; Hanna, Donncha; Britt, Eileen; Carter, Janet D.

    2015-01-01

    Post-traumatic stress, depression and anxiety symptoms are common outcomes following earthquakes, and may persist for months and years. This study systematically examined the impact of neighbourhood damage exposure and average household income on psychological distress and functioning in 600 residents of Christchurch, New Zealand, 4–6 months after the fatal February, 2011 earthquake. Participants were from highly affected and relatively unaffected suburbs in low, medium and high average house...

  5. The Source Inversion Validation (SIV) Initiative: A Collaborative Study on Uncertainty Quantification in Earthquake Source Inversions

    Science.gov (United States)

    Mai, P. M.; Schorlemmer, D.; Page, M.

    2012-04-01

    Earthquake source inversions image the spatio-temporal rupture evolution on one or more fault planes using seismic and/or geodetic data. Such studies are critically important for earthquake seismology in general, and for advancing seismic hazard analysis in particular, as they reveal earthquake source complexity and help (i) to investigate earthquake mechanics; (ii) to develop spontaneous dynamic rupture models; (iii) to build models for generating rupture realizations for ground-motion simulations. In applications (i - iii), the underlying finite-fault source models are regarded as "data" (input information), but their uncertainties are essentially unknown. After all, source models are obtained from solving an inherently ill-posed inverse problem to which many a priori assumptions and uncertain observations are applied. The Source Inversion Validation (SIV) project is a collaborative effort to better understand the variability between rupture models for a single earthquake (as manifested in the finite-source rupture model database) and to develop robust uncertainty quantification for earthquake source inversions. The SIV project highlights the need to develop a long-standing and rigorous testing platform to examine the current state-of-the-art in earthquake source inversion, and to develop and test novel source inversion approaches. We will review the current status of the SIV project, and report the findings and conclusions of the recent workshops. We will briefly discuss several source-inversion methods, how they treat uncertainties in data, and assess the posterior model uncertainty. Case studies include initial forward-modeling tests on Green's function calculations, and inversion results for synthetic data from spontaneous dynamic crack-like strike-slip earthquake on steeply dipping fault, embedded in a layered crustal velocity-density structure.

  6. MANU. Instrumentation of Buffer Demo. Preliminary Study

    International Nuclear Information System (INIS)

    Laaksonen, R.

    2010-01-01

    The purpose of this work is to describe feasible measuring and monitoring alternatives which can be used, if needed, in medium to full scale nuclear waste repository deposition hole mock-up tests. The focus of the work was to determine what variables can actually be measured, how to achieve the measurements and what kind of demands comes from the modelling, scientific, and technical points of view. This project includes a review of the previous waste repository mock-up tests carried out in several European countries such as Belgium, Czech Republic, Spain and Sweden. Also information was gathered by interviewing domestic and foreign scientists specialized in the fields of measurement instrumentation and related in-situ and laboratory work. On the basis of this review, recommendations were developed for the necessary actions needed to be done from the instrumentation point of view for future tests. It is possible to measure and monitor the processes going on in a deposition hole in-situ conditions. The data received during a test in real repository conditions enables to follow the processes and to verify the hypothesis made on the behaviour of various components of the repository: buffer, canister, rock and backfill. Because full scale testing is expensive, the objectives and hypothesis must be carefully set and the test itself with its instrumentation must serve very specific objectives. The main purpose of mock-up tests is to verify that the conditions surrounding the canister are according to the design requirements. A whole mock-up test and demonstration process requires a lot of time and effort. The instrumentation part of the work must also start at early stages to ensure that the instrumentation itself will not become bottlenecked nor suffer from low quality solutions. The planning of the instrumentation work could be done in collaboration with foreign scientists which have participated to previous instrumentation projects. (orig.)

  7. Study on post-earthquake plant evaluation and communication (Annual safety research report, JFY 2010)

    International Nuclear Information System (INIS)

    Iijima, Toru; Taoka, Hideto; Yamada, Hiroyuki; Sano, Kyoko

    2011-01-01

    The aims of this study are to establish a post-earthquake plant evaluation method and to develop a communication system for the improving seismic safety regulations as well as encouraging public communication. The Miyagiken-oki earthquake in 2005, Onagawa Nuclear Power Plant shut down automatically. Subsequently, JNES started development of post-earthquake plant evaluation and communication system based on the experience of the cross-check analysis for Onagawa Nuclear Power Plant. The Niigata-ken Chuetsu-oki Earthquake in 2007, the plant situation was not transmitted promptly. The loss of information sharing between local community and related organizations caused the public anxiety. The importance of plant information transmission as well as seismic information gathering were recognized. The proposal for the solution of the information issues were performed by government committee. In this study, the evaluation method for soundness of the main structure and equipment after earthquake event were updated. Moreover, procedure of the post-earthquake plant soundness evaluation and multi-functional seismic information system were developed. In addition, the implementation strategy of the easy-to -understand information dissemination to the public and transparent communication methodology was examined by the Industry-Academia-Government cooperation in the Kashiwazaki-Kariwa region. (author)

  8. Road Surfaces And Earthquake Engineering: A Theoretical And Experimental Study

    International Nuclear Information System (INIS)

    Pratico, Filippo Giammaria

    2008-01-01

    As is well known, road surfaces greatly affect vehicle-road interaction. As a consequence, road surfaces have a paramount influence on road safety and pavement management systems. On the other hand, earthquakes produce deformations able to modify road surface structure, properties and performance. In the light of these facts, the main goal of this paper has been confined into the modelling of road surface before, during and after the seismic event. The fundamentals of road surface texture theory have been stated in a general formulation. Models in the field of road profile generation and theoretical properties, before, during and after the earthquake, have been formulated and discussed. Practical applications can be hypothesised in the field of vehicle-road interaction as a result of road surface texture derived from deformations and accelerations caused by seismic or similar events

  9. A Statistical Study on VLF Subionospheric Perturbations Associated with Major Earthquakes: A View from Focal Mechanism

    Science.gov (United States)

    Kawano, T.; Tatsuta, K.; Hobara, Y.

    2015-12-01

    Continuous monitoring of signal amplitudes of worldwide VLF transmitters is a powerful tool to study the lower ionospheric condition. Although, lower ionospheric perturbations prior to some of the major earthquakes have been reported for years, their occurrence and coupling mechanism between the ground and overlaying ionosphere prior to the earthquakes are not clear yet. In this paper, we carried out a statistical analysis based on the nighttime averaged signal amplitude data from the UEC's VLF/LF transmitter observation network. Two hundred forty three earthquakes were occurred within the 5th Fresnel zone of transmitter-receiver paths around Japan during the time period of 2007 to 2012. These earthquakes were characterized into three different groups based on the Centroid-Moment-Tensor (CMT) solution such as reverse fault type, normal fault type and stress slip type. The ionospheric anomaly was identified by a large change in the VLF/LF amplitude during nighttime. As a result, we found the ionospheric perturbations associated with both ground and sea earthquakes. Remarkably, the reverse fault type earthquakes have the highest occurrence rate of ionospheric perturbation among the three types both for sea (41%) and ground events (61%). The occurrence rates for normal type fault are 35% and 56% for sea and ground earthquakes respectively and the same for stress slip type are 39% and 20% for sea and ground earthquakes respectively. In both cases the occurrence rates are smaller than the reverse fault type. The clear difference of occurrence rate of the ionospheric perturbations may indicate that the coupling efficiency of seismic activity into the overlaying ionosphere is controlled by the pressure in the earth's crust. This gives us further physical insight of Lithosphere-Atmosphere-Ionosphere (LAI) coupling processes.

  10. Instrumentation

    International Nuclear Information System (INIS)

    Muehllehner, G.; Colsher, J.G.

    1982-01-01

    This chapter reviews the parameters which are important to positron-imaging instruments. It summarizes the options which various groups have explored in designing tomographs and the methods which have been developed to overcome some of the limitations inherent in the technique as well as in present instruments. The chapter is not presented as a defense of positron imaging versus single-photon or other imaging modality, neither does it contain a description of various existing instruments, but rather stresses their common properties and problems. Design parameters which are considered are resolution, sampling requirements, sensitivity, methods of eliminating scattered radiation, random coincidences and attenuation. The implementation of these parameters is considered, with special reference to sampling, choice of detector material, detector ring diameter and shielding and variations in point spread function. Quantitation problems discussed are normalization, and attenuation and random corrections. Present developments mentioned are noise reduction through time-of-flight-assisted tomography and signal to noise improvements through high intrinsic resolution. Extensive bibliography. (U.K.)

  11. Psychological distress among Bam earthquake survivors in Iran: a population-based study.

    Science.gov (United States)

    Montazeri, Ali; Baradaran, Hamid; Omidvari, Sepideh; Azin, Seyed Ali; Ebadi, Mehdi; Garmaroudi, Gholamreza; Harirchi, Amir Mahmood; Shariati, Mohammad

    2005-01-11

    An earthquake measuring 6.3 on the Richter scale struck the city of Bam in Iran on the 26th of December 2003 at 5.26 A.M. It was devastating, and left over 40,000 dead and around 30,000 injured. The profound tragedy of thousands killed has caused emotional and psychological trauma for tens of thousands of people who have survived. A study was carried out to assess psychological distress among Bam earthquake survivors and factors associated with severe mental health in those who survived the tragedy. This was a population-based study measuring psychological distress among the survivors of Bam earthquake in Iran. Using a multi-stage stratified sampling method a random sample of individuals aged 15 years and over living in Bam were interviewed. Psychological distress was measured using the 12-item General Health Questionnaire (GHQ-12). In all 916 survivors were interviewed. The mean age of the respondents was 32.9 years (SD = 12.4), mostly were males (53%), married (66%) and had secondary school education (50%). Forty-one percent reported they lost 3 to 5 members of their family in the earthquake. In addition the findings showed that 58% of the respondents suffered from severe mental health as measured by the GHQ-12 and this was three times higher than reported psychological distress among the general population. There were significant differences between sub-groups of the study sample with regard to their psychological distress. The results of the logistic regression analysis also indicated that female gender; lower education, unemployment, and loss of family members were associated with severe psychological distress among earthquake victims. The study findings indicated that the amount of psychological distress among earthquake survivors was high and there is an urgent need to deliver mental health care to disaster victims in local medical settings and to reduce negative health impacts of the earthquake adequate psychological counseling is needed for those who

  12. Earthquake activity in Sweden. Study in connection with a proposed nuclear waste repository in Forsmark or Oskarshamn

    International Nuclear Information System (INIS)

    Boedvarsson, Reynir; Lund, Bjoern; Roberts, Roland; Slunga, Ragnar

    2006-02-01

    The aim of this report is to evaluate the risks for future earthquakes in the vicinity of the proposed nuclear waste repository sites at Forsmark and Oskarshamn. Time periods of 100 and 1,000 years will be considered, which implies that the focus of this study is on an evaluation of the current, general situation in the region. Major events on a longer time scale, such as an ice-age, will only be briefly considered. Earthquakes are products of ongoing deformations within the Earth and this report will, therefore, concentrate on the current state of knowledge about deformations in the region. As earthquakes are our most important source of information about deformations at depth in the crust, we will focus on the available seismic data using the Nordic earthquake catalog maintained at the Institute of Seismology, Helsinki University, and the recent data from the new Swedish National Seismic Network. Direct measurements of surface deformation using the Global Positioning System will also be utilized in the analysis. Sweden is a low seismicity area, with most earthquakes being observed in the south-west, around Lake Vaenern, along the north-east coast and in Norrbotten. South-eastern Sweden is on the contrary relatively inactive. Seismicity is also, generally, episodic in time which together with the short period of instrumental observation, approximately 100 years, makes our knowledge about the activity far from complete. Although very large earthquakes (magnitude about 8) have occurred in Sweden, it is generally agreed that these were connected to the late stages of deglaciation at the end of the previous ice-age. At the time scales considered in this report, inferences from current seismicity is of more relevance. This data suggests that we should expect at least one magnitude 5 earthquake in our region every century and one magnitude 6 earthquake every one thousand years. In order to illustrate the effects of static and dynamic deformation from a magnitude 5

  13. Sensitivity studies of a PCV under earthquake loading conditions

    International Nuclear Information System (INIS)

    Maraslioglu, B.; Shamshiri, I.

    1987-01-01

    The results point out the special sensitivity of the modeling and the time history method analyses. Due to the lack of more precise general statements in literature and regulations which should help to find an otpimal design, the analyst is challenged to make much efforts in finding realistic, conservative, not overestimated results. For the purpose of more precise data due to the temporal combination in time history method he has to abandon the security supplied by enveloped, smoothed and broadened spectra in response spectrum method analysis (RSMA). It is therefore advisable to prefer RSMA or to perform several calculations with variations of frequency, ground shear modulus and earthquake loading condition. (orig./HP)

  14. Echo-sounding method aids earthquake hazard studies

    Science.gov (United States)

    ,

    1995-01-01

    Dramatic examples of catastrophic damage from an earthquake occurred in 1989, when the M 7.1 Lorna Prieta rocked the San Francisco Bay area, and in 1994, when the M 6.6 Northridge earthquake jolted southern California. The surprising amount and distribution of damage to private property and infrastructure emphasizes the importance of seismic-hazard research in urbanized areas, where the potential for damage and loss of life is greatest. During April 1995, a group of scientists from the U.S. Geological Survey and the University of Tennessee, using an echo-sounding method described below, is collecting data in San Antonio Park, California, to examine the Monte Vista fault which runs through this park. The Monte Vista fault in this vicinity shows evidence of movement within the last 10,000 years or so. The data will give them a "picture" of the subsurface rock deformation near this fault. The data will also be used to help locate a trench that will be dug across the fault by scientists from William Lettis & Associates.

  15. Victims' time discounting 2.5 years after the Wenchuan earthquake: an ERP study.

    Directory of Open Access Journals (Sweden)

    Jin-Zhen Li

    Full Text Available Time discounting refers to the fact that the subjective value of a reward decreases as the delay until its occurrence increases. The present study investigated how time discounting has been affected in survivors of the magnitude-8.0 Wenchuan earthquake that occurred in China in 2008.Nineteen earthquake survivors and 22 controls, all school teachers, participated in the study. Event-related brain potentials (ERPs for time discounting tasks involving gains and losses were acquired in both the victims and controls.The behavioral data replicated our previous findings that delayed gains were discounted more steeply after a disaster. ERP results revealed that the P200 and P300 amplitudes were increased in earthquake survivors. There was a significant group (earthquake vs. non-earthquake × task (gain vs. loss interaction for the N300 amplitude, with a marginally significantly reduced N300 for gain tasks in the experimental group, which may suggest a deficiency in inhibitory control for gains among victims.The results suggest that post-disaster decisions might involve more emotional (System 1 and less rational thinking (System 2 in terms of a dual-process model of decision making. The implications for post-disaster intervention and management are also discussed.

  16. Victims' time discounting 2.5 years after the Wenchuan earthquake: an ERP study.

    Science.gov (United States)

    Li, Jin-Zhen; Gui, Dan-Yang; Feng, Chun-Liang; Wang, Wen-Zhong; Du, Bo-Qi; Gan, Tian; Luo, Yue-Jia

    2012-01-01

    Time discounting refers to the fact that the subjective value of a reward decreases as the delay until its occurrence increases. The present study investigated how time discounting has been affected in survivors of the magnitude-8.0 Wenchuan earthquake that occurred in China in 2008. Nineteen earthquake survivors and 22 controls, all school teachers, participated in the study. Event-related brain potentials (ERPs) for time discounting tasks involving gains and losses were acquired in both the victims and controls. The behavioral data replicated our previous findings that delayed gains were discounted more steeply after a disaster. ERP results revealed that the P200 and P300 amplitudes were increased in earthquake survivors. There was a significant group (earthquake vs. non-earthquake) × task (gain vs. loss) interaction for the N300 amplitude, with a marginally significantly reduced N300 for gain tasks in the experimental group, which may suggest a deficiency in inhibitory control for gains among victims. The results suggest that post-disaster decisions might involve more emotional (System 1) and less rational thinking (System 2) in terms of a dual-process model of decision making. The implications for post-disaster intervention and management are also discussed.

  17. Study on post-earthquake plant evaluation and communication (Annual safety research report, JFY 2011)

    International Nuclear Information System (INIS)

    2012-01-01

    The aims of this study are to establish a post-earthquake plant evaluation method and to develop a communication system for the improving seismic safety regulations as well as encouraging public communication. The Miyagiken-oki earthquake in 2005, Onagawa Nuclear Power Plant shut down automatically. Subsequently, JNES started development of post-earthquake plant evaluation and communication system based on the experience of the cross-check analysis for Onagawa Nuclear Power Plant. The Niigata-ken Chuetsu-oki Earthquake in 2007, the plant situation was not transmitted promptly. The loss of information sharing between local community and related organizations caused the public anxiety. The importance of plant information transmission as well as seismic information gathering were recognized. The proposal for the solution of the information issues were performed by government committee, In this study the evaluation method for soundness of the main structure and equipment after earthquake event were updated. Moreover, information dissemination to the public and transparent communication methodology was examined by the Industry-Academia-Government cooperation in the Kashiwazaki-Kariwa region. (author)

  18. Comparing population exposure to multiple Washington earthquake scenarios for prioritizing loss estimation studies

    Science.gov (United States)

    Wood, Nathan J.; Ratliff, Jamie L.; Schelling, John; Weaver, Craig S.

    2014-01-01

    Scenario-based, loss-estimation studies are useful for gauging potential societal impacts from earthquakes but can be challenging to undertake in areas with multiple scenarios and jurisdictions. We present a geospatial approach using various population data for comparing earthquake scenarios and jurisdictions to help emergency managers prioritize where to focus limited resources on data development and loss-estimation studies. Using 20 earthquake scenarios developed for the State of Washington (USA), we demonstrate how a population-exposure analysis across multiple jurisdictions based on Modified Mercalli Intensity (MMI) classes helps emergency managers understand and communicate where potential loss of life may be concentrated and where impacts may be more related to quality of life. Results indicate that certain well-known scenarios may directly impact the greatest number of people, whereas other, potentially lesser-known, scenarios impact fewer people but consequences could be more severe. The use of economic data to profile each jurisdiction’s workforce in earthquake hazard zones also provides additional insight on at-risk populations. This approach can serve as a first step in understanding societal impacts of earthquakes and helping practitioners to efficiently use their limited risk-reduction resources.

  19. Geosphere Stability for long-term isolation of radioactive waste. Case study for hydrological change with earthquakes and faulting

    International Nuclear Information System (INIS)

    Niwa, Masakazu

    2016-01-01

    Appropriate estimation and safety assessment for long-term changes in geological environment are essential to an improvement of reliability for geological disposal. Specifically, study on faults is important for understanding regional groundwater flow as well as an assessment as a trigger of future earthquakes. Here, possibility of changes in permeability of faulted materials induced by earthquakes was examined based on monitoring data of groundwater pressure before and after the 2011 off the Pacific coast of Tohoku Earthquake. (author)

  20. Study of near-source earthquake effects on flexible buried pipes

    Science.gov (United States)

    Davis, Craig Alan

    2000-10-01

    An investigation is carried out, using strong ground motion recordings, field measurements, and new analytical models, on large diameter flexible buried pipes shaken in the 1994 Northridge earthquake near field. Case studies are presented for corrugated metal pipes (CMP) in the Van Norman Complex (VNC) vicinity in Los Angeles, California. In 1994 the VNC yielded an unprecedented number of strong motion recordings with high acceleration and velocity. These recordings contain forward directivity pulses and provided the largest velocity ever instrumentally recorded (180 cm/s). The recorded motions were significantly different in the longitudinal and transverse directions and had approximately half the amplitude at the VNC center than on the north and south ends. The seismic performances of 61 underground CMPs are presented, beginning with detailed studies of a 2.4 m diameter pipe that suffered complete lateral buckling collapse at the Lower San Fernando Dam (LSFD). The case histories identify factors controlling large diameter CMP seismic performances that are incorporated into several newly developed models for the analysis and design of buried structures. Each model progressively improves the understanding of buried pipe behavior. Simple acceleration- and strain-based pseudo-static models are initially developed to identify main causes for CMP damage. Elasto-dynamic models for transverse SV waves are later used to understand flexible pipe response in the frequency and time domains and are compared with existing solutions. Finally, pseudo-static models, which analyze pipe responses in terms of free-field strains, are formulated to account for dynamic amplification, non-vertical wave incidence, soil layering, and trench backfill soil stiffness. The elastic models are used to investigate soil-pipe interface shear stress and non-linear soil behavior and show that the maximum pipe hoop force is best characterized by assuming no interface slippage. The models explain the

  1. A STUDY ON THE EARTHQUAKE RESPONSE AND EARTHQUAKE RESISTANT DESIGN METHOD OF AN OPEN TYPE WHARF WITH PNEUMATIC CAISSONS

    Science.gov (United States)

    Oishi, Masahiko; Nagao, Takashi; Shigeki, Kouji; Ouchi, Masatoshi; Sato, Yuske; Kinomiya, Osamu

    Seismic response of an open type wharf with pneumatic caisson was clarified using a dynamic finite element method. As a result, rocking behavior of caisson foundations were observed and applicability of a frame model analysis to the earthquake resistant design of a wharf was suggested. Authors proposed the framework of earthquake resistant design method of the wharf including the evaluation method of response acceleration of the wharf.

  2. Application of geostatistical simulation to compile seismotectonic provinces based on earthquake databases (case study: Iran)

    Science.gov (United States)

    Jalali, Mohammad; Ramazi, Hamidreza

    2018-04-01

    This article is devoted to application of a simulation algorithm based on geostatistical methods to compile and update seismotectonic provinces in which Iran has been chosen as a case study. Traditionally, tectonic maps together with seismological data and information (e.g., earthquake catalogues, earthquake mechanism, and microseismic data) have been used to update seismotectonic provinces. In many cases, incomplete earthquake catalogues are one of the important challenges in this procedure. To overcome this problem, a geostatistical simulation algorithm, turning band simulation, TBSIM, was applied to make a synthetic data to improve incomplete earthquake catalogues. Then, the synthetic data was added to the traditional information to study the seismicity homogeneity and classify the areas according to tectonic and seismic properties to update seismotectonic provinces. In this paper, (i) different magnitude types in the studied catalogues have been homogenized to moment magnitude (Mw), and earthquake declustering was then carried out to remove aftershocks and foreshocks; (ii) time normalization method was introduced to decrease the uncertainty in a temporal domain prior to start the simulation procedure; (iii) variography has been carried out in each subregion to study spatial regressions (e.g., west-southwestern area showed a spatial regression from 0.4 to 1.4 decimal degrees; the maximum range identified in the azimuth of 135 ± 10); (iv) TBSIM algorithm was then applied to make simulated events which gave rise to make 68,800 synthetic events according to the spatial regression found in several directions; (v) simulated events (i.e., magnitudes) were classified based on their intensity in ArcGIS packages and homogenous seismic zones have been determined. Finally, according to the synthetic data, tectonic features, and actual earthquake catalogues, 17 seismotectonic provinces were introduced in four major classes introduced as very high, high, moderate, and low

  3. The Differences in Source Dynamics Between Intermediate-Depth and Deep EARTHQUAKES:A Comparative Study Between the 2014 Rat Islands Intermediate-Depth Earthquake and the 2015 Bonin Islands Deep Earthquake

    Science.gov (United States)

    Twardzik, C.; Ji, C.

    2015-12-01

    It has been proposed that the mechanisms for intermediate-depth and deep earthquakes might be different. While previous extensive seismological studies suggested that such potential differences do not significantly affect the scaling relationships of earthquake parameters, there has been only a few investigations regarding their dynamic characteristics, especially for fracture energy. In this work, the 2014 Mw7.9 Rat Islands intermediate-depth (105 km) earthquake and the 2015 Mw7.8 Bonin Islands deep (680 km) earthquake are studied from two different perspectives. First, their kinematic rupture models are constrained using teleseismic body waves. Our analysis reveals that the Rat Islands earthquake breaks the entire cold core of the subducting slab defined as the depth of the 650oC isotherm. The inverted stress drop is 4 MPa, compatible to that of intra-plate earthquakes at shallow depths. On the other hand, the kinematic rupture model of the Bonin Islands earthquake, which occurred in a region lacking of seismicity for the past forty years, according to the GCMT catalog, exhibits an energetic rupture within a 35 km by 30 km slip patch and a high stress drop of 24 MPa. It is of interest to note that although complex rupture patterns are allowed to match the observations, the inverted slip distributions of these two earthquakes are simple enough to be approximated as the summation of a few circular/elliptical slip patches. Thus, we investigate subsequently their dynamic rupture models. We use a simple modelling approach in which we assume that the dynamic rupture propagation obeys a slip-weakening friction law, and we describe the distribution of stress and friction on the fault as a set of elliptical patches. We will constrain the three dynamic parameters that are yield stress, background stress prior to the rupture and slip weakening distance, as well as the shape of the elliptical patches directly from teleseismic body waves observations. The study would help us

  4. Relay chatter and operator response after a large earthquake: An improved PRA methodology with case studies

    International Nuclear Information System (INIS)

    Budnitz, R.J.; Lambert, H.E.; Hill, E.E.

    1987-08-01

    The purpose of this project has been to develop and demonstrate improvements in the PRA methodology used for analyzing earthquake-induced accidents at nuclear power reactors. Specifically, the project addresses methodological weaknesses in the PRA systems analysis used for studying post-earthquake relay chatter and for quantifying human response under high stress. An improved PRA methodology for relay-chatter analysis is developed, and its use is demonstrated through analysis of the Zion-1 and LaSalle-2 reactors as case studies. This demonstration analysis is intended to show that the methodology can be applied in actual cases, and the numerical values of core-damage frequency are not realistic. The analysis relies on SSMRP-based methodologies and data bases. For both Zion-1 and LaSalle-2, assuming that loss of offsite power (LOSP) occurs after a large earthquake and that there are no operator recovery actions, the analysis finds very many combinations (Boolean minimal cut sets) involving chatter of three or four relays and/or pressure switch contacts. The analysis finds that the number of min-cut-set combinations is so large that there is a very high likelihood (of the order of unity) that at least one combination will occur after earthquake-caused LOSP. This conclusion depends in detail on the fragility curves and response assumptions used for chatter. Core-damage frequencies are calculated, but they are probably pessimistic because assuming zero credit for operator recovery is pessimistic. The project has also developed an improved PRA methodology for quantifying operator error under high-stress conditions such as after a large earthquake. Single-operator and multiple-operator error rates are developed, and a case study involving an 8-step procedure (establishing feed-and-bleed in a PWR after an earthquake-initiated accident) is used to demonstrate the methodology

  5. Feasibility Study of Earthquake Early Warning in Hawai`i For the Mauna Kea Thirty Meter Telescope

    Science.gov (United States)

    Okubo, P.; Hotovec-Ellis, A. J.; Thelen, W. A.; Bodin, P.; Vidale, J. E.

    2014-12-01

    Earthquakes, including large damaging events, are as central to the geologic evolution of the Island of Hawai`i as its more famous volcanic eruptions and lava flows. Increasing and expanding development of facilities and infrastructure on the island continues to increase exposure and risk associated with strong ground shaking resulting from future large local earthquakes. Damaging earthquakes over the last fifty years have shaken the most heavily developed areas and critical infrastructure of the island to levels corresponding to at least Modified Mercalli Intensity VII. Hawai`i's most recent damaging earthquakes, the M6.7 Kiholo Bay and M6.0 Mahukona earthquakes, struck within seven minutes of one another off of the northwest coast of the island in October 2006. These earthquakes resulted in damage at all thirteen of the telescopes near the summit of Mauna Kea that led to gaps in telescope operations ranging from days up to four months. With the experiences of 2006 and Hawai`i's history of damaging earthquakes, we have begun a study to explore the feasibility of implementing earthquake early warning systems to provide advanced warnings to the Thirty Meter Telescope of imminent strong ground shaking from future local earthquakes. One of the major challenges for earthquake early warning in Hawai`i is the variety of earthquake sources, from shallow crustal faults to deeper mantle sources, including the basal decollement separating the volcanic pile from the ancient oceanic crust. Infrastructure on the Island of Hawai`i may only be tens of kilometers from these sources, allowing warning times of only 20 s or less. We assess the capability of the current seismic network to produce alerts for major historic earthquakes, and we will provide recommendations for upgrades to improve performance.

  6. Ionospheric earthquake precursors

    International Nuclear Information System (INIS)

    Bulachenko, A.L.; Oraevskij, V.N.; Pokhotelov, O.A.; Sorokin, V.N.; Strakhov, V.N.; Chmyrev, V.M.

    1996-01-01

    Results of experimental study on ionospheric earthquake precursors, program development on processes in the earthquake focus and physical mechanisms of formation of various type precursors are considered. Composition of experimental cosmic system for earthquake precursors monitoring is determined. 36 refs., 5 figs

  7. Studies of earthquakes stress drops, seismic scattering, and dynamic triggering in North America

    Science.gov (United States)

    Escudero Ayala, Christian Rene

    I use the Relative Source Time Function (RSTF) method to determine the source properties of earthquakes within southeastern Alaska-northwestern Canada in a first part of the project, and earthquakes within the Denali fault in a second part. I deconvolve a small event P-arrival signal from a larger event by the following method: select arrivals with a tapered cosine window, fast fourier transform to obtain the spectrum, apply water level deconvolution technique, and bandpass filter before inverse transforming the result to obtain the RSTF. I compare the source processes of earthquakes within the area to determine stress drop differences to determine their relation with the tectonic setting of the earthquakes location. Results show an consistency with previous results, stress drop independent of moment implying self-similarity, correlation of stress drop with tectonic regime, stress drop independent of depth, stress drop depends of focal mechanism where strike-slip present larger stress drops, and decreasing stress drop as function of time. I determine seismic wave attenuation in the central western United States using coda waves. I select approximately 40 moderate earthquakes (magnitude between 5.5 and 6.5) located alocated along the California-Baja California, California-Nevada, Eastern Idaho, Gulf of California, Hebgen Lake, Montana, Nevada, New Mexico, off coast of Northern California, off coast of Oregon, southern California, southern Illinois, Vancouver Island, Washington, and Wyoming regions. These events were recorded by the EarthScope transportable array (TA) network from 2005 to 2009. We obtain the data from the Incorporated Research Institutions for Seismology (IRIS). In this study we implement a method based on the assumption that coda waves are single backscattered waves from randomly distributed heterogeneities to calculate the coda Q. The frequencies studied lie between 1 and 15 Hz. The scattering attenuation is calculated for frequency bands centered

  8. Automatic Event Detection and Picking of P, S Seismic Phases for Earthquake Early Warning: A Case Study of the 2008 Wenchuan Earthquake

    Science.gov (United States)

    WANG, Z.; Zhao, B.

    2015-12-01

    We develop an automatic seismic phase arrival detection and picking algorithm for the impending earthquakes occurred with diverse focal mechanisms and depths. The polarization analysis of the three-component seismograms is utilized to distinguish between P and S waves through a sliding time window. When applying the short term average/long term average (STA/LTA) method to the polarized data, we also construct a new characteristics function that can sensitively reflect the changes of signals' amplitude and frequency, providing a better detection for the phase arrival. Then an improved combination method of the higher order statistics and the Akaike information criteria (AIC) picker is applied to the refined signal to lock on the arrival time with a higher degree of accuracy. We test our techniques to the aftershocks of the Ms8.0 Wenchuan earthquake, where hundreds of three-component acceleration records with magnitudes of 4.0 to 6.4 are treated. In comparison to the analyst picks, the results of the proposed detection algorithms are shown to perform well and can be applied from a single instrument within a network of stations for the large seismic events in the Earthquake Early Warning System (EEWS).

  9. Site Effects Study In Athens (greece) Using The 7th September 1999 Earthquake Aftershock Sequence

    Science.gov (United States)

    Serpetsidaki, A.; Sokos, E.

    On 7 September 1999 at 11:56:50 GMT, an earthquake of Mw=5.9 occurred at Athens capital of Greece. The epicenter was located in the Northwest area of Parnitha Moun- tain at 18km distance from the city centre. This earthquake was one of the most de- structive in Greece during the modern times. The intensity of the earthquake reached IX in the Northwest territories of the city and caused the death of 143 people and seri- ous structural damage in many buildings. On the 13th of September the Seismological Laboratory of Patras University, installed a seismic network of 30 stations in order to observe the evolution of the aftershock sequence. This temporary seismic network remained in the area of Attika for 50 days and recorded a significant part of the af- tershock sequence. In this paper we use the high quality recordings of this network to investigate the influence of the surface geology to the seismic motion, on sites within the epicentral area, which suffered the most during this earthquake. We applied the horizontal-to-vertical (H/V) spectral ratio method on noise and on earthquake records and the obtained results exhibit very good agreement. Finally we compare the results with the geological conditions of the study area and the damage distribution. Most of the obtained amplification levels were low with an exemption in the site of Ano Liosia were a significant amount of damage was observed and the results indicate that the earthquake motion was amplified four times. Based on the above we conclude that the damages in the city of Athens were due to source effects rather than site effects.

  10. Study on the fixed point in crustal deformation before strong earthquake

    Science.gov (United States)

    Niu, A.; Li, Y.; Yan, W. Mr

    2017-12-01

    Usually, scholars believe that the fault pre-sliding or expansion phenomenon will be observed near epicenter area before strong earthquake, but more and more observations show that the crust deformation nearby epicenter area is smallest(Zhou, 1997; Niu,2009,2012;Bilham, 2005; Amoruso et al., 2010). The theory of Fixed point t is a branch of mathematics that arises from the theory of topological transformation and has important applications in obvious model analysis. An important precursory was observed by two tilt-meter sets, installed at Wenchuan Observatory in the epicenter area, that the tilt changes were the smallest compared with the other 8 stations around them in one year before the Wenchuan earthquake. To subscribe the phenomenon, we proposed the minimum annual variation range that used as a topological transformation. The window length is 1 year, and the sliding length is 1 day. The convergence of points with minimum annual change in the 3 years before the Wenchuan earthquake is studied. And the results show that the points with minimum deformation amplitude basically converge to the epicenter region before the earthquake. The possible mechanism of fixed point of crustal deformation was explored. Concerning the fixed point of crust deformation, the liquidity of lithospheric medium and the isostasy theory are accepted by many scholars (Bott &Dean, 1973; Merer et al.1988; Molnar et al., 1975,1978; Tapponnier et al., 1976; Wang et al., 2001). To explain the fixed point of crust deformation before earthquakes, we study the plate bending model (Bai, et al., 2003). According to plate bending model and real deformation data, we have found that the earthquake rupture occurred around the extreme point of plate bending, where the velocities of displacement, tilt, strain, gravity and so on are close to zero, and the fixed points are located around the epicenter.The phenomenon of fixed point of crust deformation is different from former understandings about the

  11. Miami's Tequesta Site: Could It Be a Native American Study Site For Natural Periodicities Associated With Tornados, Hurricanes, or Earthquakes?

    Science.gov (United States)

    Mac Dougall, Jean S.; Mc Leod, David M.; Mc Leod, Roger D.

    2002-10-01

    Florida invested in preserving the Tequesta Indians' "Stonehenge-like" site along the Miami River. Direct observation, and telecast reports, show that a strong association exists between this area and Native American place names, hurricanes, tornados, a waterspout, and other nearby phenomena. Electromagnetic stimulation of human nervous systems in areas like these, discernable by appropriately sensitive individuals when these types of events occur, could plausibly account for some correct "predictions" of events like earthquakes. Various sensory modalities may be activated there. It may be important to understand other historic aspects associated with cultural artifacts like Miami's Tequesta remains. If it also generates instrumentally detectable signals that correlate with visual, "auditory," or nerve ending "tinglings" like those cited by the psychiatrist Arthur Guirdham in books like his Obsessions, applied physicists could partly vindicate the investment and also provide a net return. Society and comparative religious study may benefit.

  12. Impact of average household income and damage exposure on post-earthquake distress and functioning: A community study following the February 2011 Christchurch earthquake.

    Science.gov (United States)

    Dorahy, Martin J; Rowlands, Amy; Renouf, Charlotte; Hanna, Donncha; Britt, Eileen; Carter, Janet D

    2015-08-01

    Post-traumatic stress, depression and anxiety symptoms are common outcomes following earthquakes, and may persist for months and years. This study systematically examined the impact of neighbourhood damage exposure and average household income on psychological distress and functioning in 600 residents of Christchurch, New Zealand, 4-6 months after the fatal February, 2011 earthquake. Participants were from highly affected and relatively unaffected suburbs in low, medium and high average household income areas. The assessment battery included the Acute Stress Disorder Scale, the depression module of the Patient Health Questionnaire (PHQ-9), and the Generalized Anxiety Disorder Scale (GAD-7), along with single item measures of substance use, earthquake damage and impact, and disruptions in daily life and relationship functioning. Controlling for age, gender and social isolation, participants from low income areas were more likely to meet diagnostic cut-offs for depression and anxiety, and have more severe anxiety symptoms. Higher probabilities of acute stress, depression and anxiety diagnoses were evident in affected versus unaffected areas, and those in affected areas had more severe acute stress, depression and anxiety symptoms. An interaction between income and earthquake effect was found for depression, with those from the low and medium income affected suburbs more depressed. Those from low income areas were more likely, post-earthquake, to start psychiatric medication and increase smoking. There was a uniform increase in alcohol use across participants. Those from the low income affected suburb had greater general and relationship disruption post-quake. Average household income and damage exposure made unique contributions to earthquake-related distress and dysfunction. © 2014 The British Psychological Society.

  13. Posttraumatic Stress, Depression, and Coping Following the 2015 Nepal Earthquake: A Study on Adolescents.

    Science.gov (United States)

    Sharma, Asmita; Kar, Nilamadhab

    2018-05-24

    The study aimed to gather data on posttraumatic stress and depression in adolescents following the 2015 Nepal earthquake and explore the adolescents' coping strategies. In a questionnaire-based, cross-sectional study about 1 year after the earthquake, adolescents in two districts with different degrees of impact were evaluated for disaster experience, coping strategies, and symptoms of posttraumatic stress and depression measured with the Child Posttraumatic Stress Scale and the Depression Self Rating Scale. In the studied sample (N=409), the estimated prevalence of posttraumatic stress disorder (PTSD) (43.3%) and depression (38.1%) was considerable. Prevalence of PTSD was significantly higher in the more affected area (49.0% v 37.9%); however, the prevalence figures were comparable in adolescents who reported a stress. The prevalence of depression was comparable. Female gender, joint family, financial problems, displacement, injury or being trapped in the earthquake, damage to livelihood, and fear of death were significantly associated with a probable PTSD diagnosis. Various coping strategies were used: talking to others, praying, helping others, hoping for the best, and some activities were common. Drug abuse was rare. Most of the coping strategies were comparable among the clinical groups. A considerable proportion of adolescents had posttraumatic stress and depression 1 year after the earthquake. There is a need for clinical interventions and follow-up studies regarding the outcome. Disaster Med Public Health Preparedness. 2018;page 1 of 7.

  14. Stress modulation of earthquakes: A study of long and short period stress perturbations and the crustal response

    Science.gov (United States)

    Johnson, Christopher W.

    Decomposing fault mechanical processes advances our understanding of active fault systems and properties of the lithosphere, thereby increasing the effectiveness of seismic hazard assessment and preventative measures implemented in urban centers. Along plate boundaries earthquakes are inevitable as tectonic forces reshape the Earth's surface. Earthquakes, faulting, and surface displacements are related systems that require multidisciplinary approaches to characterize deformation in the lithosphere. Modern geodetic instrumentation can resolve displacements to millimeter precision and provide valuable insight into secular deformation in near real-time. The expansion of permanent seismic networks as well as temporary deployments allow unprecedented detection of microseismic events that image fault interfaces and fracture networks in the crust. The research presented in this dissertation is at the intersection of seismology and geodesy to study the Earth's response to transient deformation and explores research questions focusing on earthquake triggering, induced seismicity, and seasonal loading while utilizing seismic data, geodetic data, and modeling tools. The focus is to quantify stress changes in the crust, explore seismicity rate variations and migration patterns, and model crustal deformation in order to characterize the evolving state of stress on faults and the migration of fluids in the crust. The collection of problems investigated all investigate the question: Why do earthquakes nucleate following a low magnitude stress perturbation? Answers to this question are fundamental to understanding the time dependent failure processes of the lithosphere. Dynamic triggering is the interaction of faults and triggering of earthquakes represents stress transferring from one system to another, at both local and remote distances [Freed, 2005]. The passage of teleseismic surface waves from the largest earthquakes produce dynamic stress fields and provides a natural

  15. CSEP-Japan: The Japanese node of the collaboratory for the study of earthquake predictability

    Science.gov (United States)

    Yokoi, S.; Tsuruoka, H.; Nanjo, K.; Hirata, N.

    2011-12-01

    Collaboratory for the Study of Earthquake Predictability (CSEP) is a global project of earthquake predictability research. The final goal of this project is to have a look for the intrinsic predictability of the earthquake rupture process through forecast testing experiments. The Earthquake Research Institute, the University of Tokyo joined the CSEP and started the Japanese testing center called as CSEP-Japan. This testing center constitutes an open access to researchers contributing earthquake forecast models for applied to Japan. A total of 91 earthquake forecast models were submitted on the prospective experiment starting from 1 November 2009. The models are separated into 4 testing classes (1 day, 3 months, 1 year and 3 years) and 3 testing regions covering an area of Japan including sea area, Japanese mainland and Kanto district. We evaluate the performance of the models in the official suite of tests defined by the CSEP. The experiments of 1-day, 3-month, 1-year and 3-year forecasting classes were implemented for 92 rounds, 4 rounds, 1round and 0 round (now in progress), respectively. The results of the 3-month class gave us new knowledge concerning statistical forecasting models. All models showed a good performance for magnitude forecasting. On the other hand, observation is hardly consistent in space-distribution with most models in some cases where many earthquakes occurred at the same spot. Throughout the experiment, it has been clarified that some properties of the CSEP's evaluation tests such as the L-test show strong correlation with the N-test. We are now processing to own (cyber-) infrastructure to support the forecast experiment as follows. (1) Japanese seismicity has changed since the 2011 Tohoku earthquake. The 3rd call for forecasting models was announced in order to promote model improvement for forecasting earthquakes after this earthquake. So, we provide Japanese seismicity catalog maintained by JMA for modelers to study how seismicity

  16. Uncertainties in Earthquake Loss Analysis: A Case Study From Southern California

    Science.gov (United States)

    Mahdyiar, M.; Guin, J.

    2005-12-01

    Probabilistic earthquake hazard and loss analyses play important roles in many areas of risk management, including earthquake related public policy and insurance ratemaking. Rigorous loss estimation for portfolios of properties is difficult since there are various types of uncertainties in all aspects of modeling and analysis. It is the objective of this study to investigate the sensitivity of earthquake loss estimation to uncertainties in regional seismicity, earthquake source parameters, ground motions, and sites' spatial correlation on typical property portfolios in Southern California. Southern California is an attractive region for such a study because it has a large population concentration exposed to significant levels of seismic hazard. During the last decade, there have been several comprehensive studies of most regional faults and seismogenic sources. There have also been detailed studies on regional ground motion attenuations and regional and local site responses to ground motions. This information has been used by engineering seismologists to conduct regional seismic hazard and risk analysis on a routine basis. However, one of the more difficult tasks in such studies is the proper incorporation of uncertainties in the analysis. From the hazard side, there are uncertainties in the magnitudes, rates and mechanisms of the seismic sources and local site conditions and ground motion site amplifications. From the vulnerability side, there are considerable uncertainties in estimating the state of damage of buildings under different earthquake ground motions. From an analytical side, there are challenges in capturing the spatial correlation of ground motions and building damage, and integrating thousands of loss distribution curves with different degrees of correlation. In this paper we propose to address some of these issues by conducting loss analyses of a typical small portfolio in southern California, taking into consideration various source and ground

  17. Earthquake Facts

    Science.gov (United States)

    ... North Dakota, and Wisconsin. The core of the earth was the first internal structural element to be identified. In 1906 R.D. Oldham discovered it from his studies of earthquake records. The inner core is solid, and the outer core is liquid and so does not transmit ...

  18. Psychological distress among Bam earthquake survivors in Iran: a population-based study

    Directory of Open Access Journals (Sweden)

    Garmaroudi Gholamreza

    2005-01-01

    Full Text Available Abstract Background An earthquake measuring 6.3 on the Richter scale struck the city of Bam in Iran on the 26th of December 2003 at 5.26 A.M. It was devastating, and left over 40,000 dead and around 30,000 injured. The profound tragedy of thousands killed has caused emotional and psychological trauma for tens of thousands of people who have survived. A study was carried out to assess psychological distress among Bam earthquake survivors and factors associated with severe mental health in those who survived the tragedy. Methods This was a population-based study measuring psychological distress among the survivors of Bam earthquake in Iran. Using a multi-stage stratified sampling method a random sample of individuals aged 15 years and over living in Bam were interviewed. Psychological distress was measured using the 12-item General Health Questionnaire (GHQ-12. Results In all 916 survivors were interviewed. The mean age of the respondents was 32.9 years (SD = 12.4, mostly were males (53%, married (66% and had secondary school education (50%. Forty-one percent reported they lost 3 to 5 members of their family in the earthquake. In addition the findings showed that 58% of the respondents suffered from severe mental health as measured by the GHQ-12 and this was three times higher than reported psychological distress among the general population. There were significant differences between sub-groups of the study sample with regard to their psychological distress. The results of the logistic regression analysis also indicated that female gender; lower education, unemployment, and loss of family members were associated with severe psychological distress among earthquake victims. Conclusion The study findings indicated that the amount of psychological distress among earthquake survivors was high and there is an urgent need to deliver mental health care to disaster victims in local medical settings and to reduce negative health impacts of the earthquake

  19. Method to deterministically study photonic nanostructures in different experimental instruments

    NARCIS (Netherlands)

    Husken, B.H.; Woldering, L.A.; Blum, Christian; Tjerkstra, R.W.; Vos, Willem L.

    2009-01-01

    We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the

  20. Seismic Hazard characterization study using an earthquake source with Probabilistic Seismic Hazard Analysis (PSHA) method in the Northern of Sumatra

    International Nuclear Information System (INIS)

    Yahya, A.; Palupi, M. I. R.; Suharsono

    2016-01-01

    Sumatra region is one of the earthquake-prone areas in Indonesia because it is lie on an active tectonic zone. In 2004 there is earthquake with a moment magnitude of 9.2 located on the coast with the distance 160 km in the west of Nanggroe Aceh Darussalam and triggering a tsunami. These events take a lot of casualties and material losses, especially in the Province of Nanggroe Aceh Darussalam and North Sumatra. To minimize the impact of the earthquake disaster, a fundamental assessment of the earthquake hazard in the region is needed. Stages of research include the study of literature, collection and processing of seismic data, seismic source characterization and analysis of earthquake hazard by probabilistic methods (PSHA) used earthquake catalog from 1907 through 2014. The earthquake hazard represented by the value of Peak Ground Acceleration (PGA) and Spectral Acceleration (SA) in the period of 0.2 and 1 second on bedrock that is presented in the form of a map with a return period of 2475 years and the earthquake hazard curves for the city of Medan and Banda Aceh. (paper)

  1. Earthquakes in El Salvador: a descriptive study of health concerns in a rural community and the clinical implications, part I.

    Science.gov (United States)

    Woersching, Joanna C; Snyder, Audrey E

    2003-01-01

    This is the first article in a series that evaluates the health concerns of people living in a Salvadoran rural community after major earthquakes. Part I reviews the background, methods, and results of post-earthquake conditions with regards to healthcare, access to healthcare, housing, food, water and sanitation. Part II reviews the implications of these results and recommendations for improvements within the community. Part III investigates the psychosocial and mental health consequences of the earthquakes and provides suggestions for improved mental health awareness, assessment, and intervention. El Salvador experienced 2 major earthquakes in January and February 2001. This study evaluates the effects of the earthquakes on the health practices in the rural town of San Sebastian. The research was conducted with use of a convenience sample survey of subjects affected by the earthquakes. The sample included 594 people within 100 households. The 32-question survey assessed post-earthquake conditions in the areas of health care and access to care, housing, food and water, and sanitation. Communicable diseases affected a number of family members. After the earthquakes, 38% of households reported new injuries, and 79% reported acute exacerbations of chronic illness. Rural inhabitants were 30% more likely to have an uninhabitable home than were urban inhabitants. Concerns included safe housing, water purification, and waste elimination. The findings indicate a need for greater public health awareness and community action to adapt living conditions after a disaster and prevent the spread of communicable disease.

  2. Facilitators and obstacles in pre-hospital medical response to earthquakes: a qualitative study

    Science.gov (United States)

    2011-01-01

    Background Earthquakes are renowned as being amongst the most dangerous and destructive types of natural disasters. Iran, a developing country in Asia, is prone to earthquakes and is ranked as one of the most vulnerable countries in the world in this respect. The medical response in disasters is accompanied by managerial, logistic, technical, and medical challenges being also the case in the Bam earthquake in Iran. Our objective was to explore the medical response to the Bam earthquake with specific emphasis on pre-hospital medical management during the first days. Methods The study was performed in 2008; an interview based qualitative study using content analysis. We conducted nineteen interviews with experts and managers responsible for responding to the Bam earthquake, including pre-hospital emergency medical services, the Red Crescent, and Universities of Medical Sciences. The selection of participants was determined by using a purposeful sampling method. Sample size was given by data saturation. Results The pre-hospital medical service was divided into three categories; triage, emergency medical care and transportation, each category in turn was identified into facilitators and obstacles. The obstacles identified were absence of a structured disaster plan, absence of standardized medical teams, and shortage of resources. The army and skilled medical volunteers were identified as facilitators. Conclusions The most compelling, and at the same time amenable obstacle, was the lack of a disaster management plan. It was evident that implementing a comprehensive plan would not only save lives but decrease suffering and enable an effective praxis of the available resources at pre-hospital and hospital levels. PMID:21575233

  3. Facilitators and obstacles in pre-hospital medical response to earthquakes: a qualitative study.

    Science.gov (United States)

    Djalali, Ahmadreza; Khankeh, Hamidreza; Öhlén, Gunnar; Castrén, Maaret; Kurland, Lisa

    2011-05-16

    Earthquakes are renowned as being amongst the most dangerous and destructive types of natural disasters. Iran, a developing country in Asia, is prone to earthquakes and is ranked as one of the most vulnerable countries in the world in this respect. The medical response in disasters is accompanied by managerial, logistic, technical, and medical challenges being also the case in the Bam earthquake in Iran. Our objective was to explore the medical response to the Bam earthquake with specific emphasis on pre-hospital medical management during the first days. The study was performed in 2008; an interview based qualitative study using content analysis. We conducted nineteen interviews with experts and managers responsible for responding to the Bam earthquake, including pre-hospital emergency medical services, the Red Crescent, and Universities of Medical Sciences. The selection of participants was determined by using a purposeful sampling method. Sample size was given by data saturation. The pre-hospital medical service was divided into three categories; triage, emergency medical care and transportation, each category in turn was identified into facilitators and obstacles. The obstacles identified were absence of a structured disaster plan, absence of standardized medical teams, and shortage of resources. The army and skilled medical volunteers were identified as facilitators. The most compelling, and at the same time amenable obstacle, was the lack of a disaster management plan. It was evident that implementing a comprehensive plan would not only save lives but decrease suffering and enable an effective praxis of the available resources at pre-hospital and hospital levels.

  4. Recent Achievements of the Collaboratory for the Study of Earthquake Predictability

    Science.gov (United States)

    Jackson, D. D.; Liukis, M.; Werner, M. J.; Schorlemmer, D.; Yu, J.; Maechling, P. J.; Zechar, J. D.; Jordan, T. H.

    2015-12-01

    Maria Liukis, SCEC, USC; Maximilian Werner, University of Bristol; Danijel Schorlemmer, GFZ Potsdam; John Yu, SCEC, USC; Philip Maechling, SCEC, USC; Jeremy Zechar, Swiss Seismological Service, ETH; Thomas H. Jordan, SCEC, USC, and the CSEP Working Group The Collaboratory for the Study of Earthquake Predictability (CSEP) supports a global program to conduct prospective earthquake forecasting experiments. CSEP testing centers are now operational in California, New Zealand, Japan, China, and Europe with 435 models under evaluation. The California testing center, operated by SCEC, has been operational since Sept 1, 2007, and currently hosts 30-minute, 1-day, 3-month, 1-year and 5-year forecasts, both alarm-based and probabilistic, for California, the Western Pacific, and worldwide. We have reduced testing latency, implemented prototype evaluation of M8 forecasts, and are currently developing formats and procedures to evaluate externally-hosted forecasts and predictions. These efforts are related to CSEP support of the USGS program in operational earthquake forecasting and a DHS project to register and test external forecast procedures from experts outside seismology. A retrospective experiment for the 2010-2012 Canterbury earthquake sequence has been completed, and the results indicate that some physics-based and hybrid models outperform purely statistical (e.g., ETAS) models. The experiment also demonstrates the power of the CSEP cyberinfrastructure for retrospective testing. Our current development includes evaluation strategies that increase computational efficiency for high-resolution global experiments, such as the evaluation of the Global Earthquake Activity Rate (GEAR) model. We describe the open-source CSEP software that is available to researchers as they develop their forecast models (http://northridge.usc.edu/trac/csep/wiki/MiniCSEP). We also discuss applications of CSEP infrastructure to geodetic transient detection and how CSEP procedures are being

  5. Fear based Education or Curiosity based Education as an Example of Earthquake and Natural Disaster Education: Results of Statistical Study in Primary Schools in Istanbul-Turkey

    Science.gov (United States)

    Ozcep, T.; Ozcep, F.

    2012-04-01

    Natural disaster reduction focuses on the urgent need for prevention activities to reduce loss of life, damage to property, infrastructure and environment, and the social and economic disruption caused by natural hazards. One of the most important factors in reduction of the potential damage of earthquakes is trained manpower. To understanding the causes of earthquakes and other natural phenomena (landslides, avalanches, floods, volcanoes, etc.) is one of the pre-conditions to show a conscious behavior. The aim of the study is to analysis and to investigate, how earthquakes and other natural phenomena are perceived by the students and the possible consequences of this perception, and their effects of reducing earthquake damage. One of the crucial questions is that is our education system fear or curiosity based education system? Effects of the damages due to earthquakes have led to look like a fear subject. In fact, due to the results of the effects, the earthquakes are perceived scary phenomena. In the first stage of the project, the learning (or perception) levels of earthquakes and other natural disasters for the students of primary school are investigated with a survey. Aim of this survey study of earthquakes and other natural phenomena is that have the students fear based or curiosity based approaching to the earthquakes and other natural events. In the second stage of the project, the path obtained by the survey are evaluated with the statistical point of approach. A questionnaire associated with earthquakes and natural disasters are applied to primary school students (that total number of them is approximately 700 pupils) to measure the curiosity and/or fear levels. The questionnaire consists of 17 questions related to natural disasters. The questions are: "What is the Earthquake ?", "What is power behind earthquake?", "What is the mental response during the earthquake ?", "Did we take lesson from earthquake's results ?", "Are you afraid of earthquake

  6. Shortcomings of InSAR for studying megathrust earthquakes: The case of the M w 9.0 Tohoku-Oki earthquake

    KAUST Repository

    Feng, Guangcai

    2012-05-28

    Interferometric Synthetic Aperture Radar (InSAR) observations are sometimes the only geodetic data of large subduction-zone earthquakes. However, these data usually suffer from spatially long-wavelength orbital and atmospheric errors that can be difficult to distinguish from the coseismic deformation and may therefore result in biased fault-slip inversions. To study how well InSAR constrains fault-slip of large subduction zone earthquakes, we use data of the 11 March 2011 Tohoku-Oki earthquake (Mw9.0) and test InSAR-derived fault-slip models against models constrained by GPS data from the extensive nationwide network in Japan. The coseismic deformation field was mapped using InSAR data acquired from multiple ascending and descending passes of the ALOS and Envisat satellites. We then estimated several fault-slip distribution models that were constrained using the InSAR data alone, onland and seafloor GPS/acoustic data, or combinations of the different data sets. Based on comparisons of the slip models, we find that there is no real gain by including InSAR observations for determining the fault slip distribution of this earthquake. That said, however, some of the main fault-slip patterns can be retrieved using the InSAR data alone when estimating long wavelength orbital/atmospheric ramps as a part of the modeling. Our final preferred fault-slip solution of the Tohoku-Oki earthquake is based only on the GPS data and has maximum reverse- and strike-slip of 36.0 m and 6.0 m, respectively, located northeast of the epicenter at a depth of 6 km, and has a total geodetic moment is 3.6 × 1022 Nm (Mw 9.01), similar to seismological estimates.

  7. Instrumental neutron activation analysis in environmental studies of trace elements

    International Nuclear Information System (INIS)

    Salmon, L.

    1975-06-01

    The application of a routine instrumental nuclear method is described in relation to environmental surveys and studies. A working rather than formal review is made of the techniques applied with particular reference to the data processing methods involved. The elements measured by instrumental activation analysis were: Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Cd, Co, Cr, Cs, Cu, Fe, Hg, I, In, La, Mn, Na, Ni, Pb, Rb, Sb, Sc, Se, Th, Ti, U, V, W, Zn. (author)

  8. Developing a new perspective to study the health of survivors of Sichuan earthquakes in China: a study on the effect of post-earthquake rescue policies on survivors' health-related quality of life.

    Science.gov (United States)

    Liang, Ying; Wang, Xiukun

    2013-10-29

    Sichuan is a province in China with an extensive history of earthquakes. Recent earthquakes, including the Lushan earthquake in 2013, have resulted in thousands of people losing their homes and their families. However, there is a research gap on the efficiency of government support policies. Therefore, this study develops a new perspective to study the health of earthquake survivors, based on the effect of post-earthquake rescue policies on health-related quality of life (HRQOL) of survivors of the Sichuan earthquake. This study uses data from a survey conducted in five hard-hit counties (Wenchuan, Qingchuan, Mianzhu, Lushan, and Dujiangyan) in Sichuan in 2013. A total of 2,000 questionnaires were distributed, and 1,672 were returned; the response rate was 83.6%. Results of the rescue policies scale and Medical Outcomes Study Short Form 36 (SF-36) scale passed the reliability test. The confirmatory factor analysis model showed that the physical component summary (PCS) directly affected the mental component summary (MCS). The results of structural equation model regarding the effects of rescue policies on HRQOL showed that the path coefficients of six policies (education, orphans, employment, poverty, legal, and social rescue policies) to the PCS of survivors were all positive and passed the test of significance. Finally, although only the path coefficient of the educational rescue policy to the MCS of survivors was positive and passed the test of significance, the other five policies affected the MCS indirectly through the PCS. The general HRQOL of survivors is not ideal; the survivors showed a low satisfaction with the post-earthquake rescue policies. Further, the six post-earthquake rescue policies significantly improved the HRQOL of survivors and directly affected the promotion of the PCS of survivors. Aside from the educational rescue policy, all other policies affected the MCS indirectly through the PCS. This finding indicates relatively large differences in

  9. The impact of the Great East Japan earthquake on mandatory psychiatric emergency hospitalizations in Tokyo: a retrospective observational study.

    Science.gov (United States)

    Aoki, A; Aoki, Y; Harima, H

    2012-10-09

    On 11 March 2011, the eastern part of Japan was struck by a magnitude 9.0 quake. About 20 000 people were killed or were missing, and a nuclear crisis followed. In Tokyo, people were indirectly exposed to the earthquake and nuclear crisis by TV broadcast. The aim of our study was to evaluate the potential effect of the series of catastrophes on psychiatric emergency hospitalizations in Tokyo. Clinical records of patients who were mandatorily admitted to Tokyo Metropolitan Matsuzawa Hospital by law because of urgent risk to self or others were reviewed. Records regarding the 2 years of investigation, which include the 6 months after the earthquake, were reviewed. The six months after the earthquake were compared with the eighteen months before the earthquake in clinical and demographic data using independent t-tests or χ(2) tests. During the 6 months before and after the earthquake, 97 and 127 people were mandatorily admitted. χ(2) Tests demonstrated a significant increase in the number of patients after the earthquake (P = 0.045), attributable to the significant increase in the number of patients with schizophrenia after the earthquake (P = 0.011, 32 vs 56), whereas there were no significant differences in the number of patients with other diagnoses between those two periods. Independent t-tests revealed that patients admitted after the earthquake had marginally significantly shorter periods of education compared with those admitted before the earthquake (13.78 vs 12.82 years, P = 0.084). This work suggests that patients with schizophrenia were more sensitive to indirect exposure to the earthquake and that a shorter period of education was a potential risk factor.

  10. The Southern California Earthquake Center/Undergraduate Studies in Earthquake Information Technology (SCEC/UseIT) Internship Program

    Science.gov (United States)

    Perry, S.; Jordan, T.

    2006-12-01

    Our undergraduate research program, SCEC/UseIT, an NSF Research Experience for Undergraduates site, provides software for earthquake researchers and educators, movies for outreach, and ways to strengthen the technical career pipeline. SCEC/UseIT motivates diverse undergraduates towards science and engineering careers through team-based research in the exciting field of earthquake information technology. UseIT provides the cross-training in computer science/information technology (CS/IT) and geoscience needed to make fundamental progress in earthquake system science. Our high and increasing participation of women and minority students is crucial given the nation"s precipitous enrollment declines in CS/IT undergraduate degree programs, especially among women. UseIT also casts a "wider, farther" recruitment net that targets scholars interested in creative work but not traditionally attracted to summer science internships. Since 2002, SCEC/UseIT has challenged 79 students in three dozen majors from as many schools with difficult, real-world problems that require collaborative, interdisciplinary solutions. Interns design and engineer open-source software, creating increasingly sophisticated visualization tools (see "SCEC-VDO," session IN11), which are employed by SCEC researchers, in new curricula at the University of Southern California, and by outreach specialists who make animated movies for the public and the media. SCEC-VDO would be a valuable tool for research-oriented professional development programs.

  11. Instrumental shaking thresholds for seismically induced landslides and preliminary report on landslides triggered by the October 17, 1989, Loma Prieta, California earthquake

    Science.gov (United States)

    Harp, E.L.

    1993-01-01

    The generation of seismically induced landslide depends on the characteristics of shaking as well as mechanical properties of geologic materials. A very important parameter in the study of seismically induced landslide is the intensity based on a strong-motion accelerogram: it is defined as Arias intensity and is proportional to the duration of the shaking record as well as the amplitude. Having a theoretical relationship between Arias intensity, magnitude and distance it is possible to predict how far away from the seismic source landslides are likely to occur for a given magnitude earthquake. Field investigations have established that the threshold level of Arias intensity depends also on site effects, particularly the fracture characteristics of the outcrops present. -from Author

  12. Original earthquake design basis in light of recent seismic hazard studies

    International Nuclear Information System (INIS)

    Petrovski, D.

    1993-01-01

    For the purpose of conceiving the framework within which efforts have been made in the eastern countries to construct earthquake resistant nuclear power plants, a review of the development and application of the seismic zoning map of USSR is given. The normative values of seismic intensity and acceleration are discussed from the aspect of recent probabilistic seismic hazard studies. To that effect, presented briefly in this paper is the methodology of probabilistic seismic hazard analysis. (author)

  13. Numerical simulation of multiple-physical fields coupling for thermal anomalies before earthquakes: A case study of the 2008 Wenchuan Ms8.0 earthquake in southwest China

    Science.gov (United States)

    Deng, Z.

    2017-12-01

    It has become a highly focused issue that thermal anomalies appear before major earthquakes. There are various hypotheses about the mechanism of thermal anomalies. Because of lacking of enough evidences, the mechanism is still require to be further researched. Gestation and occurrence of a major earthquake is related with the interaction of multi-physical fields. The underground fluid surging out the surface is very likely to be the reason for the thermal anomaly. This study tries to answer some question, such as how the geothermal energy transfer to the surface, and how the multiple-physical fields interacted. The 2008 Wenchuan Ms8.0 earthquake, is one of the largest evens in the last decade in China mainland. Remote sensing studies indicate that distinguishable thermal anomalies occurred several days before the earthquake. The heat anomaly value is more than 3 times the average in normal time and distributes along the Longmen Shan fault zone. Based on geological and geophysical data, 2D dynamic model of coupled stress, seepage and thermal fields (HTM model) is constructed. Then using the COMSOL multi-physics filed software, this work tries to reveal the generation process and distribution patterns of thermal anomalies prior to thrust-type major earthquakes. The simulation get the results: (1)Before the micro rupture, with the increase of compression, the heat current flows to the fault in the footwall on the whole, while in the hanging wall of the fault, particularly near the ground surface, the heat flow upward. In the fault zone, heat flow upward along the fracture surface, heat flux in the fracture zone is slightly larger than the wall rock;, but the value is all very small. (2)After the occurrence of the micro fracture, the heat flow rapidly collects to the faults. In the fault zones, the heat flow accelerates up along the fracture surfaces, the heat flux increases suddenly, and the vertical heat flux reaches to the maximum. The heat flux in the 3 fracture

  14. Study on business resilience factors toward earthquake and tsunami - A case study of Padang city

    Science.gov (United States)

    Rahayu, Harkunti P.; Aini, Qurrata; Putri, Amalia Novianti

    2017-07-01

    As as the Capital of West Sumatera Province and as the largest city at the West Coast of Sumatera, the City of Padang has been assigned as one of the National Activity Center for Regional Economic Development. The city will be developed as a metropolitan city, which will be very much relied on the multi sectoral support such as business, services, industry, and tourism sectors. However, the city is located at a very high-risk zone for earthquake and tsunami. After 2004 Indian Ocean Tsunami, the city has been stricken several times by large earthquake and tsunami threat, for example in 8.4 M September 2007 and 7.6 M September 2009 causing major casualties, severe damages, great economic loss as well as tsunami threat to the people. Without disaster risk reduction based development planning, the goal of Padang as metropolitan and National Activity Center is difficult to be achieved. Knowing the level of risk and its appropriate countermeasures from the perspective of business resilience becomes very important. Thus, this paper will present the detail study on business reliency for the Padang City, starting from (i) Earthquake and Tsunami Risk Assessment from the perspective of preparedness for Business in Padang Barat Subdistrict of Padang City, (ii) Assessment of resiliency level of Padang City Business after the 2009 event, and (iii) recommendation for considering the Business Resilience factors as part of DRR based CBD development Plan of Padang Barat sub district - Padang City. This study is not only able to identify physical and nonphusical aspect of business characteristic, but it has identified four major components of Bussiness Resiliency Indicators, i.e. Swift Recovery Factors (RR), Experience and Knowledge to Disaster (PP), Emergency Response Plan (RT) and Asset Protection (PA). Each major indicator consists of several indicators, with 19 total indicators. Further investigation on these indicators shown that total performance value of business resiliency is

  15. Crustal structure and Seismic Hazard studies in Nigeria from ambient noise and earthquakes

    Science.gov (United States)

    Kadiri, U. A.

    2016-12-01

    The crust, upper Mantle and seismic hazard studies have been carried out in Nigeria using noise and earthquake data. The data were acquired from stations in Nigeria and international Agencies. Firstly, known depths of sediments in the Lower Benue Trough (LBT) were collected from wells; Resonance frequency (Fo) and average shear-wave velocities (Vs) were then computed using Matlab. Secondly, average velocities were estimated from noise cross-correlation along seismic stations. Thirdly, the moho depths beneath Ife, Kaduna and Nsukka stations were estimated, as well as Vp/Vs ratio using 2009 earthquake with epicenter in Nigeria. Finally, Statistical and Probabilistic Seismic Hazard Assessment (PSHA) were used to compute seismic hazard parameters in Nigeria and its surroundings. The results showed that, soils on the LBT with average shear wave velocity of about 5684m/s would experience more amplification in case of an earthquake, compared to the basement complex in Nigeria. The Vs beneath the seismic stations in Nigeria were also estimated as 288m/s, 1019m/s, 940.6m/s and 255.02m/s in Ife, Nsukka, Awka, and Abakaliki respectively. The average velocity along the station paths was 4.5km/secs, and the Vp, Vs for depths 100-500km profile in parts of South West Nigeria increased from about 5.83-6.42Km/sec and 3.48-6.31km/s respectively with Vp/Vs ratio decreasing from 1.68 to 1.02. Statistical analysis revealed a trend of increasing earthquake occurrence along the Mid-Atlantic Ridge and tending to West African region. The analysis of PSHA shows the likelihood of earthquakes with different magnitudes occurring in Nigeria and other parts West Africa in future. This work is aimed at addressing critical issues regarding sites effect characterization, improved earthquake location and robust seismic hazards assessment for planning in the choice of sites for critical facilities in Nigeria. Keywords: Sediment thickness, Resonance Frequency, Average Velocity, Seismic Hazard, Nigeria

  16. Geoethics and decision science issues in Japan's disaster management system: case study in the 2011 Tohoku earthquake and tsunami

    Science.gov (United States)

    Sugimoto, Megumi

    2015-04-01

    The March 11, 2011 Tohoku earthquake and its tsunami killed 18,508 people, including the missing (National Police Agency report as of April 2014) and raise the Level 7 accident at TEPCO's Fukushima Dai-ichi nuclear power station in Japan. The problems revealed can be viewed as due to a combination of risk-management, risk-communication, and geoethics issues. Japan's preparations for earthquakes and tsunamis are based on the magnitude of the anticipated earthquake for each region. The government organization coordinating the estimation of anticipated earthquakes is the "Headquarters for Earthquake Research Promotion" (HERP), which is under the Ministry of Education, Culture, Sports, Science and Technology (MEXT). Japan's disaster mitigation system is depicted schematically as consisting of three layers: seismology, civil engineering, and disaster mitigation planning. This research explains students in geoscience should study geoethics as part of their education related Tohoku earthquake and the Level 7 accident at TEPCO's Fukushima Dai-ichi nuclear power station. Only when they become practicing professionals, they will be faced with real geoethical dilemmas. A crisis such as the 2011 earthquake, tsunami, and Fukushima Dai-ichi nuclear accident, will force many geoscientists to suddenly confront previously unanticipated geoethics and risk-communication issues. One hopes that previous training will help them to make appropriate decisions under stress. We name it "decision science".

  17. Study on evaluating method for earthquake resisting performance of steel piers; Kosei kyokyaku no taishinsei ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Isoe, A.; Hashimoto, Y.; Morimoto, C.; Sakoda, H.; Ishige, T.; Yoshikawa, T.; Kishida, K. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1998-12-20

    After the shock of Hyogoken Nanbu Earthquake in 1995, protection against level 2 earthquake becomes important subject for civil structures. Subsequently plastic design methods for steel piers have been studied and rapidly introduced. The authors developed a method to evaluate the earthquake resisting performance of a steel pier with a single mass model. This model is useful for design because of its simplicity but on the other hand it can not consider the effects of piers` interaction in space. To include this effect in an analysis a simple 3 dimensional calculation model of box-column pier is developed. (author)

  18. Trends of Serum Electrolyte Changes in Crush syndrome patients of Bam Earthquake; a Cross sectional Study

    Directory of Open Access Journals (Sweden)

    Saeed Safari

    2016-12-01

    Full Text Available Introduction: Electrolyte imbalances are very common among crushed earthquake victims but there is notenough data regarding their trend of changes. The present study was designed to evaluate the trend of changesin sodium, calcium, and phosphorus ions among crush syndrome patients. Methods: In this retrospectivecross-sectional study, using the database of Bam earthquake victims, which was developed by Iranian Society ofNephrology following Bam earthquake, Iran, 2003, the 10-day trend of sodium, calcium, and phosphorus ionschanges in > 15 years old crush syndrome patients was evaluated. Results: 118 patients with the mean age of25.6 § 6.9 yearswere studied (57.3 male. On the first day of admission, 52.5% (95% CI: 42.7 - 62.3 of the patientshad hyponatremia, which reached 43.9% (95% CI: 28.5 - 59.3 on day 10. 100.0% of patients were hypocalcemicon admission and serum calcium level did not change dramatically during the 10 days of hospitalization. Theprevalence of hyperphosphatemia on the first day was 90.5% (95% CI: 81.5 - 99.5 and on the 10th day of hospitalization66.7% (95% CI: 48.5 - 84.8 of the patients were still affected. Conclusion: The results of the presentstudy shows the 52.5%prevalence of hyponatremia, 100% hypocalcemia, and 90.5% hyperphosphatemia amongcrush syndrome patients of Bam earthquake victims on the first day of admission. Evaluation of 10-day trendshows a slow decreasing pattern of these imbalances as after 10 days, 43.9% still remain hyponatremic, 92.3%hypocalcemic, and 66.7% hypophosphatemic.

  19. Resilience of aging populations after devastating earthquake event and its determinants - A case study of the Chi-Chi earthquake in Taiwan

    Science.gov (United States)

    Hung, Chih-Hsuan; Hung, Hung-Chih

    2016-04-01

    1.Background Major portions of urban areas in Asia are highly exposed and vulnerable to devastating earthquakes. Many studies identify ways to reduce earthquake risk by concentrating more on building resilience for the particularly vulnerable populations. By 2020, as the United Nations' warning, many Asian countries would become 'super-aged societies', such as Taiwan. However, local authorities rarely use resilience approach to frame earthquake disaster risk management and land use strategies. The empirically-based research about the resilience of aging populations has also received relatively little attention. Thus, a challenge arisen for decision-makers is how to enhance resilience of aging populations within the context of risk reduction. This study aims to improve the understanding of the resilience of aging populations and its changes over time in the aftermath of a destructive earthquake at the local level. A novel methodology is proposed to assess the resilience of aging populations and to characterize their changes of spatial distribution patterns, as well as to examine their determinants. 2.Methods and data An indicator-based assessment framework is constructed with the goal of identifying composite indicators (including before, during and after a disaster) that could serve as proxies for attributes of the resilience of aging populations. Using the recovery process of the Chi-Chi earthquake struck central Taiwan in 1999 as a case study, we applied a method combined a geographical information system (GIS)-based spatial statistics technique and cluster analysis to test the extent of which the resilience of aging populations is spatially autocorrelated throughout the central Taiwan, and to explain why clustering of resilient areas occurs in specific locations. Furthermore, to scrutinize the affecting factors of resilience, we develop an aging population resilience model (APRM) based on existing resilience theory. Using the APRM, we applied a multivariate

  20. Radon, gas geochemistry, groundwater, and earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    King, Chi-Yu [Power Reactor and Nuclear Fuel Development Corp., Tono Geoscience Center, Toki, Gifu (Japan)

    1998-12-31

    Radon monitoring in groundwater, soil air, and atmosphere has been continued in many seismic areas of the world for earthquake-prediction and active-fault studies. Some recent measurements of radon and other geochemical and hydrological parameters have been made for sufficiently long periods, with reliable instruments, and together with measurements of meteorological variables and solid-earth tides. The resultant data are useful in better distinguishing earthquake-related changes from various background noises. Some measurements have been carried out in areas where other geophysical measurements are being made also. Comparative studies of various kinds of geophysical data are helpful in ascertaining the reality of the earthquake-related and fault-related anomalies and in understanding the underlying mechanisms. Spatial anomalies of radon and other terrestrial gasses have been observed for many active faults. Such observations indicate that gas concentrations are very much site dependent, particularly on fault zones where terrestrial fluids may move vertically. Temporal anomalies have been reliably observed before and after some recent earthquakes, including the 1995 Kobe earthquake, and the general pattern of anomaly occurrence remains the same as observed before: They are recorded at only relatively few sensitive sites, which can be at much larger distances than expected from existing earthquake-source models. The sensitivity of a sensitive site is also found to be changeable with time. These results clearly show the inadequacy of the existing dilatancy-fluid diffusion and elastic-dislocation models for earthquake sources to explain earthquake-related geochemical and geophysical changes recorded at large distances. (J.P.N.)

  1. Implications of ground water chemistry and flow patterns for earthquake studies.

    Science.gov (United States)

    Guangcai, Wang; Zuochen, Zhang; Min, Wang; Cravotta, Charles A; Chenglong, Liu

    2005-01-01

    Ground water can facilitate earthquake development and respond physically and chemically to tectonism. Thus, an understanding of ground water circulation in seismically active regions is important for earthquake prediction. To investigate the roles of ground water in the development and prediction of earthquakes, geological and hydrogeological monitoring was conducted in a seismogenic area in the Yanhuai Basin, China. This study used isotopic and hydrogeochemical methods to characterize ground water samples from six hot springs and two cold springs. The hydrochemical data and associated geological and geophysical data were used to identify possible relations between ground water circulation and seismically active structural features. The data for delta18O, deltaD, tritium, and 14C indicate ground water from hot springs is of meteoric origin with subsurface residence times of 50 to 30,320 years. The reservoir temperature and circulation depths of the hot ground water are 57 degrees C to 160 degrees C and 1600 to 5000 m, respectively, as estimated by quartz and chalcedony geothermometers and the geothermal gradient. Various possible origins of noble gases dissolved in the ground water also were evaluated, indicating mantle and deep crust sources consistent with tectonically active segments. A hard intercalated stratum, where small to moderate earthquakes frequently originate, is present between a deep (10 to 20 km), high-electrical conductivity layer and the zone of active ground water circulation. The ground water anomalies are closely related to the structural peculiarity of each monitoring point. These results could have implications for ground water and seismic studies in other seismogenic areas.

  2. Impact of 2015 earthquakes on a local hospital in Nepal: A prospective hospital-based study.

    Science.gov (United States)

    Giri, Samita; Risnes, Kari; Uleberg, Oddvar; Rogne, Tormod; Shrestha, Sanu Krishna; Nygaard, Øystein Petter; Koju, Rajendra; Solligård, Erik

    2018-01-01

    Natural disasters pose a great challenge to the health systems and individual health facilities. In low-resource settings, disaster preparedness systems are often limited and not been well described. Two devastating earthquakes hit Nepal within a 17-days period in 2015. This study aims to describe the burden and distribution of emergency cases to a local hospital. This is a prospective observational study of patients presenting to a local hospital for a period of 21 days following the earthquake on April 25, 2015. Demographic and clinical information was prospectively registered for all patients in the systematic emergency registry. Systematic telephone interviews were conducted in a random sample of the patients 90 days after admission to the hospital. A total of 2,003 emergency patients were registered during the period. The average daily number of emergency patients during the first five days was almost five times higher (n = 150) than the pre-incident daily average (n = 35). The majority of injuries were fractures (58%), 348 (56%) in the lower extremities. A total of 345 surgical procedures were performed and the hospital treated 111 patients with severe injuries related to the earthquake (compartment syndrome, crush injury, and internal injury). Among those with follow-up interviews, over 90% reported that they had been severely affected by the earthquakes; complete house damage, living in temporary shelter, or loss of close family member. The hospital experienced a very high caseload during the first days, and the majority of patients needed orthopaedic services. The proportion of severely injured and in-hospital deaths were relatively low, probably indicating that the most severely injured did not reach the hospital in time. The experiences underline the need for robust and easily available local health services that can respond to disasters.

  3. A comparative study on strengthening applications of prefabricated buildings in earthquake regions

    International Nuclear Information System (INIS)

    Arslan, M. Hakan; Gulay, F. Gulten

    2006-01-01

    Damages to prefabricated industrial structures caused by earthquakes in the last ten years in Turkey have occurred to an enormous extent. Among the causes of this damage, the inherent characteristic weakness of the load-carrying systems and constructing most of them according to the earthquake code applied before 1998 can be listed. The tragic situation that appeared after earthquakes emphasized that existing prefabricated constructions should be strengthened/improved according to the code which became valid after 1998. This study comprises three sections. The damage types in prefabricated reinforced concrete structures caused by earthquakes and the strengthening models (samples) that can be applied to these structures will be mentioned in the first and second sections, respectively. The last and the analytical part of the study will be about the selection of the most often damaged industrial construction type which is preferred in industrial regions and application of selecting strengthening methods performed by modeling these structures according to three different span types (1-S, 2-S, 3-S). The strengthening methods will be Sheer wall (SW), Steel Bracing (B), Steel Beam (SB) and Column Jacketing (CJ). All the systems will be calculated by using non-linear procedures (pushover analysis). The analysis performed by using a Software Package (DRAIN-2DX), will be applied to each frame in order to obtain load-displacement curves. The real hinge parameters will be defined using FEMA-356 to reflect the existing conditions. The results will be compared by considering the contribution of strengthening and especially system performance to displacement ductility. (author)

  4. Experimental Study of Thermal Field Evolution in the Short-Impending Stage Before Earthquakes

    Science.gov (United States)

    Ren, Yaqiong; Ma, Jin; Liu, Peixun; Chen, Shunyun

    2017-08-01

    Phenomena at critical points are vital for identifying the short-impending stage prior to earthquakes. The peak stress is a critical point when stress is converted from predominantly accumulation to predominantly release. We call the duration between the peak stress and instability "the meta-instability stage", which refers to the short-impending stage of earthquakes. The meta-instability stage consists of a steady releasing quasi-static stage and an accelerated releasing quasi-dynamic stage. The turning point of the above two stages is the remaining critical point. To identify the two critical points in the field, it is necessary to study the characteristic phenomena of various physical fields in the meta-instability stage in the laboratory, and the strain and displacement variations were studied. Considering that stress and relative displacement can be detected by thermal variations and peculiarities in the full-field observations, we employed a cooled thermal infrared imaging system to record thermal variations in the meta-instability stage of stick slip events generated along a simulated, precut planer strike slip fault in a granodiorite block on a horizontally bilateral servo-controlled press machine. The experimental results demonstrate the following: (1) a large area of decreasing temperatures in wall rocks and increasing temperatures in sporadic sections of the fault indicate entrance into the meta-instability stage. (2) The rapid expansion of regions of increasing temperatures on the fault and the enhancement of temperature increase amplitude correspond to the turning point from the quasi-static stage to the quasi-dynamic stage. Our results reveal thermal indicators for the critical points prior to earthquakes that provide clues for identifying the short-impending stage of earthquakes.

  5. Review of Van earthquakes form an orthopaedic perspective: a multicentre retrospective study.

    Science.gov (United States)

    Guner, Savas; Guner, Sukriye Ilkay; Isik, Yasemin; Gormeli, Gokay; Kalender, Ali Murat; Turktas, Ugur; Gokalp, Mehmet Ata; Gozen, Abdurrahim; Isik, Mustafa; Ozkan, Sezai; Turkozu, Tulin; Karadas, Sevdegul; Ceylan, Mehmet Fethi; Ediz, Levent; Bulut, Mehmet; Gunes, Yusuf; Gormeli, Ayse; Erturk, Cemil; Eseoglu, Metehan; Dursun, Recep

    2013-01-01

    This is a descriptive analysis, of victims of Turkey's October 23, 2011 and November 21, 2011 Van earthquakes. The goal of this study is investigated the injury profile of the both earthquakes in relation to musculoskeletal trauma. We retrospectively reviewed medical records of 3,965 patients admitted to in seven hospitals. A large share of these injuries were soft tissue injuries, followed by fractures, crush injuries, crush syndromes, nerve injuries, vascular injuries, compartment syndrome and joint dislocations. A total of 73 crush injuries were diagnosed and 31 of them were developed compartment syndrome. The patients with closed undisplaced fractures were treated with casting braces. For closed unstable fractures with good skin and soft-tissue conditions, open reduction and internal fixation was performed. All patients with open fracture had an external fixator applied after adequate debridement. Thirty one of 40 patients with compartment syndrome were treated by fasciotomy. For twelve of them, amputation was necessary. The most common procedure performed was debridement, followed by open reduction and internal fixation and closed reduction-casting, respectively. The results of this study may provide the basis for future development of strategy to optimise attempts at rescue and plan treatment of survivors with musculoskeletal injuries after earthquakes.

  6. An Instrument for the Systematic Study of Advertising Creative Appeals.

    Science.gov (United States)

    Secrist, Mark

    Although the generation of creative appeals is the heart and soul of advertising, there has been little methodology developed for the classification and study of the appeals themselves. The paper recommends the use of an instrument which provides a technique that will enable the advertising researcher to develop descriptive studies of ad appeals.…

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

    Science.gov (United States)

    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

  8. How did the Canterbury earthquakes affect physiotherapists and physiotherapy services? A qualitative study.

    Science.gov (United States)

    Mulligan, Hilda; Smith, Catherine M; Ferdinand, Sandy

    2015-03-01

    The recent earthquakes in Canterbury New Zealand ended lives and resulted in disruption to many aspect of life for survivors, including physiotherapists. Physiotherapists often volunteer vital rehabilitation services in the wake of global disasters; however, little is known about how physiotherapists cope with disasters that affect their own communities. The purpose of this study was to investigate how the Canterbury earthquakes affected physiotherapists and physiotherapy services. We use a General Inductive Approach to analyse data obtained from purposively sampled physiotherapists or physiotherapy managers in the Canterbury region. Interviews were audio-recorded and transcribed verbatim. We analysed data from interviews with 27 female and six male participants. We identified four themes: 'A life-changing earthquake' that described how both immediate and on-going events led to our second theme 'Uncertainty'. Uncertainty eroded feelings of resilience, but this was tempered by our third theme 'Giving and receiving support'. Throughout these three themes, we identified a further theme 'Being a physiotherapist'. This theme explains how physiotherapists and physiotherapy services were and still are affected by the Canterbury earthquakes. We recommend that disaster planning occurs at individual, departmental, practice and professional levels. This planning will enable physiotherapists to better cope in the event of a disaster and would help to provide professional bodies with a cohesive set of skills that can be shared with health agencies and rescue organizations. We recommend that the apparently vital skill of listening is explored through further research in order for it to be better accepted as a core physiotherapy skill. Copyright © 2014 John Wiley & Sons, Ltd.

  9. Earthquake strong ground motion studies at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Wong, Ivan; Silva, W.; Darragh, R.; Stark, C.; Wright, D.; Jackson, S.; Carpenter, G.; Smith, R.; Anderson, D.; Gilbert, H.; Scott, D.

    1989-01-01

    Site-specific strong earthquake ground motions have been estimated for the Idaho National Engineering Laboratory assuming that an event similar to the 1983 M s 7.3 Borah Peak earthquake occurs at epicentral distances of 10 to 28 km. The strong ground motion parameters have been estimated based on a methodology incorporating the Band-Limited-White-Noise ground motion model coupled with Random Vibration Theory. A 16-station seismic attenuation and site response survey utilizing three-component portable digital seismographs was also performed for a five-month period in 1989. Based on the recordings of regional earthquakes, the effects of seismic attenuation in the shallow crust and along the propagation path and local site response were evaluated. This data combined with a detailed geologic profile developed for each site based principally on borehole data, was used in the estimation of the strong ground motion parameters. The preliminary peak horizontal ground accelerations for individual sites range from approximately 0.15 to 0.35 g. Based on the authors analysis, the thick sedimentary interbeds (greater than 20 m) in the basalt section attenuate ground motions as speculated upon in a number of previous studies

  10. Mexican Earthquakes and Tsunamis Catalog Reviewed

    Science.gov (United States)

    Ramirez-Herrera, M. T.; Castillo-Aja, R.

    2015-12-01

    Today the availability of information on the internet makes online catalogs very easy to access by both scholars and the public in general. The catalog in the "Significant Earthquake Database", managed by the National Center for Environmental Information (NCEI formerly NCDC), NOAA, allows access by deploying tabular and cartographic data related to earthquakes and tsunamis contained in the database. The NCEI catalog is the product of compiling previously existing catalogs, historical sources, newspapers, and scientific articles. Because NCEI catalog has a global coverage the information is not homogeneous. Existence of historical information depends on the presence of people in places where the disaster occurred, and that the permanence of the description is preserved in documents and oral tradition. In the case of instrumental data, their availability depends on the distribution and quality of seismic stations. Therefore, the availability of information for the first half of 20th century can be improved by careful analysis of the available information and by searching and resolving inconsistencies. This study shows the advances we made in upgrading and refining data for the earthquake and tsunami catalog of Mexico since 1500 CE until today, presented in the format of table and map. Data analysis allowed us to identify the following sources of error in the location of the epicenters in existing catalogs: • Incorrect coordinate entry • Place name erroneous or mistaken • Too general data that makes difficult to locate the epicenter, mainly for older earthquakes • Inconsistency of earthquakes and the tsunami occurrence: earthquake's epicenter located too far inland reported as tsunamigenic. The process of completing the catalogs directly depends on the availability of information; as new archives are opened for inspection, there are more opportunities to complete the history of large earthquakes and tsunamis in Mexico. Here, we also present new earthquake and

  11. Earthquakes and economic growth

    OpenAIRE

    Fisker, Peter Simonsen

    2012-01-01

    This study explores the economic consequences of earthquakes. In particular, it is investigated how exposure to earthquakes affects economic growth both across and within countries. The key result of the empirical analysis is that while there are no observable effects at the country level, earthquake exposure significantly decreases 5-year economic growth at the local level. Areas at lower stages of economic development suffer harder in terms of economic growth than richer areas. In addition,...

  12. Study on tsunami due to offshore earthquakes for Korea coast. Literature survey and numerical simulation on earthquake and tsunami in the Japan Sea and the East China Sea

    International Nuclear Information System (INIS)

    Matsuyama, Masafumi; Aoyagi, Yasuhira; Inoue, Daiei; Choi, Weon-Hack; Kang, Keum-Seok

    2008-01-01

    In Korea, there has been a concern on tsumami risks for the Nuclear Power Plants since the 1983 Nihonkai-Chubu earthquake tsunami. The maximum run-up height reached 4 m to north of the Ulchin nuclear power plant site. The east coast of Korea was also attacked by a few meters high tsunami generated by the 1993 Hokkaido Nansei-Oki earthquake. Both source areas of them were in the areas western off Hokkaido to the eastern margin of the Japan Sea, which remains another tsunami potential. Therefore it is necessary to study tsunami risks for coast of Korea by means of geological investigation and numerical simulation. Historical records of earthquake and tsunami in the Japan Sea were re-compiled to evaluate tsunami potential. A database of marine active faults in the Japan Sea was compiled to decide a regional potential of tsunami. Many developed reverse faults are found in the areas western off Hokkaido to the eastern margin of the Japan Sea. The authors have found no historical earthquake in the East China Sea which caused tunami observed at coast of Korea. Therefore five fault models were determined on the basis of the analysis results of historical records and recent research results of fault parameter and tunami. Tsunami heights were estimated by numerical simulation of nonlinear dispersion wave theory. The results of the simulations indicate that the tsunami heights in these cases are less than 0.25 m along the coast of Korea, and the tsunami risk by these assumed faults does not lead to severe impact. It is concluded that tsunami occurred in the areas western off Hokkaido to the eastern margin of the Japan Sea leads the most significant impact to Korea consequently. (author)

  13. Crowdsourcing Rapid Assessment of Collapsed Buildings Early after the Earthquake Based on Aerial Remote Sensing Image: A Case Study of Yushu Earthquake

    Directory of Open Access Journals (Sweden)

    Shuai Xie

    2016-09-01

    Full Text Available Remote sensing (RS images play a significant role in disaster emergency response. Web2.0 changes the way data are created, making it possible for the public to participate in scientific issues. In this paper, an experiment is designed to evaluate the reliability of crowdsourcing buildings collapse assessment in the early time after an earthquake based on aerial remote sensing image. The procedure of RS data pre-processing and crowdsourcing data collection is presented. A probabilistic model including maximum likelihood estimation (MLE, Bayes’ theorem and expectation-maximization (EM algorithm are applied to quantitatively estimate the individual error-rate and “ground truth” according to multiple participants’ assessment results. An experimental area of Yushu earthquake is provided to present the results contributed by participants. Following the results, some discussion is provided regarding accuracy and variation among participants. The features of buildings labeled as the same damage type are found highly consistent. This suggests that the building damage assessment contributed by crowdsourcing can be treated as reliable samples. This study shows potential for a rapid building collapse assessment through crowdsourcing and quantitatively inferring “ground truth” according to crowdsourcing data in the early time after the earthquake based on aerial remote sensing image.

  14. A study on feature analysis for musical instrument classification.

    Science.gov (United States)

    Deng, Jeremiah D; Simmermacher, Christian; Cranefield, Stephen

    2008-04-01

    In tackling data mining and pattern recognition tasks, finding a compact but effective set of features has often been found to be a crucial step in the overall problem-solving process. In this paper, we present an empirical study on feature analysis for recognition of classical instrument, using machine learning techniques to select and evaluate features extracted from a number of different feature schemes. It is revealed that there is significant redundancy between and within feature schemes commonly used in practice. Our results suggest that further feature analysis research is necessary in order to optimize feature selection and achieve better results for the instrument recognition problem.

  15. Earthquake prediction

    International Nuclear Information System (INIS)

    Ward, P.L.

    1978-01-01

    The state of the art of earthquake prediction is summarized, the possible responses to such prediction are examined, and some needs in the present prediction program and in research related to use of this new technology are reviewed. Three basic aspects of earthquake prediction are discussed: location of the areas where large earthquakes are most likely to occur, observation within these areas of measurable changes (earthquake precursors) and determination of the area and time over which the earthquake will occur, and development of models of the earthquake source in order to interpret the precursors reliably. 6 figures

  16. Musical Expression: An Observational Study of Instrumental Teaching

    Science.gov (United States)

    Karlsson, Jessika; Juslin, Patrik N.

    2008-01-01

    Research has shown that both music students and teachers think that expression is important. Yet, we know little about how expression is taught to students. Such knowledge is needed in order to enhance teaching of expression. The aim of this study was thus to explore the nature of instrumental music teaching in its natural context, with a focus on…

  17. From Seismic Scenarios to Earthquake Risk Assessment: A Case Study for Iquique, Chile.

    Science.gov (United States)

    Aguirre, P.; Fortuno, C.; Martin, J. C. D. L. L.; Vasquez, J.

    2015-12-01

    Iquique is a strategic city and economic center in northern Chile, and is located in a large seismic gap where a megathrust earthquake and tsunami is expected. Although it was hit by a Mw 8.2 earthquake on April 1st 2014, which caused moderate damage, geophysical evidence still suggests that there is potential for a larger event, so a thorough risk assessment is key to understand the physical, social, and economic effects of such potential event, and devise appropriate mitigation plans. Hence, Iquique has been selected as a prime study case for the implementation of a risk assessment platform in Chile. Our study integrates research on three main elements of risk calculations: hazard evaluation, exposure model, and physical vulnerabilities. To characterize the hazard field, a set of synthetic seismic scenarios have been developed based on plate interlocking and the residual slip potential that results from subtracting the slip occurred during the April 1st 2014 rupture fault mechanism, obtained using InSAR+GPS inversion. Additional scenarios were developed based of the fault rupture model of the Maule 2010 Mw 8.8 earthquake and on the local plate locking models in northern Chile. These rupture models define a collection of possible realizations of earthquake geometries parameterized in terms of critical variables like slip magnitude, rise time, mean propagation velocity, directivity, and other, which are propagated to obtain a hazard map for Iquique (e.g. PGA, PGV, PDG). Furthermore, a large body of public and local data was used to construct a detailed exposure model for Iquique, including aggregated building count, demographics, essential facilities, and lifelines. This model together with the PGA maps for the April 1st 2014 earthquake are used to calibrate HAZUS outputs against observed damage, and adjust the fragility curves of physical systems according to more detailed analyses of typical Chilean building types and their structural properties, plus historical

  18. Studying the Mars atmosphere using a SOIR Instrument

    Science.gov (United States)

    Drummond, R.; Vandaele, A.; Daerden, F.; Neefs, E.; Mahieux, A.; Wilquet, V.; Montmessin, F.; Bertaux, J.; McConnell, J. C.; Kaminski, J. W.

    2009-05-01

    SOIR (Solar Occultation InfraRed spectrometer) is currently part of the SPICAV/SOIR instrument on board the Venus Express orbiter (VEX). SOIR, an Echelle infrared spectrometer using an acousto-optic tunable filter (AOTF) for the order selection, is probing the atmosphere by solar occultation, operating between 2.2 and 4.3 μm, with a resolution of 0.15 cm-1. This spectral range is suitable for the detection of several key components of planetary atmospheres, including H2O and its isotopologue HDO, CH4 and other trace species. The SOIR instrument was designed to have a minimum of moving parts, to be light and compact in order to fit on top of the SPICAV instrument. The AOTF allows a narrow range of wavelengths to pass, according to the radio frequency applied to the TeO2 crystal; this selects the order. The advantage of the AOTF is that different orders can be observed quickly and easily during one occultation. To obtain a compact optical scheme, a Littrow configuration was implemented in which the usual collimating and imaging lenses are merged into a single off-axis parabolic mirror. The light is diffracted on the echelle grating, where orders overlap and addition occurs, and finally is recorded by the detector. The detector is 320x256 pixels and is cooled to 88K during an occultation measurement, to maximise the signal to noise ratio. SOIR on VEX has been in orbit around Venus since April 2006, allowing us to characterise the instrument and study its performance. These data have allowed the engineering team to devise several instrumental improvements. The next step in further improving the readiness for Martian atmospheric studies comes in close collaboration with the Mars Atmospheric Modelling group at BIRA-IASB. A General Circulation Model is used to simulate the Martian atmosphere. Currently work is underway with SPICAM data to verify the GCM inputs and outputs. Later the GCM output will be used as feedback for instrumental design of both an improved version

  19. Background studies: earthquake effects on underground radioactive waste repositories

    International Nuclear Information System (INIS)

    1986-05-01

    Results of the first stage of a programme of work leading to the development of a seismicity sub-model for the TIME2 simulation code and its successor(s) are presented. Potential future seismic activity levels in Britain are presented, within the context of historic seismicity (the last 800 years), tectonic activity and the effects of glacial advance and retreat. Methodological approaches to the estimation of seismic hazard due to faulting and ground shaking are presented. Seismic effects on rock and soil properties are also reviewed. Finally, recommendations for further studies are made. (author)

  20. The severity of an earthquake

    Science.gov (United States)

    ,

    1997-01-01

    The severity of an earthquake can be expressed in terms of both intensity and magnitude. However, the two terms are quite different, and they are often confused. Intensity is based on the observed effects of ground shaking on people, buildings, and natural features. It varies from place to place within the disturbed region depending on the location of the observer with respect to the earthquake epicenter. Magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake. It is based on the amplitude of the earthquake waves recorded on instruments

  1. A levitation instrument for containerless study of molten materials.

    Science.gov (United States)

    Nordine, Paul C; Merkley, Dennis; Sickel, Jeffrey; Finkelman, Steve; Telle, Rainer; Kaiser, Arno; Prieler, Robert

    2012-12-01

    A new aero-acoustic levitation instrument (AAL) has been installed at the Institute for Mineral Engineering at RWTH University in Aachen, Germany. The AAL employs acoustically stabilized gas jet levitation with laser-beam heating and melting to create a contact-free containerless environment for high temperature materials research. Contamination-free study of liquids is possible at temperatures in excess of 3000 °C and of undercooled liquids at temperatures far below the melting point. Digital control technology advances the art of containerless experiments to obtain long-term levitation stability, allowing new experiments in extreme temperature materials research and to study operation of the levitation instrument itself. Experiments with liquid Al(2)O(3) at temperatures more than 3200 °C, 1200 °C above the melting point, and with liquid Y(3)Al(5)O(12) far below the melting point are reported. Fast pyrometry and video recording instruments yield crystallization rates in undercooled liquid Al(2)O(3) as a function of temperature. Levitation of dense liquid HfO(2) at temperatures above 2900 °C is demonstrated. Capabilities are described for resonant frequency matching in the three-axis acoustic positioning system, acoustic control of sample spin, and position control of standing wave nodes to stabilize levitation under changing experimental conditions. Further development and application of the levitation technology is discussed based on the results of experiments and modeling of instrument operations.

  2. The impact of major earthquakes on the psychological functioning of medical students: a Christchurch, New Zealand study.

    Science.gov (United States)

    Carter, Frances A; Bell, Caroline J; Ali, Anthony N; McKenzie, Janice; Wilkinson, Timothy J

    2014-07-18

    No previous studies have systematically assessed the psychological functioning of medical students following a major disaster. To describe the psychological functioning of medical students following the earthquakes in Canterbury, New Zealand, and identify predictors of adverse psychological functioning. 7 months following the most severe earthquake, medical students completed the Depression, Anxiety and Stress Scale (DASS), the Post-Traumatic Stress Disorder Checklist, the Eysenck Personality Questionnaire, the Connor Davidson Resilience Scale, the Work and Adjustment Scale, and Likert scales assessing psychological functioning at worst and currently. A substantial minority of medical students reported moderate-extreme difficulties on the DASS subscales 7 months following the most severe earthquake (Depression =12%; Anxiety =9%; Stress =10%). Multiple linear modelling produced a model that predicted 27% of the variance in total scores on the DASS. Variables contributing significantly to the model were: year of medical course, presence of mental health problems prior to the earthquakes, not being New Zealand European, and being higher on retrospectively rated neuroticism prior to the earthquakes. Around 10% of medical students experienced moderate-extreme psychological difficulties 7 months following the most severe earthquake on 22 February 2011. Specific groups at high risk for ongoing psychological symptomatology were able to be identified.

  3. Numerical modeling of block structure dynamics: Application to the Vrancea region and study of earthquakes sequences in the synthetic catalogs

    International Nuclear Information System (INIS)

    Soloviev, A.A.; Vorobieva, I.A.

    1995-08-01

    A seismically active region is represented as a system of absolutely rigid blocks divided by infinitely thin plane faults. The interaction of the blocks along the fault planes and with the underlying medium is viscous-elastic. The system of blocks moves as a consequence of prescribed motion of boundary blocks and the underlying medium. When for some part of a fault plane the stress surpasses a certain strength level a stress-drop (''a failure'') occurs. It can cause a failure for other parts of fault planes. The failures are considered as earthquakes. As a result of the numerical simulation a synthetic earthquake catalogue is produced. This procedure is applied for numerical modeling of dynamics of the block structure approximating the tectonic structure of the Vrancea region. By numerical experiments the values of the model parameters were obtained which supplied the synthetic earthquake catalog with the space distribution of epicenters close to the real distribution of the earthquake epicenters in the Vrancea region. The frequency-magnitude relations (Gutenberg-Richter curves) obtained for the synthetic and real catalogs have some common features. The sequences of earthquakes arising in the model are studied for some artificial structures. It is found that ''foreshocks'', ''main shocks'', and ''aftershocks'' could be detected among earthquakes forming the sequences. The features of aftershocks, foreshocks, and catalogs of main shocks are analysed. (author). 5 refs, 12 figs, 16 tabs

  4. Prevalence of insomnia among residents of Tokyo and osaka after the great East Japan earthquake: a prospective study.

    Science.gov (United States)

    Sugiura, Hiroaki; Akahane, Manabu; Ohkusa, Yasushi; Okabe, Nobuhiko; Sano, Tomomi; Jojima, Noriko; Bando, Harumi; Imamura, Tomoaki

    2013-01-18

    The Great East Japan Earthquake occurred on March 11, 2011. Tokyo and Osaka, which are located 375 km and 750 km, respectively, from the epicenter, experienced tremors of 5.0 lower and 3.0 seismic intensity on the Japan Meteorological Agency scale. The Great East Japan Earthquake was the fourth largest earthquake in the world and was accompanied by a radioactive leak at a nuclear power plant and a tsunami. In the aftermath of a disaster, some affected individuals presented to mental health facilities with acute stress disorder (ASD) and/or post-traumatic stress disorder (PTSD). However, few studies have addressed mental stress problems other than ASD or PTSD among the general public immediately after a disaster. Further, the effects of such a disaster on residents living at considerable distances from the most severely affected area have not been examined. This study aimed to prospectively analyze the effect of a major earthquake on the prevalence of insomnia among residents of Tokyo and Osaka. A prospective online questionnaire study was conducted in Tokyo and Osaka from January 20 to April 30, 2011. An Internet-based questionnaire, intended to be completed daily for a period of 101 days, was used to collect the data. All of the study participants lived in Tokyo or Osaka and were Consumers' Co-operative Union (CO-OP) members who used an Internet-based food-ordering system. The presence or absence of insomnia was determined before and after the earthquake. These data were compared after stratification for the region and participants' age. Multivariate analyses were conducted using logistic regression and a generalized estimating equation. This study was conducted with the assistance of the Japanese CO-OP. The prevalence of insomnia among adults and minors in Tokyo and adults in Osaka increased significantly after the earthquake. No such increase was observed among minors in Osaka. The overall adjusted odds ratios for the risk of insomnia post-earthquake versus pre-earthquake

  5. The continuous automatic monitoring network installed in Tuscany (Italy) since late 2002, to study earthquake precursory phenomena

    Science.gov (United States)

    Pierotti, Lisa; Cioni, Roberto

    2010-05-01

    monitoring stations. This has been carried out on the basis of: i) hydrogeologic and structural studies in order to assess the underground fluid circulation regime; ii) a detailed geochemical study of all the natural manifestations present in the selected territories, such as cold and hot springs and gas emission zones; iii) logistical aspects. Therefore, a detailed hydrogeochemical study was performed in 2002. A total of 150 water points were sampled in Garfagnana/Lunigiana area (N-W Tuscany) and analysed. Based on the results of this multidisciplinary study, five water points suitable for the installation of the monitoring stations, were selected. They are: Bagni di Lucca (Bernabò spring), Gallicano (Capriz spring) and Pieve Fosciana (Prà di Lama spring) in Garfagnana, Equi Terme (main spring feeding the swimming pool of the thermal resort) and Villafranca in Lunigiana (well feeding the public swimming pool). In the Amiata area, in the preliminary campaign, 69 water points were sampled and analyzed and five sites were selected. They are Piancastagnaio, Santa Fiora, Pian dei Renai and Bagnore, which are fed by the volcanic aquifer, and Bagno Vignoni borehole, which is fed by the evaporite carbonate aquifer. The installation and start-up process of the monitoring systems in the Garfagnana-Lunigiana area begun in November 2002; in the Monte Amiata region it begun in June 2003. From the day of installation, a periodic water sampling and manual measurement of the main physical and physicochemical parameters have been carried out on a monthly basis. Such activity has the double function of performing a cross-check of the monitoring instrumentation, and carrying out additional chemical and isotopic analysis. The continuous automatic monitoring stations operate with flowing water (about 5 litres per minute) and record the following parameters: temperature (T), pH, electrical conductivity (EC), redox potential (ORP) and the content of CO2 and CH4 dissolved in water. Data are

  6. Earthquake and Physical and Social Vulnerability Assessment for Settlements: Case Study Avcılar District

    Directory of Open Access Journals (Sweden)

    Görün ARUN

    2010-01-01

    Full Text Available Many settled areas in Turkey and across the globe suffer economical and social losses resulting from natural disasters such as earthquakes, floods, hurricanes and landslides. In this study, a vulnerability assessment model has been developed for earthquake prone areas in Turkey. The vulnerability assessment model includes ground factors, a building’s physical conditions, building evacuation and social (demographic and socioeconomic aspects of the settlement. The ground vulnerability factor is calculated using factors such as the earthquake zone, soil classification, land sliding and liquefaction threats. The physical vulnerability factor depends on the structural and non-structural threats of the building; the building evacuation vulnerability factor includes the position and structural system of the staircase, the width and natural illumination of the evacuation route, the size and opening of the building exit doors to the street and the distance of the building to the closest open area. The social vulnerability factor considers the age group, gender, family type, education, ownership, income etc of the building users. This vulnerability assessment model is applied to a case study - that of the Avcılar district of Istanbul. Forty different reinforced concrete residential buildings (349 apartments of 1225 people are assessed using the develop checklist. In order to evaluate the checklist and to assess the importance (relevance of vulnerability factors, a questionnaire is forwarded to various related professional groups (architecture, urban planning and civil engineering. The results of the questionnaire are examined using SPSS software with factor analysis. According to the results, most of the samples in the case study area can be classified as high vulnerable.

  7. Integrated study of geophysical and biological anomalies before earthquakes (seismic and non-seismic), in Austria and Indonesia

    Science.gov (United States)

    Straka, Wolfgang; Assef, Rizkita; Faber, Robert; Ferasyi, Reza

    2015-04-01

    Earthquakes are commonly seen as unpredictable. Even when scientists believe an earthquake is likely, it is still hard to understand the indications observed, as well as their theoretical and practical implications. There is some controversy surrounding the concept of using animals as a precursor of earthquakes. Nonetheless, several institutes at University of Natural Resources and Life Sciences, and Vienna University of Technology, both Vienna, Austria, and Syiah Kuala University, Banda Aceh, as well as Terramath Indonesia, Buleleng, both Indonesia, cooperate in a long-term project, funded by Red Bull Media House, Salzburg, Austria, which aims at getting some decisive step forward from anecdotal to scientific evidence of those interdependencies, and show their possible use in forecasting seismic hazard on a short-term basis. Though no conclusive research has yet been published, an idea in this study is that even if animals do not respond to specific geophysical precursors and with enough notice to enable earthquake forecasting on that basis, they may at least enhance, in conjunction with other indications, the degree of certainty we can get of a prediction of an impending earthquake. In Indonesia, indeed, before the great earthquakes of 2004 and 2005, ominous geophysical as well as biological phenomena occurred (but were realized as precursors only in retrospect). Numerous comparable stories can be told from other times and regions. Nearly 2000 perceptible earthquakes (> M3.5) occur each year in Indonesia. Also, in 2007, the government has launched a program, focused on West Sumatra, for investigating earthquake precursors. Therefore, Indonesia is an excellent target area for a study concerning possible interconnections between geophysical and biological earthquake precursors. Geophysical and atmospheric measurements and behavioral observation of several animal species (elephant, domestic cattle, water buffalo, chicken, rat, catfish) are conducted in three areas

  8. Study of Earthquake Disaster Prediction System of Langfang city Based on GIS

    Science.gov (United States)

    Huang, Meng; Zhang, Dian; Li, Pan; Zhang, YunHui; Zhang, RuoFei

    2017-07-01

    In this paper, according to the status of China’s need to improve the ability of earthquake disaster prevention, this paper puts forward the implementation plan of earthquake disaster prediction system of Langfang city based on GIS. Based on the GIS spatial database, coordinate transformation technology, GIS spatial analysis technology and PHP development technology, the seismic damage factor algorithm is used to predict the damage of the city under different intensity earthquake disaster conditions. The earthquake disaster prediction system of Langfang city is based on the B / S system architecture. Degree and spatial distribution and two-dimensional visualization display, comprehensive query analysis and efficient auxiliary decision-making function to determine the weak earthquake in the city and rapid warning. The system has realized the transformation of the city’s earthquake disaster reduction work from static planning to dynamic management, and improved the city’s earthquake and disaster prevention capability.

  9. Earthquakes and Earthquake Engineering. LC Science Tracer Bullet.

    Science.gov (United States)

    Buydos, John F., Comp.

    An earthquake is a shaking of the ground resulting from a disturbance in the earth's interior. Seismology is the (1) study of earthquakes; (2) origin, propagation, and energy of seismic phenomena; (3) prediction of these phenomena; and (4) investigation of the structure of the earth. Earthquake engineering or engineering seismology includes the…

  10. Hepatitis E virus seroepidemiology: a post-earthquake study among blood donors in Nepal

    Directory of Open Access Journals (Sweden)

    Ashish C. Shrestha

    2016-11-01

    Full Text Available Abstract Background As one of the causative agents of viral hepatitis, hepatitis E virus (HEV has gained public health attention globally. HEV epidemics occur in developing countries, associated with faecal contamination of water and poor sanitation. In industrialised nations, HEV infections are associated with travel to countries endemic for HEV, however, autochthonous infections, mainly through zoonotic transmission, are increasingly being reported. HEV can also be transmitted by blood transfusion. Nepal has experienced a number of HEV outbreaks, and recent earthquakes resulted in predictions raising the risk of an HEV outbreak to very high. This study aimed to measure HEV exposure in Nepalese blood donors after large earthquakes. Methods Samples (n = 1,845 were collected from blood donors from Kathmandu, Chitwan, Bhaktapur and Kavre. Demographic details, including age and sex along with possible risk factors associated with HEV exposure were collected via a study-specific questionnaire. Samples were tested for HEV IgM, IgG and antigen. The proportion of donors positive for HEV IgM or IgG was calculated overall, and for each of the variables studied. Chi square and regression analyses were performed to identify factors associated with HEV exposure. Results Of the donors residing in earthquake affected regions (Kathmandu, Bhaktapur and Kavre, 3.2% (54/1,686; 95% CI 2.7–4.0% were HEV IgM positive and two donors were positive for HEV antigen. Overall, 41.9% (773/1,845; 95% CI 39.7–44.2% of donors were HEV IgG positive, with regional variation observed. Higher HEV IgG and IgM prevalence was observed in donors who reported eating pork, likely an indicator of zoonotic transmission. Previous exposure to HEV in Nepalese blood donors is relatively high. Conclusion Detection of recent markers of HEV infection in healthy donors suggests recent asymptomatic HEV infection and therefore transfusion-transmission in vulnerable patients is a risk in

  11. Hepatitis E virus seroepidemiology: a post-earthquake study among blood donors in Nepal.

    Science.gov (United States)

    Shrestha, Ashish C; Flower, Robert L P; Seed, Clive R; Rajkarnikar, Manita; Shrestha, Shrawan K; Thapa, Uru; Hoad, Veronica C; Faddy, Helen M

    2016-11-25

    As one of the causative agents of viral hepatitis, hepatitis E virus (HEV) has gained public health attention globally. HEV epidemics occur in developing countries, associated with faecal contamination of water and poor sanitation. In industrialised nations, HEV infections are associated with travel to countries endemic for HEV, however, autochthonous infections, mainly through zoonotic transmission, are increasingly being reported. HEV can also be transmitted by blood transfusion. Nepal has experienced a number of HEV outbreaks, and recent earthquakes resulted in predictions raising the risk of an HEV outbreak to very high. This study aimed to measure HEV exposure in Nepalese blood donors after large earthquakes. Samples (n = 1,845) were collected from blood donors from Kathmandu, Chitwan, Bhaktapur and Kavre. Demographic details, including age and sex along with possible risk factors associated with HEV exposure were collected via a study-specific questionnaire. Samples were tested for HEV IgM, IgG and antigen. The proportion of donors positive for HEV IgM or IgG was calculated overall, and for each of the variables studied. Chi square and regression analyses were performed to identify factors associated with HEV exposure. Of the donors residing in earthquake affected regions (Kathmandu, Bhaktapur and Kavre), 3.2% (54/1,686; 95% CI 2.7-4.0%) were HEV IgM positive and two donors were positive for HEV antigen. Overall, 41.9% (773/1,845; 95% CI 39.7-44.2%) of donors were HEV IgG positive, with regional variation observed. Higher HEV IgG and IgM prevalence was observed in donors who reported eating pork, likely an indicator of zoonotic transmission. Previous exposure to HEV in Nepalese blood donors is relatively high. Detection of recent markers of HEV infection in healthy donors suggests recent asymptomatic HEV infection and therefore transfusion-transmission in vulnerable patients is a risk in Nepal. Surprisingly, this study did not provide evidence of a large

  12. Deep seismic transect across the Tonankai earthquake area obtained from the onshore- offshore wide-angle seismic study

    Science.gov (United States)

    Nakanishi, A.; Obana, K.; Kodaira, S.; Miura, S.; Fujie, G.; Ito, A.; Sato, T.; Park, J.; Kaneda, Y.; Ito, K.; Iwasaki, T.

    2008-12-01

    In the Nankai Trough subduction seismogenic zone, M8-class great earthquake area can be divided into three segments; they are source regions of the Nankai, Tonankai and presumed Tokai earthquakes. The Nankai and Tonankai earthquakes had often occurred simultaneously, and caused a great event. Hypocenters of these great earthquakes were usually located off the cape Shiono, Kii Peninsula, and the rupture propagated westwards and eastwards, respectively. To obtain the deep structure of the down-dip limit of around the Nankai Trough seismogenic zone, the segment boundary and first break area off the Kii Peninsula, the onshore-offshore wide-angle seismic studies was conducted in the western and eastern part of the Kii Peninsula and their offshore area in 2004 and 2006, respectively. The result of the seismic study in 2004 is mainly shown here. Structural images along the onshore and offshore profiles have already been separately obtained. In this study, an onshore-offshore integrated image of the western part of the Kii Peninsula, ~400km in a total length, is obtained from first arrival tomography and traveltime mapping of reflection phases by combining dataset of 13 land explosions, 2269 land stations, 36 OBSs and 1806 offshore airgun shots. The subduction angle of the Philippine Sea plate (PSP) gradually increases landward up to ~20-25 degree. Beneath the onshore part, the subducting PSP is estimated at ~5km shallower than that previously derived from seismicity. Low frequency earthquakes (identified and picked by Japan Meteorological Agency) are relocated around the plate interface of the subducting PSP by using the deep seismic transect obtained in this study. The offshore 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 (MEXT). The onshore research carried by the Kyoto University is part of 'Special Project for

  13. Modelling end-glacial earthquakes at Olkiluoto. Expansion of the 2010 study

    Energy Technology Data Exchange (ETDEWEB)

    Faelth, B.; Hoekmark, H. [Clay Technology AB, Lund (Sweden)

    2012-02-15

    The present report is an extension of Posiva working report 2011-13: 'Modelling end-glacial earthquakes at Olkiluoto'. The modelling methodology and most parameter values are identical to those used in that report. The main objective is the same: to obtain conservative estimates of fracture shear displacements induced by end-glacial earthquakes occurring on verified deformation zones at the Olkiluoto site. The remotely activated rock fractures (with their fracture centres positioned at different distances around the potential earthquake fault being considered) are called 'target fractures'. As in the previous report, all target fractures were assumed to be perfectly planar and circular with a radius of 75 m. Compared to the previous study, the result catalogue is more complete. One additional deformation zone (i.e. potential earthquake fault) has been included (BFZ039), whereas one deformation zone that appeared to produce only insignificant target fracture disturbances (BFZ214) is omitted. For each of the three zones considered here (BFZ021, BFZ039, and BFZ100), four models, each with a different orientation of the target fractures surrounding the fault, are analysed. Three of these four sets were included in the previous report, however not as systematically as here where each of the four fracture orientations is tried in all fracture positions. As in the previous study, seismic moments and moment magnitudes are as high as reasonably possible, given the sizes and orientations of the zones, i.e., the earthquakes release the largest possible amount of strain energy. The strain energy release is restricted only by a low residual fault shear strength applied to suppress post-rupture fault oscillations. Moment magnitudes are: 5.8 (BFZ021), 3.9 (BFZ039) and 4.3 (BFZ100). For the BFZ100 model, the sensitivity of the results to variations in fracture shear strength is checked. The BFZ021 and BFZ100 models are analyzed for two additional in situ stress

  14. Adaptively smoothed seismicity earthquake forecasts for Italy

    Directory of Open Access Journals (Sweden)

    Yan Y. Kagan

    2010-11-01

    Full Text Available We present a model for estimation of the probabilities of future earthquakes of magnitudes m ≥ 4.95 in Italy. This model is a modified version of that proposed for California, USA, by Helmstetter et al. [2007] and Werner et al. [2010a], and it approximates seismicity using a spatially heterogeneous, temporally homogeneous Poisson point process. The temporal, spatial and magnitude dimensions are entirely decoupled. Magnitudes are independently and identically distributed according to a tapered Gutenberg-Richter magnitude distribution. We have estimated the spatial distribution of future seismicity by smoothing the locations of past earthquakes listed in two Italian catalogs: a short instrumental catalog, and a longer instrumental and historic catalog. The bandwidth of the adaptive spatial kernel is estimated by optimizing the predictive power of the kernel estimate of the spatial earthquake density in retrospective forecasts. When available and reliable, we used small earthquakes of m ≥ 2.95 to reveal active fault structures and 29 probable future epicenters. By calibrating the model with these two catalogs of different durations to create two forecasts, we intend to quantify the loss (or gain of predictability incurred when only a short, but recent, data record is available. Both forecasts were scaled to five and ten years, and have been submitted to the Italian prospective forecasting experiment of the global Collaboratory for the Study of Earthquake Predictability (CSEP. An earlier forecast from the model was submitted by Helmstetter et al. [2007] to the Regional Earthquake Likelihood Model (RELM experiment in California, and with more than half of the five-year experimental period over, the forecast has performed better than the others.

  15. A Geodynamic Study of Active Crustal Deformation and Earthquakes in North China

    Science.gov (United States)

    Yang, Y.; Liu, M.

    2005-12-01

    North China is part of the Archaean Sino-Korean craton, yet today it is a region of intense crustal deformation and earthquakes, including 21 M >=7.0 events since 512 AD. More than half of the large events occurred within the Fen-Wei rift system surrounding the stable Ordos plateau; the largest events (M >=7.3) show a sequential southward migration along the rift. However, since 1695 the Fen-Wei rift has became seismically dormant, while seismicity seems having shifted eastward to the North China plain, marked by the 1996 Tangshan earthquake (M=7.8). We have developed a 3D viscoelastic geodynamic model to study the cause of seismicity and its spatial-temporal pattern in North China. Constrained by crustal kinematics from GPS and neotectonic data, the model shows high deviatoric stress in the North China crust, resulting mainly from compression of the expanding Tibetan Plateau and resistance from the stable Siberian block. Within North China seismicity is largely controlled by lateral heterogeneity of lithospheric structures, which explains the concentration of seismicity in the Fen-Wei rift. Our results show that stress triggering may have contributed to the sequential migration of large events along the rift, and the release and migration of stress and strain energy from these large events may partially explain the intense seismicity in the North China plain in the past 300 years. Comparing the predicted long-term spatial pattern of strain energy with seismic energy release provides some insights of potential earthquake risks in North China.

  16. A pilot study of the Earthquake Precursors in the Southwest Peloponnes, Greece

    Science.gov (United States)

    Velez, A. P.; Tsinganos, K.; Karastathis, V. K.; Kafatos, M.; Ouzounov, D.; Papadopoulos, G. A.; Tselentis, A.; Eleftheriou, G.; Mouzakiotis, E.; Gika, F.; Aspiotis, T.; Liakopoulos, S.; Voulgaris, N.

    2016-12-01

    A seismic array of the most contemporary technology has been recently installed in the area of Southwest Peloponnese, Greece, an area well known for its high seismic activity. The tectonic regime of the Hellenic arc was the reason for many lethal earthquakes with considerable damage to the broader area of East Mediterranean sea. The seismic array is based on nine 32-bit stations with broadband borehole seismometers. The seismogenic region, monitored by the array, is offshore. At this place the earthquake location suffers by poor azimuthal coverage and the stations of the national seismic network are very distant to this area. Therefore, the existing network cannot effectively monitor the microseismicity. The new array achieved a detailed monitoring of the small events dropping considerably the magnitude of completeness. The detectability of the microearthquakes has been drastically improved permitting so the statistical assessment of earthquake sequences in the area. In parallel the monitored seismicity is directly related with Radon measurement in the soil, taken at three stations in the area.. Radon measurements are performed indirectly by means γ-ray spectrometry of its radioactive progenies 214Pb and 214Bi (emitted at 351 keV and 609 keV, respectively). NaI(Tl) detectors have been installed at 1 m depth, at sites in vicinity of faults providing continuous real time data. Local meteorological records for atmospheric corrections are also continuously recorded. According to the Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model atmospheric thermal anomalies observed before strong events can be attributed to increased radon concentration. This is also supported by the statistical analysis of AVHRR/NOAA-18 satellite thermal infrared (TIR) daily records. A combined study of precursor's signals is expected to provide a reliable assessment of their ability on short-term forecasting.

  17. Study on Seismogenesis of 2013 Ms5.1 Badong Earthquake in the Three Gorges Reservoir Region

    Science.gov (United States)

    Li, X.; Zeng, Z.; Xu, S.; He, C.

    2015-12-01

    On 16 December, 2013, an earthquake of Ms5.1 occurred in Badong County, the Three Gorges Reservoir area, China. We collected all the 150 published focal mechanism solutions (FMS) and inversed the tectonic stress field in Badong, the Three Gorges Dam and Huangling anticline area using the software SATSI (Hardebeck and Michael, 2006). Inversion results show that the orientations of maximum principle stress axis (σ1) in Badong plunge to NNE or SSW. Detailed characteristics of the stress field indicate that the σ1 axis is almost vertical in the center of Huangling anticline and turns horizontal to the west. As to deep structures, we studied the satellite gravity anomalies of 8-638 order in this area using the EIGEN-6C2 model provided by ICGRM. Combining the seismic sounding profile through the epicenter of Badong earthquake and the petrology data, we reinterpreted the deep structure in the study area. The results show that the deep crust in Badong is unstable and the deep material's upwelling leads to Huangling anticline continued uplifting, which is consistent with the result indicated from the stress filed. Both of them provide energy for the preparation of earthquake. The FMS shows that Gaoqiao Fault is the causative fault of this Ms5.1 earthquake. Field investigations indicated that the lithology and fracture characteristic in Badong is beneficial to reservoir water infiltration. Before the earthquake, reservoir water level raised to 175m, the highest storage level, which increased the loading. Based on above researches, we believe that the Ms5.1 Badong earthquake is controlled by deep tectonic environment and stress field in shallow crust. The reservoir water infiltration and uploading increase generated by water storage of the Three Gorges area reduced the strength of Gaoqiao Fault and changed its stress state. These factors jointly promoted an abrupt movement of the fault in the critical stress state, and triggered the Ms5.1 Badong earthquake.

  18. Sensitivity analysis and power for instrumental variable studies.

    Science.gov (United States)

    Wang, Xuran; Jiang, Yang; Zhang, Nancy R; Small, Dylan S

    2018-03-31

    In observational studies to estimate treatment effects, unmeasured confounding is often a concern. The instrumental variable (IV) method can control for unmeasured confounding when there is a valid IV. To be a valid IV, a variable needs to be independent of unmeasured confounders and only affect the outcome through affecting the treatment. When applying the IV method, there is often concern that a putative IV is invalid to some degree. We present an approach to sensitivity analysis for the IV method which examines the sensitivity of inferences to violations of IV validity. Specifically, we consider sensitivity when the magnitude of association between the putative IV and the unmeasured confounders and the direct effect of the IV on the outcome are limited in magnitude by a sensitivity parameter. Our approach is based on extending the Anderson-Rubin test and is valid regardless of the strength of the instrument. A power formula for this sensitivity analysis is presented. We illustrate its usage via examples about Mendelian randomization studies and its implications via a comparison of using rare versus common genetic variants as instruments. © 2018, The International Biometric Society.

  19. A Deterministic Approach to Earthquake Prediction

    Directory of Open Access Journals (Sweden)

    Vittorio Sgrigna

    2012-01-01

    Full Text Available The paper aims at giving suggestions for a deterministic approach to investigate possible earthquake prediction and warning. A fundamental contribution can come by observations and physical modeling of earthquake precursors aiming at seeing in perspective the phenomenon earthquake within the framework of a unified theory able to explain the causes of its genesis, and the dynamics, rheology, and microphysics of its preparation, occurrence, postseismic relaxation, and interseismic phases. Studies based on combined ground and space observations of earthquake precursors are essential to address the issue. Unfortunately, up to now, what is lacking is the demonstration of a causal relationship (with explained physical processes and looking for a correlation between data gathered simultaneously and continuously by space observations and ground-based measurements. In doing this, modern and/or new methods and technologies have to be adopted to try to solve the problem. Coordinated space- and ground-based observations imply available test sites on the Earth surface to correlate ground data, collected by appropriate networks of instruments, with space ones detected on board of Low-Earth-Orbit (LEO satellites. Moreover, a new strong theoretical scientific effort is necessary to try to understand the physics of the earthquake.

  20. Historic Eastern Canadian earthquakes

    International Nuclear Information System (INIS)

    Asmis, G.J.K.; Atchinson, R.J.

    1981-01-01

    Nuclear power plants licensed in Canada have been designed to resist earthquakes: not all plants, however, have been explicitly designed to the same level of earthquake induced forces. Understanding the nature of strong ground motion near the source of the earthquake is still very tentative. This paper reviews historical and scientific accounts of the three strongest earthquakes - St. Lawrence (1925), Temiskaming (1935), Cornwall (1944) - that have occurred in Canada in 'modern' times, field studies of near-field strong ground motion records and their resultant damage or non-damage to industrial facilities, and numerical modelling of earthquake sources and resultant wave propagation to produce accelerograms consistent with the above historical record and field studies. It is concluded that for future construction of NPP's near-field strong motion must be explicitly considered in design

  1. Scoping Study Investigating PWR Instrumentation during a Severe Accident Scenario

    Energy Technology Data Exchange (ETDEWEB)

    Rempe, J. L. [Rempe and Associates, LLC, Idaho Falls, ID (United States); Knudson, D. L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lutz, R. J. [Lutz Nuclear Safety Consultant, LLC, Asheville, NC (United States)

    2015-09-01

    significantly exceeded QE limits for extended time periods for the low frequency STSBO sequence evaluated in this study. It is recognized that the core damage frequency (CDF) of the sequence evaluated in this scoping effort would be considerably lower if evaluations considered new FLEX equipment being installed by industry. Nevertheless, because of uncertainties in instrumentation response when exposed to conditions beyond QE limits and alternate challenges associated with different sequences that may impact sensor performance, it is recommended that additional evaluations of instrumentation performance be completed to provide confidence that operators have access to accurate, relevant, and timely information on the status of reactor systems for a broad range of challenges associated with risk important severe accident sequences.

  2. Earthquake Culture: A Significant Element in Earthquake Disaster Risk Assessment and Earthquake Disaster Risk Management

    OpenAIRE

    Ibrion, Mihaela

    2018-01-01

    This book chapter brings to attention the dramatic impact of large earthquake disasters on local communities and society and highlights the necessity of building and enhancing the earthquake culture. Iran was considered as a research case study and fifteen large earthquake disasters in Iran were investigated and analyzed over more than a century-time period. It was found that the earthquake culture in Iran was and is still conditioned by many factors or parameters which are not integrated and...

  3. Study on Repaired Earthquake-Damaged Bridge Piers under Seismic Load

    Directory of Open Access Journals (Sweden)

    Jun Deng

    2015-01-01

    Full Text Available The concrete bridge pier damaged during earthquakes need be repaired to meet the design standards. Steel tube as a traditional material or FRP as a novel material has become popular to repair the damaged reinforced concrete (RC bridge piers. In this paper, experimental and finite element (FE studies are employed to analyze the confinement effectiveness of the different repair materials. The FE method was used to calculate the hysteretic behavior of three predamaged circle RC bridge piers repaired with steel tube, basalt fiber reinforced polymer (BFRP, and carbon fiber reinforced polymer (CFRP, respectively. Meanwhile, the repaired predamaged circle concrete bridge piers were tested by pseudo-static cyclic loading to study the seismic behavior and evaluate the confinement effectiveness of the different repair materials and techniques. The FE analysis and experimental results showed that the repaired piers had similar hysteretic curves with the original specimens and all the three repair techniques can restore the seismic performance of the earthquake-damaged piers. Steel tube jacketing can significantly improve the lateral stiffness and peak load of the damaged pier, while the BFRP and CFRP sheets cannot improve these properties due to their thin thickness.

  4. Laboratory Experiments and Instrument Intercomparison Studies of Carbonaceous Aerosol Particles

    Energy Technology Data Exchange (ETDEWEB)

    Davidovits, Paul [Boston College, Chestnut Hill, MA (United States)

    2015-10-20

    Aerosols containing black carbon (and some specific types of organic particulate matter) directly absorb incoming light, heating the atmosphere. In addition, all aerosol particles backscatter solar light, leading to a net-cooling effect. Indirect effects involve hydrophilic aerosols, which serve as cloud condensation nuclei (CCN) that affect cloud cover and cloud stability, impacting both atmospheric radiation balance and precipitation patterns. At night, all clouds produce local warming, but overall clouds exert a net-cooling effect on the Earth. The effect of aerosol radiative forcing on climate may be as large as that of the greenhouse gases, but predominantly opposite in sign and much more uncertain. The uncertainties in the representation of aerosol interactions in climate models makes it problematic to use model projections to guide energy policy. The objective of our program is to reduce the uncertainties in the aerosol radiative forcing in the two areas highlighted in the ASR Science and Program Plan. That is, (1) addressing the direct effect by correlating particle chemistry and morphology with particle optical properties (i.e. absorption, scattering, extinction), and (2) addressing the indirect effect by correlating particle hygroscopicity and CCN activity with particle size, chemistry, and morphology. In this connection we are systematically studying particle formation, oxidation, and the effects of particle coating. The work is specifically focused on carbonaceous particles where the uncertainties in the climate relevant properties are the highest. The ongoing work consists of laboratory experiments and related instrument inter-comparison studies both coordinated with field and modeling studies, with the aim of providing reliable data to represent aerosol processes in climate models. The work is performed in the aerosol laboratory at Boston College. At the center of our laboratory setup are two main sources for the production of aerosol particles: (a

  5. Joint Urban 2003: Study Overview And Instrument Locations

    Energy Technology Data Exchange (ETDEWEB)

    Allwine, K Jerry; Flaherty, Julia E.

    2006-08-16

    Quality-assured meteorological and tracer data sets are vital for establishing confidence that indoor and outdoor dispersion models used to simulate dispersal of potential toxic agents in urban atmospheres are giving trustworthy results. The U.S. Department of Defense-Defense Threat Reduction Agency and the U.S. Department of Homeland Security joined together to conduct the Joint Urban 2003 atmospheric dispersion study to provide this critically-needed high-resolution dispersion data. This major urban study was conducted from June 28 through July 31, 2003, in Oklahoma City, Oklahoma, with the participation of over 150 scientists and engineers from over 20 U.S. and foreign institutions. The Joint Urban 2003 lead scientist was Jerry Allwine (Pacific Northwest National Laboratory) who oversaw study design, logistical arrangements and field operations with the help of Joe Shinn (Lawrence Livermore National Laboratory), Marty Leach (Lawrence Livermore National Laboratory), Ray Hosker (Atmospheric Turbulence and Diffusion Division), Leo Stockham (Northrop Grumman Information Technology) and Jim Bowers (Dugway Proving Grounds). This report gives a brief overview of the field campaign, describing the scientific objectives, the dates of the intensive observation periods, and the instruments deployed. The data from this field study is available to the scientific community through an on-line database that is managed by Dugway Proving Ground. This report will be included in the database to provide its users with some general information about the field study, and specific information about the instrument coordinates. Appendix A of this document provides the definitive record of the instrument locations during this field campaign, and Appendix B lists all the study principal investigators and participants.

  6. Earthquake engineering and structural dynamics studies at Bhabha Atomic Research Centre

    International Nuclear Information System (INIS)

    Reddy, G.R.; Parulekar, Y.M.; Sharma, A.; Dubey, P.N.; Vaity, K.N.; Kukreja, Mukhesh; Vaze, K.K.; Ghosh, A.K.; Kushwaha, H.S.

    2007-01-01

    Earthquake Engineering and structural Dynamics has gained the attention of many researchers throughout the world and extensive research work is performed. Linear behaviour of structures, systems and components (SSCs) subjected to earthquake/dynamic loading is clearly understood. However, nonlinear behaviour of SSCs subjected to earthquake/dynamic loading need to be understood clearly and design methods need to be validated experimentally. In view of this, three major areas in earthquake engineering and structural dynamics identified for research includes: design and development of passive devices to control the seismic/dynamic response of SSCs, nonlinear behaviour of piping systems subjected to earthquake loading and nonlinear behavior of RCC structures under seismic excitation or dynamic loading. BARC has performed extensive work and also being continued in the above-identified areas. The work performed is helping for clearer understanding of nonlinear behavior of SSCs as well as in developing new schemes, methodologies and devices to control the earthquake response of SSCs. (author)

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

    International Nuclear Information System (INIS)

    Abedi-Nik, Farhad; Sabouri-Ghomi, Saeid

    2008-01-01

    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

  8. Earthquake safety program at Lawrence Livermore National Laboratory

    International Nuclear Information System (INIS)

    Freeland, G.E.

    1985-01-01

    Within three minutes on the morning of January 24, 1980, an earthquake and three aftershocks, with Richter magnitudes of 5.8, 5.1, 4.0, and 4.2, respectively, struck the Livermore Valley. Two days later, a Richter magnitude 5.4 earthquake occurred, which had its epicenter about 4 miles northwest of the Lawrence Livermore National Laboratory (LLNL). Although no one at the Lab was seriously injured, these earthquakes caused considerable damage and disruption. Masonry and concrete structures cracked and broke, trailers shifted and fell off their pedestals, office ceilings and overhead lighting fell, and bookcases overturned. The Laboratory was suddenly immersed in a site-wide program of repairing earthquake-damaged facilities, and protecting our many employees and the surrounding community from future earthquakes. Over the past five years, LLNL has spent approximately $10 million on its earthquake restoration effort for repairs and upgrades. The discussion in this paper centers upon the earthquake damage that occurred, the clean-up and restoration efforts, the seismic review of LLNL facilities, our site-specific seismic design criteria, computer-floor upgrades, ceiling-system upgrades, unique building seismic upgrades, geologic and seismologic studies, and seismic instrumentation. 10 references

  9. Comparative Study on Code-based Linear Evaluation of an Existing RC Building Damaged during 1998 Adana-Ceyhan Earthquake

    International Nuclear Information System (INIS)

    Toprak, A. Emre; Guelay, F. Guelten; Ruge, Peter

    2008-01-01

    Determination of seismic performance of existing buildings has become one of the key concepts in structural analysis topics after recent earthquakes (i.e. Izmit and Duzce Earthquakes in 1999, Kobe Earthquake in 1995 and Northridge Earthquake in 1994). Considering the need for precise assessment tools to determine seismic performance level, most of earthquake hazardous countries try to include performance based assessment in their seismic codes. Recently, Turkish Earthquake Code 2007 (TEC'07), which was put into effect in March 2007, also introduced linear and non-linear assessment procedures to be applied prior to building retrofitting. In this paper, a comparative study is performed on the code-based seismic assessment of RC buildings with linear static methods of analysis, selecting an existing RC building. The basic principles dealing the procedure of seismic performance evaluations for existing RC buildings according to Eurocode 8 and TEC'07 will be outlined and compared. Then the procedure is applied to a real case study building is selected which is exposed to 1998 Adana-Ceyhan Earthquake in Turkey, the seismic action of Ms = 6.3 with a maximum ground acceleration of 0.28 g It is a six-storey RC residential building with a total of 14.65 m height, composed of orthogonal frames, symmetrical in y direction and it does not have any significant structural irregularities. The rectangular shaped planar dimensions are 16.40 mx7.80 m = 127.90 m 2 with five spans in x and two spans in y directions. It was reported that the building had been moderately damaged during the 1998 earthquake and retrofitting process was suggested by the authorities with adding shear-walls to the system. The computations show that the performing methods of analysis with linear approaches using either Eurocode 8 or TEC'07 independently produce similar performance levels of collapse for the critical storey of the structure. The computed base shear value according to Eurocode is much higher

  10. Comparative Study on Code-based Linear Evaluation of an Existing RC Building Damaged during 1998 Adana-Ceyhan Earthquake

    Science.gov (United States)

    Toprak, A. Emre; Gülay, F. Gülten; Ruge, Peter

    2008-07-01

    Determination of seismic performance of existing buildings has become one of the key concepts in structural analysis topics after recent earthquakes (i.e. Izmit and Duzce Earthquakes in 1999, Kobe Earthquake in 1995 and Northridge Earthquake in 1994). Considering the need for precise assessment tools to determine seismic performance level, most of earthquake hazardous countries try to include performance based assessment in their seismic codes. Recently, Turkish Earthquake Code 2007 (TEC'07), which was put into effect in March 2007, also introduced linear and non-linear assessment procedures to be applied prior to building retrofitting. In this paper, a comparative study is performed on the code-based seismic assessment of RC buildings with linear static methods of analysis, selecting an existing RC building. The basic principles dealing the procedure of seismic performance evaluations for existing RC buildings according to Eurocode 8 and TEC'07 will be outlined and compared. Then the procedure is applied to a real case study building is selected which is exposed to 1998 Adana-Ceyhan Earthquake in Turkey, the seismic action of Ms = 6.3 with a maximum ground acceleration of 0.28 g It is a six-storey RC residential building with a total of 14.65 m height, composed of orthogonal frames, symmetrical in y direction and it does not have any significant structural irregularities. The rectangular shaped planar dimensions are 16.40 m×7.80 m = 127.90 m2 with five spans in x and two spans in y directions. It was reported that the building had been moderately damaged during the 1998 earthquake and retrofitting process was suggested by the authorities with adding shear-walls to the system. The computations show that the performing methods of analysis with linear approaches using either Eurocode 8 or TEC'07 independently produce similar performance levels of collapse for the critical storey of the structure. The computed base shear value according to Eurocode is much higher

  11. Geomorphic legacy of medieval Himalayan earthquakes in the Pokhara Valley

    Science.gov (United States)

    Schwanghart, Wolfgang; Bernhardt, Anne; Stolle, Amelie; Hoelzmann, Philipp; Adhikari, Basanta R.; Andermann, Christoff; Tofelde, Stefanie; Merchel, Silke; Rugel, Georg; Fort, Monique; Korup, Oliver

    2016-04-01

    The Himalayas and their foreland belong to the world's most earthquake-prone regions. With millions of people at risk from severe ground shaking and associated damages, reliable data on the spatial and temporal occurrence of past major earthquakes is urgently needed to inform seismic risk analysis. Beyond the instrumental record such information has been largely based on historical accounts and trench studies. Written records provide evidence for damages and fatalities, yet are difficult to interpret when derived from the far-field. Trench studies, in turn, offer information on rupture histories, lengths and displacements along faults but involve high chronological uncertainties and fail to record earthquakes that do not rupture the surface. Thus, additional and independent information is required for developing reliable earthquake histories. Here, we present exceptionally well-dated evidence of catastrophic valley infill in the Pokhara Valley, Nepal. Bayesian calibration of radiocarbon dates from peat beds, plant macrofossils, and humic silts in fine-grained tributary sediments yields a robust age distribution that matches the timing of nearby M>8 earthquakes in ~1100, 1255, and 1344 AD. The upstream dip of tributary valley fills and X-ray fluorescence spectrometry of their provenance rule out local sediment sources. Instead, geomorphic and sedimentary evidence is consistent with catastrophic fluvial aggradation and debris flows that had plugged several tributaries with tens of meters of calcareous sediment from the Annapurna Massif >60 km away. The landscape-changing consequences of past large Himalayan earthquakes have so far been elusive. Catastrophic aggradation in the wake of two historically documented medieval earthquakes and one inferred from trench studies underscores that Himalayan valley fills should be considered as potential archives of past earthquakes. Such valley fills are pervasive in the Lesser Himalaya though high erosion rates reduce

  12. Earthquake Probability Assessment for the Active Faults in Central Taiwan: A Case Study

    Directory of Open Access Journals (Sweden)

    Yi-Rui Lee

    2016-06-01

    Full Text Available Frequent high seismic activities occur in Taiwan due to fast plate motions. According to the historical records the most destructive earthquakes in Taiwan were caused mainly by inland active faults. The Central Geological Survey (CGS of Taiwan has published active fault maps in Taiwan since 1998. There are 33 active faults noted in the 2012 active fault map. After the Chi-Chi earthquake, CGS launched a series of projects to investigate the details to better understand each active fault in Taiwan. This article collected this data to develop active fault parameters and referred to certain experiences from Japan and the United States to establish a methodology for earthquake probability assessment via active faults. We consider the active faults in Central Taiwan as a good example to present the earthquake probability assessment process and results. The appropriate “probability model” was used to estimate the conditional probability where M ≥ 6.5 and M ≥ 7.0 earthquakes. Our result shows that the highest earthquake probability for M ≥ 6.5 earthquake occurring in 30, 50, and 100 years in Central Taiwan is the Tachia-Changhua fault system. Conversely, the lowest earthquake probability is the Chelungpu fault. The goal of our research is to calculate the earthquake probability of the 33 active faults in Taiwan. The active fault parameters are important information that can be applied in the following seismic hazard analysis and seismic simulation.

  13. The GIS and analysis of earthquake damage distribution of the 1303 Hongtong M=8 earthquake

    Science.gov (United States)

    Gao, Meng-Tan; Jin, Xue-Shen; An, Wei-Ping; Lü, Xiao-Jian

    2004-07-01

    The geography information system of the 1303 Hongton M=8 earthquake has been established. Using the spatial analysis function of GIS, the spatial distribution characteristics of damage and isoseismal of the earthquake are studies. By comparing with the standard earthquake intensity attenuation relationship, the abnormal damage distribution of the earthquake is found, so the relationship of the abnormal distribution with tectonics, site condition and basin are analyzed. In this paper, the influence on the ground motion generated by earthquake source and the underground structures near source also are studied. The influence on seismic zonation, anti-earthquake design, earthquake prediction and earthquake emergency responding produced by the abnormal density distribution are discussed.

  14. Effect of Instrumentation Length and Instrumentation Systems: Hand Versus Rotary Files on Apical Crack Formation - An In vitro Study.

    Science.gov (United States)

    Devale, Madhuri R; Mahesh, M C; Bhandary, Shreetha

    2017-01-01

    Stresses generated during root canal instrumentation have been reported to cause apical cracks. The smaller, less pronounced defects like cracks can later propagate into vertical root fracture, when the tooth is subjected to repeated stresses from endodontic or restorative procedures. This study evaluated occurrence of apical cracks with stainless steel hand files, rotary NiTi RaCe and K3 files at two different instrumentation lengths. In the present in vitro study, 60 mandibular premolars were mounted in resin blocks with simulated periodontal ligament. Apical 3 mm of the root surfaces were exposed and stained using India ink. Preoperative images of root apices were obtained at 100x using stereomicroscope. The teeth were divided into six groups of 10 each. First two groups were instrumented with stainless steel files, next two groups with rotary NiTi RaCe files and the last two groups with rotary NiTi K3 files. The instrumentation was carried out till the apical foramen (Working Length-WL) and 1 mm short of the apical foramen (WL-1) with each file system. After root canal instrumentation, postoperative images of root apices were obtained. Preoperative and postoperative images were compared and the occurrence of cracks was recorded. Descriptive statistical analysis and Chi-square tests were used to analyze the results. Apical root cracks were seen in 30%, 35% and 20% of teeth instrumented with K-files, RaCe files and K3 files respectively. There was no statistical significance among three instrumentation systems in the formation of apical cracks (p=0.563). Apical cracks were seen in 40% and 20% of teeth instrumented with K-files; 60% and 10% of teeth with RaCe files and 40% and 0% of teeth with K3 files at WL and WL-1 respectively. For groups instrumented with hand files there was no statistical significance in number of cracks at WL and WL-1 (p=0.628). But for teeth instrumented with RaCe files and K3 files significantly more number of cracks were seen at WL than

  15. Effect of Instrumentation Length and Instrumentation Systems: Hand Versus Rotary Files on Apical Crack Formation – An In vitro Study

    Science.gov (United States)

    Mahesh, MC; Bhandary, Shreetha

    2017-01-01

    Introduction Stresses generated during root canal instrumentation have been reported to cause apical cracks. The smaller, less pronounced defects like cracks can later propagate into vertical root fracture, when the tooth is subjected to repeated stresses from endodontic or restorative procedures. Aim This study evaluated occurrence of apical cracks with stainless steel hand files, rotary NiTi RaCe and K3 files at two different instrumentation lengths. Materials and Methods In the present in vitro study, 60 mandibular premolars were mounted in resin blocks with simulated periodontal ligament. Apical 3 mm of the root surfaces were exposed and stained using India ink. Preoperative images of root apices were obtained at 100x using stereomicroscope. The teeth were divided into six groups of 10 each. First two groups were instrumented with stainless steel files, next two groups with rotary NiTi RaCe files and the last two groups with rotary NiTi K3 files. The instrumentation was carried out till the apical foramen (Working Length-WL) and 1 mm short of the apical foramen (WL-1) with each file system. After root canal instrumentation, postoperative images of root apices were obtained. Preoperative and postoperative images were compared and the occurrence of cracks was recorded. Descriptive statistical analysis and Chi-square tests were used to analyze the results. Results Apical root cracks were seen in 30%, 35% and 20% of teeth instrumented with K-files, RaCe files and K3 files respectively. There was no statistical significance among three instrumentation systems in the formation of apical cracks (p=0.563). Apical cracks were seen in 40% and 20% of teeth instrumented with K-files; 60% and 10% of teeth with RaCe files and 40% and 0% of teeth with K3 files at WL and WL-1 respectively. For groups instrumented with hand files there was no statistical significance in number of cracks at WL and WL-1 (p=0.628). But for teeth instrumented with RaCe files and K3 files

  16. Bridge seismic retrofit measures considering subduction zone earthquakes.

    Science.gov (United States)

    2015-07-01

    Over the years, earthquakes have exposed the vulnerability of reinforced concrete structures under : seismic loads. The recent occurrence of highly devastating earthquakes near instrumented regions, e.g. 2010 Maule, Chile : and 2011 Tohoku, Japan, ha...

  17. Tilt Precursors before Earthquakes on the San Andreas Fault, California.

    Science.gov (United States)

    Johnston, M J; Mortensen, C E

    1974-12-13

    An array of 14 biaxial shallow-borehole tiltmeters (at 1O(-7) radian sensitivity) has been installed along 85 kilometers of the San Andreas fault during the past year. Earthquake-related changes in tilt have been simultaneously observed on up to four independent instruments. At earthquake distances greater than 10 earthquake source dimensions, there are few clear indications of tilt change. For the four instruments with the longest records (> 10 months), 26 earthquakes have occurred since July 1973 with at least one instrument closer than 10 source dimensions and 8 earthquakes with more than one instrument within that distance. Precursors in tilt direction have been observed before more than 10 earthquakes or groups of earthquakes, and no similar effect has yet been seen without the occurrence of an earthquake.

  18. A view to the intermediate-depth Vrancea earthquake of May 30, 1990: Case study in NE Bulgaria

    International Nuclear Information System (INIS)

    Kouteva, M.; Paskaleva, I.; Panza, G.F.; Romanelli, F.

    2004-02-01

    A deterministic analytical procedure for ground motion modelling, combining both modal summation and mode coupling techniques has been implemented to obtain synthetic seismic signals at Russe, NE Bulgaria, due to one of the strongest Vrancea intermediate-depth earthquakes, which occurred during the last century, May 30, 1990. The frequency content of the synthetic signals in different frequency ranges, up to 1 and 2Hz, has been studied separately. The results of this study, i.e. time histories and related ground motions parameters, can be used for different earthquake engineering analyses, e.g. structural performance assessments. (author)

  19. Fault parameters and macroseismic observations of the May 10, 1997 Ardekul-Ghaen earthquake

    Science.gov (United States)

    Amini, H.; Zare, M.; Ansari, A.

    2018-01-01

    The Ardekul (Zirkuh) earthquake (May 10, 1997) is the largest recent earthquake that occurred in the Ardekul-Ghaen region of Eastern Iran. The greatest destruction was concentrated around Ardekul, Haji-Abad, Esfargh, Pishbar, Bashiran, Abiz-Qadim, and Fakhr-Abad (completely destroyed). The total surface fault rupture was about 125 km with the longest un-interrupted segment in the south of the region. The maximum horizontal and vertical displacements were reported in Korizan and Bohn-Abad with about 210 and 70 cm, respectively; moreover, other building damages and environmental effects were also reported for this earthquake. In this study, the intensity value XI on the European Macroseismic Scale (EMS) and Environmental Seismic Intensity (ESI) scale was selected for this earthquake according to the maximum effects on macroseismic data points affected by this earthquake. Then, according to its macroseismic data points of this earthquake and Boxer code, some macroseismic parameters including magnitude, location, source dimension, and orientation of this earthquake were also estimated at 7.3, 33.52° N-59.99° E, 75 km long and 21 km wide, and 152°, respectively. As the estimated macroseismic parameters are consistent with the instrumental ones (Global Centroid Moment Tensor (GCMT) location and magnitude equal 33.58° N-60.02° E, and 7.2, respectively), this method and dataset are suggested not only for other instrumental earthquakes, but also for historical events.

  20. Study of graphite sealing for the instrumentation feed through part

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Jintae; Ahn, Sungho; Joung, Changyoung; Kim, Kahye [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    Because highly pressurized (15.5 MPa) and highly heated (300 .deg. C) coolant is circulated through the test rig, it needs to seal out the instrumentation feed through part. In this case, general sealing method is brazing and several works have been carried out in nuclear fields. However, because high temperature is induced on the sealing plug and sheaths, it is easy to be broken due to oxidisation of the sheath during brazing process. In addition, because the brazing process is irreversible, if the brazing process fails, the whole inner assembly should be scrapped out. Another approach which uses graphite has been studied to seal out the instrumentation feed through part. In the study, graphite sealing is considered as a sealing method and the improvement of mechanical structure has been studied to improve the workability. To check the sealing performance of the instrumentation feed through part, a hydraulic pressure test and a helium leak test were carried out according to the ASME section III. The criterion of a hydraulic pressure test is 125% of the design pressure. In this study, because the design pressure of the pressure vessel is 17.5 MPa. the sealing criterion should be 21.9 MPa. Also, in a Helium leak test, the criterion is less than 5 Χ 10{sup -9} torr·liter/sec. At first, a Helium leak test was carried out. After eliminating Helium in the pressure vessel by evacuating the internal area of the pressure vessel up to 1 Χ 10{sup -3} torr using ASM 310, Helium detection test was carried out by spraying Helium gas at the top face of the top flange for 5 minutes. Fig. 4 shows the rate of Helium leakage is 2.4 Χ 10{sup -9} torr·liter/sec, and it satisfies the sealing performance criterion. A hydraulic pressure test was also carried out, and there was no leakage or pressure drop when the water in the pressure vessel is pressurized up to 22.5 MPa. The above test results show that graphite powder can seal out the instrumentation feed through part easily with

  1. Study of graphite sealing for the instrumentation feed through part

    International Nuclear Information System (INIS)

    Hong, Jintae; Ahn, Sungho; Joung, Changyoung; Kim, Kahye

    2013-01-01

    Because highly pressurized (15.5 MPa) and highly heated (300 .deg. C) coolant is circulated through the test rig, it needs to seal out the instrumentation feed through part. In this case, general sealing method is brazing and several works have been carried out in nuclear fields. However, because high temperature is induced on the sealing plug and sheaths, it is easy to be broken due to oxidisation of the sheath during brazing process. In addition, because the brazing process is irreversible, if the brazing process fails, the whole inner assembly should be scrapped out. Another approach which uses graphite has been studied to seal out the instrumentation feed through part. In the study, graphite sealing is considered as a sealing method and the improvement of mechanical structure has been studied to improve the workability. To check the sealing performance of the instrumentation feed through part, a hydraulic pressure test and a helium leak test were carried out according to the ASME section III. The criterion of a hydraulic pressure test is 125% of the design pressure. In this study, because the design pressure of the pressure vessel is 17.5 MPa. the sealing criterion should be 21.9 MPa. Also, in a Helium leak test, the criterion is less than 5 Χ 10 -9 torr·liter/sec. At first, a Helium leak test was carried out. After eliminating Helium in the pressure vessel by evacuating the internal area of the pressure vessel up to 1 Χ 10 -3 torr using ASM 310, Helium detection test was carried out by spraying Helium gas at the top face of the top flange for 5 minutes. Fig. 4 shows the rate of Helium leakage is 2.4 Χ 10 -9 torr·liter/sec, and it satisfies the sealing performance criterion. A hydraulic pressure test was also carried out, and there was no leakage or pressure drop when the water in the pressure vessel is pressurized up to 22.5 MPa. The above test results show that graphite powder can seal out the instrumentation feed through part easily with the improved

  2. Dosimetry, instrumentation and exposure chambers for dc magnetic field studies

    International Nuclear Information System (INIS)

    Tenforde, T.S.

    1979-03-01

    The principal objective of this report is to describe in detail an exposure chamber that was developed at the Lawrence Berkeley Laboratory for automated, noninvasive studies of rodent physiology during exposure to high DC magnetic fields. A second objective is to discuss some of the unique instrumentation problems that must be overcome in order to record bioelectric signals from laboratory animals in the presence of a magnetic field. Finally, a description will be given of the various dosimetry techniques that can be employed for quantitation of magnetic field strength

  3. Social Networking of Instrumentation - a Case Study in Telematics

    OpenAIRE

    ROBU, D.; SANDU, F.; PETREUS, D.; NEDELCU, A.; BALICA, A.

    2014-01-01

    The research work contributes to the design and implementation of the communication part for integrating remote instruments and drives via social networks (SN) into instrumentation communities. It is used the virtual instrumentation (VI) to manage objects that tweet on popular SN platforms applying the concept of the Internet of Things (IoT). Local and remote resource aggregation is based on National Instruments (NI) data acquisition and distribution hardware in a NI software ...

  4. A Study on Earthquake-Related Geoid Deformation at Beijing-Tangshan and West Yunnan During 1985-1998

    Science.gov (United States)

    Li, Z.

    2006-05-01

    Based on the determination of the non-tidal variations in the deflection of the vertical (or PlumbLine Variations, PLVs) at Beijing astronomical observatory, the work has been extended into a determination of the PLV array within a 4 x 1 (degree) area at Beijing-Tangshan. By repeated observations of the gravimetric network, 46 batches of this PLV array, and consequently the relative geoid deformation (RGD), of the area during 1987- 1998 have been determined. Together with the 23 earthquakes (Mb > 4.0) in the area during the same period, a comparison is done between an earthquake event and the related RGD. Similar study has also been carried out for the case in West Yunnan, where 32 batches of repeated gravimetric observations of the network there during 1985-1998 have been performed from which the 32 PLV array, as well as the corresponding RGD, of a 2 x 2 (dergee) area has been calculated. A comparison is also done at West Yunnan between an earthquake event and its related RGD. It is interesting to see that the earthquake and the RGD measured are related. It appears that there is usually a detectable RGD nearby well before an earthquake, but a contrary RGD afterwards. The study provides us a new approach in geodesy on the RGD determination, as well as a new measurable phenomenon in an earthquake event at Beijing-Tangshan and West Yunnan. The study also provides us evidence in which the existence of the PLVs, as well as the corresponding RGD, at Beijing- Tangshan and West Yunnan becomes more conclusive. Their potential usage in geodesy and seismology, as well as in other related sciences, is now expected.

  5. DEVELOPING OF INDIVIDUAL INSTRUMENT PERFORMANCE ANXIETY SCALE: VALIDITY - RELIABILITY STUDY

    Directory of Open Access Journals (Sweden)

    Esra DALKIRAN

    2014-07-01

    Full Text Available The purpose of this study is to develop a scale unique to our culture, concerning  individual instrument performance anxiety of the students  who are getting instrument training  in the Department of Music Education. In the study, the descriptive research model is used and qualitative research techniques are utilized. The study population consists of the students attending the 23 universities which has Music Education Department. The sample of the study consists of 438 girls and 312 boys, totally 750 students  who are studying in the Department of Music Education of randomly selected 10 universities. As a result of the explanatory and confirmatory factor analyses that were performed, a one-dimensional structure consisting of 14 items was obtained. Also, t-scores and  the coefficient scores of total item correlation concerning the distinguishing power of the items, the difference in the scores of the set of lower and upper 27% was calculated, and it was observed that the items are distinguishing as a result of both analyses. Of the scale, Cronbach's alpha coefficient of internal consistency was calculated as .94, and test-retest reliability coefficient was calculated as .93. As a result, a valid and reliable assessment and evaluation instrument that measures the exam performance anxiety of the students studying in the Department of Music Education, has been developed.Extended AbstractsIntroductionAnxiety is a universal phenomenon which people experience once or a few times during lives. It was accepted as concern for the future or as an unpleasant emotional experience regarding probable hitches of the events (Di Tomasso & Gosch, 2002.In general, the occasions on which negative feelings are experienced cause anxiety to arise (Baltaş and Baltaş, 2000. People also feel anxious in dangerous situations. Anxiety may lead a person to be creative, while it may have hindering characteristics. Anxiety is that an individual considers him

  6. The numerical simulation study of the dynamic evolutionary processes in an earthquake cycle on the Longmen Shan Fault

    Science.gov (United States)

    Tao, Wei; Shen, Zheng-Kang; Zhang, Yong

    2016-04-01

    The Longmen Shan, located in the conjunction of the eastern margin the Tibet plateau and Sichuan basin, is a typical area for studying the deformation pattern of the Tibet plateau. Following the 2008 Mw 7.9 Wenchuan earthquake (WE) rupturing the Longmen Shan Fault (LSF), a great deal of observations and studies on geology, geophysics, and geodesy have been carried out for this region, with results published successively in recent years. Using the 2D viscoelastic finite element model, introducing the rate-state friction law to the fault, this thesis makes modeling of the earthquake recurrence process and the dynamic evolutionary processes in an earthquake cycle of 10 thousand years. By analyzing the displacement, velocity, stresses, strain energy and strain energy increment fields, this work obtains the following conclusions: (1) The maximum coseismic displacement on the fault is on the surface, and the damage on the hanging wall is much more serious than that on the foot wall of the fault. If the detachment layer is absent, the coseismic displacement would be smaller and the relative displacement between the hanging wall and foot wall would also be smaller. (2) In every stage of the earthquake cycle, the velocities (especially the vertical velocities) on the hanging wall of the fault are larger than that on the food wall, and the values and the distribution patterns of the velocity fields are similar. While in the locking stage prior to the earthquake, the velocities in crust and the relative velocities between hanging wall and foot wall decrease. For the model without the detachment layer, the velocities in crust in the post-seismic stage is much larger than those in other stages. (3) The maximum principle stress and the maximum shear stress concentrate around the joint of the fault and detachment layer, therefore the earthquake would nucleate and start here. (4) The strain density distribution patterns in stages of the earthquake cycle are similar. There are two

  7. Case Study of Local Damage Indicators for a 2-Bay, 6-Storey RC-Frame subject to Earthquakes

    DEFF Research Database (Denmark)

    Skjærbæk, P. S.; Nielsen, Søren R. K.; Kirkegaard, Poul Henning

    1997-01-01

    A simulation study of a 2-bay, 6storey model test RC-frame(scale 1:5) subject to earthquakes is considered in this paper. Based on measured (simulated) storey accelerations and ground surface accelerations several indices for the storey damage, including interstorey drift, flexural damage ratios......, normalized cumulative dissipated energy, Park and Ang's indicator, a low-cycle fatigue damage index and a recently proposed local softening damage index estimated from time-varying eigenfrequencies are used to evaluate the damage state of the structure after the earthquake. Storey displacements are obtained...

  8. Case Study of Local Damage Indicators for a 2-Bay, 6-Storey RC-Frame subject to Earthquakes

    DEFF Research Database (Denmark)

    Skjærbæk, P. S.; Nielsen, Søren R. K.; Kirkegaard, Poul Henning

    A simulation study of a 2-bay, 6storey model test RC-frame(scale 1:5) subject to earthquakes is considered in this paper. Based on measured (simulated) storey accelerations and ground surface accelerations several indices for the storey damage, including interstorey drift, flexural damage ratios......, normalized cumulative dissipated energy, Park and Ang's indicator, a low-cycle fatigue damage index and a recently proposed local softening damage index estimated from time-varying eigenfrequencies are used to evaluate the damage state of the structure after the earthquake. Storey displacements are obtained...

  9. Mental health problems among children one-year after Sichuan earthquake in China: a follow-up study.

    Directory of Open Access Journals (Sweden)

    Mingxin Liu

    Full Text Available BACKGROUND: On May 12, 2008, a destructive earthquake registering 8.0 on the Richter scale struck Sichuan Province, southwest China. Beichuan County was the epicenter which was one of the areas nearly completely destroyed by the earthquake. In Beichuan, about 15000 people died and 3000 people were missing. Specially, the earthquake took 1587 students' and 214 teachers' lives from the elementary and middle schools there. The main purpose of the study was to provide a better understanding of mental health problems and associated risk factors among children after earthquake. METHOD: Three hundred and thirty grades 3-5 children completed the questionnaire of disaster -related experience and the Trauma Symptom Checklist for Children-Alternate Version (TSCC-A. The first survey was carried out six months after the earthquake, and the second one was carried out six months later. The measurements and methodology applied in the two sessions were identical. RESULTS: The prevalence rates of the problems at two time-points were 23.3% and 22.7% for anxiety, 14.5% and 16.1% for depression, and 11.2% and 13.4% for PTSD, respectively. Among demographic variables, no significant age difference existed, while it was found that 6 months after the earthquake, symptoms of anxiety, depression and PTSD were significantly more common among students in grades 4 and 5 than those in grade 3, Initial exposure to death, bereavement and extreme fear were significant predictive factors for the occurrence of anxiety, depression and PTSD. CONCLUSIONS: Findings of this study suggest that posttraumatic mental health problems after natural disaster in children may have reached epidemic proportions and remain high for a long period. Psychologist and social workers should pay more attention to children who experienced more traumatic stresses and provide appropriate mental health interventions. Implications and limitations of these findings were discussed.

  10. A study on generation of simulated earthquake ground motion for seismic design of nuclear power plant

    International Nuclear Information System (INIS)

    Ichiki, Tadaharu; Matsumoto, Takuji; Kitada, Yoshio; Osaki, Yorihiko; Kanda, Jun; Masao, Toru.

    1985-01-01

    The aseismatic design of nuclear power generation facilities carried out in Japan at present must conform to the ''Guideline for aseismatic design examination regarding power reactor facilities'' decided by the Atomic Energy Commission in 1978. In this guideline, the earthquake motion used for the analysis of dynamic earthquake response is to be given in the form of the magnitude determined on the basis of the investigation of historical earthquakes and active faults around construction sites and the response spectra corresponding to the distance from epicenters. Accordingly when the analysis of dynamic earthquake response is actually carried out, the simulated earthquake motion made in conformity with these set up response spectra is used as the input earthquake motion for the design. For the purpose of establishing the techniques making simulated earthquake motion which is more appropriate and rational from engineering viewpoint, the research was carried out, and the results are summarized in this paper. The techniques for making simulated earthquake motion, the response of buildings and the response spectra of floors are described. (Kako, I.)

  11. High frequency, high amplitude and low energy earthquake study of nuclear power plants

    International Nuclear Information System (INIS)

    Bernero, R.M.; Lee, A.J.H.; Sobel, P.A.

    1988-01-01

    Nuclear power plants are designed for a seismic input spectrum based on U.S. acceleration time histories. However, data recorded near several earthquakes, mostly in the Eastern U.S., are richer in high frequency energy. This paper focuses on the evaluation of one of these events, i.e., the 1986 Ohio earthquake approximately 10 miles from the Perry nuclear power plant. The Perry Seismic Category I structures were reanalyzed using the in-structure recorded earthquake motions. The calculated in-structure response spectra and recorded response spectra have the same general trends, which shows the buildings are capable of responding to high frequency earthquake motion. Dynamic stresses calculated using the Ohio earthquake recorded motions are substantially lower than the design stresses. The seismic qualification of a wide sample of equipment was reassessed using the Ohio earthquake recorded motions and the margins were found to be larger than one. The 1986 Ohio earthquake was also shown to possess much lower energy content and ductility demand than the design spectra. For the Perry case, the seismic design was shown to have adequate safety margins to accommodate the 1986 Ohio earthquake, even though the design spectra were exceeded at about 20 Hz. The NRC is evaluating the need to generically modify design spectra in light of the recent high frequency recordings. (orig.)

  12. Determination of Love- and Rayleigh-Wave Magnitudes for Earthquakes and Explosions and Other Studies

    Science.gov (United States)

    2012-12-30

    09-C-0012 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) Jessie L. Bonner, Anastasia Stroujkova, Dale Anderson, Jonathan...AND RAYLEIGH-WAVE MAGNITUDES FOR EARTHQUAKES AND EXPLOSIONS Jessie L. Bonner, Anastasia Stroujkova, and Dale Anderson INTRODUCTION Since...MAXIMUM LIKELIHOOD ESTIMATION: APPLICATION TO MIDDLE EAST EARTHQUAKE DATA Anastasia Stroujkova and Jessie Bonner Weston Geophysical Corporation

  13. Study of changes in the lineament structure, caused by earthquakes in South America by applying the lineament analysis to the Aster (Terra) satellite data

    Science.gov (United States)

    Arellano-Baeza, A. A.; Zverev, A. T.; Malinnikov, V. A.

    The region between Southern Peru and Northern Chile is one of the most seismically and volcanically active regions in South America. This is caused by a constant subduction of the South American Plate, converging with the Nazca Plate in the extreme North of Chile. We used the 15 and 30 m resolution satellite images, provided by the ASTER (VNIR and SWIR) instrument onboard the Terra satellite to study changes in the geological faults close to earthquake epicenters in southern Peru. Visible and infrared spectral bands were analysed using “The Lineament Extraction and Stripes Statistic Analysis” (LESSA) software package to examine changes in the lineament features and stripe density fields caused by seismic activity. We used the satellite images 128 and 48 days before and 73 days after a 5.2 Richter scale magnitude earthquake. The fact that the seasonal variations in the South of Peru and North of Chile are very small, and the vegetation is very limited, allowed us to establish substantial changes in the lineament and the stripe density field features. We develop a methodology that allows to evaluate the seismic risk in this region for the future.

  14. Sun, Moon and Earthquakes

    Science.gov (United States)

    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.

  15. Training With Curved Laparoscopic Instruments in Single-Port Setting Improves Performance Using Straight Instruments: A Prospective Randomized Simulation Study.

    Science.gov (United States)

    Lukovich, Peter; Sionov, Valery Ben; Kakucs, Timea

    2016-01-01

    Lately single-port surgery is becoming a widespread procedure, but it is more difficult than conventional laparoscopy owing to the lack of triangulation. Although, these operations are also possible with standard laparoscopic instruments, curved instruments are being developed. The aims of the study were to identify the effect of training on a box trainer in single-port setting on the quality of acquired skills, and transferred with the straight and curved instruments for the basic laparoscopic tasks, and highlight the importance of a special laparoscopic training curriculum. A prospective study on a box trainer in single-port setting was conducted using 2 groups. Each group performed 2 tasks on the box trainer in single-port setting. Group-S used conventional straight laparoscopic instruments, and Group-C used curved laparoscopic instruments. Learning curves were obtained by daily measurements recorded in 7-day sessions. On the last day, the 2 groups changed instruments between each other. 1st Department of Surgery, Semmelweis University of Medicine from Budapest, Hungary, a university teaching hospital. In all, 20 fifth-year medical students were randomized into 2 groups. None of them had any laparoscopic or endoscopic experience. Participation was voluntary. Although Group-S performed all tasks significantly faster than Group-C on the first day, the difference proved to be nonsignificant on the last day. All participants achieved significantly shorter task completion time on the last day than on the first day, regardless of the instrument they used. Group-S showed improvement of 63.5%, and Group-C 69.0% improvement by the end of the session. After swapping the instruments, Group-S reached significantly higher task completion time with curved instruments, whereas Group-C showed further progression of 8.9% with straight instruments. Training with curved instruments in a single-port setting allows for a better acquisition of skills in a shorter period. For this

  16. Integrated Earthquake Risk Assessment in the Kathmandu Valley - A Case Study

    Science.gov (United States)

    Schaper, Julia; Anhorn, Johannes; Khazai, Bijan; Nüsser, Marcus

    2013-04-01

    Rapid urban growth is a process which can be observed in cities worldwide. Managing these growing urban areas has become a major challenge for both governing bodies and citizens. Situated not only in a highly earthquake and landslide-prone area, but comprising also the cultural and political capital of Nepal, the fast expanding Kathmandu Valley in the Himalayan region is of particular interest. Vulnerability assessment has been an important tool for spatial planning in this already densely populated area. The magnitude 8.4 earthquake of Bihar in 1934 cost 8600 Nepalis their lives, destroyed 20% of the Kathmandu building stock and heavily damaged another 40%. Since then, Kathmandu has grown into a hub with over a million inhabitants. Rapid infrastructure and population growth aggravate the vulnerability conditions, particularly in the core area of Metropolitan Kathmandu. We propose an integrative framework for vulnerability and risk in Kathmandu Valley. In order to move towards a more systemic and integrated approach, we focus on interactions between natural hazards, physically engineered systems and society. High resolution satellite images are used to identify structural vulnerability of the building stock within the study area. Using object-based image analysis, the spatial dynamics of urban growth are assessed and validated using field data. Complementing this is the analysis of socio-economic attributes gained from databases and field surveys. An indicator-based vulnerability and resilience index will be operationalized using multi-attribute value theory and statistical methods such as principal component analysis. The results allow for a socio-economic comparison of places and their relative potential for harm and loss. The objective in this task is to better understand the interactions between nature and society, engineered systems and built environments through the development of an interdisciplinary framework on systemic seismic risk and vulnerability. Data

  17. Big Data, the perfect instrument to study today's consumer behavior

    Directory of Open Access Journals (Sweden)

    Cristina STOICESCU

    2016-01-01

    Full Text Available Consumer behavior study is a new, interdisciplinary and emerging science, developed in the 1960s. Its main sources of information come from economics, psychology, sociology, anthropology and artificial intelligence. If a century ago, most people were living in small towns, with limited possibilities to leave their community, and few ways to satisfy their needs, now, due to the accelerated evolution of technology and the radical change of life style, consumers begin to have increasingly diverse needs. At the same time the instruments used to study their behavior have evolved, and today databases are included in consumer behavior research. Throughout time many models were developed, first in order to analyze, and later in order to predict the consumer behavior. As a result, the concept of Big Data developed, and by applying it now, companies are trying to understand and predict the behavior of their consumers.

  18. Lithospheric Structure, Crustal Kinematics, and Earthquakes in North China: An Integrated Study

    Science.gov (United States)

    Liu, M.; Yang, Y.; Sandvol, E.; Chen, Y.; Wang, L.; Zhou, S.; Shen, Z.; Wang, Q.

    2007-12-01

    The North China block (NCB) is geologically part of the Archaean Sino-Korean craton. But unusual for a craton, it was thermally rejuvenated since late Mesozoic, and experienced widespread extension and volcanism through much of the Cenozoic. Today, the NCB is characterized by strong internal deformation and seismicity, including the 1976 Tangshan earthquake that killed ~250,000 people. We have started a multidisciplinary study to image the lithospheric and upper mantle structure using seismological methods, to delineate crustal kinematics and deformation via studies of neotectonics and space geodesy, and to investigate the driving forces, the stress states and evolution, and seismicity using geodynamic modeling. Both seismic imaging and GPS results indicate that the Ordos plateau, which is the western part of the NCB and a relic of the Sino-Korean craton, has been encroached around its southern margins by mantle flow and thus is experiencing active cratonic destruction. Some of the mantle flow may be driven by the Indo-Asian collision, although the cause of the broad mantle upwelling responsible for the Mesozoic thinning of the NCB lithosphere remains uncertain. At present, crustal deformation in the NCB is largely driven by gravitational spreading of the expanding Tibetan Plateau. Internal deformation within the NCB is further facilitated by the particular tectonic boundary conditions around the NCB, and the large lateral contrasts of lithospheric strength and rheology. Based on the crustal kinematics and lithospheric structure, we have developed a preliminary geodynamic model for stress states and strain energy in the crust of the NCB. The predicted long-term strain energy distribution is comparable with the spatial pattern of seismic energy release in the past 2000 years. We are exploring the cause of the spatiotemporal occurrence of large earthquakes in the NCB, especially the apparent migration of seismicity from the Weihe-Shanxi grabens around the Ordos to

  19. Depressive symptoms and associated psychosocial factors among adolescent survivors 30 months after 2008 Wenchuan earthquake: A follow-up study

    Directory of Open Access Journals (Sweden)

    Xuliang eShi

    2016-03-01

    Full Text Available AbstractPurpose: This study longitudinally investigated the changes of depressive symptoms among adolescent survivors over two years and a half after the 2008 Wenchuan earthquake in China, as well as the predictive effects of demographic characteristics, earthquake exposure, negative life events, social support and dispositional resilience on the risk of depressive symptoms at two time points after the earthquake.Methods: Participants were 1573 adolescent survivors (720 males and 853 females, mean age at initial survey =15 ± 1.26, whose depressive symptoms were assessed at 6 months (T6m and 30 months (T30m post-earthquake. Data on demographics, earthquake exposure and dispositional resilience were collected at T6m. Negative life events and social support were measured at T6m and 24 months (T24m post-earthquake.Results: The prevalence rates of probable depression, 27.5% at T6m and 27.2% at T30m, maintained relatively stable over time. Female gender was related with higher risk of depressive symptoms at both T6m and T30m, while being only-child could only predict higher risk of depressive symptoms at T30m. Negative life events and social support at T6m, as well as earthquake exposure, were concurrently associated with increased risk of depressive symptoms at T6m, but not associated with the risk of depressive symptoms at T30m, while negative life events and social support at T24m could predict depressive symptoms at T30m, all of which suggested that these variables may have strong but short-term effect on adolescents’ depressive symptoms post-earthquake. Besides, dispositional resilience was evidenced as a relatively stable negative predictor for depressive symptoms.Conclusions: These findings could inform mental health professionals regarding how to screen adolescent survivors at high risk for depression, so as to provide them with timely and appropriate mental health services based on the identified risk and protective factors for depressive

  20. Graduate studies in instrumentation at the University of Provence

    International Nuclear Information System (INIS)

    Carette, M.; Reynard, C.; Claire, N.; Deschaintres, J. L.; Felts, B.; Lyoussi, A.; Andre, J.; Bertin, D.

    2009-01-01

    The University of Provence instrumentation department offers a high level of graduate and post graduate engineering programs. Its mission is to form technician experts and engineers with a deep knowledge in their discipline: metrology, instrumentation, tests, Research and Development, automatism and industrial process control. The specialty of master on test facilities instrumentation has been developed in collaboration with the French Atomic Energy Commission (CEA) since 2004. This curriculum offers now a specialization in nuclear detection and nuclear instrumentation. More than 80% of the graduates formed by block-release training of master find a job within 6 months

  1. Investigation of the ULF electromagnetic phenomena related to earthquakes. Contemporary achievements and the perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Kopytenko, Y.; Ismagilov, V. [SPbF Izmiran, St. Petersbourg (Russian Federation); Hayakawa, M [The University of Electro-Communications, Chofu, Tokyo (Japan); Smirnova, N.; Troyan, V. [St. Petersbourg Univ., St Petersbourg (Russian Federation). Inst. of Physics; Peterson, T. [TFPLAB, Cleveland, OH (United States)

    2001-04-01

    The results of ULF electromagnetic signal observations in seismoactive regions prior to earthquakes are presented and discussed. The new differential measurement technique developed in SPbF IZMIRAN for location of the ULF emission sources of space and lithosphere origin is described. The MVC-2DS geohphysical instrumentation is introduced as a promising tool for registration of ULF signals related to earthquakes (both seismic and electromagnetic ones). Methods are proposed for ULF data processing to investigate the preparation processes in the earthquake source regions and to distinguish seismogenic signals. on the background of space pulsations. Some examples of application of those methods for study of the earthquake precursory signatures are presented. Perspectives of seismo-electromagnetic tomography experiments in seismoactive regions, using MVC-2DS technique, are discussed in relation to the development of earthquake prediction methods.

  2. Crustal stress evolution of last 700 years in North China and earthquake occurrences

    Science.gov (United States)

    Wan, Y.; Shen, Z.; Gan, W.; Li, T.; Zeng, Y.

    2004-12-01

    We simulate the evolution process of cumulative Coulomb failure stress change (Δ CFS) in North China since 1303, manifested by secular tectonic stress loading and occurrence of large earthquakes. Secular tectonic stress loading is averaged from crustal strain rates derived from GPS. Fault rupture parameters of historical earthquakes are estimated as follows: the earthquake rupture length and the amount of slip are derived based on their statistical relationships with the earthquake intensity distribution and magnitude, calibrated using parameters of instrumental measured contemporary earthquakes. The earthquake rake angle is derived based on geologically determined fault setting parameters and seismically estimated orientation of regional tectonic stresses. Assuming a layered visco-elastic medium, we calculate stress evolution resulted from secular tectonic loading and coseismic and postseismic deformation. 49 M¡Y6.5 earthquakes occurred in North China since 1303. Statistics shows that 39 out of the 48 subsequent events were triggered by positive Δ CFS, yielding a triggering rate of 81.3%. The triggering rate for M¡Y5 earthquakes after the 1976 Tangshan earthquake is 82.1%. The triggering rate is up to 90% if corrections are made for some aftershocks which were wrongly identified as occurred in stress shadow zones because of errors in parameter estimates of historical earthquakes. Our study shows very high correlation between positive Δ CFS and earthquake occurrences. Relatively high Δ CFS in North China at present time is concentrated around the Bohai Sea, the west segment of the Northern Qinling fault, western end of the Zhangjiakou-Bohai seismic zone, and the Taiyuan basin in Shanxi rift zone, suggesting relatively higher earthquake potential in these areas.

  3. Earthquake Catalogue of the Caucasus

    Science.gov (United States)

    Godoladze, T.; Gok, R.; Tvaradze, N.; Tumanova, N.; Gunia, I.; Onur, T.

    2016-12-01

    The Caucasus has a documented historical catalog stretching back to the beginning of the Christian era. Most of the largest historical earthquakes prior to the 19th century are assumed to have occurred on active faults of the Greater Caucasus. Important earthquakes include the Samtskhe earthquake of 1283 (Ms˜7.0, Io=9); Lechkhumi-Svaneti earthquake of 1350 (Ms˜7.0, Io=9); and the Alaverdi earthquake of 1742 (Ms˜6.8, Io=9). Two significant historical earthquakes that may have occurred within the Javakheti plateau in the Lesser Caucasus are the Tmogvi earthquake of 1088 (Ms˜6.5, Io=9) and the Akhalkalaki earthquake of 1899 (Ms˜6.3, Io =8-9). Large earthquakes that occurred in the Caucasus within the period of instrumental observation are: Gori 1920; Tabatskuri 1940; Chkhalta 1963; Racha earthquake of 1991 (Ms=7.0), is the largest event ever recorded in the region; Barisakho earthquake of 1992 (M=6.5); Spitak earthquake of 1988 (Ms=6.9, 100 km south of Tbilisi), which killed over 50,000 people in Armenia. Recently, permanent broadband stations have been deployed across the region as part of the various national networks (Georgia (˜25 stations), Azerbaijan (˜35 stations), Armenia (˜14 stations)). The data from the last 10 years of observation provides an opportunity to perform modern, fundamental scientific investigations. In order to improve seismic data quality a catalog of all instrumentally recorded earthquakes has been compiled by the IES (Institute of Earth Sciences/NSMC, Ilia State University) in the framework of regional joint project (Armenia, Azerbaijan, Georgia, Turkey, USA) "Probabilistic Seismic Hazard Assessment (PSHA) in the Caucasus. The catalogue consists of more then 80,000 events. First arrivals of each earthquake of Mw>=4.0 have been carefully examined. To reduce calculation errors, we corrected arrivals from the seismic records. We improved locations of the events and recalculate Moment magnitudes in order to obtain unified magnitude

  4. Simple instrument for biochemical studies of the living human brain

    International Nuclear Information System (INIS)

    Bice, A.N.; Wagner, H.N. Jr.; Lee, M.C.; Frost, J.J.

    1986-01-01

    A simple, relatively inexpensive radiation detection system was developed for measurement of positron-emitting receptor-binding drugs in the human brain. This high-efficiency coincidence counting system requires that only a few hundred microcuries of labeled drug be administered to the subject, thereby allowing for multiple studies without an excessive radiation dose. Measurement of the binding of [ 11 C]-carfentanil, a high-affinity synthetic opiate, to opiate receptors in the presence and in the absence of a competitive opiate antagonist exemplifies the use of this system for estimating different degrees of receptor binding of drugs in the human brain. The instrument has also been used for measurement of the transport into the brain of other positron-emitting radiotracers, such as large neutral amino acids

  5. Studying local earthquakes in the northern Fennoscandian Shield using the data of the POLENET/LAPNET temporary array

    Science.gov (United States)

    Usoltseva, O. A.; Kozlovskaya, E. G.

    2015-12-01

    Earthquakes within areas inside continental plates are still not completely understood and the progress in understanding intraplate seismicity is slow due to 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 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 temporary seismic array during the International Polar Year 2007-2009. We relocate the seismic events by the program HYPOELLIPS 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 selected region inside the study area and show that the velocity heterogeneities in the upper crust correlate well with known tectonic units. We compare 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 Archean and Paleoproterozoic. On the contrary, they correlate well with the post-glacial faults located in the area of the Baltic-Bothnia Megashear (BBMS). Hypocentres of local events have depths down to 30 km. We also obtain focal mechanisms of two selected events with good data quality. Both focal mechanisms are of strike-slip type in which shift prevails over uplift. Our results demonstrate that Baltic-Bothnia Megashear is an important large-scale, reactivated tectonic structure that has to be taken into account in estimating seismic hazard in northern Fennoscandia.

  6. From Multi-Sensors Observations Towards Cross-Disciplinary Study of Pre-Earthquake Signals. What have We Learned from the Tohoku Earthquake?

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Papadopoulos, G.; Kunitsyn, V.; Nesterov, I.; Hayakawa, M.; Mogi, K.; Hattori, K.; Kafatos, M.; Taylor, P.

    2012-01-01

    The lessons we have learned from the Great Tohoku EQ (Japan, 2011) how this knowledge will affect our future observation and analysis is the main focus of this presentation.We present multi-sensors observations and multidisciplinary research in our investigation of phenomena preceding major earthquakes. These observations revealed the existence of atmospheric and ionospheric phenomena occurring prior to theM9.0 Tohoku earthquake of March 11, 2011, which indicates s new evidence of a distinct coupling between the lithosphere and atmosphere/ionosphere, as related to underlying tectonic activity. Similar results have been reported before the catastrophic events in Chile (M8.8, 2010), Italy (M6.3, 2009) and Sumatra (M9.3, 2004). For the Tohoku earthquake, our analysis shows a synergy between several independent observations characterizing the state of the lithosphere /atmosphere coupling several days before the onset of the earthquakes, namely: (i) Foreshock sequence change (rate, space and time); (ii) Outgoing Long wave Radiation (OLR) measured at the top of the atmosphere; and (iii) Anomalous variations of ionospheric parameters revealed by multi-sensors observations. We are presenting a cross-disciplinary analysis of the observed pre-earthquake anomalies and will discuss current research in the detection of these signals in Japan. We expect that our analysis will shed light on the underlying physics of pre-earthquake signals associated with some of the largest earthquake events

  7. Studying geodesy and earthquake hazard in and around the New Madrid Seismic Zone

    Science.gov (United States)

    Boyd, Oliver Salz; Magistrale, Harold

    2011-01-01

    Workshop on New Madrid Geodesy and the Challenges of Understanding Intraplate Earthquakes; Norwood, Massachusetts, 4 March 2011 Twenty-six researchers gathered for a workshop sponsored by the U.S. Geological Survey (USGS) and FM Global to discuss geodesy in and around the New Madrid seismic zone (NMSZ) and its relation to earthquake hazards. The group addressed the challenge of reconciling current geodetic measurements, which show low present-day surface strain rates, with paleoseismic evidence of recent, relatively frequent, major earthquakes in the region. The workshop presentations and conclusions will be available in a forthcoming USGS open-file report (http://pubs.usgs.gov).

  8. Effects of three-dimensional crustal structure and smoothing constraint on earthquake slip inversions: Case study of the Mw6.3 2009 L'Aquila earthquake

    KAUST Repository

    Gallovič, František; Imperatori, Walter; Mai, Paul Martin

    2015-01-01

    Earthquake slip inversions aiming to retrieve kinematic rupture characteristics typically assume 1-D velocity models and a flat Earth surface. However, heterogeneous nature of the crust and presence of rough topography lead to seismic scattering and other wave propagation phenomena, introducing complex 3-D effects on ground motions. Here we investigate how the use of imprecise Green's functions - achieved by including 3-D velocity perturbations and topography - affect slip-inversion results. We create sets of synthetic seismograms, including 3-D heterogeneous Earth structure and topography, and then invert these synthetics using Green's functions computed for a horizontally layered 1-D Earth model. We apply a linear inversion, regularized by smoothing and positivity constraint, and examine in detail how smoothing effects perturb the solution. Among others, our tests and resolution analyses demonstrate how imprecise Green's functions introduce artificial slip rate multiples especially at shallow depths and that the timing of the peak slip rate is hardly affected by the chosen smoothing. The investigation is extended to recordings of the 2009 Mw6.3 L'Aquila earthquake, considering both strong motion and high-rate GPS stations. We interpret the inversion results taking into account the lessons learned from the synthetic tests. The retrieved slip model resembles previously published solutions using geodetic data, showing a large-slip asperity southeast of the hypocenter. In agreement with other studies, we find evidence for fast but subshear rupture propagation in updip direction, followed by a delayed propagation along strike. We conjecture that rupture was partially inhibited by a deep localized velocity-strengthening patch that subsequently experienced afterslip.

  9. Effects of three-dimensional crustal structure and smoothing constraint on earthquake slip inversions: Case study of the Mw6.3 2009 L'Aquila earthquake

    KAUST Repository

    Gallovič, František

    2015-01-01

    Earthquake slip inversions aiming to retrieve kinematic rupture characteristics typically assume 1-D velocity models and a flat Earth surface. However, heterogeneous nature of the crust and presence of rough topography lead to seismic scattering and other wave propagation phenomena, introducing complex 3-D effects on ground motions. Here we investigate how the use of imprecise Green\\'s functions - achieved by including 3-D velocity perturbations and topography - affect slip-inversion results. We create sets of synthetic seismograms, including 3-D heterogeneous Earth structure and topography, and then invert these synthetics using Green\\'s functions computed for a horizontally layered 1-D Earth model. We apply a linear inversion, regularized by smoothing and positivity constraint, and examine in detail how smoothing effects perturb the solution. Among others, our tests and resolution analyses demonstrate how imprecise Green\\'s functions introduce artificial slip rate multiples especially at shallow depths and that the timing of the peak slip rate is hardly affected by the chosen smoothing. The investigation is extended to recordings of the 2009 Mw6.3 L\\'Aquila earthquake, considering both strong motion and high-rate GPS stations. We interpret the inversion results taking into account the lessons learned from the synthetic tests. The retrieved slip model resembles previously published solutions using geodetic data, showing a large-slip asperity southeast of the hypocenter. In agreement with other studies, we find evidence for fast but subshear rupture propagation in updip direction, followed by a delayed propagation along strike. We conjecture that rupture was partially inhibited by a deep localized velocity-strengthening patch that subsequently experienced afterslip.

  10. Physical function, pain, quality of life and life satisfaction of amputees from the 2008 Sichuan earthquake: A prospective cohort study.

    Science.gov (United States)

    Li, Ling; Reinhardt, Jan D; Zhang, Xia; Pennycott, Andrew; Zhao, Zhengen; Zeng, Xianmen; Li, Jianan

    2015-05-01

    To examine the development and determinants of long-term outcomes for earthquake victims with amputations, including physical function, pain, quality of life and life satisfaction. Prospective cohort study with 2-3 measurement points. A total of 72 people who underwent amputations following the 2008 Sichuan Earthquake and resided in Mianzhu County, Sichuan Province, China were enrolled in the study. Of these, 27 people were lost to follow-up. Data on pain (visual analogue scale) and physical function (Barthel Index) were collected at 3 measurement points (2009, 2010 and 2012), and data on quality of life (Medical Outcomes Short-Form 36) and life satisfaction (Life Satisfaction Questionnaire-11) were collected at 2 measurement points (2010 and 2012). Data were analysed with mixed effects regression. Pain severity declined significantly and physical function increased by 2012. Quality of life and life satisfaction remained relatively stable between 2010 and 2012, while quality of life was significantly lower than reference values from the general population. Illiteracy and lower extremity amputations were associated with lower quality of life and life satisfaction in several domains. While amputees' functioning and pain were improved over time, quality of life and life satisfaction did not change. Illiterate earthquake survivors and those with lower extremity amputations are at particular risk of low quality of life and life satisfaction, and may require additional attention in future earthquake rehabilitation programs.

  11. Pre-earthquake multiparameter analysis of the 2016 Amatrice-Norcia (Central Italy) seismic sequence: a case study for the application of the SAFE project concepts

    Science.gov (United States)

    De Santis, A.

    2017-12-01

    The SAFE (Swarm for Earthquake study) project (funded by European Space Agency in the framework "STSE Swarm+Innovation", 2014-2016) aimed at applying the new approach of geosystemics to the analysis of Swarm satellite (ESA) electromagnetic data for investigating the preparatory phase of earthquakes. We present in this talk the case study of the most recent seismic sequence in Italy. First a M6 earthquake on 24 August 2016 and then a M6.5 earthquake on 30 October 2016 shocked almost in the same region of Central Italy causing about 300 deaths in total (mostly on 24 August), with a revival of other significant seismicity on January 2017. Analysing both geophysical and climatological satellite and ground data preceding the major earthquakes of the sequence we present results that confirm a complex solid earth-atmosphere coupling in the preparation phase of the whole sequence.

  12. A statistical study on the effect of earthquakes on the ionosphere, based on the subionospheric LF propagation data in Japan

    Directory of Open Access Journals (Sweden)

    S. Maekawa

    2006-09-01

    Full Text Available A superimposed epoch analysis has been undertaken, in order to find the correlation of the ionospheric perturbations with seismic activity. We take the wave path from the Japanese LF transmitter (frequency=40 kHz and an observing station of Kochi (wave path length of 770 km, and a much longer period (of five years than before, is considered. This subionospheric LF propagation can be called "an integrated measurement" in the sense that any earthquakes in the LF sensitive area just around the great-circle path can influence the observed LF signals, so that we define the "effective magnitude" (Meff by integrating the total energy from different earthquakes in the sensitive area on a current day and by converting it back into magnitude. A superimposed epoch analysis for the effective magnitude greater than 6.0 has yielded that the ionosphere is definitely disturbed in terms of both amplitude and dispersion, and that these perturbations tend to take place prior to an earthquake. The statistical z-test has also been performed, which has indicated that the amplitude is definitely depleted 2–6 days before the earthquake day and also that the dispersion is very much enhanced during the same period. This statistical study has given strong support to the existence of seismo-ionospheric perturbations for high seismic activity.

  13. Probabilistic Tsunami Hazard Analysis of the Pacific Coast of Mexico: Case Study Based on the 1995 Colima Earthquake Tsunami

    Directory of Open Access Journals (Sweden)

    Nobuhito Mori

    2017-06-01

    Full Text Available This study develops a novel computational framework to carry out probabilistic tsunami hazard assessment for the Pacific coast of Mexico. The new approach enables the consideration of stochastic tsunami source scenarios having variable fault geometry and heterogeneous slip that are constrained by an extensive database of rupture models for historical earthquakes around the world. The assessment focuses upon the 1995 Jalisco–Colima Earthquake Tsunami from a retrospective viewpoint. Numerous source scenarios of large subduction earthquakes are generated to assess the sensitivity and variability of tsunami inundation characteristics of the target region. Analyses of nine slip models along the Mexican Pacific coast are performed, and statistical characteristics of slips (e.g., coherent structures of slip spectra are estimated. The source variability allows exploring a wide range of tsunami scenarios for a moment magnitude (Mw 8 subduction earthquake in the Mexican Pacific region to conduct thorough sensitivity analyses and to quantify the tsunami height variability. The numerical results indicate a strong sensitivity of maximum tsunami height to major slip locations in the source and indicate major uncertainty at the first peak of tsunami waves.

  14. Study of the performance of diagnostic radiology instruments during calibration

    International Nuclear Information System (INIS)

    Freitas, Rodrigo N. de; Vivolo, Vitor; Potiens, Maria da Penha A.

    2008-01-01

    Full text: The instruments used in diagnostic radiology measurements represent 8 % of the tested instruments by the calibration laboratory of IPEN annually (approximately 1600 in 2007). Considering that the calibration of this kind of instrument is performed biannually it is possible to conclude that almost 300 instruments are being used to measure the air kerma in diagnostic radiology clinics to determine the in beam values (in front of the patient), attenuated measurements (behind the patient) and scattered radiation. This work presents the results of the calibration of the instruments used in mammography, computed tomography, dental and conventional diagnostic radiology dosimetry, performed during the period of 2005 to 2007. Their performances during the calibrations measurements were evaluated. Although at the calibration laboratory there are three available series of radiation quality to this type of calibration (RQR, N and M, according to standards IEC 61267 and ISO 4037-1.), the applications can be assorted (general radiology, computed tomography, mammography, radiation protection and fluoroscopy). Depending on its design and behaviour , one kind of instrument can be used for one or more type of applications. The instruments normally used for diagnostic radiology measurements are ionization chambers with volumes varying from 3 to 1800 cm 3 , and can be cylindrical, spherical or plane parallel plates kind. They usually are sensitive to photon particles, with energies greater than 15 keV and can be used up to 1200 keV. In this work they were tested in X radiation fields from 25 to 150 kV, in specific qualities depending on the utilization of the instrument. The calibration results of 390 instruments received from 2005 to 2007 were analyzed. About 20 instruments were not able to be calibrated due to bad functioning. The calibration coefficients obtained were between 0.88 and 1.24. The uncertainties were always less than ± 3.6% to instruments used in scattered

  15. Application of Incremental Dynamic Analysis (IDA) Method for Studying the Dynamic Behavior of Structures During Earthquakes

    OpenAIRE

    Javanpour, M.; Zarfam, P.

    2017-01-01

    Prediction of existing buildings’ vulnerability by future earthquakes is one of the most essential topics in structural engineering. Modeling steel structures is a giant step in determining the damage caused by the earthquake, as such structures are increasingly being used in constructions. Hence, two same-order steel structures with two types of structural systems were selected (coaxial moment frames and moment frame). In most cases, a specific structure needs to satisfy several functional l...

  16. X-ray diffraction study on the evaluation of the damage of steel structures subjected to earthquake

    International Nuclear Information System (INIS)

    Kaneta, Kiyoshi; Nishizawa, Hidekazu; Koshika, Norihide.

    1985-01-01

    The purpose of this study is to investigate the behavior of steel structures subjected to a strong earthquake and to evaluate the damage from a microscopic point of view. For this purpose, the authors have adopted two kinds of research techniques. The first is the ''ON-LINE EARTHQUAKE RESPONSE SIMULATION SYSTEM (ON-LINE SIMULATION SYSTEM)'', which is composed of an electro-hydrauric testing machine controled by a computer and a full scale specimen. Since a term of restoring force in the equation of motion is to be substituted by the actual reaction of a specimen under test, we can obtain the non-linear response of structure without any assumption about the hysteretic characteristics. Based on this method, the dynamic behavior of simple steel structures subjected to an intense earthquakes were simulated. The second technique is the ''X-RAY DIFFRACTION METHOD''. Although this method is usually regarded an experimental technique particular to the material science, we have realized the good applicability for the study of structural engineering. Because X-ray diffraction method is advantageous in investigating the microscopic behavior of steel member such as the plastic deformation and the low cycle fatigue. From the view point stated above, we have adopted this method for the evaluation of low cycle fatigue damage of steel member subjected to an earthquake. The experiment has been performed by radiating the X-ray at several stages of the ON-LINE SIMULATION. As has been expected, the X-ray diffraction patterns have changed in a regular manner depending on the degree of fatigue damage, and the results have shown a good possibility that the X-ray diffraction approach can offer a powerful tool for the detection of the earthquake damage of steel members. (author)

  17. A randomised controlled pilot study: the effectiveness of narrative exposure therapy with adult survivors of the Sichuan earthquake

    Directory of Open Access Journals (Sweden)

    Zang Yinyin

    2013-01-01

    Full Text Available Abstract Background Post-Traumatic Stress Disorder (PTSD is a common psychological reaction after large-scale natural disasters. Given the number of people involved and shortage of resources in any major disaster, brief, pragmatic and easily trainable interventions are needed. The aim of this study is to evaluate the efficacy of Narrative Exposure Therapy (NET as a short-term treatment for PTSD using Chinese earthquake survivors. Methods A randomized waiting-list control pilot study was conducted between December 2009 and March 2010, at the site of the Sichuan earthquake in Beichuan County, China. Adult participants with newly diagnosed Post Traumatic Stress Disorder (PTSD were randomly allocated to Narrative Exposure Therapy (NET or a Waiting-List (WL condition. The latter received NET treatment after a two-week waiting period. To compare the effectiveness of NET in traumatised earthquake survivors, both groups were assessed on PTSD symptoms, general mental health, anxiety and depression, social support, coping style and posttraumatic change before and after treatment and two months post treatment. Results Adult participants (n=22 were randomly allocated to receive NET (n=11 or WL (n=11. Twenty two participants (11 in NET group, 11 in WL were included in the analysis of primary outcomes. Compared with WL, NET showed significant reductions in PTSD symptoms, anxiety and depression, general mental stress and increased posttraumatic growth. The WL group later showed similar improvements after treatment. These changes remained stable for a two-month follow-up. Measures of social support and coping showed no stable effects. Conclusions NET is effective in treating post-earthquake traumatic symptoms in adult Chinese earthquake survivors. The findings help advance current knowledge in the management of PTSD after natural disasters and inform future research. Larger sample sizes are needed to extend the present findings. Trial registration Chinese

  18. Suicide risk among young children after the Great East Japan Earthquake: A follow-up study.

    Science.gov (United States)

    Fujiwara, Takeo; Yagi, Junko; Homma, Hiroaki; Mashiko, Hirobumi; Nagao, Keizo; Okuyama, Makiko

    2017-07-01

    On 11 March 2011, the Great East Japan Earthquake and subsequent tsunami hit East Japan. We aim to investigate the impact of trauma experiences related to the earthquake on suicide risk among young children, stratified by child sex. Participants at baseline were children who were exposed to the 2011 disaster at preschool age (affected area, n=198; unaffected area, n=82, total n=280). From July 2013 to May 2014, suicide risk was assessed using the Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) in a follow-up interview conducted by a child psychiatrist or psychologist (N=210, follow-up rate: 75%). Among young girls in the affected area, 12 out of 65 (18.5%) showed suicidal ideation, which is significantly higher than girls in the unaffected area (4.7%, p for chi-square=0.036). In the multivariate model adjusted for potential confounders and mediators, the odds ratio for 4 or more trauma experiences related to the earthquake was 5.74 (95% confidence interval: 0.83-39.6, p=0.076) compared to no trauma experience related to the earthquake. Among young boys, trauma exposure was not associated with suicidal ideation. Our findings showed that young girls who experienced earthquake-related trauma at preschool age had a higher suicidal ideation 3 years after the earthquake. Copyright © 2017. Published by Elsevier B.V.

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

    Science.gov (United States)

    Jackson, D. D.

    2017-12-01

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

  20. Neutron scattering and diffraction instrument for structural study on biology in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Niimura, Nobuo [Japan Atomic Energy Research Inst., Ibaraki-ken (Japan)

    1994-12-31

    Neutron scattering and diffraction instruments in Japan which can be used for structural studies in biology are briefly introduced. Main specifications and general layouts of the instruments are shown.

  1. Preparation of earthquake-triggered landslide inventory maps using remote sensing and GIS technologies: Principles and case studies

    Directory of Open Access Journals (Sweden)

    Chong Xu

    2015-11-01

    Full Text Available Inventory maps of earthquake-triggered landslides can be constructed using several methods, which are often subject to obvious differences due to lack of commonly accepted criteria or principles. To solve this problem, the author describes the principles for preparing inventory maps of earthquake-triggered landslides, focusing on varied methods and their criteria. The principles include the following key points: all landslides should be mapped as long as they can be recognized from images; both the boundary and source area position of landslides should be mapped; spatial distribution pattern of earthquake-triggered landslides should be continuous; complex landslides should be divided into distinct groups; three types of errors such as precision of the location and boundary of landslides, false positive errors, and false negative errors of earthquake-triggered landslide inventories should be controlled and reduced; and inventories of co-seismic landslides should be constructed by the visual interpretation method rather than automatic extraction of satellite images or/and aerial photographs. In addition, selection of remote sensing images and creation of landslides attribute database are also discussed in this paper. Then the author applies these principles to produce inventory maps of four events: the 12 May 2008 Wenchuan, China Mw 7.9, 14 April 2010 Yushu, China Mw 6.9, 12 January 2010 Haiti Mw 7.0, and 2007 Aysén Fjord, Chile Mw 6.2. The results show obvious differences in comparison with previous studies by other researchers, which again attest to the necessity of establishment of unified principles for preparation of inventory maps of earthquake-triggered landslides.

  2. Earthquake hazard assessment and small earthquakes

    International Nuclear Information System (INIS)

    Reiter, L.

    1987-01-01

    The significance of small earthquakes and their treatment in nuclear power plant seismic hazard assessment is an issue which has received increased attention over the past few years. In probabilistic studies, sensitivity studies showed that the choice of the lower bound magnitude used in hazard calculations can have a larger than expected effect on the calculated hazard. Of particular interest is the fact that some of the difference in seismic hazard calculations between the Lawrence Livermore National Laboratory (LLNL) and Electric Power Research Institute (EPRI) studies can be attributed to this choice. The LLNL study assumed a lower bound magnitude of 3.75 while the EPRI study assumed a lower bound magnitude of 5.0. The magnitudes used were assumed to be body wave magnitudes or their equivalents. In deterministic studies recent ground motion recordings of small to moderate earthquakes at or near nuclear power plants have shown that the high frequencies of design response spectra may be exceeded. These exceedances became important issues in the licensing of the Summer and Perry nuclear power plants. At various times in the past particular concerns have been raised with respect to the hazard and damage potential of small to moderate earthquakes occurring at very shallow depths. In this paper a closer look is taken at these issues. Emphasis is given to the impact of lower bound magnitude on probabilistic hazard calculations and the historical record of damage from small to moderate earthquakes. Limited recommendations are made as to how these issues should be viewed

  3. Impact of the Northridge earthquake on the mental health of veterans: results from a panel study.

    Science.gov (United States)

    Dobalian, Aram; Stein, Judith A; Heslin, Kevin C; Riopelle, Deborah; Venkatesh, Brinda; Lanto, Andrew B; Simon, Barbara; Yano, Elizabeth M; Rubenstein, Lisa V

    2011-09-01

    The 1994 earthquake that struck Northridge, California, led to the closure of the Veterans Health Administration Medical Center at Sepulveda. This article examines the earthquake's impact on the mental health of an existing cohort of veterans who had previously used the Sepulveda Veterans Health Administration Medical Center. From 1 to 3 months after the disaster, trained interviewers made repeated attempts to contact participants by telephone to administer a repeated measures follow-up design survey based on a survey that had been done preearthquake. Postearthquake data were obtained on 1144 of 1800 (64%) male veterans for whom there were previous data. We tested a predictive latent variable path model of the relations between sociodemographic characteristics, predisaster physical and emotional health measures, and postdisaster emotional health and perceived earthquake impact. Perceived earthquake impact was predicted by predisaster emotional distress, functional limitations, and number of health conditions. Postdisaster emotional distress was predicted by preexisting emotional distress and earthquake impact. The regression coefficient from earthquake impact to postearthquake emotional distress was larger than that of the stability coefficient from preearthquake emotional distress. Postearthquake emotional distress also was affected indirectly by preearthquake emotional distress, health conditions, younger age, and lower socioeconomic status. The postdisaster emotional health of veterans who experienced greater earthquake impact would have likely benefited from postdisaster intervention, regardless of their predisaster emotional health. Younger veterans and veterans with generally poor physical and emotional health were more vulnerable to greater postearthquake emotional distress. Veterans of lower socioeconomic status were disproportionately likely to experience more effects of the disaster because they had more predisaster emotional distress, more functional

  4. Earthquake data base for Romania

    International Nuclear Information System (INIS)

    Rizescu, M.; Ghica, D.; Grecu, B.; Popa, M.; Borcia, I. S.

    2002-01-01

    A new earthquake database for Romania is being constructed, comprising complete earthquake information and being up-to-date, user-friendly and rapidly accessible. One main component of the database consists from the catalog of earthquakes occurred in Romania since 984 up to present. The catalog contains information related to locations and other source parameters, when available, and links to waveforms of important earthquakes. The other very important component is the 'strong motion database', developed for strong intermediate-depth Vrancea earthquakes where instrumental data were recorded. Different parameters to characterize strong motion properties as: effective peak acceleration, effective peak velocity, corner periods T c and T d , global response spectrum based intensities were computed and recorded into this database. Also, information on the recording seismic stations as: maps giving their positioning, photographs of the instruments and site conditions ('free-field or on buildings) are included. By the huge volume and quality of gathered data, also by its friendly user interface, the Romania earthquake data base provides a very useful tool for geosciences and civil engineering in their effort towards reducing seismic risk in Romania. (authors)

  5. Instrumental neutron activation analysis of tree rings for dendrochemical studies

    International Nuclear Information System (INIS)

    Schaumloffel, J.C.; Filby, R.H.

    1996-01-01

    Instrumental neutron activation analysis (INAA) was employed to determine zinc, cadmium and potassium concentrations in the growth rings of ponderosa pine (Pinus ponderosa Dougl.) trees growing along the shores of Lake Roosevelt in Washington State, U.S.A. where mineral processing activities have resulted in high burdens of zinc and cadmium in the lake sediments. The tree growing along the contaminated waterway display elevated concentrations of zinc in its growth rings relative to a tree growing along an uncontaminated tributary of Lake Roosevelt. Cadmium concentrations in the growth rings from both sites are similar from 1988 to 1993. Water quality data indicate an increased concentration of cadmium in the lake from 1984 to 1988. The increased concentrations of cadmium in the lake water were reflected in apparent increases in concentrations of cadmium in individual rings of the tree sampled at the contaminated site. This suggests that translocation of cadmium in the sapwood of heartwood-forming species does not occur in the short term, and thus may not be a limiting factor in using trees as environmental monitors for cadmium. In addition, five-year tree ring segments were analyzed and subsequently reanalyzed as individual single-year ring segments. The analytical data obtained for the pooled individual rings are essentially the same as for the five-year segments, demonstrating the utility of NAA for dendrochemical studies. (author). 24 refs., 5 figs., 2 tabs

  6. Method to deterministically study photonic nanostructures in different experimental instruments.

    Science.gov (United States)

    Husken, B H; Woldering, L A; Blum, C; Vos, W L

    2009-01-01

    We describe an experimental method to recover a single, deterministically fabricated nanostructure in various experimental instruments without the use of artificially fabricated markers, with the aim to study photonic structures. Therefore, a detailed map of the spatial surroundings of the nanostructure is made during the fabrication of the structure. These maps are made using a series of micrographs with successively decreasing magnifications. The graphs reveal intrinsic and characteristic geometric features that can subsequently be used in different setups to act as markers. As an illustration, we probe surface cavities with radii of 65 nm on a silica opal photonic crystal with various setups: a focused ion beam workstation; a scanning electron microscope (SEM); a wide field optical microscope and a confocal microscope. We use cross-correlation techniques to recover a small area imaged with the SEM in a large area photographed with the optical microscope, which provides a possible avenue to automatic searching. We show how both structural and optical reflectivity data can be obtained from one and the same nanostructure. Since our approach does not use artificial grids or markers, it is of particular interest for samples whose structure is not known a priori, like samples created solely by self-assembly. In addition, our method is not restricted to conducting samples.

  7. Racial identity invalidation with multiracial individuals: An instrument development study.

    Science.gov (United States)

    Franco, Marisa G; O'Brien, Karen M

    2018-01-01

    Racial identity invalidation, others' denial of an individual's racial identity, is a salient racial stressor with harmful effects on the mental health and well-being of Multiracial individuals. The purpose of this study was to create a psychometrically sound measure to assess racial identity invalidation for use with Multiracial individuals (N = 497). The present sample was mostly female (75%) with a mean age of 26.52 years (SD = 9.60). The most common racial backgrounds represented were Asian/White (33.4%) and Black/White (23.7%). Participants completed several online measures via Qualtrics. Exploratory factor analyses revealed 3 racial identity invalidation factors: behavior invalidation, phenotype invalidation, and identity incongruent discrimination. A confirmatory factor analysis provided support for the initial factor structure. Alternative model testing indicated that the bifactor model was superior to the 3-factor model. Thus, a total score and/or 3 subscale scores can be used when administering this instrument. Support was found for the reliability and validity of the total scale and subscales. In line with the minority stress theory, challenges with racial identity mediated relationships between racial identity invalidation and mental health and well-being outcomes. The findings highlight the different dimensions of racial identity invalidation and indicate their negative associations with connectedness and psychological well-being. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  8. Predictors of quality of life and depression in older people living in temporary houses 13 months after the Wenchuan earthquake in western China: A cross-sectional study.

    Science.gov (United States)

    Xie, Xia; Chen, Yanling; Chen, Hong; Au, Alma; Guo, Hongxia

    2017-06-01

    In this study, we explored the predictors of quality of life and depressive features in older people living in temporary housing 13 months after the Wenchuan earthquake in western China. Anonymous data were collected via questionnaires in a cross-sectional survey of 189 older people living in temporary housing 13 months after the earthquake. To explore the predictors of the outcomes of interest, Pearson correlation and multiple linear regression analysis were used. The results indicated that interests/hobbies, subjective support, and family function were positive predictors of quality of life, whereas instrumental activities of daily living and depressive symptoms were its negative predictors. In addition, we found that a higher level of instrumental activities of daily living predicted a greater likelihood of depression. These results suggested that developing strategies to decrease the instrumental activities of daily living score of these people helps improve their quality of life and depression. To enhance the quality of life of these individuals, healthcare providers should also focus on developing their interests/hobbies and provide them with adequate social support, especially subjective support. © 2017 John Wiley & Sons Australia, Ltd.

  9. A Feasibility Study for Earthquake Early Warning in a School in Southern Italy

    Science.gov (United States)

    Emolo, A.; Martino, C.; Picozzi, M.; Zollo, A.; Elia, L.; Festa, G.; Colombelli, S.; Caruso, A.; Brondi, P.; Miranda, N.

    2015-12-01

    We present the results of a feasibility study on the application of earthquake early-warning procedures in the high school ITIS E. Majorana, Somma Vesuviana, Naples, located about 80 km far from the seismogenic Irpinia region. The study was performed in the framework of the European REAKT project. The school was equipped with an EEWS composed of: a small seismic network of accelerometers, the PRESToPlus software platform, and an actuator, named Sentinel. The Sentinel is made up of low-cost hardware (i.e., Arduino®) programmed to accomplish three main tasks: 1) listen and interpret messages delivered by the EEW system PRESToPlus on the ground motion severity expected at the target site; 2) provides different warnings as alert levels by the control of different hardware (i.e., alarm bells, emergency lights, and so on); 3) declare the end of the most threatening condition, which will assist the emergency coordinator starting the evacuation plan defined by the current legislation. The Sentinel was developed within REAKT in close collaboration with the students and the teachers of the school. The EEW system and the Sentinel were successfully tested during some blind drills performed during normal school activities.

  10. Post-Disaster Business Recovery and Sustainable Development: A Study of 2008 Wenchuan Earthquake

    Directory of Open Access Journals (Sweden)

    Lifang Huang

    2018-02-01

    Full Text Available Business sectors are essential for community prosperity, and thus it is important to investigate the recovery of businesses after disasters. However, current studies on business recovery after natural disasters are limited, particularly a lack of empirical observations in developing countries. Our observations of the patterns and transformations of small businesses in the recovery process after the 2008 Wenchuan earthquake in China can bridge this gap and provide a valuable contribution to academia. We conducted research through a four-year longitudinal study to track small business recovery in Beichuan County since 2014. Field observations, repeat photography, and semi-structured interviews were used to collect data. The operating status, business type, and spatiotemporal changes of small businesses in the new business district, Banaqia, were demonstrated. Overall, less than 50% of the planned shops were occupied and in operation, and this figure keeps declining from 2014 to 2017. Catering, garments, and souvenirs are the primary business types, but they show individual patterns in terms of sustainable development and spatial configuration. The results help to inform the development of recovery policies following disasters in developing countries.

  11. An Investigation on Borojerd as a Vulnerable Area against Earthquake, a Case Study of Borojerd Houses

    Directory of Open Access Journals (Sweden)

    Seyed Jalalaldin Faraji

    2014-12-01

    Full Text Available - Iran is one of the countries which is always struck by quake and its location on HimalayanAlpine belt has enhanced this condition such that in the previous century it has experienced more than 130 quakes with magnitude 7.5 in Richter scale. This phenomenon is not destructive in itself but lack of structures’ tolerance against forces caused by quake devastates and ruins them for different reasons. Iran is one of the ten natural disaster-prone countries and it is known as the sixth earthquake stricken country which causes high death toll. Based on this, urban security has great importance in this land. In this regard, this study has used a survey and analytical method based on qualitative and quantitative characteristics of Borojerd houses with the aim of identifying the amount of vulnerability using national statistics and random sampling. The results of this study indicated that seismic risk is high in Borojerd and confirmed low level of material resistance and high density of families in houses and lack of facilities and important services like hospitals, fire-fighting and rescue centers in critical situation.

  12. Clinical Studies on Treatment of Earthquake-Caused Posttraumatic Stress Disorder Using Electroacupuncture

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2012-01-01

    Full Text Available The objective of this study was to assess the efficacy and safety of electroacupuncture in 138 patients with earthquake-caused PTSD using Randomized Controlled Trials (RCTs. 138 cases enrolled were randomly assigned to an electro-acupuncture group and a paroxetine group. The electro-acupuncture group was treated by scalp electro-acupuncture on Baihui (GV 20, Sishencong (EX-HN 1, Shenting (GV 24, and Fengchi (GB 20, and the paroxetine group was treated with simple oral administration of paroxetine. The efficacy and safety of the electro-acupuncture on treatment of 69 PTSD patients were evaluated using Clinician-Administered PTSD Scale (CAPS, Hamilton Depression Scale (HAMD, Hamilton Anxiety Scale (HAMA, and Treatment Emergent Symptom Scale (TESS according to clinical data. The total scores of CAPS, HAMD, and HAMA in the two groups after treatment showed significant efficacy compared to those before treatment. The comparison of reduction in the scores of CAPS, HAMD, and HAMA between the two groups suggested that the efficacy in the treated group was better than that in the paroxetine group. The present study suggested that the electro-acupuncture and paroxetine groups have significant changes in test PTSD, but the electro-acupuncture 2 group was more significant.

  13. Remotely Triggered Earthquakes Recorded by EarthScope's Transportable Array and Regional Seismic Networks: A Case Study Of Four Large Earthquakes

    Science.gov (United States)

    Velasco, A. A.; Cerda, I.; Linville, L.; Kilb, D. L.; Pankow, K. L.

    2013-05-01

    Changes in field stress required to trigger earthquakes have been classified in two basic ways: static and dynamic triggering. Static triggering occurs when an earthquake that releases accumulated strain along a fault stress loads a nearby fault. Dynamic triggering occurs when an earthquake is induced by the passing of seismic waves from a large mainshock located at least two or more fault lengths from the epicenter of the main shock. We investigate details of dynamic triggering using data collected from EarthScope's USArray and regional seismic networks located in the United States. Triggered events are identified using an optimized automated detector based on the ratio of short term to long term average (Antelope software). Following the automated processing, the flagged waveforms are individually analyzed, in both the time and frequency domains, to determine if the increased detection rates correspond to local earthquakes (i.e., potentially remotely triggered aftershocks). Here, we show results using this automated schema applied to data from four large, but characteristically different, earthquakes -- Chile (Mw 8.8 2010), Tokoku-Oki (Mw 9.0 2011), Baja California (Mw 7.2 2010) and Wells Nevada (Mw 6.0 2008). For each of our four mainshocks, the number of detections within the 10 hour time windows span a large range (1 to over 200) and statistically >20% of the waveforms show evidence of anomalous signals following the mainshock. The results will help provide for a better understanding of the physical mechanisms involved in dynamic earthquake triggering and will help identify zones in the continental U.S. that may be more susceptible to dynamic earthquake triggering.

  14. Tectonics earthquake distribution pattern analysis based focal mechanisms (Case study Sulawesi Island, 1993–2012)

    International Nuclear Information System (INIS)

    Ismullah M, Muh. Fawzy; Lantu,; Aswad, Sabrianto; Massinai, Muh. Altin

    2015-01-01

    Indonesia is the meeting zone between three world main plates: Eurasian Plate, Pacific Plate, and Indo – Australia Plate. Therefore, Indonesia has a high seismicity degree. Sulawesi is one of whose high seismicity level. The earthquake centre lies in fault zone so the earthquake data gives tectonic visualization in a certain place. This research purpose is to identify Sulawesi tectonic model by using earthquake data from 1993 to 2012. Data used in this research is the earthquake data which consist of: the origin time, the epicenter coordinate, the depth, the magnitude and the fault parameter (strike, dip and slip). The result of research shows that there are a lot of active structures as a reason of the earthquake in Sulawesi. The active structures are Walannae Fault, Lawanopo Fault, Matano Fault, Palu – Koro Fault, Batui Fault and Moluccas Sea Double Subduction. The focal mechanism also shows that Walannae Fault, Batui Fault and Moluccas Sea Double Subduction are kind of reverse fault. While Lawanopo Fault, Matano Fault and Palu – Koro Fault are kind of strike slip fault

  15. Tectonics earthquake distribution pattern analysis based focal mechanisms (Case study Sulawesi Island, 1993–2012)

    Energy Technology Data Exchange (ETDEWEB)

    Ismullah M, Muh. Fawzy, E-mail: mallaniung@gmail.com [Master Program Geophysical Engineering, Faculty of Mining and Petroleum Engineering (FTTM), Bandung Institute of Technology (ITB), Jl. Ganesha no. 10, Bandung, 40116, Jawa Barat (Indonesia); Lantu,; Aswad, Sabrianto; Massinai, Muh. Altin [Geophysics Program Study, Faculty of Mathematics and Natural Sciences, Hasanuddin University (UNHAS), Jl. PerintisKemerdekaan Km. 10, Makassar, 90245, Sulawesi Selatan (Indonesia)

    2015-04-24

    Indonesia is the meeting zone between three world main plates: Eurasian Plate, Pacific Plate, and Indo – Australia Plate. Therefore, Indonesia has a high seismicity degree. Sulawesi is one of whose high seismicity level. The earthquake centre lies in fault zone so the earthquake data gives tectonic visualization in a certain place. This research purpose is to identify Sulawesi tectonic model by using earthquake data from 1993 to 2012. Data used in this research is the earthquake data which consist of: the origin time, the epicenter coordinate, the depth, the magnitude and the fault parameter (strike, dip and slip). The result of research shows that there are a lot of active structures as a reason of the earthquake in Sulawesi. The active structures are Walannae Fault, Lawanopo Fault, Matano Fault, Palu – Koro Fault, Batui Fault and Moluccas Sea Double Subduction. The focal mechanism also shows that Walannae Fault, Batui Fault and Moluccas Sea Double Subduction are kind of reverse fault. While Lawanopo Fault, Matano Fault and Palu – Koro Fault are kind of strike slip fault.

  16. Charles Darwin's earthquake reports

    Science.gov (United States)

    Galiev, Shamil

    2010-05-01

    problems which began to discuss only during the last time. Earthquakes often precede volcanic eruptions. According to Darwin, the earthquake-induced shock may be a common mechanism of the simultaneous eruptions of the volcanoes separated by long distances. In particular, Darwin wrote that ‘… the elevation of many hundred square miles of territory near Concepcion is part of the same phenomenon, with that splashing up, if I may so call it, of volcanic matter through the orifices in the Cordillera at the moment of the shock;…'. According to Darwin the crust is a system where fractured zones, and zones of seismic and volcanic activities interact. Darwin formulated the task of considering together the processes studied now as seismology and volcanology. However the difficulties are such that the study of interactions between earthquakes and volcanoes began only recently and his works on this had relatively little impact on the development of geosciences. In this report, we discuss how the latest data on seismic and volcanic events support the Darwin's observations and ideas about the 1835 Chilean earthquake. The material from researchspace. auckland. ac. nz/handle/2292/4474 is used. We show how modern mechanical tests from impact engineering and simple experiments with weakly-cohesive materials also support his observations and ideas. On the other hand, we developed the mathematical theory of the earthquake-induced catastrophic wave phenomena. This theory allow to explain the most important aspects the Darwin's earthquake reports. This is achieved through the simplification of fundamental governing equations of considering problems to strongly-nonlinear wave equations. Solutions of these equations are constructed with the help of analytic and numerical techniques. The solutions can model different strongly-nonlinear wave phenomena which generate in a variety of physical context. A comparison with relevant experimental observations is also presented.

  17. Geophysical Anomalies and Earthquake Prediction

    Science.gov (United States)

    Jackson, D. D.

    2008-12-01

    some understanding of their sources and the physical properties of the crust, which also vary from place to place and time to time. Anomalies are not necessarily due to stress or earthquake preparation, and separating the extraneous ones is a problem as daunting as understanding earthquake behavior itself. Fourth, the associations presented between anomalies and earthquakes are generally based on selected data. Validating a proposed association requires complete data on the earthquake record and the geophysical measurements over a large area and time, followed by prospective testing which allows no adjustment of parameters, criteria, etc. The Collaboratory for Study of Earthquake Predictability (CSEP) is dedicated to providing such prospective testing. Any serious proposal for prediction research should deal with the problems above, and anticipate the huge investment in time required to test hypotheses.

  18. Reevaluation of 1935 M 7.0 earthquake fault, Miaoli-Taichung Area, western Taiwan: a DEM and field study

    Science.gov (United States)

    Lin, Y. N.; Chen, Y.; Ota, Y.

    2003-12-01

    A large earthquake (M 7.0) took place in Miaoli area, western Taiwan on April 21st, 1935. Right to its south is the 1999 Chi-Chi earthquake fault, indicating it is not only tectonically but seismically active. As the previous study, the study area is located in the mature zone of a tectonic collision that occurred between Philippine sea Plate and Eurasia continental Plate. The associated surface ruptures of 1935 earthquake daylighted Tungtsichiao Fault, a tear fault trending NE in the south and Chihhu Fault, a back thrust trending N-S in the north, but no ruptures occurred in between. Strike-slip component was identified by the horizontal offset observed along Tungtsichiao Fault; however, there are still disputes on the reported field evidence. Our purposes are (1) to identify the structural behaviors of these two faults, (2) to find out what the seismogenic structure is, and (3) to reconstruct the regional geology by information given by this earthquake. By DEM interpretation and field survey, we can clearly recognize a lot of the 1935 associated features. In the west of Chihhu Fault, a series of N-S higher terraces can be identified with eastward tilted surfaces and nearly 200 m relative height. Another lower terrace is also believed being created during the 1935 earthquake, showing an east-facing scarp with a height of ca. 1.5~2 m. Outcrop investigation reveals that the late-Miocene bedrock has been easterly thrusted over the Holocene conglomerates, indicating a west-dipping fault plane. The Tungtsichiao Fault cuts through a lateritic terrace at Holi, which is supposed developed in Pleistocene. The fault scarp is only discernible in the northeastern ending. Other noticeable features are the fault related antiforms that line up along the surface rupture. There is no outcrop to show the fault geometry among bedrocks. We re-interpret the northern Chihhu Fault as the back thrust generated from a main subsurface detachment, which may be the actual seismogenic fault

  19. Recent Developments in Instrumentation for Pre-Clinical Imaging Studies

    International Nuclear Information System (INIS)

    Meikle, S.R.

    2002-01-01

    Full text: Recent advances in imaging instrumentation have led to a variety of tomograph designs for dedicated pre clinical imaging of laboratory animals. These advances make it possible to image and quantify the kinetics of radiolabelled pharmaceuticals in a wide range of animal models from rodents to non-human primates. Applications include evaluation of promising new radiopharmaceuticals, study of the molecular origins of human disease and evaluation of new forms of therapy. These applications and advances in instrumentation are equally applicable to positron emitters and single photon emitters. This paper provides an overview of recent advances which have led to the current state-of-the-art in pre clinical imaging. The common inorganic scintillators that have been used for SPECT and PET, including some of the promising materials recently studied. The current crystal of choice for SPECT imaging is NaI(Tl) because of its high light output and density which make it well suited to imaging photons in the 100-200 keV range. However, NaI(Tl) has the disadvantage that it must be hermetically sealed to prevent absorption of moisture from the environment. Therefore, investigators have explored a number of alternative inorganic crystals, including CsI(Tl) and cerium-doped yttrium aluminium perovskite (YAP), as well as solid state detectors such as cadmium zinc telluride (CZT). Many of the crystals used in SPECT have also been tried for PET, including NaI(Tl) and YAP. However these crystals have lower stopping power than BGO and NaI(Tl) is also relatively slow. A very promising scintillator for PET is cerium-doped lutetium oxyorthosilicate (LSO) (1) which has similar stopping power to BGO and relatively high light output and fast decay. The first PET scanner to use LSO was the UCLA animal scanner, microPET, which also makes use of a number of other new technologies and unique design features. Recently, improvements in multi-anode and crossed wire position sensitive

  20. Efficacy of insurance for organisational disaster recovery: case study of the 2010 and 2011 Canterbury earthquakes.

    Science.gov (United States)

    Brown, Charlotte; Seville, Erica; Vargo, John

    2017-04-01

    Insurance is widely acknowledged to be an important component of an organisation's disaster preparedness and resilience. Yet, little analysis exists of how well current commercial insurance policies and practices support organisational recovery in the wake of a major disaster. This exploratory qualitative research, supported by some quantitative survey data, evaluated the efficacy of commercial insurance following the sequence of earthquakes in Canterbury, New Zealand, in 2010 and 2011. The study found that, generally, the commercial insurance sector performed adequately, given the complexity of the events. However, there are a number of ways in which insurers could improve their operations to increase the efficacy of commercial insurance cover and to assist organisational recovery following a disaster. The most notable of these are: (i) better wording of policies; (ii) the availability of sector-specific policies; (iii) the enhancement of claims assessment systems; and (iv) risk-based policy pricing to incentivise risk reduction measures. © 2017 The Author(s). Disasters © Overseas Development Institute, 2017.

  1. Vulnerability of Eastern Caribbean Islands Economies to Large Earthquakes: The Trinidad and Tobago Case Study

    Science.gov (United States)

    Lynch, L.

    2015-12-01

    The economies of most of the Anglo-phone Eastern Caribbean islands have tripled to quadrupled in size since independence from England. There has also been commensurate growth in human and physical development as indicated by macro-economic indices such as Human Development Index and Fixed Capital Formation. A significant proportion of the accumulated wealth is invested in buildings and infrastructure which are highly susceptible to strong ground motion since the region is located along an active plate boundary. In the case of Trinidad and Tobago, Fixed Capital Formation accumulation since 1980 is almost US200 billion dollars. Recent studies have indicated that this twin island state is at significant risk from several seismic sources, both on land and offshore. To effectively mitigate the risk it is necessary to prescribe long-term measures such as the development and implementation of building code and standards, structural retrofitting, land use planning, preparedness planning and risk transfer mechanisms. The record has shown that Trinidad and Tobago has been been slow in the prescribing such measures which has consequently compounded it vulnerability to large earthquakes. This assessment reveals that the losses from a large (magnitude 7+) on land or an extreme (magnitude 8+) event could result in losses of up to US28B and that current risk transfer measures will only cater for less than ten percent of such losses.

  2. Connecting slow earthquakes to huge earthquakes

    OpenAIRE

    Obara, Kazushige; Kato, Aitaro

    2016-01-01

    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 th...

  3. Biosensors for EVA: Improved Instrumentation for Ground-based Studies

    Science.gov (United States)

    Soller, B.; Ellerby, G.; Zou, F.; Scott, P.; Jin, C.; Lee, S. M. C.; Coates, J.

    2010-01-01

    During lunar excursions in the EVA suit, real-time measurement of metabolic rate is required to manage consumables and guide activities to ensure safe return to the base. Metabolic rate, or oxygen consumption (VO2), is normally measured from pulmonary parameters but cannot be determined with standard techniques in the oxygen-rich environment of a spacesuit. Our group has developed novel near infrared spectroscopic (NIRS) methods to calculate muscle oxygen saturation (SmO 2), hematocrit, and pH, and we recently demonstrated that we can use our NIRS sensor to measure VO 2 on the leg during cycling. Our NSBRI project has 4 objectives: (1) increase the accuracy of the metabolic rate calculation through improved prediction of stroke volume; (2) investigate the relative contributions of calf and thigh oxygen consumption to metabolic rate calculation for walking and running; (3) demonstrate that the NIRS-based noninvasive metabolic rate methodology is sensitive enough to detect decrement in VO 2 in a space analog; and (4) improve instrumentation to allow testing within a spacesuit. Over the past year we have made progress on all four objectives, but the most significant progress was made in improving the instrumentation. The NIRS system currently in use at JSC is based on fiber optics technology. Optical fiber bundles are used to deliver light from a light source in the monitor to the patient, and light reflected back from the patient s muscle to the monitor for spectroscopic analysis. The fiber optic cables are large and fragile, and there is no way to get them in and out of the test spacesuit used for ground-based studies. With complimentary funding from the US Army, we undertook a complete redesign of the sensor and control electronics to build a novel system small enough to be used within the spacesuit and portable enough to be used by a combat medic. In the new system the filament lamp used in the fiber optic system was replaced with a novel broadband near infrared

  4. Passive seismic monitoring of natural and induced earthquakes: case studies, future directions and socio-economic relevance

    Science.gov (United States)

    Bohnhoff, Marco; Dresen, Georg; Ellsworth, William L.; Ito, Hisao; Cloetingh, Sierd; Negendank, Jörg

    2010-01-01

    An important discovery in crustal mechanics has been that the Earth’s crust is commonly stressed close to failure, even in tectonically quiet areas. As a result, small natural or man-made perturbations to the local stress field may trigger earthquakes. To understand these processes, Passive Seismic Monitoring (PSM) with seismometer arrays is a widely used technique that has been successfully applied to study seismicity at different magnitude levels ranging from acoustic emissions generated in the laboratory under controlled conditions, to seismicity induced by hydraulic stimulations in geological reservoirs, and up to great earthquakes occurring along plate boundaries. In all these environments the appropriate deployment of seismic sensors, i.e., directly on the rock sample, at the earth’s surface or in boreholes close to the seismic sources allows for the detection and location of brittle failure processes at sufficiently low magnitude-detection threshold and with adequate spatial resolution for further analysis. One principal aim is to develop an improved understanding of the physical processes occurring at the seismic source and their relationship to the host geologic environment. In this paper we review selected case studies and future directions of PSM efforts across a wide range of scales and environments. These include induced failure within small rock samples, hydrocarbon reservoirs, and natural seismicity at convergent and transform plate boundaries. Each example represents a milestone with regard to bridging the gap between laboratory-scale experiments under controlled boundary conditions and large-scale field studies. The common motivation for all studies is to refine the understanding of how earthquakes nucleate, how they proceed and how they interact in space and time. This is of special relevance at the larger end of the magnitude scale, i.e., for large devastating earthquakes due to their severe socio-economic impact.

  5. Mitigating mass movement caused by earthquakes and typhoons: a case study of central Taiwan

    Science.gov (United States)

    Lin, Jiun-Chuan

    2013-04-01

    Typhoons caused huge damages to Taiwan at the average of 3.8 times a year in the last 100 years, according to Central Weather Bureau data. After the Chi-Chi earthquake of 1999 at the magnitude of Richard Scale 7.3, typhoons with huge rainfall would cause huge debris flow and deposits at river channels. As a result of earthquakes, loose debris falls and flows became significant hazards in central Taiwan. Analysis of rainfall data and data about the sites of slope failure show that damage from natural hazards was enhanced in the last 20 years, as a result of the Chi-Chi earthquake. There are three main types of mass movement in Central Taiwan: landslides, debris flows and gully erosion. Landslides occurred mainly along hill slopes and river channel banks. Many dams, check dams, housing structures and even river channels can be raised to as high as 60 meters as a result of stacking up floating materials of landslides. Debris flows occurred mainly through typhoon periods and activated ancient debris deposition. New gullies were thus developed from deposits loosened and shaken up by earthquakes. Extreme earthquakes and typhoon events occurred frequently in the last 20 years. This paper analyzes the geological and geomorphologic background for the precarious areas and typhoons in central Taiwan, to make a systematic understanding of mass movement harzards. The mechanism and relations of debris flows and rainfall data in central Taiwan are analyzed. Ways for mitigating mass movement threats are also proposed in this paper. Keywords: mass movement, earthquakes, typhoons, hazard mitigation, central Ta

  6. Life-event stress induced by the Great East Japan Earthquake was associated with relapse in ulcerative colitis but not Crohn's disease: a retrospective cohort study

    Science.gov (United States)

    Shiga, Hisashi; Miyazawa, Teruko; Kinouchi, Yoshitaka; Takahashi, Seiichi; Tominaga, Gen; Takahashi, Hiroki; Takagi, Sho; Obana, Nobuya; Kikuchi, Tatsuya; Oomori, Shinya; Nomura, Eiki; Shiraki, Manabu; Sato, Yuichirou; Takahashi, Shuichiro; Umemura, Ken; Yokoyama, Hiroshi; Endo, Katsuya; Kakuta, Yoichi; Aizawa, Hiroki; Matsuura, Masaki; Kimura, Tomoya; Kuroha, Masatake; Shimosegawa, Tooru

    2013-01-01

    Objective Stress is thought to be one of the triggers of relapses in patients with inflammatory bowel disease (IBD). We examined the rate of relapse in IBD patients before and after the Great East Japan Earthquake. Design A retrospective cohort study. Settings 13 hospitals in Japan. Participants 546 ulcerative colitis (UC) and 357 Crohn's disease (CD) patients who received outpatient and inpatient care at 13 hospitals located in the area that were seriously damaged by the earthquake. Data on patient's clinical characteristics, disease activity and deleterious effects of the earthquake were obtained from questionnaires and hospital records. Primary outcome We evaluated the relapse rate (from inactive to active) across two consecutive months before and two consecutive months after the earthquake. In this study, we defined ‘active’ as conditions with a partial Mayo score=2 or more (UC) or a Harvey-Bradshaw index=6 or more (CD). Results Among the UC patients, disease was active in 167 patients and inactive in 379 patients before the earthquake. After the earthquake, the activity scores increased significantly (p<0.0001). A total of 86 patients relapsed (relapse rate=15.8%). The relapse rate was about twice that of the corresponding period in the previous year. Among the CD patients, 86 patients had active disease and 271 had inactive disease before the earthquake. After the earthquake, the activity indices changed little. A total of 25 patients experienced a relapse (relapse rate=7%). The relapse rate did not differ from that of the corresponding period in the previous year. Multivariate analyses revealed that UC, changes in dietary oral intake and anxiety about family finances were associated with the relapse. Conclusions Life-event stress induced by the Great East Japan Earthquake was associated with relapse in UC but not CD. PMID:23396562

  7. Fracture studies on stainless steel straight pipes under earthquake-type cyclic loading

    International Nuclear Information System (INIS)

    Raghava, G.; Vishnuvardhan, S.; Gandhi, P.; Vaze, K.K.

    2014-01-01

    In order to study the crack growth and cyclic fracture behaviour, which are required for realistic assessment of Leak Before Break (LBB) applicability, experimental investigations were carried out on straight pipes under quasi-crystal loading. Totally 13 pipes were tested; three were stainless steel welded (SSW) using conventional shielded metal arc welding (SMAW) technique and the remaining specimens were Narrow Gap Welded (NGW). The fracture tests were carried out under load control, displacement control and combination of the two; the pipes were subjected to different amplitudes of load or load-line displacement (LLD), which were decided based on the response of the pipes under monotonic loading. Cyclic tearing and crack growth studies on eight straight pipes of the same material reported earlier in published literature are also considered for studying the results and understanding the behaviour. Under load control, with almost equal load amplitude, the NGW pipe exhibited improved life in comparison with SMAW pipe when both are subjected to cyclic loading. The crack growth and tearing instability behaviour of the pipes were studied. The same were found to be different for load control, displacement control and combined control tests. Based in the load-controlled experimental results, material specific plot between cyclic load amplitude (as a percentage of maximum load carrying capacity of a specimen under monotonic fracture) and number of cycles to failure was obtained. The results indicate that the piping components subjected to quasi-cyclic loading may fail in very less number of cycles even when the load amplitude is sufficiently below the monotonic fracture/collapse load. These studies will be helpful in designing nuclear power plant (NPP) piping components subjected to earthquake-type cyclic loading. (author)

  8. Medical Efforts and Injury Patterns of Military Hospital Patients Following the 2013 Lushan Earthquake in China: A Retrospective Study

    Directory of Open Access Journals (Sweden)

    Peng Kang

    2015-08-01

    Full Text Available The aim of this paper is to investigate medical efforts and injury profiles of victims of the Lushan earthquake admitted to three military hospitals. This study retrospectively investigated the clinical records of 266 admitted patients evacuated from the Lushan earthquake area. The 2005 version of the Abbreviated Injury Scale (AIS-2005 was used to identify the severity of each injury. Patient demographic data, complaints, diagnoses, injury types, prognosis, means of transportation, and cause of injury were all reviewed individually. The statistical analysis of the study was conducted primarily using descriptive statistics. Of the 266 patients, 213 (80.1% were admitted in the first two days. A total of 521 injury diagnoses were recorded in 266 patients. Earthquake-related injuries were primarily caused by buildings collapsing (38.4% and victims being struck by objects (33.8%; the most frequently injured anatomic sites were the lower extremities and pelvis (34.2% and surface area of the body (17.9%. Fracture (41.5% was the most frequent injury, followed by soft tissue injury (27.5%, but crush syndrome was relatively low (1.2% due to the special housing structures in the Lushan area. The most commonly used procedure was suture and dressings (33.7%, followed by open reduction and internal fixation (21.9%.The results of this study help formulate recommendations to improve future disaster relief and emergency planning in remote, isolated, and rural regions of developing countries.

  9. Medical Efforts and Injury Patterns of Military Hospital Patients Following the 2013 Lushan Earthquake in China: A Retrospective Study.

    Science.gov (United States)

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

    2015-08-31

    The aim of this paper is to investigate medical efforts and injury profiles of victims of the Lushan earthquake admitted to three military hospitals. This study retrospectively investigated the clinical records of 266 admitted patients evacuated from the Lushan earthquake area. The 2005 version of the Abbreviated Injury Scale (AIS-2005) was used to identify the severity of each injury. Patient demographic data, complaints, diagnoses, injury types, prognosis, means of transportation, and cause of injury were all reviewed individually. The statistical analysis of the study was conducted primarily using descriptive statistics. Of the 266 patients, 213 (80.1%) were admitted in the first two days. A total of 521 injury diagnoses were recorded in 266 patients. Earthquake-related injuries were primarily caused by buildings collapsing (38.4%) and victims being struck by objects (33.8%); the most frequently injured anatomic sites were the lower extremities and pelvis (34.2%) and surface area of the body (17.9%). Fracture (41.5%) was the most frequent injury, followed by soft tissue injury (27.5%), but crush syndrome was relatively low (1.2%) due to the special housing structures in the Lushan area. The most commonly used procedure was suture and dressings (33.7%), followed by open reduction and internal fixation (21.9%).The results of this study help formulate recommendations to improve future disaster relief and emergency planning in remote, isolated, and rural regions of developing countries.

  10. Evaluation of energy efficiency policy instruments effectiveness : case study Croatia

    International Nuclear Information System (INIS)

    Bukarica, V.

    2007-01-01

    This paper proposed a theoretical basis for evaluating energy efficiency policy in the Republic of Croatia and corroborated it with the analysis of energy efficiency market development and transformation. The current status of the market was evaluated and policy instruments were adapted to achieve optimal results. In particular, the energy efficiency market in Croatia was discussed in terms of micro and macro environment factors that influence policy making processes and the choice of policy instruments. The macro environment for energy efficiency market in Croatia is the process of European Union pre-integration with all related national and international legislation, political and economical factors and potential to use financial funds. The micro environment consists of government institutions, local financing institutions and a range of market players on the supply and demand side. Energy efficiency is the most powerful and cost-effective way for achieving goals of sustainable development. Policy instruments developed to improve energy efficiency are oriented towards a cleaner environment, better standard of living, more competitive industry and improved security of energy supply. Energy efficiency is much harder to implement and requires policy interventions. In response to recent trends in the energy sector, such as deregulation and open competition, policy measures aimed at improving energy efficiency should shift from an end-users oriented approach towards a whole market approach. The optimal policy instruments mix should be designed to meet defined targets. However, market dynamics must be taken into consideration. 9 refs., 4 figs

  11. A grounded theory study of 'turning into a strong nurse': Earthquake experiences and perspectives on disaster nursing education.

    Science.gov (United States)

    Li, Yan; Turale, Sue; Stone, Teresa E; Petrini, Marcia

    2015-09-01

    While Asia has the dubious distinction of being the world's most natural disaster-prone area, disaster nursing education and training are sparse in many Asian countries, especially China where this study took place. To explore the earthquake disaster experiences of Chinese nurses and develop a substantive theory of earthquake disaster nursing that will help inform future development of disaster nursing education. A qualitative study employing grounded theory, informed by symbolic interactionism. Fifteen Chinese registered nurses from five hospitals in Jiangxi Province who undertook relief efforts after the 2008 Wenchuan Earthquake. Data were collected in 2012-2013 in digitally-recorded, semi-structured, in-depth interviews and reflective field notes, and analyzed using Glaser's grounded theory method. Participants were unprepared educationally and psychologically for their disaster work. Supporting the emergent theory of "working in that terrible environment", was the core category of "turning into a strong nurse", a process of three stages: "going to the disaster"; "immersing in the disaster"; and "trying to let disaster experiences fade away". The participants found themselves thrust in "terrible" scenes of destruction, experienced personal dangers and ethical dilemmas, and tried the best they could to help survivors, communities and themselves, with limited resources and confronting professional work. Our rich findings confirm those of other studies in China and elsewhere, that attention must be paid to disaster education and training for nurses, as well as the mental health of nurses who work in disaster areas. Emergent theory helps to inform nurse educators, researchers, leaders and policy makers in China, and elsewhere in developing strategies to better prepare nurses for future disasters, and assist communities to prepare for and recover after earthquake disasters. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. An Observational Study of Score Study Practices among Undergraduate Instrumental Music Education Majors

    Science.gov (United States)

    Silvey, Brian A.; Montemayor, Mark; Baumgartner, Christopher M.

    2017-01-01

    The purpose of this study was to investigate undergraduate instrumental music education majors' score study practices as they related to the effectiveness of their simulated conducting. Participants (N = 30) were video recorded in two sessions in which they completed a 20-min score study session and a simulated conducting performance. In the first…

  13. The study of key issues about integration of GNSS and strong-motion records for real-time earthquake monitoring

    Science.gov (United States)

    Tu, Rui; Zhang, Pengfei; Zhang, Rui; Liu, Jinhai

    2016-08-01

    This paper has studied the key issues about integration of GNSS and strong-motion records for real-time earthquake monitoring. The validations show that the consistence of the coordinate system must be considered firstly to exclude the system bias between GNSS and strong-motion. The GNSS sampling rate is suggested about 1-5 Hz, and we should give the strong-motion's baseline shift with a larger dynamic noise as its variation is very swift. The initialization time of solving the baseline shift is less than one minute, and ambiguity resolution strategy is not greatly improved the solution. The data quality is very important for the solution, we advised to use multi-frequency and multi-system observations. These ideas give an important guide for real-time earthquake monitoring and early warning by the tight integration of GNSS and strong-motion records.

  14. Dynamic strains for earthquake source characterization

    Science.gov (United States)

    Barbour, Andrew J.; Crowell, Brendan W

    2017-01-01

    Strainmeters measure elastodynamic deformation associated with earthquakes over a broad frequency band, with detection characteristics that complement traditional instrumentation, but they are commonly used to study slow transient deformation along active faults and at subduction zones, for example. Here, we analyze dynamic strains at Plate Boundary Observatory (PBO) borehole strainmeters (BSM) associated with 146 local and regional earthquakes from 2004–2014, with magnitudes from M 4.5 to 7.2. We find that peak values in seismic strain can be predicted from a general regression against distance and magnitude, with improvements in accuracy gained by accounting for biases associated with site–station effects and source–path effects, the latter exhibiting the strongest influence on the regression coefficients. To account for the influence of these biases in a general way, we include crustal‐type classifications from the CRUST1.0 global velocity model, which demonstrates that high‐frequency strain data from the PBO BSM network carry information on crustal structure and fault mechanics: earthquakes nucleating offshore on the Blanco fracture zone, for example, generate consistently lower dynamic strains than earthquakes around the Sierra Nevada microplate and in the Salton trough. Finally, we test our dynamic strain prediction equations on the 2011 M 9 Tohoku‐Oki earthquake, specifically continuous strain records derived from triangulation of 137 high‐rate Global Navigation Satellite System Earth Observation Network stations in Japan. Moment magnitudes inferred from these data and the strain model are in agreement when Global Positioning System subnetworks are unaffected by spatial aliasing.

  15. A Study of the correlation of the components of instructure motions during earthquakes

    International Nuclear Information System (INIS)

    Hudjian, A.H.

    1984-01-01

    The San Fernando earthquake of February 9, 1971 generated a large number of records in buildings throughout the Los Angeles basin. The correlation of the components of these instructure motions is studied with the expectation that an understanding of these in-situ motions could be helpful in the seismic analysis of equipment located in structures. Thirty-two buildings are selected that have all three components of motion recorded in the basement, midheight and top of the structure. The correlation coefficients of these motions, as a function of the orientation of recorder, is generated and evaluated. The effects of the structural characteristics on these motions are studied by comparing the top and midheight correlation functions with those of the basement records. Additionally, nine structures, whose design details are available in the technical literature, are selected for more detailed studies. Considering the fact that as-built structures tend to have a multitude of details that lead to non-symmetry, most of the structures studied tended towards increased correlation at the roof level. In a few cases the torsional response was accentuated due to a softening in one principal axis more than in the other as a direct result of structural damage. At midheight the correlation was reduced due to the fact that for highrise buildings the second and higher modes are significant contributors to the total structural response and tend to have a node at about this level for either of the principal axes. This midheight anomaly should not exist for the more rigid structures of nuclear power plant structures since these structures are dominated by the fundamental mode response

  16. Benefits of multidisciplinary collaboration for earthquake casualty estimation models: recent case studies

    Science.gov (United States)

    So, E.

    2010-12-01

    Earthquake casualty loss estimation, which depends primarily on building-specific casualty rates, has long suffered from a lack of cross-disciplinary collaboration in post-earthquake data gathering. An increase in our understanding of what contributes to casualties in earthquakes involve coordinated data-gathering efforts amongst disciplines; these are essential for improved global casualty estimation models. It is evident from examining past casualty loss models and reviewing field data collected from recent events, that generalized casualty rates cannot be applied globally for different building types, even within individual countries. For a particular structure type, regional and topographic building design effects, combined with variable material and workmanship quality all contribute to this multi-variant outcome. In addition, social factors affect building-specific casualty rates, including social status and education levels, and human behaviors in general, in that they modify egress and survivability rates. Without considering complex physical pathways, loss models purely based on historic casualty data, or even worse, rates derived from other countries, will be of very limited value. What’s more, as the world’s population, housing stock, and living and cultural environments change, methods of loss modeling must accommodate these variables, especially when considering casualties. To truly take advantage of observed earthquake losses, not only do damage surveys need better coordination of international and national reconnaissance teams, but these teams must integrate difference areas of expertise including engineering, public health and medicine. Research is needed to find methods to achieve consistent and practical ways of collecting and modeling casualties in earthquakes. International collaboration will also be necessary to transfer such expertise and resources to the communities in the cities which most need it. Coupling the theories and findings from

  17. Regional differences in the psychological recovery of Christchurch residents following the 2010/2011 earthquakes: a longitudinal study.

    Science.gov (United States)

    Greaves, Lara M; Milojev, Petar; Huang, Yanshu; Stronge, Samantha; Osborne, Danny; Bulbulia, Joseph; Grimshaw, Michael; Sibley, Chris G

    2015-01-01

    We examined changes in psychological distress experienced by residents of Christchurch following two catastrophic earthquakes in late 2010 and early 2011, using data from the New Zealand Attitudes and Values Study (NZAVS), a national probability panel study of New Zealand adults. Analyses focused on the 267 participants (172 women, 95 men) who were living in central Christchurch in 2009 (i.e., before the Christchurch earthquakes), and who also provided complete responses to our yearly panel questionnaire conducted in late 2010 (largely between the two major earthquakes), late 2011, and late 2012. Levels of psychological distress were similar across the different regions of central Christchurch immediately following the September 2010 earthquake, and remained comparable across regions in 2011. By late 2012, however, average levels of psychological distress in the regions had diverged as a function of the amount of property damage experienced within each given region. Specifically, participants in the least damaged region (i.e., the Fendalton-Waimairi and Riccarton-Wigram wards) experienced greater drops in psychological distress than did those in the moderately damaged region (i.e., across the Spreydon-Heathcote and Hagley-Ferrymead wards). However, the level of psychological distress reported by participants in the most damaged region (i.e., across Shirley-Papanui and Burwood-Pegasus) were not significantly different to those in the least damaged region of central Christchurch. These findings suggest that different patterns of psychological recovery emerged across the different regions of Christchurch, with the moderately damaged region faring the worst, but only after the initial shock of the destruction had passed.

  18. Study of temporal sequences of LANSAT images to detect the accumulation of stress prior of strong earthquakes in Chile.

    Science.gov (United States)

    Arellano-Baeza, A. A.

    2016-12-01

    We studied the temporal evolution of the lineaments obtained from the LANSAT-8 associated to the accumulation of stress patterns related to the seismic activity. A lineament is generally defined as a straight or a somewhat curved feature in the landscape visible in a satellite image as an aligned sequence of pixels of a contrasting intensity compared to the background. The system of lineaments extracted from the satellite images is not identical to the geological lineaments; nevertheless, it generally reflects the structure of the faults and fractures in the Earth's crust. The satellite images were processed by the ADALGEO software developed by us. We selected two areas of study with different characteristics. The first area is located near to the Diego de Almagro town in the Copiapo region, Chile. This area did not show any strong seismic activity between 2010 and 2015. However, two strong earthquakes took place later on April 16, 2016 (Mw=5.3) and July 25, 2016 (Mw=6.1). The second area located near the Illapel town in Coquimbo region shows lack of strong earthquakes between 2010 and 2012 and strong seismic activity between 2012 and 2015, culminating by the September 16, 2015 earthquake (Mw=8.3). The distance between two areas is nearly 600 km. In case of the Diego de Almagro area, very few lineaments have been observed between 2010 and 2015, showing a significant increase during the 2016. In case of the Illapel region, the number of lineaments was always much higher, showing an explosive increase at the end of 2015. For both areas the lineaments changed its orientation before strong earthquakes.

  19. An integrated approach for analysing earthquake-induced surface effects: A case study from the Northern Apennines, Italy

    Science.gov (United States)

    Castaldini, D.; Genevois, R.; Panizza, M.; Puccinelli, A.; Berti, M.; Simoni, A.

    This paper illustrates research addressing the subject of the earthquake-induced surface effects by means of a multidisciplinary approach: tectonics, neotectonics, seismology, geology, hydrogeology, geomorphology, soil/rock mechanics have been considered. The research is aimed to verify in areas affected by earthquake-triggered landslides a methodology for the identification of potentially unstable areas. The research was organized according to regional and local scale studies. In order to better emphasise the complexity of the relationships between all the parameters affecting the stability conditions of rock slopes in static and dynamic conditions a new integrated approach, Rock Engineering Systems (RES), was applied in the Northern Apennines. In the paper, the different phases of the research are described in detail and an example of the application of RES method in a sample area is reported. A significant aspect of the study can be seen in its attempt to overcome the exclusively qualitative aspects of research into the relationship between earthquakes and induced surface effects, and to advance the idea of beginning a process by which this interaction can be quantified.

  20. Earthquake number forecasts testing

    Science.gov (United States)

    Kagan, Yan Y.

    2017-10-01

    We study the distributions of earthquake numbers in two global earthquake catalogues: Global Centroid-Moment Tensor and Preliminary Determinations of Epicenters. The properties of these distributions are especially required to develop the number test for our forecasts of future seismic activity rate, tested by the Collaboratory for Study of Earthquake Predictability (CSEP). A common assumption, as used in the CSEP tests, is that the numbers are described by the Poisson distribution. It is clear, however, that the Poisson assumption for the earthquake number distribution is incorrect, especially for the catalogues with a lower magnitude threshold. In contrast to the one-parameter Poisson distribution so widely used to describe earthquake occurrences, the negative-binomial distribution (NBD) has two parameters. The second parameter can be used to characterize the clustering or overdispersion of a process. We also introduce and study a more complex three-parameter beta negative-binomial distribution. We investigate the dependence of parameters for both Poisson and NBD distributions on the catalogue magnitude threshold and on temporal subdivision of catalogue duration. First, we study whether the Poisson law can be statistically rejected for various catalogue subdivisions. We find that for most cases of interest, the Poisson distribution can be shown to be rejected statistically at a high significance level in favour of the NBD. Thereafter, we investigate whether these distributions fit the observed distributions of seismicity. For this purpose, we study upper statistical moments of earthquake numbers (skewness and kurtosis) and compare them to the theoretical values for both distributions. Empirical values for the skewness and the kurtosis increase for the smaller magnitude threshold and increase with even greater intensity for small temporal subdivision of catalogues. The Poisson distribution for large rate values approaches the Gaussian law, therefore its skewness

  1. A scanning electron microscopic study of smear layer remaining following use of Greater Taper rotary instruments

    Directory of Open Access Journals (Sweden)

    S Soumya

    2011-01-01

    Full Text Available The aim of this in vitro study was to evaluate the smear layer in the root canal following the use of Ni-Ti hand ProTaper, HERO shaper and Twisted rotary instruments. Fifteen freshly extracted single rooted human mandibular premolar teeth were selected. Crowns of all teeth were cut off at the cemento-enamel junction with a carborundum disc. The roots were then randomly divided into three groups of 5 samples each. The working length of all teeth was established by the insertion of an endodontic instrument into the canal until its tip is visible at the apical foramen and then subtracted by 0.5 mm. A sequential crown down technique was carried out in all the three groups as follows: Group-I- Specimens in this group were instrumented with ProTaper Ni-Ti hand instruments. Group-II- Specimens were instrumented with HERO shapers. Group-III - The specimens in this group were instrumented with Twisted rotary instruments. Irrigation was done with 3% NaOCl and 15% EDTA in all the three groups. Teeth were carefully split with hammer and chisel and stored in small labeled bottles containing normal saline until SEM evaluation. Results showed that when comparing ProTaper files, Twisted rotary instruments and HERO shaper instruments, HERO shaper series of rotary instruments showed maximum amount of smear layer followed by the Twisted rotary instruments. Hand instruments produced least amount of smear layer.

  2. Data- and Tool-rich Curriculum on Natural Catastrophes: Case Study of M9+ Earthquakes and Mega-tsunamis in Cascadia

    Science.gov (United States)

    Mayhew, M.; Hall, M.; Walker, C. S.; Butler, R. F.

    2008-12-01

    We report on one of four undergraduate curriculum units on natural catastrophes that make use of a wide range of geologic and geophysical data sets and data visualization and analysis tools. All units use My World GIS tools, Google Earth, Excel, animations, and video. In the Cascadia case study, students conduct a series of investigations concerning evidence of M9+ earthquakes in the past and evidence of present-day deformation consistent with the likelihood of another such earthquake some time in the future. The unit begins with Native oral traditions that predate European settlement of the region in the mid-18th century that tell of a huge earthquake and accompanying tsunami. The scene shifts to the great M9+ Sumatra earthquake of 2004 as a possible analog. Students analyze GPS and other data related to horizontal and vertical motions accompanying the earthquake. Comparisons of deformation patterns and rupture zone extent among the 2004 M9+ Sumatran, 1960 M9+ Chilean and the 1964 M9+ Alaskan earthquakes are made with a possible Cascadian analog. Students analyze Cascadia GPS data from the Plate Boundary Observatory and investigate strain accumulation patterns consistent with a locked zone at the shallow part of the subduction zone. They then use geologic evidence to evaluate the possibility of great earthquakes in the past. They do this much in the same way that geologists have, noting the distinctive stratigraphic evidence of catastrophic subsidence and tsunami inundation, directly analogous to the effects accompanying the other great earthquakes they have studied. They determine the year, date, and time of the last great earthquake that occurred here, by linking to the Japanese historical record of an "Orphan Tsunami" that devastated Japan in 1700. They note evidence from coastal estuarian stratigraphy and from deep sea cores in the Cascadia Basin of multiple great earthquakes over the last 10,000 years and compute recurrence intervals. They then conduct a

  3. Sediment gravity flows triggered by remotely generated earthquake waves

    Science.gov (United States)

    Johnson, H. Paul; Gomberg, Joan S.; Hautala, Susan L.; Salmi, Marie S.

    2017-06-01

    Recent great earthquakes and tsunamis around the world have heightened awareness of the inevitability of similar events occurring within the Cascadia Subduction Zone of the Pacific Northwest. We analyzed seafloor temperature, pressure, and seismic signals, and video stills of sediment-enveloped instruments recorded during the 2011-2015 Cascadia Initiative experiment, and seafloor morphology. Our results led us to suggest that thick accretionary prism sediments amplified and extended seismic wave durations from the 11 April 2012 Mw8.6 Indian Ocean earthquake, located more than 13,500 km away. These waves triggered a sequence of small slope failures on the Cascadia margin that led to sediment gravity flows culminating in turbidity currents. Previous studies have related the triggering of sediment-laden gravity flows and turbidite deposition to local earthquakes, but this is the first study in which the originating seismic event is extremely distant (> 10,000 km). The possibility of remotely triggered slope failures that generate sediment-laden gravity flows should be considered in inferences of recurrence intervals of past great Cascadia earthquakes from turbidite sequences. Future similar studies may provide new understanding of submarine slope failures and turbidity currents and the hazards they pose to seafloor infrastructure and tsunami generation in regions both with and without local earthquakes.

  4. Radon/helium studies for earthquake prediction N-W Himalaya

    International Nuclear Information System (INIS)

    Virk, H.S.

    1999-01-01

    The paper presents the preliminary data of radon monitoring stated in the Himalayan orogenic belt. Radon anomalies are correlated with microseismic activity in the N-W Himalaya. The He/Rn ratio will be used as a predictive tool for earthquakes

  5. Seeking Information after the 2010 Haiti Earthquake: A Case Study in Mass-Fatality Management

    Science.gov (United States)

    Gupta, Kailash

    2013-01-01

    The 2010 earthquake in Haiti, which killed an estimated 316,000 people, offered many lessons in mass-fatality management (MFM). The dissertation defined MFM in seeking information and in recovery, preservation, identification, and disposition of human remains. Specifically, it examined how mass fatalities were managed in Haiti, how affected…

  6. Study of parental models: building an instrument for their exploration

    Directory of Open Access Journals (Sweden)

    José Francisco Martínez Licona

    2014-08-01

    Full Text Available Objective: This research presents the construction of an attributional questionnaire concerning the different parental models and factors that are involved in family interactions. Method: A mixed methodology was used as a foundation to develop items and respective pilots that allowed checking the validity and internal consistency of the instrument using expert judgment. Results: An instrument of 36 statements was organized into 12 categories to explore the parental models according to the following factors: parental models, breeding patterns, attachment bonds and guidelines for success, and promoted inside family contexts. Analyzing these factors contributes to the children’s development within the familiar frown, and the opportunity for socio-educational intervention. Conclusion: It is assumed that the family context is as decisive as the school context; therefore, exploring the nature of parental models is required to understand the features and influences that contribute to the development of young people in any social context.

  7. Resource loss, self-efficacy, and family support predict posttraumatic stress symptoms: a 3-year study of earthquake survivors.

    Science.gov (United States)

    Warner, Lisa Marie; Gutiérrez-Doña, Benicio; Villegas Angulo, Maricela; Schwarzer, Ralf

    2015-01-01

    Social support and self-efficacy are regarded as coping resources that may facilitate readjustment after traumatic events. The 2009 Cinchona earthquake in Costa Rica serves as an example for such an event to study resources to prevent subsequent severity of posttraumatic stress symptoms. At Time 1 (1-6 months after the earthquake in 2009), N=200 survivors were interviewed, assessing resource loss, received family support, and posttraumatic stress response. At Time 2 in 2012, severity of posttraumatic stress symptoms and general self-efficacy beliefs were assessed. Regression analyses estimated the severity of posttraumatic stress symptoms accounted for by all variables. Moderator and mediator models were examined to understand the interplay of received family support and self-efficacy with posttraumatic stress symptoms. Baseline posttraumatic stress symptoms and resource loss (T1) accounted for significant but small amounts of the variance in the severity of posttraumatic stress symptoms (T2). The main effects of self-efficacy (T2) and social support (T1) were negligible, but social support buffered resource loss, indicating that only less supported survivors were affected by resource loss. Self-efficacy at T2 moderated the support-stress relationship, indicating that low levels of self-efficacy could be compensated by higher levels of family support. Receiving family support at T1 enabled survivors to feel self-efficacious, underlining the enabling hypothesis. Receiving social support from relatives shortly after an earthquake was found to be an important coping resource, as it alleviated the association between resource loss and the severity of posttraumatic stress response, compensated for deficits of self-efficacy, and enabled self-efficacy, which was in turn associated with more adaptive adjustment 3 years after the earthquake.

  8. A study on cigarette tobacco by instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Md Soot Haji Ahmad; Tey Nsan Yen

    1987-01-01

    The concentration of 25 elements in cigarette tobacco of popular brands locally marketed were determined using instrumental neutron activation analysis. These elements are: Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Mg, Mn, Na, Rb, Sb, Sc, Se, Sr, Th, and Zn. Comparison of the element contents to the reported cigarette tobacco of Egypt, Iran and Turkey was also done. (author)

  9. Development of a new haptic perception instrument: a pilot study

    OpenAIRE

    Nascimento, Leonardo Penteado; Martini, Joyce; Voos, Mariana Callil; Chien, Hsin Fen; Caromano, Fátima Aparecida

    2015-01-01

    ABSTRACT Objective Hand sensory tests do not consider distinct physiological receptors, nor detect normal range variations concerning developmental or pathological changes. We developed an instrument with a set of tests with timing and scoring for assessing haptic perception, which is the interaction between sensory and motor systems, in surfaces exploration, by moving hands. Method Firstly, group meetings were set for test/manual conception and materials testing. The test/manual were sub...

  10. The fine structure of the dynamics of seismicity before earthquakes in the area of Reggio Emilia (Northern Italy

    Directory of Open Access Journals (Sweden)

    Y. Tyupki

    1999-06-01

    Full Text Available We present the results of studies of seismicity in the Reggio Emilia area (Northern Italy. The Istituto Nazionale di Geofisica instrumental earthquake catalogue (1975-1996 reported about three moderate-size earthquakes with M ³ 4.5 that occurred in this area (November 1983, May 1987, October 1996. The RTL prognostic parameter proposed by Sobolev and Tyupkin (1996a was used for analysis. This parameter is designed in such a way that a seismic quiescence produces negative anomaly of the RTL parameter in comparison to its perennial background level and an activation of seismicity initiates the growth of its value. The RTL prognostic parameter indicates that all three earthquakes are preceded by activation of the seismicity. The interval between the commencement of the activation identified by RTL parameter and the event itself was about one year for the 1987 and 1996 earthquakes, and about three months for the 1983 earthquake.

  11. Analyses of computer programs for the probabilistic estimation of design earthquake and seismological characteristics of the Korean Peninsula

    International Nuclear Information System (INIS)

    Lee, Gi Hwa

    1997-11-01

    The purpose of the present study is to develop predictive equations from simulated motions which are adequate for the Korean Peninsula and analyze and utilize the computer programs for the probabilistic estimation of design earthquakes. In part I of the report, computer programs for the probabilistic estimation of design earthquake are analyzed and applied to the seismic hazard characterizations in the Korean Peninsula. In part II of the report, available instrumental earthquake records are analyzed to estimate earthquake source characteristics and medium properties, which are incorporated into simulation process. And earthquake records are simulated by using the estimated parameters. Finally, predictive equations constructed from the simulation are given in terms of magnitude and hypocentral distances

  12. Acute stress disorder as a predictor of posttraumatic stress: A longitudinal study of Chinese children exposed to the Lushan earthquake.

    Science.gov (United States)

    Zhou, Peiling; Zhang, Yuqing; Wei, Chuguang; Liu, Zhengkui; Hannak, Walter

    2016-09-01

    This study examined the prevalence of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) in children who experienced the Lushan earthquake in Sichuan, China, and assessed the ability of ASD to predict PTSD. The Acute Stress Disorder Scale (ASDS) was used to assess acute stress reaction within weeks of the trauma. The University of California at Los Angeles Post-Traumatic Stress Disorder Reaction Index (UCLA-PTSD) for children was administered at intervals of 2, 6, and 12 months after the earthquake to 197 students who experienced the Lushan earthquake at the Longxing Middle School. The results demonstrated that 28.4% of the children suffered from ASD, but only a small percentage of the population went on to develop PTSD. Among all of the students, 35.0% of those who met the criteria for ASD were diagnosed with PTSD at the 12-month interval. The severity of ASD symptoms correlated with later PTSD symptoms. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  13. Prospective study of predictors of poor self-rated health in a 23-year cohort of earthquake survivors in Armenia

    Directory of Open Access Journals (Sweden)

    Anahit Demirchyan

    2015-09-01

    Full Text Available Long-term prospective studies exploring general health outcomes among disaster survivors are rare. Self-rated health (SRH – a proven correlate of morbidity and mortality prognosis – was used to investigate predictors of perceived health status among a 23-year cohort of survivors of 1988 Spitak earthquake in Armenia. A geographically-stratified subsample of 725 adults from a larger initial cohort was followed during the period of 1990–2012. A logistic regression model identified predictors of SRH. Adjusted relative risks for the long-term predictors of SRH were calculated. The rate of poor SRH among the survivors was 18.8%, fair 56.5%, and good/excellent 24.7%. In the fitted model, long-term risk factors of poor SRH included baseline body mass index, baseline multi-morbidity, number of experienced stressful life events, and perceived poor living standards during the post-earthquake decade, while participation in sports in the early 1990s was a protective factor. Short-term protective factors included socio-economic status score, social support, employment and dignity, while current household size was a risk factor for poor SRH. No association was found between earthquake exposure severity and SRH after 23 years. However, the identified predictors included a number of modifiable lifestyle, material and psychological factors. Thus, interventions targeting these factors could have a long-lasting impact on disaster victims’ health status.

  14. The 2016 Central Italy Earthquake: an Overview

    Science.gov (United States)

    Amato, A.

    2016-12-01

    The M6 central Italy earthquake occurred on the seismic backbone of the Italy, just in the middle of the highest hazard belt. The shock hit suddenly during the night of August 24, when people were asleep; no foreshocks occurred before the main event. The earthquake ruptured from 10 km to the surface, and produced a more than 17,000 aftershocks (Oct. 19) spread on a 40x20 km2 area elongated NW-SE. It is geologically very similar to previous recent events of the Apennines. Both the 2009 L'Aquila earthquake to the south and the 1997 Colfiorito to the north, were characterized by the activation of adjacent fault segments. Despite its magnitude and the well known seismic hazard of the region, the earthquake produced extensive damage and 297 fatalities. The town of Amatrice, that paid the highest toll, was classified in zone 1 (the highest) since 1915, but the buildings in this and other villages revealed highly vulnerable. In contrast, in the town of Norcia, that also experienced strong ground shaking, no collapses occurred, most likely due to the retrofitting carried out after an earthquake in 1979. Soon after the quake, the INGV Crisis Unit convened at night in the Rome headquarters, in order to coordinate the activities. The first field teams reached the epicentral area at 7 am with the portable seismic stations installed to monitor the aftershocks; other teams followed to map surface faults, damage, to measure GPS sites, to install instruments for site response studies, and so on. The INGV Crisis Unit includes the Press office and the INGVterremoti team, in order to manage and coordinate the communication towards the Civil Protection Dept. (DPC), the media and the web. Several tens of reports and updates have been delivered in the first month of the sequence to DPC. Also due to the controversial situation arisen from the L'Aquila earthquake and trials, particular attention was given to the communication: continuous and timely information has been released to

  15. Deterministic Earthquake Hazard Assessment by Public Agencies in California

    Science.gov (United States)

    Mualchin, L.

    2005-12-01

    Even in its short recorded history, California has experienced a number of damaging earthquakes that have resulted in new codes and other legislation for public safety. In particular, the 1971 San Fernando earthquake produced some of the most lasting results such as the Hospital Safety Act, the Strong Motion Instrumentation Program, the Alquist-Priolo Special Studies Zone Act, and the California Department of Transportation (Caltrans') fault-based deterministic seismic hazard (DSH) map. The latter product provides values for earthquake ground motions based on Maximum Credible Earthquakes (MCEs), defined as the largest earthquakes that can reasonably be expected on faults in the current tectonic regime. For surface fault rupture displacement hazards, detailed study of the same faults apply. Originally, hospital, dam, and other critical facilities used seismic design criteria based on deterministic seismic hazard analyses (DSHA). However, probabilistic methods grew and took hold by introducing earthquake design criteria based on time factors and quantifying "uncertainties", by procedures such as logic trees. These probabilistic seismic hazard analyses (PSHA) ignored the DSH approach. Some agencies were influenced to adopt only the PSHA method. However, deficiencies in the PSHA method are becoming recognized, and the use of the method is now becoming a focus of strong debate. Caltrans is in the process of producing the fourth edition of its DSH map. The reason for preferring the DSH method is that Caltrans believes it is more realistic than the probabilistic method for assessing earthquake hazards that may affect critical facilities, and is the best available method for insuring public safety. Its time-invariant values help to produce robust design criteria that are soundly based on physical evidence. And it is the method for which there is the least opportunity for unwelcome surprises.

  16. Southern California Earthquake Center/Undergraduate Studies in Earthquake Information Technology (SCEC/UseIT): Towards the Next Generation of Internship

    Science.gov (United States)

    Perry, S.; Benthien, M.; Jordan, T. H.

    2005-12-01

    The SCEC/UseIT internship program is training the next generation of earthquake scientist, with methods that can be adapted to other disciplines. UseIT interns work collaboratively, in multi-disciplinary teams, conducting computer science research that is needed by earthquake scientists. Since 2002, the UseIT program has welcomed 64 students, in some two dozen majors, at all class levels, from schools around the nation. Each summer''s work is posed as a ``Grand Challenge.'' The students then organize themselves into project teams, decide how to proceed, and pool their diverse talents and backgrounds. They have traditional mentors, who provide advice and encouragement, but they also mentor one another, and this has proved to be a powerful relationship. Most begin with fear that their Grand Challenge is impossible, and end with excitement and pride about what they have accomplished. The 22 UseIT interns in summer, 2005, were primarily computer science and engineering majors, with others in geology, mathematics, English, digital media design, physics, history, and cinema. The 2005 Grand Challenge was to "build an earthquake monitoring system" to aid scientists who must visualize rapidly evolving earthquake sequences and convey information to emergency personnel and the public. Most UseIT interns were engaged in software engineering, bringing new datasets and functionality to SCEC-VDO (Virtual Display of Objects), a 3D visualization software that was prototyped by interns last year, using Java3D and an extensible, plug-in architecture based on the Eclipse Integrated Development Environment. Other UseIT interns used SCEC-VDO to make animated movies, and experimented with imagery in order to communicate concepts and events in earthquake science. One movie-making project included the creation of an assessment to test the effectiveness of the movie''s educational message. Finally, one intern created an interactive, multimedia presentation of the UseIT program.

  17. Unusual downhole and surface free-field records near the Carquinez Strait bridges during the 24 August 2014 Mw6.0 South Napa, California earthquake

    Science.gov (United States)

    Çelebi, Mehmet; Ghahari, S. Farid; Taciroglu, Ertugrul

    2015-01-01

    This paper reports the results of Part A of a study of the recorded strong-motion accelerations at the well-instrumented network of the two side-by-side parallel bridges over the Carquinez Strait during the 24 August 2014 (Mw6.0 ) South Napa, Calif. earthquake that occurred at 03:20:44 PDT with epicentral coordinates 38.22N, 122.31W. (http://earthquake.usgs.gov/earthquakes/eqarchives/poster/2014/20140824.php, last accessed on October 17, 2014). Both bridges and two boreholes were instrumented by the California Strong motion Instrumentation Program (CSMIP) of California Geological Survey (CGS) (Shakal et al., 2014). A comprehensive comparison of several ground motion prediction equations as they relate to recorded ground motions of the earthquake is provided by Baltay and Boatright (2015).

  18. PRECURSORS OF EARTHQUAKES: VLF SIGNALSIONOSPHERE IONOSPHERE RELATION

    Directory of Open Access Journals (Sweden)

    Mustafa ULAS

    2013-01-01

    Full Text Available lot of people have died because of earthquakes every year. Therefore It is crucial to predict the time of the earthquakes reasonable time before it had happed. This paper presents recent information published in the literature about precursors of earthquakes. The relationships between earthquakes and ionosphere are targeted to guide new researches in order to study further to find novel prediction methods.

  19. Understanding Earthquakes

    Science.gov (United States)

    Davis, Amanda; Gray, Ron

    2018-01-01

    December 26, 2004 was one of the deadliest days in modern history, when a 9.3 magnitude earthquake--the third largest ever recorded--struck off the coast of Sumatra in Indonesia (National Centers for Environmental Information 2014). The massive quake lasted at least 10 minutes and devastated the Indian Ocean. The quake displaced an estimated…

  20. Rupture, waves and earthquakes.

    Science.gov (United States)

    Uenishi, Koji

    2017-01-01

    Normally, an earthquake is considered as a phenomenon of wave energy radiation by rupture (fracture) of solid Earth. However, the physics of dynamic process around seismic sources, which may play a crucial role in the occurrence of earthquakes and generation of strong waves, has not been fully understood yet. Instead, much of former investigation in seismology evaluated earthquake characteristics in terms of kinematics that does not directly treat such dynamic aspects and usually excludes the influence of high-frequency wave components over 1 Hz. There are countless valuable research outcomes obtained through this kinematics-based approach, but "extraordinary" phenomena that are difficult to be explained by this conventional description have been found, for instance, on the occasion of the 1995 Hyogo-ken Nanbu, Japan, earthquake, and more detailed study on rupture and wave dynamics, namely, possible mechanical characteristics of (1) rupture development around seismic sources, (2) earthquake-induced structural failures and (3) wave interaction that connects rupture (1) and failures (2), would be indispensable.

  1. Twitter earthquake detection: Earthquake monitoring in a social world

    Science.gov (United States)

    Earle, Paul S.; Bowden, Daniel C.; Guy, Michelle R.

    2011-01-01

    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 USGS earthquake response products and the delivery of hazard information. Rapid detection and qualitative assessment of shaking events are possible because people begin sending public Twitter messages (tweets) with in tens of seconds after feeling shaking. Here we present and evaluate an earthquake detection procedure that relies solely on Twitter data. A tweet-frequency time series constructed from tweets containing the word "earthquake" clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a short-term-average, long-term-average algorithm. When tuned to a moderate sensitivity, the detector finds 48 globally-distributed earthquakes with only two false triggers in five months of data. The number of detections is small compared to the 5,175 earthquakes in the USGS global earthquake catalog for the same five-month time period, and no accurate location or magnitude can be assigned based on tweet data alone. However, Twitter earthquake detections are not without merit. The detections are generally caused by widely felt events that are of more immediate interest than those with no human impact. The detections are also fast; about 75% occur within two minutes of the origin time. This is considerably faster than seismographic detections in poorly instrumented regions of the world. The tweets triggering the detections also provided very short first-impression narratives from people who experienced the shaking.

  2. Modeling, Forecasting and Mitigating Extreme Earthquakes

    Science.gov (United States)

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

    2012-12-01

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

  3. Mental health problems among children and adolescents experiencing two major earthquakes in remote mountainous regions: A longitudinal study.

    Science.gov (United States)

    Tang, Wanjie; Zhao, Jingdong; Lu, Yi; Yan, Tingting; Wang, Lijuan; Zhang, Jun; Xu, Jiuping

    2017-01-01

    Millions of children were exposed to major earthquake in China, with serious psychological and developmental consequences. To obtain accurate rate of post-disaster related disorder and identify predictors may help inform post-disaster rescue and rehabilitation efforts. The present longitudinal study explored correlations of demographic and socioeconomic characteristics of juvenile survivors of the Ya'an and Wenchuan earthquakes in China with their trajectories of post-disaster related disorder. A total of 435 Chinese children and adolescents who survived the 2013 Ya'an earthquake were recruited from six primary, secondary and high schools in Baoxing County. All survivors were assessed at 12months after the disaster, when a trained psychiatrist assessed mental health problems in a face-to-face structured interview, and 153 survivors were followed up at 30months after the earthquake via telephone. The 12-month assessment indicated a post-traumatic stress disorder (PTSD) prevalence of 43.9% as well as depression (20.9%) or the criteria for both PTSD and depression (18.2%) and the other disorder (0.9%). The 30-month assessment indicated that 15.7% of subjects met the criteria for PTSD, 21.6% met the criteria for depression. No subjects met the criteria for other affective or anxiety disorders. Significant predictors of PTSD and depression were death in the family, previous earthquake experience, a poor parent-child relationship and economic pressure or poverty. Clinical interview face to face is quite different from via telephone and the attrition rate in the longitudinal cohort is high, which would directly affect our results of the assessment. PTSD and depression may be as prevalent and persistent in disaster victims in China as elsewhere, and high co-comorbidities remain poorly understood. Although many adolescents recover over time, some exhibit chronic, delayed-onset PTSD and depression, especially those with poor relationships with their parents or those living

  4. Analysis and modeling of safety parameters in the selection of optimal routes for emergency evacuation after the earthquake (Case study: 13 Aban neighborhood of Tehran

    Directory of Open Access Journals (Sweden)

    Sajad Ganjehi

    2013-08-01

    Full Text Available Introduction : Earthquakes are imminent threats to urban areas of Iran, especially Tehran. They can cause extensive destructions and lead to heavy casualties. One of the most important aspects of disaster management after earthquake is the rapid transfer of casualties to emergency shelters. To expedite emergency evacuation process the optimal safe path method should be considered. To examine the safety of road networks and to determine the most optimal route at pre-earthquake phase, a series of parameters should be taken into account.   Methods : In this study, we employed a multi-criteria decision-making approach to determine and evaluate the effective safety parameters for selection of optimal routes in emergency evacuation after an earthquake.   Results: The relationship between the parameters was analyzed and the effect of each parameter was listed. A process model was described and a case study was implemented in the 13th Aban neighborhood ( Tehran’s 20th municipal district . Then, an optimal path to safe places in an emergency evacuation after an earthquake in the 13th Aban neighborhood was selected.   Conclusion : Analytic hierarchy process (AHP, as the main model, was employed. Each parameter of the model was described. Also, the capabilities of GIS software such as layer coverage were used.     Keywords: Earthquake, emergency evacuation, Analytic Hierarchy Process (AHP, crisis management, optimization, 13th Aban neighborhood of Tehran

  5. Multiple parameters anomalies for verifying the geosystem spheres coupling effect: a case study of the 2010 Ms7.1 Yushu earthquake in China

    Directory of Open Access Journals (Sweden)

    Shuo Zheng

    2014-08-01

    Full Text Available In the research of earthquake anomaly recognition, the coupling effect of multiple geosystem spheres can be expected to reasonably interpretating the correlation between various anomalous signals before strong earthquake. Specially, the development of the Lithosphere–Atmosphere–Ionosphere (LAI coupling model has been accepted as verified by some experimental, thermal and electromagnetic data. However, quasi-synchronous anomalies of the multiple parameters, including thermal, radon and electromagnetic data, have not been reported in a single event case for verifying the geosystem spheres coupling effect. In this paper, we firstly summarized the reported studies on the power spectrum density (PSD in the ELF/VLF band and radon data recorded from Guza seismic station. Then, historical surface latent heat flux (SLHF data from the NCEP/NCAR Reanalysis Project was employed for investigating anomalous change in a month before the April 14, 2010, Ms7.1 Yushu earthquake which is one of the typical intra-continental earthquakes in Tibet Plateau. The results from spatial and temporal analysis revealed that anomalous fields of PSD and SLHF data were located close to the epicenter and the ends of some active faults at Bayan Har Block and all anomalous dates converged between April 8 and 11 (6 to 3 days before the Yushu earthquake. Therefore, we suggest that the anomalies of multiple parameters before the main shock are related with the Yushu earthquake. This paper could give an ideal case study to verify the geosystem spheres coupling effect happened in a single event.

  6. An autosampling differential scanning calorimeter instrument for studying molecular interactions.

    Science.gov (United States)

    Plotnikov, Valerian; Rochalski, Andrew; Brandts, Michael; Brandts, John F; Williston, Samuel; Frasca, Verna; Lin, Lung-Nan

    2002-11-01

    A new ultrasensitive differential scanning calorimeter (DSC) instrument is described, which utilizes autosampling for continuous operation. High scanning rates to 250 deg/h with rapid cooling and equilibration between scans facilitates higher sample throughput up to 50 samples during each 24 h of unattended operation. The instrument is suited for those pharmaceutical applications where higher throughput is important, such as screening drug candidates for binding constant or screening solution conditions for stability of liquid protein formulations. Results are presented on the binding of five different anionic inhibitors to ribonuclease A, which included cytidine 2'-monophosphate (2'CMP), 3'CMP, uridine 3'-monophosphate, pyrophosphate, and phosphate. Binding constants K(B) (or dissociation constants K(d)) are obtained from the shift in the transition temperature T(M) for ribonuclease thermal unfolding in the presence of ligand relative to the transition temperature in the absence of ligand. Measured binding constants ranged from 155 M(-1) (K(d) = 6.45 mM) for the weak-binding phosphate anion to 13100 M(-1) (K(d) = 76.3 microM) for the strongest binding ligand, 2'CMP. The DSC method for measuring binding constants can also be extended to ultratight interactions involving either ligand-protein or protein-protein binding.

  7. Sensitivity of Coulomb stress changes to slip models of source faults: A case study for the 2011 Mw 9.0 Tohoku-oki earthquake

    Science.gov (United States)

    Wang, J.; Xu, C.; Furlong, K.; Zhong, B.; Xiao, Z.; Yi, L.; Chen, T.

    2017-12-01

    Although Coulomb stress changes induced by earthquake events have been used to quantify stress transfers and to retrospectively explain stress triggering among earthquake sequences, realistic reliable prospective earthquake forecasting remains scarce. To generate a robust Coulomb stress map for earthquake forecasting, uncertainties in Coulomb stress changes associated with the source fault, receiver fault and friction coefficient and Skempton's coefficient need to be exhaustively considered. In this paper, we specifically explore the uncertainty in slip models of the source fault of the 2011 Mw 9.0 Tohoku-oki earthquake as a case study. This earthquake was chosen because of its wealth of finite-fault slip models. Based on the wealth of those slip models, we compute the coseismic Coulomb stress changes induced by this mainshock. Our results indicate that nearby Coulomb stress changes for each slip model can be quite different, both for the Coulomb stress map at a given depth and on the Pacific subducting slab. The triggering rates for three months of aftershocks of the mainshock, with and without considering the uncertainty in slip models, differ significantly, decreasing from 70% to 18%. Reliable Coulomb stress changes in the three seismogenic zones of Nanki, Tonankai and Tokai are insignificant, approximately only 0.04 bar. By contrast, the portions of the Pacific subducting slab at a depth of 80 km and beneath Tokyo received a positive Coulomb stress change of approximately 0.2 bar. The standard errors of the seismicity rate and earthquake probability based on the Coulomb rate-and-state model (CRS) decay much faster with elapsed time in stress triggering zones than in stress shadows, meaning that the uncertainties in Coulomb stress changes in stress triggering zones would not drastically affect assessments of the seismicity rate and earthquake probability based on the CRS in the intermediate to long term.

  8. Study on seismic stability of seawall in man-made island. Pt. 5. Deformation of actual seawall during earthquake and estimation of seismic performance

    International Nuclear Information System (INIS)

    Kanatani, Mamoru; Tochigi, Hitoshi; Kawai, Tadashi; Sakakiyama, Tsutomu; Kudo, Koji

    1999-01-01

    In the development of the man-made island siting technology of nuclear power plants, assessing the stability of the seawall against large ocean waves and earthquakes is indispensable. Concerning the seismic stability of the seawall, prediction of the deformation of the seawall during earthquake is important to evaluate the seismic performance of the seawall after the earthquake. In the this report, the deformation of the actual seawall was predicted from the results of the centrifuge model tests and the case studies by the numerical analyses. Furthermore, wave flume model tests of the seawall with the deformed armour embankment by the earthquake shaking were conducted to investigate the effects of the deformation of the armoured embankment to the overtopping discharge by the waves. Obtained results were as follows: (1) It was experimentally confirmed that the slope gentleness and the decrease of the top elevation of the armoured embankment induced by the earthquake did not lead to the increase of the overtopping discharge by the waves after the earthquake. (2) Subsidence and lateral displacement at the top of the parapet of the seawall caused by the S2 scale earthquake were approximately 0.12 m-0.2 m and 0.18 m-0.6 m respectively under the condition that the thickness of the sand seabed was 10 m and relative density was 60%. (3) Even though such displacements were induced at the top of the parapet of the seawall, seismic performance of the seawall against the large waves was kept after the earthquake. (author)

  9. The Alaska earthquake, March 27, 1964: lessons and conclusions

    Science.gov (United States)

    Eckel, Edwin B.

    1970-01-01

    local waves. Better earthquake-hazard maps, based on improved knowledge of regional geology, fault behavior, and earthquake mechanisms, are needed for the entire country. Their preparation will require the close collaboration of engineers, seismologists, and geologists. Geologic maps of all inhabited places in earthquake-prone parts of the country are also needed by city planners and others, because the direct relationship between local geology and potential earthquake damage is now well understood. Improved and enlarged nets of earthquake-sensing instruments, sited in relation to known geology, are needed, as are many more geodetic and hydrographic measurements. Every large earthquake, wherever located, should be regarded as a full-scale laboratory experiment whose study can give scientific and engineering information unobtainable from any other source. Plans must be made before the event to insure staffing, funding, and coordination of effort for the scientific and engineering study of future earthquakes. Advice of earth scientists and engineers should be used in the decision-making processes involved in reconstruction after any future disastrous earthquake, as was done after the Alaska earthquake. The volume closes with a selected bibliography and a comprehensive index to the entire series of U.S. Geological Survey Professional Papers 541-546. This is the last in a series of six reports that the U.S. Geological Survey published on the results of a comprehensive geologic study that began, as a reconnaissance survey, within 24 hours after the March 27, 1964, Magnitude 9.2 Great Alaska Earthquake and extended, as detailed investigations, through several field seasons. The 1964 Great Alaska earthquake was the largest earthquake in the U.S. since 1700. Professional Paper 546, in 1 part, describes Lessons and Conclusions.

  10. Performance of precast buildings during Emilia-Romagna earthquakes: a case study

    OpenAIRE

    Ercolino, Marianna; Magliulo, Gennaro; Manfredi, Gaetano

    2015-01-01

    On May 2012 two earthquakes occurred in Emilia-Romagna region (Italy) causing several damages to existing industrial precast structures. These damages were mainly due to inadequate connection systems and the main recorded failures were the loss of support of structural elements due to the sliding of friction connections. This paper aims at justifying some of these damages by investigating the response of a real industrial building, located in Mirandola (Modena, Italy) and seriously damaged af...

  11. A global outer-rise/outer-trench-slope (OR/OTS) earthquake study

    Science.gov (United States)

    Wartman, J. M.; Kita, S.; Kirby, S. H.; Choy, G. L.

    2009-12-01

    Using improved seismic, bathymetric, satellite gravity and other geophysical data, we investigated the seismicity patterns and focal mechanisms of earthquakes in oceanic lithosphere off the trenches of the world that are large enough to be well recorded at teleseismic distances. A number of prominent trends are apparent, some of which have been previously recognized based on more limited data [1], and some of which are largely new [2-5]: (1) The largest events and the highest seismicity rates tend to occur where Mesozoic incoming plates are subducting at high rates (e.g., those in the western Pacific and the Banda segment of Indonesia). The largest events are predominantly shallow normal faulting (SNF) earthquakes. Less common are reverse-faulting (RF) events that tend to be deeper and to be present along with SNF events where nearby seamounts, seamount chains and other volcanic features are subducting [Seno and Yamanaka, 1996]. Blooms of SNF OR/OTS events usually occur just after and seaward of great interplate thrust (IPT) earthquakes but are far less common after smaller IPT events. (2) Plates subducting at slow rates (Chile, the Ninety East Ridge in Sumatra, and the D’Entrecastaux Ridge in Vanuatu).

  12. Application of Incremental Dynamic Analysis (IDA Method for Studying the Dynamic Behavior of Structures During Earthquakes

    Directory of Open Access Journals (Sweden)

    M. Javanpour

    2017-02-01

    Full Text Available Prediction of existing buildings’ vulnerability by future earthquakes is one of the most essential topics in structural engineering. Modeling steel structures is a giant step in determining the damage caused by the earthquake, as such structures are increasingly being used in constructions. Hence, two same-order steel structures with two types of structural systems were selected (coaxial moment frames and moment frame. In most cases, a specific structure needs to satisfy several functional levels. For this purpose, a method is required to determine the input request to the structures under possible earthquakes. Therefore, the Incremental Dynamic Analysis (IDA was preferred to the Push-Over non-linear static method for the analysis and design of the considered steel structures, due its accuracy and effect of higher modes at the same time intervals. OpenSees software was used to perform accurate nonlinear analysis of the steel structure. Two parameters (spectral acceleration and maximum ground acceleration were introduced to the modeled frames to compare the numerical correlations of seismic vulnerability obtained by two statistical methods based on the "log-normal distribution" and "logistics distribution", and finally, the parameters of displacement and drift were assessed after analysis.

  13. Earthquake experience interference effects in a modified Stroop task: an ERP study.

    Science.gov (United States)

    Wei, Dongtao; Qiu, Jiang; Tu, Shen; Tian, Fang; Su, Yanhua; Luo, Yuejia

    2010-05-03

    The effects of the modified Stroop task on ERP were investigated in 20 subjects who had experienced the Sichuan earthquake and a matched control group. ERP data showed that Incongruent stimuli elicited a more negative ERP deflection (N300-450) than did Congruent stimuli between 300 and 450 ms post-stimulus in the earthquake group but not found in the control group, and the N300-450 might reflect conflict monitor (the information of color and meaning do not match) in the early phase of perception identification due to their sensitivity to the external stimulus. Then, Incongruent stimuli elicited a more negative ERP deflection than did Congruent stimuli between 450 and 650 ms post-stimulus in both the groups. Dipole source analysis showed that the N450-650 was mainly generated in the ACC contributed to this effect in the control group, which might be related to monitor and conflict resolution. However, in the earthquake group, the N450-650 was generated in the thalamus, which might be involved in inhibiting and compensating of the ACC which may be related to conflict resolution process. 2010 Elsevier Ireland Ltd. All rights reserved.

  14. Assessing earthquake early warning using sparse networks in developing countries: Case study of the Kyrgyz Republic

    Science.gov (United States)

    Parolai, Stefano; Boxberger, Tobias; Pilz, Marco; Fleming, Kevin; Haas, Michael; Pittore, Massimiliano; Petrovic, Bojana; Moldobekov, Bolot; Zubovich, Alexander; Lauterjung, Joern

    2017-09-01

    The first real-time digital strong-motion network in Central Asia has been installed in the Kyrgyz Republic since 2014. Although this network consists of only 19 strong-motion stations, they are located in near-optimal locations for earthquake early warning and rapid response purposes. In fact, it is expected that this network, which utilizes the GFZ-Sentry software, allowing decentralized event assessment calculations, not only will provide useful strong motion data useful for improving future seismic hazard and risk assessment, but will serve as the backbone for regional and on-site earthquake early warning operations. Based on the location of these stations, and travel-time estimates for P- and S-waves, we have determined potential lead times for several major urban areas in Kyrgyzstan (i.e., Bishkek, Osh, and Karakol) and Kazakhstan (Almaty), where we find the implementation of an efficient earthquake early warning system would provide lead times outside the blind zone ranging from several seconds up to several tens of seconds. This was confirmed by the simulation of the possible shaking (and intensity) that would arise considering a series of scenarios based on historical and expected events, and how they affect the major urban centres. Such lead times would allow the instigation of automatic mitigation procedures, while the system as a whole would support prompt and efficient actions to be undertaken over large areas.

  15. Effects of earthquakes on the deep repository for spent fuel in Sweden based on case studies and preliminary model results

    International Nuclear Information System (INIS)

    Baeckblom, Goeran; Munier, Raymond

    2002-06-01

    their original values within a few months. The density of the buffer around the canister is high enough to prevent liquefaction due to shaking. The predominant brittle deformation of a rock mass will be reactivation of pre- existing fractures. The ata emanating from faults intersecting tunnels show that creation of new fractures is confined to the immediate vicinity of the reactivated faults and that deformation in host rock is rapidly decreasing with the distance from the fault. By selection of appropriate respect distances the probability of canister damage due to faulting is further lowered. Data from deep South African mines show that rocks in a environment with non- existing faults and with low fracture densities and high stresses might generate faults in a previously unfractured rock mass. The Swedish repository will be located in fractured bedrock, at intermediate depth, 400 - 700 m, where stresses are moderate. The conditions to create these peculiar mining-induced features will not prevail in the repository environment. Should these faults anyhow be created, the canister is designed to withstand a shear deformation of at least 0.1 m. This corresponds to a magnitude 6 earthquake along the fault with a length of at least 1 km which is highly unlikely. Respect distance has to be site and fault specific. Field evidence gathered in this study indicates that respect distances may be considerably smaller (tens to hundreds of m) than predicted by numerical modelling (thousands of m). However, the accumulated deformation during repeated, future seismic event has to be accounted for

  16. Automatic recognition of seismic intensity based on RS and GIS: a case study in Wenchuan Ms8.0 earthquake of China.

    Science.gov (United States)

    Zhang, Qiuwen; Zhang, Yan; Yang, Xiaohong; Su, Bin

    2014-01-01

    In recent years, earthquakes have frequently occurred all over the world, which caused huge casualties and economic losses. It is very necessary and urgent to obtain the seismic intensity map timely so as to master the distribution of the disaster and provide supports for quick earthquake relief. Compared with traditional methods of drawing seismic intensity map, which require many investigations in the field of earthquake area or are too dependent on the empirical formulas, spatial information technologies such as Remote Sensing (RS) and Geographical Information System (GIS) can provide fast and economical way to automatically recognize the seismic intensity. With the integrated application of RS and GIS, this paper proposes a RS/GIS-based approach for automatic recognition of seismic intensity, in which RS is used to retrieve and extract the information on damages caused by earthquake, and GIS is applied to manage and display the data of seismic intensity. The case study in Wenchuan Ms8.0 earthquake in China shows that the information on seismic intensity can be automatically extracted from remotely sensed images as quickly as possible after earthquake occurrence, and the Digital Intensity Model (DIM) can be used to visually query and display the distribution of seismic intensity.

  17. Automatic Recognition of Seismic Intensity Based on RS and GIS: A Case Study in Wenchuan Ms8.0 Earthquake of China

    Directory of Open Access Journals (Sweden)

    Qiuwen Zhang

    2014-01-01

    Full Text Available In recent years, earthquakes have frequently occurred all over the world, which caused huge casualties and economic losses. It is very necessary and urgent to obtain the seismic intensity map timely so as to master the distribution of the disaster and provide supports for quick earthquake relief. Compared with traditional methods of drawing seismic intensity map, which require many investigations in the field of earthquake area or are too dependent on the empirical formulas, spatial information technologies such as Remote Sensing (RS and Geographical Information System (GIS can provide fast and economical way to automatically recognize the seismic intensity. With the integrated application of RS and GIS, this paper proposes a RS/GIS-based approach for automatic recognition of seismic intensity, in which RS is used to retrieve and extract the information on damages caused by earthquake, and GIS is applied to manage and display the data of seismic intensity. The case study in Wenchuan Ms8.0 earthquake in China shows that the information on seismic intensity can be automatically extracted from remotely sensed images as quickly as possible after earthquake occurrence, and the Digital Intensity Model (DIM can be used to visually query and display the distribution of seismic intensity.

  18. Post-Traumatic Stress Symptoms and Burnout Among Medical Rescue Workers 4 Years After the Great East Japan Earthquake: A Longitudinal Study.

    Science.gov (United States)

    Kawashima, Yuzuru; Nishi, Daisuke; Noguchi, Hiroko; Usuki, Masato; Yamashita, Akihiro; Koido, Yuichi; Okubo, Yoshiro; Matsuoka, Yutaka J

    2016-12-01

    This study aimed to evaluate factors associated with post-traumatic stress disorder (PTSD) symptoms and burnout 4 years after the Great East Japan Earthquake among medical rescue workers in Disaster Medical Assistance Teams (DMATs). We examined participants' background characteristics, prior health condition, rescue work experiences, and the Peritraumatic Distress Inventory (PDI) score at 1 month after the earthquake. Current psychological condition was assessed by the Impact of Event Scale-Revised and Maslach Burnout Inventory administered 4 years after the earthquake. By applying univariate and multivariate linear regression analyses, we assessed the relative value of the PDI and other baseline variables for PTSD symptoms and burnout at 4 years after the earthquake. We obtained baseline data from 254 participants during April 2 to 22, 2011. Of the 254 participants, 188 (74.0%) completed the follow-up assessment. PDI score 1 month after the earthquake was associated with symptoms of PTSD (β=0.35, Pburnout (β=0.21, PStress before deployment was a related factor for burnout 4 years after the earthquake in these medical rescue workers (β=2.61, Pstress prior to deployment (Disaster Med Public Health Preparedness. 2016;10:848-853).

  19. Application of instrumented nanoindentation in preformulation studies of pharmaceutical active ingredients and excipients

    Directory of Open Access Journals (Sweden)

    Egart Mateja

    2016-09-01

    Full Text Available Nanoindentation allows quantitative determination of a material’s response to stress such as elastic and plastic deformation or fracture tendency. Key instruments that have enabled great advances in nanomechanical studies are the instrumented nanoindenter and atomic force microscopy. The versatility of these instruments lies in their capability to measure local mechanical response, in very small volumes and depths, while monitoring time, displacement and force with high accuracy and precision.

  20. Prevalence and psychosocial risk factors of PTSD: 18 months after Kashmir earthquake in Pakistan.

    Science.gov (United States)

    Naeem, Farooq; Ayub, Muhammad; Masood, Khadija; Gul, Huma; Khalid, Mahwish; Farrukh, Ammara; Shaheen, Aisha; Waheed, Waquas; Chaudhry, Haroon Rasheed

    2011-04-01

    On average in a year 939 earthquakes of a magnitude between 5 and 8 on the Richter scale occur around the world. In earthquakes developing countries are prone to large-scale destruction because of poor structural quality of buildings, and preparedness for earthquakes. On 8th October 2005, a major earthquake hit the remote and mountainous region of northern Pakistan and Kashmir. We wanted to find out the rate of PTSD in a randomly selected sample of participants living in earthquake area and the correlates of the PTSD. The study was conducted 18 months after the earthquake. We selected a sample of men and women living in the houses and tents for interviews. Using well established instruments for PTSD and general psychiatric morbidity we gathered information from over 1200 people in face to face interviews. We gathered information about trauma exposure and loss as well. 55.2% women and 33.4% men suffered from PTSD. Living in a joint family was protective against the symptoms of PTSD. Dose of exposure to trauma was associated with the symptoms of PTSD. Living in a tent was associated with general psychiatric morbidity but not with PTSD. We used questionnaire instead of interviews to detect the symptoms of psychiatric disorders. The symptoms of PTSD are common 18 months after the earthquake and they are specifically associated with the dose of trauma exposure. This may have implications for rehabilitation of this population. Copyright © 2010 Elsevier B.V. All rights reserved.

  1. Archiving, sharing, processing and publishing historical earthquakes data: the IT point of view

    Science.gov (United States)

    Locati, Mario; Rovida, Andrea; Albini, Paola

    2014-05-01

    Digital tools devised for seismological data are mostly designed for handling instrumentally recorded data. Researchers working on historical seismology are forced to perform their daily job using a general purpose tool and/or coding their own to address their specific tasks. The lack of out-of-the-box tools expressly conceived to deal with historical data leads to a huge amount of time lost in performing tedious task to search for the data and, to manually reformat it in order to jump from one tool to the other, sometimes causing a loss of the original data. This reality is common to all activities related to the study of earthquakes of the past centuries, from the interpretations of past historical sources, to the compilation of earthquake catalogues. A platform able to preserve the historical earthquake data, trace back their source, and able to fulfil many common tasks was very much needed. In the framework of two European projects (NERIES and SHARE) and one global project (Global Earthquake History, GEM), two new data portals were designed and implemented. The European portal "Archive of Historical Earthquakes Data" (AHEAD) and the worldwide "Global Historical Earthquake Archive" (GHEA), are aimed at addressing at least some of the above mentioned issues. The availability of these new portals and their well-defined standards makes it easier than before the development of side tools for archiving, publishing and processing the available historical earthquake data. The AHEAD and GHEA portals, their underlying technologies and the developed side tools are presented.

  2. Interactions between strike-slip earthquakes and the subduction interface near the Mendocino Triple Junction

    Science.gov (United States)

    Gong, Jianhua; McGuire, Jeffrey J.

    2018-01-01

    The interactions between the North American, Pacific, and Gorda plates at the Mendocino Triple Junction (MTJ) create one of the most seismically active regions in North America. The earthquakes rupture all three plate boundaries but also include considerable intraplate seismicity reflecting the strong internal deformation of the Gorda plate. Understanding the stress levels that drive these ruptures and estimating the locking state of the subduction interface are especially important topics for regional earthquake hazard assessment. However owing to the lack of offshore seismic and geodetic instruments, the rupture process of only a few large earthquakes near the MTJ have been studied in detail and the locking state of the subduction interface is not well constrained. In this paper, first, we use the second moments inversion method to study the rupture process of the January 28, 2015 Mw 5.7 earthquake on the Mendocino transform fault that was unusually well recorded by both onshore and offshore strong motion instruments. We estimate the rupture dimension to be approximately 6 km by 3 km corresponding to a stress drop of ∼4 MPa for a crack model. Next we investigate the frictional state of the subduction interface by simulating the afterslip that would be expected there as a result of the stress changes from the 2015 earthquake and a 2010 Mw 6.5 intraplate earthquake within the subducted Gorda plate. We simulate afterslip scenarios for a range of depths of the downdip end of the locked zone defined as the transition to velocity strengthening friction and calculate the corresponding surface deformation expected at onshore GPS monuments. We can rule out a very shallow downdip limit owing to the lack of a detectable signal at onshore GPS stations following the 2010 earthquake. Our simulations indicate that the locking depth on the slab surface is at least 14 km, which suggests that the next M8 earthquake rupture will likely reach the coastline and strong shaking

  3. The music of earthquakes and Earthquake Quartet #1

    Science.gov (United States)

    Michael, Andrew J.

    2013-01-01

    Earthquake Quartet #1, my composition for voice, trombone, cello, and seismograms, is the intersection of listening to earthquakes as a seismologist and performing music as a trombonist. Along the way, I realized there is a close relationship between what I do as a scientist and what I do as a musician. A musician controls the source of the sound and the path it travels through their instrument in order to make sound waves that we hear as music. An earthquake is the source of waves that travel along a path through the earth until reaching us as shaking. It is almost as if the earth is a musician and people, including seismologists, are metaphorically listening and trying to understand what the music means.

  4. Advancing Understanding of Earthquakes by Drilling an Eroding Convergent Margin

    Science.gov (United States)

    von Huene, R.; Vannucchi, P.; Ranero, C. R.

    2010-12-01

    A program of IODP with great societal relevance is sampling and instrumenting the seismogenic zone. The zone generates great earthquakes that trigger tsunamis, and submarine slides thereby endangering coastal communities containing over sixty percent of the earth’s population. To asses and mitigate this endangerment it is urgent to advance understanding of fault dynamics that allows more timely anticipation of hazardous seismicity. Seismogenesis on accreting and eroding convergent plate boundaries apparently differ because of dissimilar materials along the interplate fault. As the history of instrumentally recorded earthquakes expands the difference becomes clearer. The more homogeneous clay, silt and sand subducted at accreting margins is associated with great earthquakes (M 9) whereas the fragmented upper plate rock that can dominate subducted material along an eroding margin plate interface is associated with many tsunamigenic earthquakes (Bilek, 2010). Few areas have been identified where the seismogenic zone can be reached with scientific drilling. In IODP accreting margins are studied on the NanTroSeize drill transect off Japan where the ultimate drilling of the seismogenic interface may occur by the end of IODP. The eroding Costa Rica margin will be studied in CRISP where a drill program will begin in 2011. The Costa Rican geophysical site survey will be complete with acquisition and processing of 3D seismic data in 2011 but the entire drilling will not be accomplished in IODP. It is appropriate that the accreting margin study be accomplished soon considering the indications of a pending great earthquake that will affect a country that has devoted enormous resources to IODP. However, understanding the erosional end-member is scientifically as important to an understanding of fault mechanics. Transoceanic tsunamis affect the entire Pacific rim where most subduction zones are eroding margins. The Costa Rican subduction zone is less complex operationally and

  5. State-of-the-art of historical earthquake research in Fennoscandia and the Baltic Republics

    Directory of Open Access Journals (Sweden)

    V. Nikulin

    2004-06-01

    Full Text Available We review historical earthquake research in Northern Europe. 'Historical' is defined as being identical with seismic events occurring in the pre-instrumental and early instrumental periods between 1073 and the mid-1960s. The first seismographs in this region were installed in Uppsala, Sweden and Bergen, Norway in 1904-1905, but these mechanical pendulum instruments were broad band and amplification factors were modest at around 500. Until the 1960s few modern short period electromagnetic seismographs were deployed. Scientific earthquake studies in this region began during the first decades of the 1800s, while the systematic use of macroseismic questionnaires commenced at the end of that century. Basic research efforts have vigorously been pursued from the 1970s onwards because of the mandatory seismic risk studies for commissioning nuclear power plants in Sweden, Finland, NW Russia, Kola and installations of huge oil platforms in the North Sea. The most comprehensive earthquake database currently available for Northern Europe is the FENCAT catalogue covering about six centuries and representing the accumulation of work conducted by many scientists during the last 200 years. This catalogue is given in parametric form, while original macroseismic observations and intensity maps for the largest earthquakes can be found in various national publications, often in local languages. No database giving intensity data points exists in computerized form for the region. The FENCAT catalogue still contains some spurious events of various kinds but more serious are some recent claims that some of the presumed largest historical earthquakes have been assigned too large magnitude values, which would have implications for earthquake hazard levels implemented in national building codes. We discuss future cooperative measures such as establishing macroseismic data archives as a means for promoting further research on historical earthquakes in Northern Europe.

  6. Connecting slow earthquakes to huge earthquakes.

    Science.gov (United States)

    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. Copyright © 2016, American Association for the Advancement of Science.

  7. What Can Sounds Tell Us About Earthquake Interactions?

    Science.gov (United States)

    Aiken, C.; Peng, Z.

    2012-12-01

    It is important not only for seismologists but also for educators to effectively convey information about earthquakes and the influences earthquakes can have on each other. Recent studies using auditory display [e.g. Kilb et al., 2012; Peng et al. 2012] have depicted catastrophic earthquakes and the effects large earthquakes can have on other parts of the world. Auditory display of earthquakes, which combines static images with time-compressed sound of recorded seismic data, is a new approach to disseminating information to a general audience about earthquakes and earthquake interactions. Earthquake interactions are influential to understanding the underlying physics of earthquakes and other seismic phenomena such as tremors in addition to their source characteristics (e.g. frequency contents, amplitudes). Earthquake interactions can include, for example, a large, shallow earthquake followed by increased seismicity around the mainshock rupture (i.e. aftershocks) or even a large earthquake triggering earthquakes or tremors several hundreds to thousands of kilometers away [Hill and Prejean, 2007; Peng and Gomberg, 2010]. We use standard tools like MATLAB, QuickTime Pro, and Python to produce animations that illustrate earthquake interactions. Our efforts are focused on producing animations that depict cross-section (side) views of tremors triggered along the San Andreas Fault by distant earthquakes, as well as map (bird's eye) views of mainshock-aftershock sequences such as the 2011/08/23 Mw5.8 Virginia earthquake sequence. These examples of earthquake interactions include sonifying earthquake and tremor catalogs as musical notes (e.g. piano keys) as well as audifying seismic data using time-compression. Our overall goal is to use auditory display to invigorate a general interest in earthquake seismology that leads to the understanding of how earthquakes occur, how earthquakes influence one another as well as tremors, and what the musical properties of these

  8. The Pliocene Horcón Formation, Central Chile: a case study of earthquake-induced landslide susceptibility

    Science.gov (United States)

    Valdivia, D.; Elgueta, S.; Hodgkin, A.; Marquardt, C.; del Valle, F.; Yáñez Morroni, G.

    2017-12-01

    Stability slope analysis is typically focused on modeling using cohesion and friction angle parameters but in earthquake-induced landslides, susceptibility is correlated more to lithological and stratigraphic parameters. In sedimentary deposits whose cohesion and diagenesis are very low, the risk of landslides increases. The Horcón Formation, which crops out continuously along cliffs in Central Chile between 32.5° and 33°S, is a Miocene-Pliocene well preserved, horizontally stratified unit composed of marine strata which overlies Paleozoic-Mesozoic igneous basement. During the Quaternary, the sequence was tectonically uplifted 80 meters and covered by unconsolidated eolian deposits. Given that Seismotectonic and Barrier-Asperity models suggest the occurrence of a forthcoming megathrust earthquake in a segment which includes this area, the Horcón Formation constitutes a good case study to characterize the susceptibility of this type of sediment for mass movements triggered by earthquakes. Field mapping, stratigraphic and sedimentological studies, including petrographic analyses to determine lithological composition and paragenesis of diagenetic events, have been carried out along with limited gravimetric profiling and CPTU drill tests. High resolution digital elevation modeling has also been applied. This work has led to the recognition of a shallow marine lithofacies association composed of weakly lithified fossiliferous and bioturbated medium to fine grained litharenite, mudstone, and fine conglomerate. The low grade of diagenesis in the sedimentary deposits was in response to a short period of burial and a subsequent accelerated uplift evidenced along the coast of Chile during the Quaternary. We have generated a predictive model of landslide susceptibility for the Horcón Formation and for the overlying Quaternary eolian deposits incorporating variables such as composition and diagenesis of lithofacies, slope, structures, weathering and landcover. The model

  9. Leveraging geodetic data to reduce losses from earthquakes

    Science.gov (United States)

    Murray, Jessica R.; Roeloffs, Evelyn A.; Brooks, Benjamin A.; Langbein, John O.; Leith, William S.; Minson, Sarah E.; Svarc, Jerry L.; Thatcher, Wayne R.

    2018-04-23

    analysis systems.Collaborate on research, development, and operation of affordable, high-precision seafloor geodetic methods that improve earthquake forecasting and event response.Advance computational techniques and instrumentation to enable use of strategies like repeat-pass imagery and low-cost geodetic sensors for earthquake response, monitoring, and research.Engage stakeholders and collaborate with partner institutions to foster operational and research objectives and to safeguard the continued health of geodetic infrastructure upon which we mutually depend.Maintaining a vibrant internal research program provides the foundation by which the EHP can remain an effective and trusted source for earthquake science. Exploiting abundant new data sources, evaluating and assimilating the latest science, and pursuing novel avenues of investigation are means to fulfilling the EHP’s core responsibilities and realizing the important scientific advances envisioned by its scientists. Central to the success of such a research program is engaging personnel with a breadth of competencies and a willingness and ability to adapt these to the program’s evolving priorities, enabling current staff to expand their skills and responsibilities, and planning holistically to meet shared workforce needs. In parallel, collaboration with external partners to support scientific investigations that complement ongoing internal research enables the EHP to strengthen earthquake information products by incorporating alternative perspectives and approaches and to study topics and geographic regions that cannot be adequately covered internally.With commensurate support from technical staff who possess diverse skills, including engineering, information technology, and proficiency in quantitative analysis combined with basic geophysical knowledge, the EHP can achieve the geodetic outcomes identified in this document.

  10. FMIT test-end instrumentation systems scoping study

    International Nuclear Information System (INIS)

    Fuller, J.L.; Dixon, N.E.; Sheen, E.M.

    1982-06-01

    For the Fusion Materials Irradiation Test facility (FMIT), the high power density of the accelerated deuteron beam and the unique nature of the liquid lithium target underscore the need for sensitive, fast and reliable test-end diagnostic instrumentation. The intense radiation environment in the test cell places severe limits on candidate systems, as to a lesser degree do thermal and lithium compatibility factors. A beam-target diagnostic station at 180 in the HEBT can facilitate source emission and spot-on-target imaging. Analyses support the feasibility of several candidate imaging systems. Incorporation of electromagnetic and electrostatic beam position detectors as part of the target assembly, as previously proposed, should also be feasible. The possibilities for on-line, real-time ultrasonic/acoustic target diagnosis are favorable. The use of redundant thermocouple and ion detector test assembly beam location detectors is also supported because of the possible problems with thermocouples in the intense 14-MeV neutron field and the simplicity of the ion detectors

  11. Web-based Tsunami Early Warning System: a case study of the 2010 Kepulaunan Mentawai Earthquake and Tsunami

    Directory of Open Access Journals (Sweden)

    E. Ulutas

    2012-06-01

    Full Text Available This study analyzes the response of the Global Disasters Alerts and Coordination System (GDACS in relation to a case study: the Kepulaunan Mentawai earthquake and related tsunami, which occurred on 25 October 2010. The GDACS, developed by the European Commission Joint Research Center, combines existing web-based disaster information management systems with the aim to alert the international community in case of major disasters. The tsunami simulation system is an integral part of the GDACS. In more detail, the study aims to assess the tsunami hazard on the Mentawai and Sumatra coasts: the tsunami heights and arrival times have been estimated employing three propagation models based on the long wave theory. The analysis was performed in three stages: (1 pre-calculated simulations by using the tsunami scenario database for that region, used by the GDACS system to estimate the alert level; (2 near-real-time simulated tsunami forecasts, automatically performed by the GDACS system whenever a new earthquake is detected by the seismological data providers; and (3 post-event tsunami calculations using GCMT (Global Centroid Moment Tensor fault mechanism solutions proposed by US Geological Survey (USGS for this event. The GDACS system estimates the alert level based on the first type of calculations and on that basis sends alert messages to its users; the second type of calculations is available within 30–40 min after the notification of the event but does not change the estimated alert level. The third type of calculations is performed to improve the initial estimations and to have a better understanding of the extent of the possible damage. The automatic alert level for the earthquake was given between Green and Orange Alert, which, in the logic of GDACS, means no need or moderate need of international humanitarian assistance; however, the earthquake generated 3 to 9 m tsunami run-up along southwestern coasts of the Pagai Islands where 431 people died

  12. The strong motion amplitudes from Himalayan earthquakes and a pilot study for the deterministic first order microzonation of Delhi City

    International Nuclear Information System (INIS)

    Parvez, Imtiyaz A.; Panza, G.F.; Gusev, A.A.; Vaccari, F.

    2001-09-01

    The interdependence among the strong-motion amplitude, earthquake magnitude and hypocentral distance has been established (Parvez et al. 2001) for the Himalayan region using the dataset of six earthquakes, two from Western and four from Eastern Himalayas (M w =5.2-7.2) recorded by strong-motion networks in the Himalayas. The level of the peak strong motion amplitudes in the Eastern Himalayas is three fold larger than that in the Western Himalayas, in terms of both peak acceleration and peak velocities. In the present study, we include the strong motion data of Chamoli earthquake (M w =6.5) of 1999 from the western sub-region to see whether this event supports the regional effects and we find that the new result fits well with our earlier prediction in the Western Himalayas. The minimum estimates of peak acceleration for the epicentral zone of M w =7.5-8.5 events is A peak =0.25-0.4 g for the Western Himalayas and as large as A peak =1.0-1.6 g for the Eastern Himalayas. Similarly, the expected minimum epicentral values of V peak for M w =8 are 35 cm/s for Western and 112 cm/s for Eastern Himalayas. The presence of unusually high levels of epicentral amplitudes for the eastern subregion also agrees well with the macroseismic evidence (Parvez et al. 2001). Therefore, these results represent systematic regional effects, and may be considered as a basis for future regionalized seismic hazard assessment in the Himalayan region. Many metropolitan and big cities of India are situated in the severe hazard zone just south of the Himalayas. A detailed microzonation study of these sprawling urban centres is therefore urgently required for gaining a better understanding of ground motion and site effects in these cities. An example of the study of site effects and microzonation of a part of metropolitan Delhi is presented based on a detailed modelling along a NS cross sections from the Inter State Bus Terminal (ISBT) to Sewanagar. Full synthetic strong motion waveforms have been

  13. Long-Term Monitoring of the Impacts of Disaster on Human Activity Using DMSP/OLS Nighttime Light Data: A Case Study of the 2008 Wenchuan, China Earthquake

    Directory of Open Access Journals (Sweden)

    Xue Li

    2018-04-01

    Full Text Available Time series monitoring of earthquake-stricken areas is significant in evaluating post-disaster reconstruction and recovery. The time series of nighttime light (NTL data collected by the defense meteorological satellite program-operational linescan system (DMSP/OLS sensors provides a unique and valuable resource to study changes in human activity (HA because of the long period of available data. In this paper, the DMSP/OLS NTL images’ digital number (DN is used as a proxy for the intensity of HA since there is a high correlation between them. The purpose of this study is to develop a methodology to analyze the changes of intensity and distribution of HA in different areas affected by a 2008 earthquake in Wenchuan, China. In order to compare the trends of HA before and after the earthquake, the DMSP/OLS NTL images from 2003 to 2013 were processed and analyzed. However, their analysis capability is greatly limited owing to a lack of in-flight calibration. To improve the continuity and comparability of DMSP/OLS NTL images, this study developed an automatic intercalibration method to systematically correct NTL data. The results reveal that: (1 compared with the HA before the earthquake, the reconstruction and recovery of the Wenchuan earthquake have led to a significant increase of HA in earthquake-stricken areas within three years after the earthquake; (2 the fluctuation of HA in a severely-affected area is greater than that in a less-affected area; (3 recovery efforts increase development in the most affected areas to levels that exceeded the rates in similar areas which experienced less damage; and (4 areas alongside roads and close to reconstruction projects exhibited increased development in regions with otherwise low human activity.

  14. Twitter earthquake detection: earthquake monitoring in a social world

    Directory of Open Access Journals (Sweden)

    Daniel C. Bowden

    2011-06-01

    Full Text Available 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 USGS earthquake response products and the delivery of hazard information. Rapid detection and qualitative assessment of shaking events are possible because people begin sending public Twitter messages (tweets with in tens of seconds after feeling shaking. Here we present and evaluate an earthquake detection procedure that relies solely on Twitter data. A tweet-frequency time series constructed from tweets containing the word “earthquake” clearly shows large peaks correlated with the origin times of widely felt events. To identify possible earthquakes, we use a short-term-average, long-term-average algorithm. When tuned to a moderate sensitivity, the detector finds 48 globally-distributed earthquakes with only two false triggers in five months of data. The number of detections is small compared to the 5,175 earthquakes in the USGS global earthquake catalog for the same five-month time period, and no accurate location or magnitude can be assigned based on tweet data alone. However, Twitter earthquake detections are not without merit. The detections are generally caused by widely felt events that are of more immediate interest than those with no human impact. The detections are also fast; about 75% occur within two minutes of the origin time. This is considerably faster than seismographic detections in poorly instrumented regions of the world. The tweets triggering the detections also provided very short first-impression narratives from people who experienced the shaking.

  15. Geostationary Coastal and Air Pollution Events (GEO CAPE) Instrument Performance Study

    Science.gov (United States)

    Mannino, Antonio; Hartman, Kathy R.

    2014-01-01

    The Ultimate objective of the GEO-CAPE 2014 study: Quantify the cost impact of very specific changes in instrument performance! The customer has defined 4 instrument types they are notionally interested in:! FR: Filter Radiometer! WAS: Wide Angle Spectrometer! MSS: Multi Slit Spectrometer! SSS: Single Slit Spectrometer.

  16. Risk Assessment Stability: A Revalidation Study of the Arizona Risk/Needs Assessment Instrument

    Science.gov (United States)

    Schwalbe, Craig S.

    2009-01-01

    The actuarial method is the gold standard for risk assessment in child welfare, juvenile justice, and criminal justice. It produces risk classifications that are highly predictive and that may be robust to sampling error. This article reports a revalidation study of the Arizona Risk/Needs Assessment instrument, an actuarial instrument for juvenile…

  17. The Impact of Instrumental Music Learning on Attainment at Age 16: A Pilot Study

    Science.gov (United States)

    Hallam, Susan; Rogers, Kevin

    2016-01-01

    There is increasing international evidence that playing a musical instrument has a positive impact on attainment at school but little research has been undertaken in the UK. This study addresses this drawing on data on attainment at age 11 and 16 relating to 608 students, 115 of whom played a musical instrument. The fndings showed that the young…

  18. Feasibility study on earthquake early warning application to schools: the example of the ITIS 'E. Majorana', Somma Vesuviana, Naples (Italy)

    Science.gov (United States)

    Emolo, Antonio; Zollo, Aldo; Picozzi, Matteo; Martino, Claudio; Elia, Luca; Verderame, Gerardo; De Risi, Maria Teresa; Ricci, Paolo; Lombardi, Anna; Bindi, Dino; Parolai, Stefano; Boxberger, Tobias; Miranda, Nicola

    2014-05-01

    One of the main objective of the WP7 (Strategic Applications and Capacity Building) in the framework of the REAKT-Strategies and tools for Real Time Earthquake RisK ReducTion FP7 European project, is to evaluate the effectiveness of EEW and real-time risk assessment procedures in reducing seismic risk to various industrial partners and end-users. In the context of the REAKT project, the AMRA-RISSCLab group is engaged in a feasibility study on the application of earthquake early-warning procedures in two high schools located in the Irpinia region (South Italy), an area that in the 1980 was struck by a magnitude 6.9 earthquake. In this work we report on the activities carried out during the last 24 Months at the school ITIS 'E. Majorana', located in Somma Vesuviana, a village in the neighbourhood of Naples. In order to perform a continuous seismic monitoring of the site, which includes a rather complex structure building, 5 accelerometric stations have been installed in different part of the school. In particular, a 24-bit ADC (Sigma/Delta) Agecodagis-Kefren data-logger has been installed with a Guralp CMG-5TC accelerometer with a 0.25g full-scale in the school courtyard, while 4 SOSEWIN sensors have been also installed at different locations within the building. Commercial ADSL lines provide transmission of real-time data to the EEW centre. Data streams are now acquired in real-time in the PRESToPlus (regional and on-site, threshold-based early-warning) software platform [1]. The recent December 29, 2013 M 5.1 Monti del Matese Earthquake, gave us the unique opportunity to use real strong motion data to test the performance of threshold-based early warning method at the school. The on-site method [2] aims to define alert levels at the monitored site. In particular, at each station the characteristic P-waves period (τc) and the peak displacement (Pd) are measured on the initial P-wave signal. They are compared with threshold values, previously established through an

  19. ECLSS Integration Analysis: Advanced ECLSS Subsystem and Instrumentation Technology Study for the Space Exploration Initiative

    Science.gov (United States)

    1990-01-01

    In his July 1989 space policy speech, President Bush proposed a long range continuing commitment to space exploration and development. Included in his goals were the establishment of permanent lunar and Mars habitats and the development of extended duration space transportation. In both cases, a major issue is the availability of qualified sensor technologies for use in real-time monitoring and control of integrated physical/chemical/biological (p/c/b) Environmental Control and Life Support Systems (ECLSS). The purpose of this study is to determine the most promising instrumentation technologies for future ECLSS applications. The study approach is as follows: 1. Precursor ECLSS Subsystem Technology Trade Study - A database of existing and advanced Atmosphere Revitalization (AR) and Water Recovery and Management (WRM) ECLSS subsystem technologies was created. A trade study was performed to recommend AR and WRM subsystem technologies for future lunar and Mars mission scenarios. The purpose of this trade study was to begin defining future ECLSS instrumentation requirements as a precursor to determining the instrumentation technologies that will be applicable to future ECLS systems. 2. Instrumentation Survey - An instrumentation database of Chemical, Microbial, Conductivity, Humidity, Flowrate, Pressure, and Temperature sensors was created. Each page of the sensor database report contains information for one type of sensor, including a description of the operating principles, specifications, and the reference(s) from which the information was obtained. This section includes a cursory look at the history of instrumentation on U.S. spacecraft. 3. Results and Recommendations - Instrumentation technologies were recommended for further research and optimization based on a consideration of both of the above sections. A sensor or monitor technology was recommended based on its applicability to future ECLS systems, as defined by the ECLSS Trade Study (1), and on whether its

  20. Defeating Earthquakes

    Science.gov (United States)

    Stein, R. S.

    2012-12-01

    The 2004 M=9.2 Sumatra earthquake claimed what seemed an unfathomable 228,000 lives, although because of its size, we could at least assure ourselves that it was an extremely rare event. But in the short space of 8 years, the Sumatra quake no longer looks like an anomaly, and it is no longer even the worst disaster of the Century: 80,000 deaths in the 2005 M=7.6 Pakistan quake; 88,000 deaths in the 2008 M=7.9 Wenchuan, China quake; 316,000 deaths in the M=7.0 Haiti, quake. In each case, poor design and construction were unable to withstand the ferocity of the shaken earth. And this was compounded by inadequate rescue, medical care, and shelter. How could the toll continue to mount despite the advances in our understanding of quake risk? The world's population is flowing into megacities, and many of these migration magnets lie astride the plate boundaries. Caught between these opposing demographic and seismic forces are 50 cities of at least 3 million people threatened by large earthquakes, the targets of chance. What we know for certain is that no one will take protective measures unless they are convinced they are at risk. Furnishing that knowledge is the animating principle of the Global Earthquake Model, launched in 2009. At the very least, everyone should be able to learn what his or her risk is. At the very least, our community owes the world an estimate of that risk. So, first and foremost, GEM seeks to raise quake risk awareness. We have no illusions that maps or models raise awareness; instead, earthquakes do. But when a quake strikes, people need a credible place to go to answer the question, how vulnerable am I, and what can I do about it? The Global Earthquake Model is being built with GEM's new open source engine, OpenQuake. GEM is also assembling the global data sets without which we will never improve our understanding of where, how large, and how frequently earthquakes will strike, what impacts they will have, and how those impacts can be lessened by

  1. Sense of Community and Depressive Symptoms among Older Earthquake Survivors Following the 2008 Earthquake in Chengdu China

    Science.gov (United States)

    Li, Yawen; Sun, Fei; He, Xusong; Chan, Kin Sun

    2011-01-01

    This study examined the impact of an earthquake as well as the role of sense of community as a protective factor against depressive symptoms among older Chinese adults who survived an 8.0 magnitude earthquake in 2008. A household survey of a random sample was conducted 3 months after the earthquake and 298 older earthquake survivors participated…

  2. Reading a 400,000-year record of earthquake frequency for an intraplate fault.

    Science.gov (United States)

    Williams, Randolph T; Goodwin, Laurel B; Sharp, Warren D; Mozley, Peter S

    2017-05-09

    Our understanding of the frequency of large earthquakes at timescales longer than instrumental and historical records is based mostly on paleoseismic studies of fast-moving plate-boundary faults. Similar study of intraplate faults has been limited until now, because intraplate earthquake recurrence intervals are generally long (10s to 100s of thousands of years) relative to conventional paleoseismic records determined by trenching. Long-term variations in the earthquake recurrence intervals of intraplate faults therefore are poorly understood. Longer paleoseismic records for intraplate faults are required both to better quantify their earthquake recurrence intervals and to test competing models of earthquake frequency (e.g., time-dependent, time-independent, and clustered). We present the results of U-Th dating of calcite veins in the Loma Blanca normal fault zone, Rio Grande rift, New Mexico, United States, that constrain earthquake recurrence intervals over much of the past ∼550 ka-the longest direct record of seismic frequency documented for any fault to date. The 13 distinct seismic events delineated by this effort demonstrate that for >400 ka, the Loma Blanca fault produced periodic large earthquakes, consistent with a time-dependent model of earthquake recurrence. However, this time-dependent series was interrupted by a cluster of earthquakes at ∼430 ka. The carbon isotope composition of calcite formed during this seismic cluster records rapid degassing of CO 2 , suggesting an interval of anomalous fluid source. In concert with U-Th dates recording decreased recurrence intervals, we infer seismicity during this interval records fault-valve behavior. These data provide insight into the long-term seismic behavior of the Loma Blanca fault and, by inference, other intraplate faults.

  3. Reading a 400,000-year record of earthquake frequency for an intraplate fault

    Science.gov (United States)

    Williams, Randolph T.; Goodwin, Laurel B.; Sharp, Warren D.; Mozley, Peter S.

    2017-05-01

    Our understanding of the frequency of large earthquakes at timescales longer than instrumental and historical records is based mostly on paleoseismic studies of fast-moving plate-boundary faults. Similar study of intraplate faults has been limited until now, because intraplate earthquake recurrence intervals are generally long (10s to 100s of thousands of years) relative to conventional paleoseismic records determined by trenching. Long-term variations in the earthquake recurrence intervals of intraplate faults therefore are poorly understood. Longer paleoseismic records for intraplate faults are required both to better quantify their earthquake recurrence intervals and to test competing models of earthquake frequency (e.g., time-dependent, time-independent, and clustered). We present the results of U-Th dating of calcite veins in the Loma Blanca normal fault zone, Rio Grande rift, New Mexico, United States, that constrain earthquake recurrence intervals over much of the past ˜550 ka—the longest direct record of seismic frequency documented for any fault to date. The 13 distinct seismic events delineated by this effort demonstrate that for >400 ka, the Loma Blanca fault produced periodic large earthquakes, consistent with a time-dependent model of earthquake recurrence. However, this time-dependent series was interrupted by a cluster of earthquakes at ˜430 ka. The carbon isotope composition of calcite formed during this seismic cluster records rapid degassing of CO2, suggesting an interval of anomalous fluid source. In concert with U-Th dates recording decreased recurrence intervals, we infer seismicity during this interval records fault-valve behavior. These data provide insight into the long-term seismic behavior of the Loma Blanca fault and, by inference, other intraplate faults.

  4. Injury, disability and quality of life after the 2009 earthquake in Padang, Indonesia: a prospective cohort study of adult survivors

    Directory of Open Access Journals (Sweden)

    Mondastri K. Sudaryo

    2012-05-01

    Full Text Available Background: On 30 September 2009, a 7.6 magnitude earthquake severely hit the coast of Padang city in West Sumatra, Indonesia leaving about 1,117 people dead and injuring another 3,515. Health consequences such as physical injury, co-morbidity, disability and quality of life over time are seldom reported among survivors after earthquakes. Objectives: To investigate the associations between injury, disability and quality of life amongst adult survivors in Padang city after the 2009 earthquake.Design/Methods: A prospective cohort study was conducted to compare adult injured (184 and adult non-injured (93 subjects over a 6-month period. Data on physical injury, co-morbidities, disability and quality of life were collected through interviews and measured quantitatively in three phases, i.e. at baseline, end of 3 and 6 months. Results: Disability scores were consistently and significantly higher among injured subjects compared to non-injured, even when adjusted for co-morbidities (i.e. acute symptoms and chronic diseases. The highest disability score amongst injured subjects was attributed to ‘feeling discomfort/pain’. Quality of life attribute (QLA scores, were significantly lower amongst injured people as compared to those non-injured even when adjusted for co-morbidities. The lowest QLA item score amongst the injured was ‘pain, depression and anxiety’. Significant and consistent negative correlations were found between disability and QLA scores in both the injured and non-injured groups. Conclusion: Physical injury is significantly correlated with both higher disability and lower quality of life, while disability has significant negative correlation with quality of life. The findings suggest that, through disability, injury may contribute to decreased quality of life. It is therefore recommended to promptly and adequately treat injuries after disasters to prevent any potential for disability and hence restore quality of life.

  5. A study of small explosions and earthquakes during 1961--1989 near the Semipalatinsk Test Site, Kazakhstan

    International Nuclear Information System (INIS)

    Khalturin, V.I.; Rautian, T.G.; Richards, P.G.; Columbia Univ., New York, NY

    1994-03-01

    Several Russian sources have stated that 343 underground nuclear explosions were conducted during 1961--1989 at the Semipalatinsk Test Site. However, only 282 of them appear to have been described, in the openly available technical literature, with well-determined coordinates; and only 272 have both good locations and magnitudes. The authors have used regional data from 52 stations to study 65 seismic sources initially thought to be in or near the Semipalatinsk region, additional to the 272 underground nuclear explosions with known locations and magnitudes. Of these 65 events, the authors believe 8 are not explosions on the test site, namely: two earthquakes close to the test site; three earthquakes or chemical explosions 100--300 km from the test site; and three events at greater distances from Semipalatinsk. Of the remaining 57 events: 10 were known to be underground nuclear explosions with known locations and the authors have supplied magnitudes where none were previously available; one was a chemical explosion at Degelen; they believe 21 were underground nuclear explosions; 13 were chemical explosions at Balapan; 8 were chemical explosions elsewhere on the test site; three were either nuclear or chemical explosions; and one was either a chemical explosion or a cavity collapse. The largest magnitude of their 44 possible underground nuclear explosions is around 5 (February 4, 1965, obscured at many teleseismic stations by a large Aleutian earthquake). Others lie in the magnitude range 3.5--4.5, and clearly most have sub kiloton yields. Their data set of small events is important for purposes of evaluating the detection capability of teleseismic arrays, and the detection and identification capability of regional stations

  6. Assessing Urban Streets Network Vulnerability against Earthquake Using GIS - Case Study: 6TH Zone of Tehran

    Science.gov (United States)

    Rastegar, A.

    2017-09-01

    Great earthquakes cause huge damages to human life. Street networks vulnerability makes the rescue operation to encounter serious difficulties especially at the first 72 hours after the incident. Today, physical expansion and high density of great cities, due to narrow access roads, large distance from medical care centers and location at areas with high seismic risk, will lead to a perilous and unpredictable situation in case of the earthquake. Zone # 6 of Tehran, with 229,980 population (3.6% of city population) and 20 km2 area (3.2% of city area), is one of the main municipal zones of Tehran (Iran center of statistics, 2006). Major land-uses, like ministries, embassies, universities, general hospitals and medical centers, big financial firms and so on, manifest the high importance of this region on local and national scale. In this paper, by employing indexes such as access to medical centers, street inclusion, building and population density, land-use, PGA and building quality, vulnerability degree of street networks in zone #6 against the earthquake is calculated through overlaying maps and data in combination with IHWP method and GIS. This article concludes that buildings alongside the streets with high population and building density, low building quality, far to rescue centers and high level of inclusion represent high rate of vulnerability, compared with other buildings. Also, by moving on from north to south of the zone, the vulnerability increases. Likewise, highways and streets with substantial width and low building and population density hold little values of vulnerability.

  7. Earthquake Early Warning Systems

    OpenAIRE

    Pei-Yang Lin

    2011-01-01

    Because of Taiwan’s unique geographical environment, earthquake disasters occur frequently in Taiwan. The Central Weather Bureau collated earthquake data from between 1901 and 2006 (Central Weather Bureau, 2007) and found that 97 earthquakes had occurred, of which, 52 resulted in casualties. The 921 Chichi Earthquake had the most profound impact. Because earthquakes have instant destructive power and current scientific technologies cannot provide precise early warnings in advance, earthquake ...

  8. Awareness and understanding of earthquake hazards at school

    Science.gov (United States)

    Saraò, Angela; Peruzza, Laura; Barnaba, Carla; Bragato, Pier Luigi

    2014-05-01

    Schools have a fundamental role in broadening the understanding of natural hazard and risks and in building the awareness in the community. Recent earthquakes in Italy and worldwide, have clearly demonstrated that the poor perception of seismic hazards diminishes the effectiveness of mitigation countermeasures. Since years the Seismology's department of OGS is involved in education projects and public activities to raise awareness about earthquakes. Working together with teachers we aim at developing age-appropriate curricula to improve the student's knowledge about earthquakes, seismic safety, and seismic risk reduction. Some examples of education activities we performed during the last years are here presented. We show our experience with the primary and intermediate schools where, through hands-on activities, we explain the earthquake phenomenon and its effects to kids, but we illustrate also some teaching interventions for high school students. During the past years we lectured classes, we led laboratory and field activities, and we organized summer stages for selected students. In the current year we are leading a project aimed at training high school students on seismic safety through a multidisciplinary approach that involves seismologists, engineers and experts of safety procedures. To combine the objective of dissemination of earthquake culture, also through the knowledge of the past seismicity, with that of a safety culture, we use innovative educational techniques and multimedia resources. Students and teachers, under the guidance of an expert seismologist, organize a combination of hands-on activities for understanding earthquakes in the lab through cheap tools and instrumentations At selected schools we provided the low cost seismometers of the QuakeCatcher network (http://qcn.stanford.edu) for recording earthquakes, and we trained teachers to use such instruments in the lab and to analyze recorded data. Within the same project we are going to train

  9. Fault failure with moderate earthquakes

    Science.gov (United States)

    Johnston, M. J. S.; Linde, A. T.; Gladwin, M. T.; Borcherdt, R. D.

    1987-12-01

    High resolution strain and tilt recordings were made in the near-field of, and prior to, the May 1983 Coalinga earthquake ( ML = 6.7, Δ = 51 km), the August 4, 1985, Kettleman Hills earthquake ( ML = 5.5, Δ = 34 km), the April 1984 Morgan Hill earthquake ( ML = 6.1, Δ = 55 km), the November 1984 Round Valley earthquake ( ML = 5.8, Δ = 54 km), the January 14, 1978, Izu, Japan earthquake ( ML = 7.0, Δ = 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.

  10. The October 1992 Parkfield, California, earthquake prediction

    Science.gov (United States)

    Langbein, J.

    1992-01-01

    A magnitude 4.7 earthquake occurred near Parkfield, California, on October 20, 992, at 05:28 UTC (October 19 at 10:28 p.m. local or Pacific Daylight Time).This moderate shock, interpreted as the potential foreshock of a damaging earthquake on the San Andreas fault, triggered long-standing federal, state and local government plans to issue a public warning of an imminent magnitude 6 earthquake near Parkfield. Although the predicted earthquake did not take place, sophisticated suites of instruments deployed as part of the Parkfield Earthquake Prediction Experiment recorded valuable data associated with an unusual series of events. this article describes the geological aspects of these events, which occurred near Parkfield in October 1992. The accompnaying article, an edited version of a press conference b Richard Andrews, the Director of the California Office of Emergency Service (OES), describes governmental response to the prediction.   

  11. Responses of a tall building with U.S. code-type instrumentation in Tokyo, Japan, to events before, during and after the Tohoku earthquake of 11 March 2011

    Science.gov (United States)

    Çelebi, Mehmet; Kashima, Toshihide; Ghahari, S. Farid; Abazarsa, Fariba; Taciroglu, Ertugrul

    2016-01-01

    The 11 March 2011 M 9.0 Tohoku earthquake generated long-duration shaking that propagated hundreds of kilometers from the epicenter and affected tall buildings in urban areas several hundred kilometers from the epicenter of the main shock. Recorded responses show that tall buildings were affected by long-period motions. This study presents the behavior and performance of a 37-story building in the Tsukuda area of Tokyo, Japan, as inferred from modal analyses of records retrieved for a time interval covering a few days before, during, and for several months after the main shock. The U.S. “code-type” array comprises three triaxial accelerometers deployed at three levels in the superstructure. Such a sparse array in a tall structure limits a reliable assessment, because its performance must be based on only the average drift ratios. Based on the inferred values of this parameter, the subject building was not structurally damaged.

  12. Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587-1996)

    Science.gov (United States)

    Beauval, Céline; Yepes, Hugo; Bakun, William H.; Egred, José; Alvarado, Alexandra; Singaucho, Juan-Carlos

    2010-06-01

    The whole territory of Ecuador is exposed to seismic hazard. Great earthquakes can occur in the subduction zone (e.g. Esmeraldas, 1906, Mw 8.8), whereas lower magnitude but shallower and potentially more destructive earthquakes can occur in the highlands. This study focuses on the historical crustal earthquakes of the Andean Cordillera. Several large cities are located in the Interandean Valley, among them Quito, the capital (~2.5 millions inhabitants). A total population of ~6 millions inhabitants currently live in the highlands, raising the seismic risk. At present, precise instrumental data for the Ecuadorian territory is not available for periods earlier than 1990 (beginning date of the revised instrumental Ecuadorian seismic catalogue); therefore historical data are of utmost importance for assessing seismic hazard. In this study, the Bakun & Wentworth method is applied in order to determine magnitudes, locations, and associated uncertainties for historical earthquakes of the Sierra over the period 1587-1976. An intensity-magnitude equation is derived from the four most reliable instrumental earthquakes (Mw between 5.3 and 7.1). Intensity data available per historical earthquake vary between 10 (Quito, 1587, Intensity >=VI) and 117 (Riobamba, 1797, Intensity >=III). The bootstrap resampling technique is coupled to the B&W method for deriving geographical confidence contours for the intensity centre depending on the data set of each earthquake, as well as confidence intervals for the magnitude. The extension of the area delineating the intensity centre location at the 67 per cent confidence level (+/-1σ) depends on the amount of intensity data, on their internal coherence, on the number of intensity degrees available, and on their spatial distribution. Special attention is dedicated to the few earthquakes described by intensities reaching IX, X and XI degrees. Twenty-five events are studied, and nineteen new epicentral locations are obtained, yielding

  13. Locations and magnitudes of historical earthquakes in the Sierra of Ecuador (1587–1996)

    Science.gov (United States)

    Beauval, Celine; Yepes, Hugo; Bakun, William H.; Egred, Jose; Alvarado, Alexandra; Singaucho, Juan-Carlos

    2010-01-01

    The whole territory of Ecuador is exposed to seismic hazard. Great earthquakes can occur in the subduction zone (e.g. Esmeraldas, 1906, Mw8.8), whereas lower magnitude but shallower and potentially more destructive earthquakes can occur in the highlands. This study focuses on the historical crustal earthquakes of the Andean Cordillera. Several large cities are located in the Interandean Valley, among them Quito, the capital (∼2.5 millions inhabitants). A total population of ∼6 millions inhabitants currently live in the highlands, raising the seismic risk. At present, precise instrumental data for the Ecuadorian territory is not available for periods earlier than 1990 (beginning date of the revised instrumental Ecuadorian seismic catalogue); therefore historical data are of utmost importance for assessing seismic hazard. In this study, the Bakun & Wentworth method is applied in order to determine magnitudes, locations, and associated uncertainties for historical earthquakes of the Sierra over the period 1587–1976. An intensity-magnitude equation is derived from the four most reliable instrumental earthquakes (Mwbetween 5.3 and 7.1). Intensity data available per historical earthquake vary between 10 (Quito, 1587, Intensity ≥VI) and 117 (Riobamba, 1797, Intensity ≥III). The bootstrap resampling technique is coupled to the B&W method for deriving geographical confidence contours for the intensity centre depending on the data set of each earthquake, as well as confidence intervals for the magnitude. The extension of the area delineating the intensity centre location at the 67 per cent confidence level (±1σ) depends on the amount of intensity data, on their internal coherence, on the number of intensity degrees available, and on their spatial distribution. Special attention is dedicated to the few earthquakes described by intensities reaching IX, X and XI degrees. Twenty-five events are studied, and nineteen new epicentral locations are obtained, yielding

  14. Improving automatic earthquake locations in subduction zones: a case study for GEOFON catalog of Tonga-Fiji region

    Science.gov (United States)

    Nooshiri, Nima; Heimann, Sebastian; Saul, Joachim; Tilmann, Frederik; Dahm, Torsten

    2015-04-01

    Automatic earthquake locations are sometimes associated with very large residuals up to 10 s even for clear arrivals, especially for regional stations in subduction zones because of their strongly heterogeneous velocity structure associated. Although these residuals are most likely not related to measurement errors but unmodelled velocity heterogeneity, these stations are usually removed from or down-weighted in the location procedure. While this is possible for large events, it may not be useful if the earthquake is weak. In this case, implementation of travel-time station corrections may significantly improve the automatic locations. Here, the shrinking box source-specific station term method (SSST) [Lin and Shearer, 2005] has been applied to improve relative location accuracy of 1678 events that occurred in the Tonga subduction zone between 2010 and mid-2014. Picks were obtained from the GEOFON earthquake bulletin for all available station networks. We calculated a set of timing corrections for each station which vary as a function of source position. A separate time correction was computed for each source-receiver path at the given station by smoothing the residual field over nearby events. We begin with a very large smoothing radius essentially encompassing the whole event set and iterate by progressively shrinking the smoothing radius. In this way, we attempted to correct for the systematic errors, that are introduced into the locations by the inaccuracies in the assumed velocity structure, without solving for a new velocity model itself. One of the advantages of the SSST technique is that the event location part of the calculation is separate from the station term calculation and can be performed using any single event location method. In this study, we applied a non-linear, probabilistic, global-search earthquake location method using the software package NonLinLoc [Lomax et al., 2000]. The non-linear location algorithm implemented in NonLinLoc is less

  15. Physics of Earthquake Rupture Propagation

    Science.gov (United States)

    Xu, Shiqing; Fukuyama, Eiichi; Sagy, Amir; Doan, Mai-Linh

    2018-05-01

    A comprehensive understanding of earthquake rupture propagation requires the study of not only the sudden release of elastic strain energy during co-seismic slip, but also of other processes that operate at a variety of spatiotemporal scales. For example, the accumulation of the elastic strain energy usually takes decades to hundreds of years, and rupture propagation and termination modify the bulk properties of the surrounding medium that can influence the behavior of future earthquakes. To share recent findings in the multiscale investigation of earthquake rupture propagation, we held a session entitled "Physics of Earthquake Rupture Propagation" during the 2016 American Geophysical Union (AGU) Fall Meeting in San Francisco. The session included 46 poster and 32 oral presentations, reporting observations of natural earthquakes, numerical and experimental simulations of earthquake ruptures, and studies of earthquake fault friction. These presentations and discussions during and after the session suggested a need to document more formally the research findings, particularly new observations and views different from conventional ones, complexities in fault zone properties and loading conditions, the diversity of fault slip modes and their interactions, the evaluation of observational and model uncertainties, and comparison between empirical and physics-based models. Therefore, we organize this Special Issue (SI) of Tectonophysics under the same title as our AGU session, hoping to inspire future investigations. Eighteen articles (marked with "this issue") are included in this SI and grouped into the following six categories.

  16. Safety Assessment of Two Hybrid Instrumentation Techniques in a Dental Student Endodontic Clinic: A Retrospective Study.

    Science.gov (United States)

    Coelho, Marcelo Santos; Card, Steven John; Tawil, Peter Zahi

    2017-03-01

    The aim of this study was to retrospectively assess the safety potential of a hybrid technique combining nickel-titanium (NiTi) reciprocating and rotary instruments by third- and fourth-year dental students in the predoctoral endodontics clinic at one U.S. dental school. For the study, 3,194 root canal treatments performed by 317 dental students from 2012 through 2015 were evaluated for incidence of ledge creation and instrument separation. The hybrid reciprocating and rotary technique (RRT) consisted of a glide path creation with stainless steel hand files up to size 15/02, a crown down preparation with a NiTi reciprocating instrument, and an apical preparation with NiTi rotary instruments. The control was a traditional rotary and hand technique (RHT) that consisted of the same glide path procedure followed by a crown down preparation with NiTi rotary instruments and an apical preparation with NiTi hand instruments. The results showed that the RHT technique presented a rate of ledge creation of 1.4% per root and the RRT technique was 0.5% per root (protary technique for root canal instrumentation by these dental students provided good safety. This hybrid technique offered a low rate of ledge creation along with no NiTi instrument separation.

  17. The MSA: An Instrument for Measuring Motivation to Study Abroad

    Science.gov (United States)

    Anderson, Philip H.; Lawton, Leigh

    2015-01-01

    While there is a growing body of research on study abroad programs, as Li, Olson, and Frieze (2013) observed, "Research on study abroad has primarily focused on the effects or outcomes of study abroad participation on the students involved in these programs…Very limited attention has been devoted to studying factors affecting students'…

  18. Båth's law and its relation to the tectonic environment: A case study for earthquakes in Mexico

    Science.gov (United States)

    Rodríguez-Pérez, Q.; Zúñiga, F. R.

    2016-09-01

    We studied 66 mainshocks and their largest aftershocks in the Mexican subduction zone and in the Gulf of California with magnitudes in the range of 5.2 worldwide studies supporting the observation of mechanism dependence of radiated seismic energy. The statistical tests indicate that the only significant difference is for shallow thrust and strike-slip events for these parameters. The statistical comparison of stress drop of shallow thrust versus that of inslab events shows a strongly significant difference with a confidence better than 99%. The comparison of stress drop of shallow thrust events with that of strike-slip events, also indicates a strongly significant difference. We see no dependence of stress drop with magnitude, which is strong evidence of earthquake self-similarity. We do not observe a systematic depth dependence of stress drop. The results also reveal differences in the earthquake rupture among the events. The magnitude difference between the mainshock and the largest aftershock for inslab events is larger than interplate and strike-slip events suggesting focal mechanism dependence of Båth's law. For the case of this parameter, only that for inslab and strike-slip events present a significant difference with 95% confidence.

  19. GEOS seismograms for aftershocks of the earthquakes of December 7, 1988, near Spitak, Armenia SSR, during the time period 30 December 1988 14:00 through 2 January 1989 (UTC): Chapter D in Results and data from seismologic and geologic studies following earthquakes of December 7, 1988, near Spitak, Armenia SSR (Open-File Report 89-163)

    Science.gov (United States)

    Borcherdt, R.D.; Glassmoyer, Gary; Cranswick, Edward

    1989-01-01

    The earthquakes of December 7, 1988, near Spitak, Armenia SSR, serve as another grim reminder of the serious hazard that earthquakes pose throughout the world. We extend our heartfelt sympathies to the families of the earthquake victims and intend that our cooperative scientific endeavours will help reduce losses in future earthquakes. Only through a better understanding of earthquake hazards can earthquake losses be reduced for all peoples in seismically active regions of the world.The tragic consequences of these earthquakes remind scientists and public officials alike of their urgent responsibilities to understand and mitigate the effects of earthquakes. On behalf of the U.S. Geological Survey, I would like to express appreciation to our Soviet colleagues for their kind invitation to participate in joint scientific and engineering studies. Without their cooperation and generous assistance, the conduct of these studies would not have been possible.This report provides seismologic and geologic data collected during the time period December 21, 1988, through February 2, 1989. These data are presented in their entirety to expedite analysis of the data set for inferences regarding hazard mitigation actions, applicable not only in Armenia but other regions of the world exposed to high seismic risk

  20. More major earthquakes at the Nepal Himalaya? - Study on Coulomb stress perspective

    Science.gov (United States)

    Som, S. K.; Sarkar, Subhrasuchi; Dasgupta, Soumitra

    2018-07-01

    On April 2015 a major earthquake of 7.9 Mw occurred in the Nepal Himalaya, followed by 553 earthquakes of local magnitude greater than 4.0 within the first 43 days including another major event of 7.3 Mw. We resolve the static coulomb failure stress (CFS) change onto the finite fault models of 7.9 Mw after Elliott et al. (2016) and Galezka et al. (2015) and its effect on associated receiver faults. Correlation of aftershocks with the enhanced CFS condition shows that the Elliott et al. (2016) model explains 60.4% and the Galezka et al. (2015) model explains about 47.7% of the aftershocks in high stress regions. Aftershocks were poorly spatially correlated with the enhanced CFS condition after the 7.9 Mw main shock and can be explained by correlation with release of seismic energy from the associated secondarily stressed prominent thrust planes and transverse faults. Stress resolved on the associated receiver faults show increased stress on both transverse and thrust fault systems with the potential of triggering significant aftershocks or subsequent main shocks.

  1. A longitudinal study of posttraumatic stress disorder symptoms and its relationship with coping skill and locus of control in adolescents after an earthquake in China.

    Science.gov (United States)

    Zhang, Weiqing; Liu, Hui; Jiang, Xiaolian; Wu, Dongmei; Tian, Yali

    2014-01-01

    Post-traumatic stress disorder is a common psychological maladaptation among adolescents after undergoing an earthquake. Knowledge about the prevalence and maintenance of post-traumatic stress disorder symptoms and the changes of its predictors over time can help medical providers assist adolescent survivors with mitigating long-term impacts. This study examined the changes in posttraumatic stress disorder symptoms and its relationship with coping skill and locus of control among adolescent earthquake survivors in China. The study used an observational longitudinal design. A total of 1420 adolescents were evaluated twice after the earthquake by using the Post-traumatic stress disorder Checklist-Civilian Version, The Internality, Powerful others and Chance scale and the Coping Styles Scale. The results indicated that the mean scores of posttraumatic stress disorder symptoms were decreased significantly and the positive rates of posttraumatic stress disorder symptoms also declined remarkably at 17 months compared to the 3 months post-earthquake. Internality locus of control and problem solving coping skill were effective resilient factors for the development and maintenance of posttraumatic stress disorder symptoms, while chance locus of control was a powerful risk factor of posttraumatic stress disorder symptoms as well as being female, being injured and property loss. Continuous screening is recommended to identify adolescent earthquake survivors with posttraumatic stress disorder symptoms. More attention should be paid to adolescent survivors who are prone to adopt passive coping strategies responding to trauma events and who own external causal attribution.

  2. Real Time Earthquake Information System in Japan

    Science.gov (United States)

    Doi, K.; Kato, T.

    2003-12-01

    An early earthquake notification system in Japan had been developed by the Japan Meteorological Agency (JMA) as a governmental organization responsible for issuing earthquake information and tsunami forecasts. The system was primarily developed for prompt provision of a tsunami forecast to the public with locating an earthquake and estimating its magnitude as quickly as possible. Years after, a system for a prompt provision of seismic intensity information as indices of degrees of disasters caused by strong ground motion was also developed so that concerned governmental organizations can decide whether it was necessary for them to launch emergency response or not. At present, JMA issues the following kinds of information successively when a large earthquake occurs. 1) Prompt report of occurrence of a large earthquake and major seismic intensities caused by the earthquake in about two minutes after the earthquake occurrence. 2) Tsunami forecast in around three minutes. 3) Information on expected arrival times and maximum heights of tsunami waves in around five minutes. 4) Information on a hypocenter and a magnitude of the earthquake, the seismic intensity at each observation station, the times of high tides in addition to the expected tsunami arrival times in 5-7 minutes. To issue information above, JMA has established; - An advanced nationwide seismic network with about 180 stations for seismic wave observation and about 3,400 stations for instrumental seismic intensity observation including about 2,800 seismic intensity stations maintained by local governments, - Data telemetry networks via landlines and partly via a satellite communication link, - Real-time data processing techniques, for example, the automatic calculation of earthquake location and magnitude, the database driven method for quantitative tsunami estimation, and - Dissemination networks, via computer-to-computer communications and facsimile through dedicated telephone lines. JMA operationally

  3. Impaired psychological recovery in the elderly after the Niigata-Chuetsu Earthquake in Japan:a population-based study

    Directory of Open Access Journals (Sweden)

    Someya Toshiyuki

    2006-09-01

    Full Text Available Abstract Background An earthquake measuring 6.8 on the Richter scale struck the Niigata-Chuetsu region of Japan at 5.56 P.M. on the 23rd of October, 2004. The earthquake was followed by sustained occurrence of numerous aftershocks, which delayed reconstruction of community lifelines. Even one year after the earthquake, 9,160 people were living in temporary housing. Such a devastating earthquake and life after the earthquake in an unfamiliar environment should cause psychological distress, especially among the elderly. Methods Psychological distress was measured using the 12-item General Health Questionnaire (GHQ-12 in 2,083 subjects (69% response rate who were living in transient housing five months after the earthquake. GHQ-12 was scored using the original method, Likert scoring and corrected method. The subjects were asked to assess their psychological status before the earthquake, their psychological status at the most stressful time after the earthquake and their psychological status at five months after the earthquake. Exploratory and confirmatory factor analysis was used to reveal the factor structure of GHQ12. Multiple regression analysis was performed to analyze the relationship between various background factors and GHQ-12 score and its subscale. Results GHQ-12 scores were significantly elevated at the most stressful time and they were significantly high even at five months after the earthquake. Factor analysis revealed that a model consisting of two factors (social dysfunction and dysphoria using corrected GHQ scoring showed a high level of goodness-of-fit. Multiple regression analysis revealed that age of subjects affected GHQ-12 scores. GHQ-12 score as well as its factor 'social dysfunction' scale were increased with increasing age of subjects at five months after the earthquake. Conclusion Impaired psychological recovery was observed even at five months after the Niigata-Chuetsu Earthquake in the elderly. The elderly were more

  4. Can mine tremors be predicted? Observational studies of earthquake nucleation, triggering and rupture in South African mines

    CSIR Research Space (South Africa)

    Durrheim, RJ

    2012-05-01

    Full Text Available Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant risk to inhabitants of stable continental regions where destructive earthquakes are rare... of experiments that seek to identify reliable precursors of damaging seismic events. 1. Introduction Earthquakes, and the tsunamis and landslides they trigger, pose a serious risk to people living close to plate boundaries, and a lesser but still significant...

  5. Experimental Study on a Self-Centering Earthquake-Resistant Masonry Pier with a Structural Concrete Column

    Directory of Open Access Journals (Sweden)

    Lijun Niu

    2017-01-01

    Full Text Available This paper proposes a slotting construction strategy to avoid shear behavior of multistory masonry buildings. The aspect ratio of masonry piers increases via slotting between spandrels and piers, so that the limit state of piers under an earthquake may be altered from shear to rocking. Rocking piers with a structural concrete column (SCC form a self-centering earthquake-resistant system. The in-plane lateral rocking behavior of masonry piers subjected to an axial force is predicted, and an experimental study is conducted on two full-scale masonry piers with an SCC, which consist of a slotting pier and an original pier. Meanwhile, a comparison of the rocking modes of masonry piers with an SCC and without an SCC was conducted in the paper. Experimental verification indicates that the slotting strategy achieves a change of failure modes from shear to rocking, and this resistant system with an SCC incorporates the self-centering and high energy dissipation properties. For the slotting pier, a lateral story drift ratio of 2.5% and a high displacement ductility of approximately 9.7 are obtained in the test, although the lateral strength decreased by 22.3% after slotting. The predicted lateral strength of the rocking pier with an SCC has a margin of error of 5.3%.

  6. Ionospheric phenomena before strong earthquakes

    Directory of Open Access Journals (Sweden)

    A. S. Silina

    2001-01-01

    Full Text Available A statistical analysis of several ionospheric parameters before earthquakes with magnitude M > 5.5 located less than 500 km from an ionospheric vertical sounding station is performed. Ionospheric effects preceding "deep" (depth h > 33 km and "crust" (h 33 km earthquakes were analysed separately. Data of nighttime measurements of the critical frequencies foF2 and foEs, the frequency fbEs and Es-spread at the middle latitude station Dushanbe were used. The frequencies foF2 and fbEs are proportional to the square root of the ionization density at heights of 300 km and 100 km, respectively. It is shown that two days before the earthquakes the values of foF2 averaged over the morning hours (00:00 LT–06:00 LT and of fbEs averaged over the nighttime hours (18:00 LT–06:00 LT decrease; the effect is stronger for the "deep" earthquakes. Analysing the coefficient of semitransparency which characterizes the degree of small-scale turbulence, it was shown that this value increases 1–4 days before "crust" earthquakes, and it does not change before "deep" earthquakes. Studying Es-spread which manifests itself as diffuse Es track on ionograms and characterizes the degree of large-scale turbulence, it was found that the number of Es-spread observations increases 1–3 days before the earthquakes; for "deep" earthquakes the effect is more intensive. Thus it may be concluded that different mechanisms of energy transfer from the region of earthquake preparation to the ionosphere occur for "deep" and "crust" events.

  7. Structure and tectonics of the Main Himalayan Thrust and associated faults from recent earthquake and seismic imaging studies using the NAMASTE array

    Science.gov (United States)

    Karplus, M. S.; Pant, M.; Velasco, A. A.; Nabelek, J.; Kuna, V. M.; Sapkota, S. N.; Ghosh, A.; Mendoza, M.; Adhikari, L. B.; Klemperer, S. L.

    2017-12-01

    The India-Eurasia collision zone presents a significant earthquake hazard, as demonstrated by the recent, devastating April 25, 2015 M=7.8 Gorkha earthquake and the following May 12, 2015 M=7.3 earthquake. Important questions remain, including distinguishing possible geometries of the Main Himalayan Thrust (MHT), the role of other regional faults, the crustal composition and role of fluids in faulting, and the details of the rupture process, including structural causes and locations of rupture segmentation both along-strike and down-dip. These recent earthquakes and their aftershocks provide a unique opportunity to learn more about this collision zone. In June 2015, funded by NSF, we deployed the Nepal Array Measuring Aftershock Seismicity Trailing Earthquake (NAMASTE) array of 46 seismic stations distributed across eastern and central Nepal, spanning the region with most of the aftershocks. This array remained in place for 11 months from June 2015 to May 2016. We combine new results from this aftershock network in Nepal with previous geophysical and geological studies across the Himalaya to derive a new understanding of the tectonics of the Himalaya and southern Tibet in Nepal and surrounding countries. We focus on structure and composition of the Main Himalayan Thrust and compare this continent-continent subduction megathrust with megathrusts in other subduction zones.

  8. Challenges for implementing Earthquake Early Warning: A Case Study in Nicaragua

    Science.gov (United States)

    Massin, F.; Clinton, J. F.; Boese, M.; Cauzzi, C.; Strauch, W.

    2017-12-01

    Earthquake early warning (EEW) systems aim at providing fast and accurate estimates of event parameters or local ground shaking over wide ranges of source dimensions and epicentral distances. The Swiss Seismological Service (SED) has integrated EEW solutions into the SeisComP3 (SC3) professional earthquake monitoring software. VS(SC3) provides fast magnitude estimates for network-based point-sources using conventional triggering and phases association techniques, while FinDer(SC3) matches the evolving patterns of ground motion to track on-going rupture extent, and can provide accurate ground motion predictions for finite fault ruptures. SC3 is widely used, including in Central America, and at INETER in Nicaragua. In 2016, SED and INETER started a joint project to assess the feasibility of EEW in Nicaragua and Central America and to set up a prototype EEW system. We test VS(SC3) and FinDer(SC3) softwares at INETER since 2016. Excellent relations between regional seismic networks mean broadband and strong motion seismic data are exchanged across Central America in real time, which means the network is sufficient to warrant investigation into its potential for EEW. We report on the successes and challenges of operating an EEW system where seismicity is high, but infrastructure is fragile and the design and operation of a seismic network is challenging (in Nicaragua, on average 50% of all stations do not work effectively for EEW). The current best EEW delays for on-shore earthquakes in Nicaragua is in the order of 20s and 40s offshore. However, the current network should be able to provide EEW in 10 to 15s on-shore and 20 to 25s off-shore which correspond to potential EEW intensities over or equal to VII. We compare the performances of EEW in Nicaragua with an ideal setting, featuring optimized data availability. We evaluate improvements strategies of the Nicaraguan and the Joint Central American Seismic Networks for EEW. And we discuss how to combine real-time EEW

  9. How Do Regional Stress Changes Following Megathrust Events Affect Active Retroarc Tectonics? A Case Study of the 27 February 2010 Mw 6.1 Salta Earthquake

    Science.gov (United States)

    McFarland, P. K.; Bennett, R. A.

    2017-12-01

    The 27 February 2010 M­­w 6.1 Salta earthquake occurred in the active retroarc fold-thrust belt of northwest Argentina approximately 9 hours after and 1500 km away from the Mw 8.8 Maule earthquake that occurred off the coast of central Chile. It has been proposed that the Salta earthquake occurred on a fault that was already at or near failure at the time of the Maule event, and the Maule earthquake simply advanced the seismic cycle of the fault. In this study, we examine a transient signal in the east component of the position time series for the continuously operating GPS (cGPS) station UNSA, which lies approximately 32 km northeast of the Salta earthquake epicenter. The transient signal is observed in the roughly 2.3 years prior to the Salta earthquake. It begins immediately following the 11 November 2007 Mw 7.7 Tocopilla megathrust event that occurred about 550 km due west of Salta on the Nazca-South America subduction interface and terminates abruptly after the Salta earthquake. We use the published relocated main shock and aftershock hypocenters determined using data from a local seismic network (INPRES) along with the published main shock focal mechanism to demonstrate that the Salta earthquake likely occurred on the Golgota Fault, a N-S striking and steeply-east-dipping reverse fault. Further, we use elastic dislocation modeling to show that rupture on the Golgota Fault is consistent with the co-seismic offsets observed at the surrounding cGPS stations. We propose that the transient signal observed at station UNSA may be due to initiation or acceleration of interseismic strain accumulation on the Golgota Fault at mid-crustal depths following a change in the regional stress field associated with the Tocopilla megathrust earthquake. Finally, we use published rupture models for both the Tocopilla and Maule events to demonstrate that the regional static Coulomb stress change following each of these megathrusts is consistent with our proposed model.

  10. Validation of physical activity instruments: Black Women's Health Study.

    Science.gov (United States)

    Carter-Nolan, Pamela L; Adams-Campbell, Lucile L; Makambi, Kepher; Lewis, Shantell; Palmer, Julie R; Rosenberg, Lynn

    2006-01-01

    Few studies have reported on the validity of physical activity measures in African Americans. The present study was designed to determine the validity of a self-administered physical activity questionnaire (PAQ) that was used in a large prospective study of African American women in the United States against an accelerometer (actigraph), an objective assessment of movement, and a seven-day activity diary. The study was conducted among 101 women enrolled in the Black Women's Health Study (BWHS) cohort who resided in the Washington, DC, metropolitan area, representing 11.2% (101/900) of this sample. Physical activity levels were obtained from the parent BWHS PAQ (eg, 1997 and 1999) and repeated in the present study. This information entailed hours per week of participation in walking for exercise, hours per week of moderate activity (eg, housework, gardening, and bowling), and hours per week of strenuous activity (eg, basketball, swimming, running, and aerobics) during the previous year. The participants were required to wear actigraphs for seven days and then record their physical activities in their diaries (seven-day physical activity diary) during this time. The diaries were used to record the amount and pattern of daily energy expenditure. Significant positive correlations were seen between the BWHS PAQ and the actigraph for total activity, r=.28; walking, r=.26; and vigorous activity, r=.40, PPAQ also demonstrated significant correlations for total (r=0.42, PPAQ is a useful measure of physical activity in the BWHS cohort and thus has utility in prospective epidemiologic research.

  11. Study Of The Rupture Process Of The 2015 Mw7.8 Izu-Bonin Earthquake And Its Implication To Deep-Focus Earthquake Genesis.

    Science.gov (United States)

    Jian, P. R.; Hung, S. H.; Meng, L.

    2015-12-01

    On May 30, 2015, a major Mw7.8 great deep earthquake occurred at the base of the mantle transition zone (MTZ), approximately 680 km deep within the Pacific Plate which subducts westward under the Philippine Sea Plate along the Izu-Bonin trench. A global P wave tomographic image indicates that a tabular high-velocity structure delineated by ~1% faster than the ambient mantle plunges nearly vertical to a depth at most 600 km and afterword flattens and stagnates within the MTZ. Almost all the deep earthquakes in this region are clustered inside this fast anomaly corresponding to the cold core of the subducting slab. Those occurring at depth between 400~500 km close to the hinge of the bending slab show down-dip compressional focal mechanisms and reflect episodic release of compressive strain accumulated in the slab. The 2015 deep event, however, separated from the others, occurred uniquely near the base of the lithosphere with a down-dip extension mechanism, consistent with the notion that the outer portion of the folded slab experiences extensional bending stress. Here we perform a 3D MUSIC back-projection (BP) rupture imaging for this isolated deep event using P and pP waveforms individually from the European, North American and Australian array data. By integrating P- and pP- BP images in frequencies of 0.1-1 Hz obtained from three array observations with different azimuth, we first ascertain the most possible fault plan is the SW-dipping subhorizontal one. Then, from back-projecting higher frequency waveforms at 1-1.5 Hz onto the obtained fault plane, we find the rupture initially propagates slowly along the strike (SW-direction), and makes a turn to the NNW-direction at ~12s after the onset of rupture. The MUSIC psudospectrum over totally 20s rupture duration reveals that most seismic energy radiation takes place at the initial 8s of the first rupture along the strike, 10-15 km long region, while the along-updip second rupture lasting for 6-10s has a rupture

  12. Experimental study of laminated rubber bearings for earthquake isolation of buildings, 2

    International Nuclear Information System (INIS)

    Fujita, Takafumi; Fujita, Satoshi; Suzuki, Shigenobu; Yoshizawa, Toshikazu.

    1987-01-01

    Rubber bearings of 980 kN rated load were tested to investigate the characteristics of restoring forces of full scale bearings for earthquake isolation of buildings. These bearings comprising 27 natural rubber sheets of 6 mm thickness and 600 mm diameter bonded to steel plates were designed to provide a 100000 kg rated mass with a horizontal natural frequency of 0.51 Hz and a vertical one of 21 Hz and to accept a horizontal displacement larger than 300 mm. The static tests were carried out with satisfactory results. It was confirmed that the performance of the bearing met the specifications well. Furthermore, the vertical load distributions across the top plane of the bearing under various horizontal displacements were measured, and showed that they were always concentrated in the overlapping area of the top and bottom planes. This verified that the rubber bearing substantially supported the vertical load by the overlapping area. (author)

  13. Study of seismological evasion. Part III. Evaluation of evasion possibilities using codas of large earthquakes

    International Nuclear Information System (INIS)

    Evernden, J.F.

    1976-01-01

    The seismological aspects of various proposed means of obscuring or hiding the seismic signatures of explosions from a surveillance network are discussed. These so-called evasion schemes are discussed from the points of view of both the evader and the monitor. The analysis will be conducted in terms of the USSR solely because that country is so vast and the geological/geophysical complexities of the country are so great that the complete spectrum of hypothesized evasion schemes requires discussion. Techniques appropriate for use when the seismic noise problem is interference due to codas of P and surface waves from earthquakes are described, and the capabilities of several seismological networks to restrain use of such codas for effective evasion are analyzed

  14. Study on Earthquake Response of High Voltage Electrical Equipment Coupling System with Flexible Busbar

    Science.gov (United States)

    Liu, Chuncheng; Qu, Da; Wang, Chongyang; Lv, Chunlei; Li, Guoqiang

    2017-12-01

    With the rapid development of technology and society, all walks of life in China are becoming more and more dependent on power systems. When earthquake occurs, the electrical equipment of substation is prone to damage because of its own structural features, top-heavy, and brittleness of main body. At the same time, due to the complex coupling of the soft electrical connection of substation electrical equipment, the negative impact can not be estimated. In this paper, the finite element model of the coupling system of the single unit of high voltage electrical equipment with the connecting soft bus is established and the seismic response is analysed. The results showed that there is a significant difference between the simple analysis for the seismic response of electrical equipment monomer and the analytical results of electrical equipment systems, and the impact on different electrical equipment is different. It lays a foundation for the future development of seismic performance analysis of extra high voltage electrical equipment.

  15. Finite Element Study on Continuous Rotating versus Reciprocating Nickel-Titanium Instruments.

    Science.gov (United States)

    El-Anwar, Mohamed I; Yousief, Salah A; Kataia, Engy M; El-Wahab, Tarek M Abd

    2016-01-01

    In the present study, GTX and ProTaper as continuous rotating endodontic files were numerically compared with WaveOne reciprocating file using finite element analysis, aiming at having a low cost, accurate/trustworthy comparison as well as finding out the effect of instrument design and manufacturing material on its lifespan. Two 3D finite element models were especially prepared for this comparison. Commercial engineering CAD/CAM package was used to model full detailed flute geometries of the instruments. Multi-linear materials were defined in analysis by using real strain-stress data of NiTi and M-Wire. Non-linear static analysis was performed to simulate the instrument inside root canal at a 45° angle in the apical portion and subjected to 0.3 N.cm torsion. The three simulations in this study showed that M-Wire is slightly more resistant to failure than conventional NiTi. On the other hand, both materials are fairly similar in case of severe locking conditions. For the same instrument geometry, M-Wire instruments may have longer lifespan than the conventional NiTi ones. In case of severe locking conditions both materials will fail similarly. Larger cross sectional area (function of instrument taper) resisted better to failure than the smaller ones, while the cross sectional shape and its cutting angles could affect instrument cutting efficiency.

  16. In vitro comparative study of manual and mechanical rotary instrumentation of root canals using computed tomography.

    Science.gov (United States)

    Limongi, Orlando; de Albuquerque, Diana Santana; Baratto Filho, Flares; Vanni, José Roberto; de Oliveira, Elias P Motcy; Barletta, Fernando Branco

    2007-01-01

    This in vitro study compared, using computed tomography (CT), the amount of dentin removed from root canal walls by manual and mechanical rotary instrumentation techniques. Forty mandibular incisors with dental crown and a single canal were selected. The teeth were randomly assigned to two groups, according to the technique used for root canal preparation: Group I - manual instrumentation with stainless steel files; Group II - mechanical instrumentation with RaCe rotary nickel-titanium instruments. In each tooth, root dentin thickness of the buccal, lingual, mesial and distal surfaces in the apical, middle and cervical thirds of the canal was measured (in mm) using a multislice CT scanner (Siemens Emotion, Duo). Data were stored in the SPSS v. 11.5 and SigmaPlot 2001 v. 7.101 softwares. After crown opening, working length was determined, root canals were instrumented and new CT scans were taken for assessment of root dentin thickness. Pre- and post-instrumentation data were compared and analyzed statistically by ANOVA and Tukey's post-hoc test for significant differences (p=0.05). Based on the findings of this study, it may be concluded that regarding dentin removal from root canal walls during instrumentation, neither of the techniques can be considered more effective than the other.

  17. Instruments to study sleep disorders in climacteric women

    Directory of Open Access Journals (Sweden)

    Álvaro Monterrosa-Castro

    2016-07-01

    Full Text Available To identify the scales to assess sleep disorders applied to women with climacteric stage. Bibliographical research without intervention, the available information in scientific databases. Performed in PubMed, ScienceDirect, Scopus, Ebscohos OvidSP and Health Library. The words used in this article: insomnia, adjustment sleep disorder, questionnaires, studies and menopause. Publications of all types were included. Seven scales were identified: Insomnia Severity Index, Athens Insomnia Scale, Pittsburgh Quality of sleep Index, Epworth Sleepiness Scale, Jenkins Sleep Scale, Basic Nordic Sleep Questionnaire and The St Mary's Hospital Sleep Questionnaire. There are validated scales in multiple languages and considered appropriate for studying sleep disorders.

  18. Relations between source parameters for large Persian earthquakes

    Directory of Open Access Journals (Sweden)

    Majid Nemati

    2015-11-01

    Full Text Available Empirical relationships for magnitude scales and fault parameters were produced using 436 Iranian intraplate earthquakes of recently regional databases since the continental events represent a large portion of total seismicity of Iran. The relations between different source parameters of the earthquakes were derived using input information which has usefully been provided from the databases after 1900. Suggested equations for magnitude scales relate the body-wave, surface-wave as well as local magnitude scales to scalar moment of the earthquakes. Also, dependence of source parameters as surface and subsurface rupture length and maximum surface displacement on the moment magnitude for some well documented earthquakes was investigated. For meeting this aim, ordinary linear regression procedures were employed for all relations. Our evaluations reveal a fair agreement between obtained relations and equations described in other worldwide and regional works in literature. The M0-mb and M0-MS equations are correlated well to the worldwide relations. Also, both M0-MS and M0-ML relations have a good agreement with regional studies in Taiwan. The equations derived from this study mainly confirm the results of the global investigations about rupture length of historical and instrumental events. However, some relations like MW-MN and MN-ML which are remarkably unlike to available regional works (e.g., American and Canadian were also found.

  19. Physics-based and statistical earthquake forecasting in a continental rift zone: the case study of Corinth Gulf (Greece)

    Science.gov (United States)

    Segou, Margarita

    2016-01-01

    I perform a retrospective forecast experiment in the most rapid extensive continental rift worldwide, the western Corinth Gulf (wCG, Greece), aiming to predict shallow seismicity (depth statistics, four physics-based (CRS) models, combining static stress change estimations and the rate-and-state laboratory law and one hybrid model. For the latter models, I incorporate the stress changes imparted from 31 earthquakes with magnitude M ≥ 4.5 at the extended area of wCG. Special attention is given on the 3-D representation of active faults, acting as potential receiver planes for the estimation of static stress changes. I use reference seismicity between 1990 and 1995, corresponding to the learning phase of physics-based models, and I evaluate the forecasts for six months following the 1995 M = 6.4 Aigio earthquake using log-likelihood performance metrics. For the ETAS realizations, I use seismic events with magnitude M ≥ 2.5 within daily update intervals to enhance their predictive power. For assessing the role of background seismicity, I implement a stochastic reconstruction (aka declustering) aiming to answer whether M > 4.5 earthquakes correspond to spontaneous events and identify, if possible, different triggering characteristics between aftershock sequences and swarm-type seismicity periods. I find that: (1) ETAS models outperform CRS models in most time intervals achieving very low rejection ratio RN = 6 per cent, when I test their efficiency to forecast the total number of events inside the study area, (2) the best rejection ratio for CRS models reaches RN = 17 per cent, when I use varying target depths and receiver plane geometry, (3) 75 per cent of the 1995 Aigio aftershocks that occurred within the first month can be explained by static stress changes, (4) highly variable performance on behalf of both statistical and physical models is suggested by large confidence intervals of information gain per earthquake and (5) generic ETAS models can adequately

  20. Instruments of health literacy used in nursing studies with hypertensive elderly

    Directory of Open Access Journals (Sweden)

    Ana Larissa Gomes Machado

    Full Text Available This study aimed to analyze nursing research regarding the instruments used to evaluate health literacy in elderly hypertensive patients. This is an integrative literature review done in the databases LILACS, PubMed, CINAHL, Scopus, and Cochrane, in June 2013. The articles, electronically available, were selected for full-text review by nurses, who assessed health literacy of elderly with hypertension. Eight studies were selected for analysis and four different instruments were used in the research. The instruments were developed according to a methodology and they were all designed to evaluate the abilities of elderly regarding reading, numeracy, pronunciation and recognition of some health-related words. The nursing research analyzed in this study revealed the gaps in care related to measures aimed to increase patient's involvement in decision-making. Also, the instruments used for measuring health literacy showed limitations, and there is no gold standard test.

  1. Sustaining Latina Student Organizations: An Exploratory Instrumental Case Study

    Science.gov (United States)

    Castellanos, Michelle

    2016-01-01

    Utilizing the exploratory case study methodology, the author examines the conditions that support and limit a Latina-based student organization at a predominately White institution of higher education. Seven organizational structures were found to influence the organization's ability to advance its aims, from interviews, documents, observations,…

  2. Acquisition of a Thermophoresis Instrument for Molecular Association Thermodynamic Studies

    Science.gov (United States)

    2015-05-20

    bound C3d with high affinity, and successfully imaged C3d on the retina of mice in vivo.8 While these two studies represent significant advances, it...work have peak excitation wavelengths in the UV spectrum. This poses a problem, as many bi- omolecules in cells and tissues exhibit autofluorescence

  3. EARTHQUAKE-INDUCED DEFORMATION STRUCTURES AND RELATED TO EARTHQUAKE MAGNITUDES

    Directory of Open Access Journals (Sweden)

    Savaş TOPAL

    2003-02-01

    Full Text Available Earthquake-induced deformation structures which are called seismites may helpful to clasify the paleoseismic history of a location and to estimate the magnitudes of the potention earthquakes in the future. In this paper, seismites were investigated according to the types formed in deep and shallow lake sediments. Seismites are observed forms of sand dikes, introduced and fractured gravels and pillow structures in shallow lakes and pseudonodules, mushroom-like silts protruding laminites, mixed layers, disturbed varved lamination and loop bedding in deep lake sediments. Earthquake-induced deformation structures, by benefiting from previous studies, were ordered according to their formations and earthquake magnitudes. In this order, the lowest eartquake's record is loop bedding and the highest one is introduced and fractured gravels in lacustrine deposits.

  4. STUDIES ON SOIL LIQUEFACTION AND SETTLEMENT IN THE URAYASU DISTRICT USING EFFECTIVE STRESS ANALYSES FOR THE 2011 EAST JAPAN GREAT EARTHQUAKE

    Science.gov (United States)

    Fukutake, Kiyoshi; Jang, Jiho

    The 2011 East Japan Great Earthquake caused soil liquefaction over a wide area. In particular, severe soil liquefaction was reported in the northern parts of the reclaimed lands around Tokyo Bay, even though the seismic intensity in this area was only about 5 on the Japan scale with low acceleration. The authors surveyed the residual settlement in the Urayasu district and then conducted effective stress analyses of areas affected and not affected by liquefaction. The analyses compared with the acceleration waves monitored with K-NET Urayasu or ground settlements surveyed. It is based on the acceleration observed on the seismic bedrocks in earthquake engineering in some other districts adjacent to Urayasu. Much of the settlement was due to the long duration of the earthquake, with further settlement resulting from the aftershock. The study shows that the affects of aftershocks need to be monitored, as well as needs for improvement of simplified liquefaction prediction methods using the factor of safety, FL.

  5. A comparison of root surface instrumentation using manual, ultrasonic and rotary instruments: an in vitro study using scanning electron microscopy.

    Science.gov (United States)

    Marda, Preeti; Prakash, Shobha; Devaraj, C G; Vastardis, S

    2012-01-01

    The commonly accepted idea concerning root planing is that excessive removal of cementum is not necessary for removal of endotoxins. The ideal instrument should enable the removal of all extraneous substances from the root surfaces, without causing any iatrogenic effects. To compare the remaining calculus, loss of tooth substance, and roughness of root surface after root planing with Gracey curette, ultrasonic instrument (Slimline insert FSI-SLI-10S), and DesmoClean rotary bur. The efficiency of calculus removal, the amount of lost tooth substance, and root surface roughness resulting from the use of hand curette, ultrasonic instrument, and rotary bur on 36 extracted mandibular incisors were examined by SEM. We used three indices to measure the changes: Remaining calculus index (RCI), Loss of tooth substance index (LTSI), and Roughness loss of tooth substance index (RLTSI). Twelve samples were treated with each instrument. The time required for instrumentation was also noted. Kruskal-Wallis ANOVA was used for multiple group comparisons and the Mann-Whitney test for group-wise comparisons. Analysis was carried out with SPSS software (version 13). The RCI and LTSI showed nonsignificant differences between the three groups. RLTSI showed a significant difference between Slimline and hand curette as well as Slimline and Desmo-Clean. Slimline showed the least mean scores for RCI, LTSI, and RLTSI. Thus, even though the difference was not statistically significant, Slimline insert was shown to be better than the other methods as assessed by the indices scores and the instrumentation time.

  6. Design and Implementation Content Validity Study: Development of an instrument for measuring Patient-Centered Communication

    Directory of Open Access Journals (Sweden)

    Vahid Zamanzadeh

    2015-06-01

    Full Text Available ABSTRACT Introduction: The importance of content validity in the instrument psychometric and its relevance with reliability, have made it an essential step in the instrument development. This article attempts to give an overview of the content validity process and to explain the complexity of this process by introducing an example. Methods: We carried out a methodological study conducted to examine the content validity of the patient-centered communication instrument through a two-step process (development and judgment. At the first step, domain determination, sampling (item generation and instrument formation and at the second step, content validity ratio, content validity index and modified kappa statistic was performed. Suggestions of expert panel and item impact scores are used to examine the instrument face validity. Results: From a set of 188 items, content validity process identified seven dimensions includes trust building (eight items, informational support (seven items, emotional support (five items, problem solving (seven items, patient activation (10 items, intimacy/friendship (six items and spirituality strengthening (14 items. Content validity study revealed that this instrument enjoys an appropriate level of content validity. The overall content validity index of the instrument using universal agreement approach was low; however, it can be advocated with respect to the high number of content experts that makes consensus difficult and high value of the S-CVI with the average approach, which was equal to 0.93. Conclusion: This article illustrates acceptable quantities indices for content validity a new instrument and outlines them during design and psychometrics of patient-centered communication measuring instrument.

  7. Adaptation of instruments developed to study the effectiveness of psychotherapeutic processes

    Directory of Open Access Journals (Sweden)

    Shushanikova, Anastasia A.

    2016-06-01

    Full Text Available The objective of the research was to adapt for use in Russian-language contexts a set of instruments that assess the effectiveness of psychotherapeutic practices. The instruments explore the effectiveness of different types of therapy, without evaluating the abstract, idealized characteristics or specifics of each approach, specialist, or therapeutic case. The adapted instruments are based on reflective data about the significance of therapeutic events, from the point of view of both the client and the therapist. We translated, edited, and adapted forms developed by John McLeod and Mick Cooper — a “Goals Form”, a “Goal Assessment Form”, a “Post-Session Form”, and a “Therapy Personalization Form”. The adaption was intended to cohere with the stylistic and cultural aspects of the Russian language. The research showed that the instruments and the methods have great potential for practical and theoretical application in qualitative studies to formulate hypotheses and to verify them in quantitative studies. The phenomenological analysis reveals the reliability, appropriateness, and validity of the adapted instruments for identifying specific meanings of the psychotherapeutic cases considered. The instruments can be used in studies exploring helpful aspects and effectiveness in different types of therapy (cognitive, existential, outdoor therapy, online counseling, etc. with different groups of clients. It is reasonable to continue the use of the Russian-language version of the instruments in further studies exploring the effectiveness of psychological practices. The adapted instruments facilitate comparison and cross-cultural studies, and formulation of meaningful hypotheses about the effectiveness and quality of the psychotherapeutic process.

  8. Money matters: Rapid post-earthquake financial decision-making

    Science.gov (United States)

    Wald, David J.; Franco, Guillermo

    2016-01-01

    Post-earthquake financial decision-making is a realm beyond that of many people. In the immediate aftermath of a damaging earthquake, billions of dollars of relief, recovery, and insurance funds are in the balance through new financial instruments that allow those with resources to hedge against disasters and those at risk to limit their earthquake losses and receive funds for response and recovery.

  9. Instrumental neutron activation analysis potentialities in archaeological ceramics studies

    International Nuclear Information System (INIS)

    Paiva, Rosemeire P.; Munita, Casimirio S.; Alves, Marcia A.

    1999-01-01

    In this work, precision and sensitivity of the determination of As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Sb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn in ceramic samples by INAA were evaluated. Two clay samples Brick Clay (NIST-SRM-697 reference material)and Ohio Red Clay (a well known clay sample) were analyzed for this purpose. Archaeological ceramic fragments from Agua Limpa Site, in Monte Alto city, SP were also analyzed. The archaeological ceramics were produced in the quotidian activities of non writing preterite societies, in sedentarization process. The ceramic chemical information are used to identify raw material sources and to study production and distribution models, which allow the reconstruction of the socio-cultural development and integration of extinguished societies. (author)

  10. Post-disaster resettlement, development and change: a case study of the 1990 Manjil earthquake in Iran.

    Science.gov (United States)

    Badri, S Ali; Asgary, Ali; Eftekhari, A R; Levy, Jason

    2006-12-01

    Planned and involuntary resettlement after natural disasters has been a major policy in post-disaster reconstruction in developing countries over the past few decades. Studies show that resettlement can result in significant adverse impacts on the resettled population. Conversely, a well-planned and managed resettlement process can produce positive long-term development outcomes. This article presents the results of a case study undertaken 11 years after the 1990 Manjil earthquake in Iran. During the reconstruction period, a policy of involuntary planned resettlement was pursued extensively. The socioeconomic changes that occurred as a consequence of this policy of involuntary resettlement are analysed. Data were collected via a questionnaire survey that involved a sample of 194 relocated households (grouped into a settlement that later became a town). The paper shows that relocated families face difficult socioeconomic challenges after relocation and regrouping. This is especially true with respect to employment, income, the empowerment of women and lifestyle issues.

  11. Study Abroad Survey Instruments: A Comparison of Survey Types and Experiences

    Science.gov (United States)

    Durrant, Marie Bradshaw; Dorius, Cassandra Rasmussen

    2007-01-01

    This study examines different survey instruments used to assess the experiences of U.S. study abroad participants. The intended audience is international and area study practitioners interested in assessing study abroad programs through postprogram interviews. An interview with the top 20 universities for number of students sent on study abroad…

  12. Multi-Sensor Observations of Earthquake Related Atmospheric Signals over Major Geohazard Validation Sites

    Science.gov (United States)

    Ouzounov, D.; Pulinets, S.; Davindenko, D.; Hattori, K.; Kafatos, M.; Taylor, P.

    2012-01-01

    We are conducting a scientific validation study involving multi-sensor observations in our investigation of phenomena preceding major earthquakes. Our approach is based on a systematic analysis of several atmospheric and environmental parameters, which we found, are associated with the earthquakes, namely: thermal infrared radiation, outgoing long-wavelength radiation, ionospheric electron density, and atmospheric temperature and humidity. For first time we applied this approach to selected GEOSS sites prone to earthquakes or volcanoes. This provides a new opportunity to cross validate our results with the dense networks of in-situ and space measurements. We investigated two different seismic aspects, first the sites with recent large earthquakes, viz.- Tohoku-oki (M9, 2011, Japan) and Emilia region (M5.9, 2012,N. Italy). Our retrospective analysis of satellite data has shown the presence of anomalies in the atmosphere. Second, we did a retrospective analysis to check the re-occurrence of similar anomalous behavior in atmosphere/ionosphere over three regions with distinct geological settings and high seismicity: Taiwan, Japan and Kamchatka, which include 40 major earthquakes (M>5.9) for the period of 2005-2009. We found anomalous behavior before all of these events with no false negatives; false positives were less then 10%. Our initial results suggest that multi-instrument space-borne and ground observations show a systematic appearance of atmospheric anomalies near the epicentral area that could be explained by a coupling between the observed physical parameters and earthquake preparation processes.

  13. Study on radon concentrations in Antarctica's instrumentation and analysis

    International Nuclear Information System (INIS)

    Silva, H.E. da.

    1990-04-01

    Continuos measurements of the natural radioactive gas sup(222)Rn are made at the Brazilian Antarctic station Comandante Ferraz (62 sup(0)S, 58 sup(0)W) to study the continental influence of air masses over the Antarctic peninsula. The technique employed in the measurements is base on the process of electrostatic collection of the ionized Polonium isotopes (the Radon decay products). The efficiency of collection is of the order of 50% to 57% for an applied electric potential of 17 kV. The collection chamber has a hemispheric shape in order to optimize the collection yield. The observed radioactivity at the Ferraz station for the period March to November 1986 and 1987 exhibited different behaviors. The year 1986 showed an average radioactivity of (2.6 ± 1.8) x 10 sup(-2) Bq.m sup(-3), while in 1987 a 50% decrease in the concentration was observed with a value of (1.44 ± 0.8) x 10 sup(-2) Bq.m sup(-3). Associated variations of wind velocity and continental aerosol loads were also observed. Periodicities in the radon time series displayed more intense peaks at 25 to 30 day periods. No seasonal trend was observed. Transient increases of radon correlated with short deicing periods. The average flux of Rn were calculated from a sampling network consisting of 20 points spread over the exposed regoliths and outcrops of the King George island, with values of 250 atoms m sup(-2) s sup(-1) for the sup(220)Rn and 7500 atoms m sup(-2) s sup(-1) for the sup(222)Rn isotope. (author)

  14. Earthquake Clusters and Spatio-temporal Migration of earthquakes in Northeastern Tibetan Plateau: a Finite Element Modeling

    Science.gov (United States)

    Sun, Y.; Luo, G.

    2017-12-01

    Seismicity in a region is usually characterized by earthquake clusters and earthquake migration along its major fault zones. However, we do not fully understand why and how earthquake clusters and spatio-temporal migration of earthquakes occur. The northeastern Tibetan Plateau is a good example for us to investigate these problems. In this study, we construct and use a three-dimensional viscoelastoplastic finite-element model to simulate earthquake cycles and spatio-temporal migration of earthquakes along major fault zones in northeastern Tibetan Plateau. We calculate stress evolution and fault interactions, and explore effects of topographic loading and viscosity of middle-lower crust and upper mantle on model results. Model results show that earthquakes and fault interactions increase Coulomb stress on the neighboring faults or segments, accelerating the future earthquakes in this region. Thus, earthquakes occur sequentially in a short time, leading to regional earthquake clusters. Through long-term evolution, stresses on some seismogenic faults, which are far apart, may almost simultaneously reach the critical state of fault failure, probably also leading to regional earthquake clusters and earthquake migration. Based on our model synthetic seismic catalog and paleoseismic data, we analyze probability of earthquake migration between major faults in northeastern Tibetan Plateau. We find that following the 1920 M 8.5 Haiyuan earthquake and the 1927 M 8.0 Gulang earthquake, the next big event (M≥7) in northeastern Tibetan Plateau would be most likely to occur on the Haiyuan fault.

  15. Psychosocial factors affecting resilience in Nepalese individuals with earthquake-related spinal cord injury: a cross-sectional study.

    Science.gov (United States)

    Bhattarai, Muna; Maneewat, Khomapak; Sae-Sia, Wipa

    2018-03-02

    One of many types of injuries following an earthquake is spinal cord injury (SCI) which is a life-long medically complex injury and high-cost health problem. Despite several negative consequences, some persons with SCI are resilient enough to achieve positive adjustment, greater acceptance, and better quality of life. Since resilience is influenced by several factors and can vary by context, it is beneficial to explore factors that affect the resilience of people who sustained spinal cord injury from the 2015 earthquake in Nepal. A descriptive cross-sectional study included 82 participants from the Spinal Injury Rehabilitation Center and communities in Nepal. Participants completed the Demographic and Injury-related Questionnaire, Connor-Davidson Resilience Scale, Multidimensional Scale of Perceived Social Support, Moorong Self-efficacy Scale, Intrinsic Spirituality Scale, and Patient Health Questionnaire-9. Pearson's correlation and point biserial correlation analyses were performed to examine associations between resilience and independent variables. A hierarchical regression analysis was used to identify the influence of certain factors. Findings indicated significant associations between resilience and social support (r = 0.42, p resilience and spirituality (r = - 0.12, p > 0.05). In hierarchical regression analysis, an overall regression model explained 46% of the variance in resilience. Self-efficacy (β = 0.28, p = 0.007) and depressive mood (β = - 0.24, p = 0.016) significantly determined resilience after controlling the effect of demographic variables. Among the demographic factors, being male significantly explained the variance in resilience (β = 0.31, p = 0.001). Multiple psychosocial and demographic factors were associated with resilience in people who sustained an earthquake-related SCI. Mental health professionals should demonstrate concern and consider such factors in allocating care in this group. Development

  16. Studies of the seismic coda using an earthquake cluster as a deeply buried seismograph array

    Science.gov (United States)

    Spudich, Paul; Bostwick, Todd

    1987-09-01

    Loosely speaking, the principle of Green's function reciprocity means that the source and receiver positions in a seismic experiment can be exchanged without affecting the observed seismograms. Consequently, the seismograms observed at a single observation location o and caused by a cluster of microearthquakes at locations {ei} are identical to the time series that would be measured by an array of stress meters emplaced at positions {ei}, recording waves generated by a source acting at o. By applying array analysis techniques like slant stacking and frequency-wave number analysis to these seismograms, we can determine the directions and velocities of the component waves as they travel in the earthquake focal region rather than at the surface. We have developed a computationally rapid plane-wave decomposition which we have applied to single-station recordings of aftershocks of the 1984 Morgan Hill, California, earthquake. The analysis is applied to data from three seismic stations having considerably different site geologies. One is a relatively hard rock station situated on Franciscan metamorphics, one is within the Calaveras fault zone, and one is on semiconsolidated sand and gravels. We define the early coda to be the part of the coda initiating immediately after the direct S wave and ending at twice the S wave lapse time. The character of the S wave and early coda varies from being impulsive at the first station to highly reverberative at the last. We examine waves in sequential time windows starting at the S wave and continuing through the early part of the coda. At all seismic stations the early coda is dominated by a persistent signal that must be caused by multiple scattering, probably within 2 km of each seismic station. Despite clear station-to-station differences in the character of the early coda, coda Q values measured in the late coda (greater than twice the S lapse time) agree well among stations, implying that the mechanisms causing the varying

  17. Feasibility study for CPR1000 incore measurement instrumentation educed from the reactor pressure vessel upper head

    International Nuclear Information System (INIS)

    Guang Jianwei; Liu Qian; Li Wenhong; Duan Yuangang

    2010-01-01

    The article discusses about the feasibility of in-core measurement instrumentation educed from the reactor pressure vessel (RPV) upper head. Incore instrumentation educed from the reactor pressure vessel upper head is one of advanced technology in the third generation nuclear power plant. This technology can reduce the manufacture problem of RPV; decrease the manufacture time effectively. Furthermore, this technology can get rid of the trouble for loss of water caused by many penetrations in the RPV bottom head, can increase security of nuclear power plant. By the description of structure analysis, comparison, maturity for four type incore instrumentation detectors, the incore instrumentation can be educed from RPV upper head, which can increase reactor's security, reduce the manufacture time, decrease group dose in refueling period. The core design ability can be enhanced through this study. (authors)

  18. A study of the modifications of nuclear instrumentation systems for JRR-2

    International Nuclear Information System (INIS)

    Azim, Mohammad; Horiki, Ooichiro; Sato, Mitsugu

    1978-04-01

    In this report a comparative study has been carried out between the original A.M.F. design and the modified design for the nuclear instrumentation systems of the Research Reactor JRR-2, at the Tokai Research Establishment of JAERI. Due to a fire accident in the control room, in July 1968, the originally designed nuclear instrumentation systems, using conventional vacuum tube circuits, were destroyed and were replaced by the modified design, incorporating solid state linear integrated circuits as basic circuit components. The results of the reactor instrumentation systems modification at JRR-2 are very encouraging as the operating efficiency of the Reactor registered an improvement of 43%. Moreover the safety aspects have been fully taken care of in the new design and the reactor is well guarded against all possible instrument failures and human errors. This report presents the basic theory of operation of the two designs alongwith a comparative safety analysis. (auth.)

  19. Investigating the Importance of 3D Structure & Topography in Seismic Deformation Modeling: Case Study of the April 2015 Nepal Earthquake

    Science.gov (United States)

    Langer, L.; Gharti, H. N.; Tromp, J.

    2017-12-01

    In recent years, observations of deformation at plate boundaries have been greatly improved by the development of techniques in space geodesy. However, models of seismic deformation remain limited and are unable to account for realistic 3D structure in topography and material properties. We demonstrate the importance of 3D structure using a spectral-element method that incorporates fault geometry, topography, and heterogeneous material properties in a (non)linear viscoelastic domain. Our method is benchmarked against Okada's analytical technique and the PyLith software package. The April 2015 Nepal earthquake is used as a case study to examine whether 3D structure can affect the predictions of seismic deformation models. We find that the inclusion of topography has a significant effect on our results.

  20. The roles of lesson study in the development of mathematics learning instrument based on learning trajectory

    Science.gov (United States)

    Misnasanti; Dien, C. A.; Azizah, F.

    2018-03-01

    This study is aimed to describe Lesson Study (LS) activity and its roles in the development of mathematics learning instruments based on Learning Trajectory (LT). This study is a narrative study of teacher’s experiences in joining LS activity. Data collecting in this study will use three methods such as observation, documentations, and deep interview. The collected data will be analyzed with Milles and Huberman’s model that consists of reduction, display, and verification. The study result shows that through LS activity, teachers know more about how students think. Teachers also can revise their mathematics learning instrument in the form of lesson plan. It means that LS activity is important to make a better learning instruments and focus on how student learn not on how teacher teach.

  1. Temporal properties of seismicity and largest earthquakes in SE Carpathians

    Directory of Open Access Journals (Sweden)

    S. Byrdina

    2006-01-01

    Full Text Available In order to estimate the hazard rate distribution of the largest seismic events in Vrancea, South-Eastern Carpathians, we study temporal properties of historical and instrumental catalogues of seismicity. First, on the basis of Generalized Extreme Value theory we estimate the average return period of the largest events. Then, following Bak et al. (2002 and Corral (2005a, we study scaling properties of recurrence times between earthquakes in appropriate spatial volumes. We come to the conclusion that the seismicity is temporally clustered, and that the distribution of recurrence times is significantly different from a Poisson process even for times largely exceeding corresponding periods of foreshock and aftershock activity. Modeling the recurrence times by a gamma distributed variable, we finally estimate hazard rates with respect to the time elapsed from the last large earthquake.

  2. Genetic influences on musical specialization: a twin study on choice of instrument and music genre.

    Science.gov (United States)

    Mosing, Miriam A; Ullén, Fredrik

    2018-05-09

    Though several studies show that genetic factors influence individual differences in musical engagement, aptitude, and achievement, no study to date has investigated whether specialization among musically active individuals in terms of choice of instrument and genre is heritable. Using a large twin cohort, we explored whether individual differences in instrument choice, instrument category, and the type of music individuals engage in can entirely be explained by the environment or are partly due to genetic influences. About 10,000 Swedish twins answered an extensive questionnaire about music-related traits, including information on the instrument and genre they played. Of those, 1259 same-sex twin pairs reported to either play an instrument or sing. We calculated the odds ratios (ORs) for concordance in music choices (if both twins played) comparing identical and nonidentical twin pairs, with significant ORs indicating that identical twins are more likely to engage in the same type of music-related behavior than are nonidentical twins. The results showed that for almost all music-related variables, the odds were significantly higher for identical twins to play the same musical instrument or music genre, suggesting significant genetic influences on such music specialization. Possible interpretations and implications of the findings are discussed. © 2018 New York Academy of Sciences.

  3. Update earthquake risk assessment in Cairo, Egypt

    Science.gov (United States)

    Badawy, Ahmed; Korrat, Ibrahim; El-Hadidy, Mahmoud; Gaber, Hanan

    2017-07-01

    The Cairo earthquake (12 October 1992; m b = 5.8) is still and after 25 years one of the most painful events and is dug into the Egyptians memory. This is not due to the strength of the earthquake but due to the accompanied losses and damages (561 dead; 10,000 injured and 3000 families lost their homes). Nowadays, the most frequent and important question that should rise is "what if this earthquake is repeated today." In this study, we simulate the same size earthquake (12 October 1992) ground motion shaking and the consequent social-economic impacts in terms of losses and damages. Seismic hazard, earthquake catalogs, soil types, demographics, and building inventories were integrated into HAZUS-MH to produce a sound earthquake risk assessment for Cairo including economic and social losses. Generally, the earthquake risk assessment clearly indicates that "the losses and damages may be increased twice or three times" in Cairo compared to the 1992 earthquake. The earthquake risk profile reveals that five districts (Al-Sahel, El Basateen, Dar El-Salam, Gharb, and Madinat Nasr sharq) lie in high seismic risks, and three districts (Manshiyat Naser, El-Waily, and Wassat (center)) are in low seismic risk level. Moreover, the building damage estimations reflect that Gharb is the highest vulnerable district. The analysis shows that the Cairo urban area faces high risk. Deteriorating buildings and infrastructure make the city particularly vulnerable to earthquake risks. For instance, more than 90 % of the estimated buildings damages are concentrated within the most densely populated (El Basateen, Dar El-Salam, Gharb, and Madinat Nasr Gharb) districts. Moreover, about 75 % of casualties are in the same districts. Actually, an earthquake risk assessment for Cairo represents a crucial application of the HAZUS earthquake loss estimation model for risk management. Finally, for mitigation, risk reduction, and to improve the seismic performance of structures and assure life safety

  4. Towards Developing Science of Survival (SOS) Pamphlets for "Typhoon, Flashflood, Storm Surge and Tsunami" and for "Earthquakes and Their Aftermath": A Pilot Study

    Science.gov (United States)

    Nivera, Gladys; Camacho, Vic Marie; Sia, Shila Rose; Avilla, Ruel; Butron, Benilda; Fernandez, Eisha Vienna; Pastor, Crist John; Reyes, Allan; Palomar, Brando

    2017-01-01

    The catastrophic devastation from recent natural calamities in the Philippines such as Typhoon Yolanda and Central Visayas earthquake in 2013 had made disaster preparedness a primary concern in the country. Prompted by the critical need to use science to save lives, this study developed Science of Survival (SOS) pamphlets titled "When the…

  5. Utilities/industries joint study on seismic isolation systems for LWR: Part II. Observed behaviors of base-isolated general buildings under real earthquakes

    International Nuclear Information System (INIS)

    Matsumura, Takao; Sato, Shoji; Kato, Muneaki

    1989-01-01

    This paper describes the observed behavior of base-isolated buildings under real earthquake conditions. These buildings were constructed by five construction companies participating in the Joint Study on Seismic Isolation Systems for lightwater reactors. All the buildings are medium- or low-height buildings of reinforced-concrete structures with combinations of laminated rubber bearing or sliding bearings and various damping devices

  6. Mapping Tectonic Stress Using Earthquakes

    International Nuclear Information System (INIS)

    Arnold, Richard; Townend, John; Vignaux, Tony

    2005-01-01

    An earthquakes occurs when the forces acting on a fault overcome its intrinsic strength and cause it to slip abruptly. Understanding more specifically why earthquakes occur at particular locations and times is complicated because in many cases we do not know what these forces actually are, or indeed what processes ultimately trigger slip. The goal of this study is to develop, test, and implement a Bayesian method of reliably determining tectonic stresses using the most abundant stress gauges available - earthquakes themselves.Existing algorithms produce reasonable estimates of the principal stress directions, but yield unreliable error bounds as a consequence of the generally weak constraint on stress imposed by any single earthquake, observational errors, and an unavoidable ambiguity between the fault normal and the slip vector.A statistical treatment of the problem can take into account observational errors, combine data from multiple earthquakes in a consistent manner, and provide realistic error bounds on the estimated principal stress directions.We have developed a realistic physical framework for modelling multiple earthquakes and show how the strong physical and geometrical constraints present in this problem allow inference to be made about the orientation of the principal axes of stress in the earth's crust

  7. Earthquake damage to underground facilities

    International Nuclear Information System (INIS)

    Pratt, H.R.; Hustrulid, W.A.; Stephenson, D.E.

    1978-11-01

    The potential seismic risk for an underground nuclear waste repository will be one of the considerations in evaluating its ultimate location. However, the risk to subsurface facilities cannot be judged by applying intensity ratings derived from the surface effects of an earthquake. A literature review and analysis were performed to document the damage and non-damage due to earthquakes to underground facilities. Damage from earthquakes to tunnels, s, and wells and damage (rock bursts) from mining operations were investigated. Damage from documented nuclear events was also included in the study where applicable. There are very few data on damage in the subsurface due to earthquakes. This fact itself attests to the lessened effect of earthquakes in the subsurface because mines exist in areas where strong earthquakes have done extensive surface damage. More damage is reported in shallow tunnels near the surface than in deep mines. In mines and tunnels, large displacements occur primarily along pre-existing faults and fractures or at the surface entrance to these facilities.Data indicate vertical structures such as wells and shafts are less susceptible to damage than surface facilities. More analysis is required before seismic criteria can be formulated for the siting of a nuclear waste repository

  8. Source complexity and the physical mechanism of the 2015 Mw 7.9 Bonin Island earthquake

    Science.gov (United States)

    Chen, Y.; Meng, L.; Wen, L.

    2015-12-01

    The 30 May 2015 Mw 7.9 Bonin Island earthquake is the largest instrument-recorded deep-focus earthquake in the Izu-Bonin arc. It occurred approximately 100 km deeper than the previous seismicity, in the region unlikely to be within the core of the subducting Izu-Bonin slab. The earthquake provides an unprecedented opportunity to understand the unexpected occurrence of such isolated deep earthquakes. Multiple source inversion of the P, SH, pP and sSH phases and a novel fully three-dimensional back-projection of P and pP phases are applied to study the coseismic source process. The subevents locations and short-period energy radiations both show a L-shape bilateral rupture propagating initially in the SW direction then in the NW direction with an average rupture speed of 2.0 km/s. The decrease of focal depth on the NW branch suggests that the rupture is consistent with a single sub-horizontal plane inferred from the GCMT solution. The multiple source inversion further indicates slight variation of the focal strikes of the sub-events with the curvature of the subducting Izu-Bonin slab. The rupture is confined within an area of 20 km x 35 km, rather compact compared with the shallow earthquake of similar magnitude. The earthquake is of high stress drop on the order of 100 MPa and a low seismic efficiency of 0.19, indicating large frictional heat dissipation. The only aftershock is 11 km to the east of the mainshock hypocenter and 3 km away from the centroid of the first sub-event. Analysis of the regional tomography and nearby seismicity suggests that the earthquake may occur at the edge/periphery of the bending slab and is unlikely to be within the "cold" metastable olivine wedge. Our results suggest the spontaneous nucleation of the thermally induced shear instability is a possible mechanism for such isolated deep earthquakes.

  9. Keeping the History in Historical Seismology: The 1872 Owens Valley, California Earthquake

    International Nuclear Information System (INIS)

    Hough, Susan E.

    2008-01-01

    The importance of historical earthquakes is being increasingly recognized. Careful investigations of key pre-instrumental earthquakes can provide critical information and insights for not only seismic hazard assessment but also for earthquake science. In recent years, with the explosive growth in computational sophistication in Earth sciences, researchers have developed increasingly sophisticated methods to analyze macroseismic data quantitatively. These methodological developments can be extremely useful to exploit fully the temporally and spatially rich information source that seismic intensities often represent. For example, the exhaustive and painstaking investigations done by Ambraseys and his colleagues of early Himalayan earthquakes provides information that can be used to map out site response in the Ganges basin. In any investigation of macroseismic data, however, one must stay mindful that intensity values are not data but rather interpretations. The results of any subsequent analysis, regardless of the degree of sophistication of the methodology, will be only as reliable as the interpretations of available accounts - and only as complete as the research done to ferret out, and in many cases translate, these accounts. When intensities are assigned without an appreciation of historical setting and context, seemingly careful subsequent analysis can yield grossly inaccurate results. As a case study, I report here on the results of a recent investigation of the 1872 Owen's Valley, California earthquake. Careful consideration of macroseismic observations reveals that this event was probably larger than the great San Francisco earthquake of 1906, and possibly the largest historical earthquake in California. The results suggest that some large earthquakes in California will generate significantly larger ground motions than San Andreas fault events of comparable magnitude

  10. Medical Requirements During a Natural Disaster: A Case Study on WhatsApp Chats Among Medical Personnel During the 2015 Nepal Earthquake.

    Science.gov (United States)

    Basu, Moumita; Ghosh, Saptarshi; Jana, Arnab; Bandyopadhyay, Somprakash; Singh, Ravikant

    2017-12-01

    The objective of this study was to explore a log of WhatsApp messages exchanged among members of the health care group Doctors For You (DFY) while they were providing medical relief in the aftermath of the Nepal earthquake in April 2015. Our motivation was to identify medical resource requirements during a disaster in order to help government agencies and other responding organizations to be better prepared in any upcoming disaster. A large set of WhatsApp (WhatsApp Inc, Mountain View, CA) messages exchanged among DFY members during the Nepal earthquake was collected and analyzed to identify the medical resource requirements during different phases of relief operations. The study revealed detailed phase-wise requirements for various types of medical resources, including medicines, medical equipment, and medical personnel. The data also reflected some of the problems faced by the medical relief workers in the earthquake-affected region. The insights from this study may help not only the Nepalese government, but also authorities in other earthquake-prone regions of the world to better prepare for similar disasters in the future. Moreover, real-time analysis of such online data during a disaster would aid decision-makers in dynamically formulating resource-mapping strategies. (Disaster Med Public Health Preparedness. 2017;11:652-655).

  11. Pain after earthquake

    Directory of Open Access Journals (Sweden)

    Angeletti Chiara

    2012-06-01

    Full Text Available Abstract Introduction On 6 April 2009, at 03:32 local time, an Mw 6.3 earthquake hit the Abruzzi region of central Italy causing widespread damage in the City of L Aquila and its nearby villages. The earthquake caused 308 casualties and over 1,500 injuries, displaced more than 25,000 people and induced significant damage to more than 10,000 buildings in the L'Aquila region. Objectives This observational retrospective study evaluated the prevalence and drug treatment of pain in the five weeks following the L'Aquila earthquake (April 6, 2009. Methods 958 triage documents were analysed for patients pain severity, pain type, and treatment efficacy. Results A third of pain patients reported pain with a prevalence of 34.6%. More than half of pain patients reported severe pain (58.8%. Analgesic agents were limited to available drugs: anti-inflammatory agents, paracetamol, and weak opioids. Reduction in verbal numerical pain scores within the first 24 hours after treatment was achieved with the medications at hand. Pain prevalence and characterization exhibited a biphasic pattern with acute pain syndromes owing to trauma occurring in the first 15 days after the earthquake; traumatic pain then decreased and re-surged at around week five, owing to rebuilding efforts. In the second through fourth week, reports of pain occurred mainly owing to relapses of chronic conditions. Conclusions This study indicates that pain is prevalent during natural disasters, may exhibit a discernible pattern over the weeks following the event, and current drug treatments in this region may be adequate for emergency situations.

  12. A Study on distinguishing seismic waves caused by natural earthquakes and underground nuclear explosion within North Korean Context

    Science.gov (United States)

    Premlet, B.; Sabu, S.; Kamarudheen, R.; Subair, S.

    2017-12-01

    Since the first nuclear test on 15 July 1945 , there have been over 2,051 other weapon tests around the world . The waveforms of a natural earthquake which generates strong S waves and an underground explosion which is dominated by P waves were distinguished from the analysis of data corresponding to a 2005 M5.0 Earthquake and a 2016 North Korean nuclear test , both at similar distances from seismometer . Further differences between the seismograms were evaluated and successfully distinguished between the origins of the elastic waves through the data using Moment Tensor Solution using stations BJT , HIA and INCN . North Korea has developed a nuclear fuel cycle capability and has both plutonium and enriched uranium programs at Pyongyang . Seismic recordings of vertical ground motion at Global Seismographic Network station IC.MDJ of the 4 seismic events at Punggye-ri , North Korea , which occurred on the 9th of October 2006 , 25th of May 2009, 12th of February 2013 and on the 6th of January and 9th of September , 2016 were examined and the P waves of these seismic waves , which show very similar wave form , were inspected and compared to the seismic data of the latest underground nuclear test on the 3rd of September 2017 at 03:30 UTC at the same site which is many times more powerful than the previous tests . The country , which is the only nation to have tested nuclear weapons in this millennium , has successfully prevented the release of radioactive isotopes and hampered data collection but further studies were done using acoustic data which was analysed from sonograms of the 4 North Korean tests at station MDJ. The latest explosion data from 3rd September was also compared to 42 presumed underground explosions which occurred in China , India , the U.S.S.R , Iran , Turkey and recorded at Arkansas Seismic Network.

  13. Instrumentation for the study of low emittance tuning and beam dynamics at CESR

    Science.gov (United States)

    Billing, M. G.; Dobbins, J. A.; Forster, M. J.; Kreinick, D. L.; Meller, R. E.; Peterson, D. P.; Ramirez, G. A.; Rendina, M. C.; Rider, N. T.; Sagan, D. C.; Shanks, J.; Sikora, J. P.; Stedinger, M. G.; Strohman, C. R.; Williams, H. A.; Palmer, M. A.; Holtzapple, R. L.; Flanagan, J.

    2017-11-01

    The Cornell Electron-positron Storage Ring (CESR) has been converted from a High Energy Physics electron-positron collider to operate as a dedicated synchrotron light source for the Cornell High Energy Synchrotron Source (CHESS) and to conduct accelerator physics research as a test accelerator, capable of studying topics relevant to future damping rings, colliders and light sources. Some of the specific topics that were targeted for the initial phase of operation of the storage ring in this mode for CESR as a Test Accelerator (CesrTA) included 1) tuning techniques to produce low emittance beams, 2) the study of electron cloud development in a storage ring and 3) intra-beam scattering effects. The complete conversion of CESR to CesrTA occurred over a several year period, described elsewhere [1-3]. In addition to instrumentation for the storage ring, which was created for CesrTA, existing instrumentation was modified to facilitate the entire range of investigations to support these studies. Procedures were developed, often requiring coordinated measurements among different instruments [4]. This paper describes the instruments utilized for the study of beam dynamics during the operation of CesrTA. The treatment of these instruments will remain fairly general in this paper as it focusses on an overview of the instruments themselves. Their interaction and inter-relationships during sequences of observations is found in a companion paper describing the associated measurement techniques. More detailed descriptions and detailed operational performance for some of the instrumentation may be found elsewhere and these will be referenced in the related sections of this paper.

  14. Psychometric properties of assessment instruments for autism spectrum disorder: a systematic review of Brazilian studies

    Directory of Open Access Journals (Sweden)

    Bárbara Backes

    2014-07-01

    Full Text Available Objective To systematically review the scientific literature on the psychometric properties of international instruments for the assessment of autism spectrum disorder (ASD in the Brazilian population. Methods A search of bibliographic references was conducted in six electronic databases: PsycINFO, PubMed, IndexPsi, Lilacs, Capes (theses and dissertations and SciELO. The studies were selected by two independent researchers. Results The procedure identified 11 studies of the Brazilian population that encompassed six ASD assessment tools. Given the information provided, the adaptation of the M-CHAT, a screening instrument, was the best conducted. All steps of the adaptation process were described and the changes made to the final version of the instrument were presented, which was not addressed in other studies. In terms of reliability, all of the instruments that assessed internal consistency showed adequate values. In addition, the ADI-R and the CARS adaptations also satisfactorily contemplated inter-rater reliability and test-retest indices, respectively. Finally, all studies aiming to validate instruments showed evidence of validity and sensitivity, and specificity values above 0.90 were observed in the ASQ, ADI-R and ABC. Conclusion Considering both the psychometric aspects and the copyright information, the screening instrument that currently appears to be best indicated for clinical and research use is the M-CHAT. It was also noticed that there are still no specific ASD diagnostic tools available for use in Brazil. This lack of diagnostic instruments consists in a critical situation for the improvement of clinical practice and the development of research in this area.

  15. Evolving Curricular Models in Culinary Arts: An Instrumental Case Study of a Technical Field

    Science.gov (United States)

    Cossio, Allison

    2016-01-01

    The purpose of this research study was to examine how chefs and other individuals in the food industry understood the field of culinary arts. This study used an instrumental case study with purposeful sampling of multiple cases. Through a series of open-ended interviews using snowball-sampling strategy that concluded with 45 participants sharing…

  16. Earthquake likelihood model testing

    Science.gov (United States)

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

    2007-01-01

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

  17. Recognition of earthquake-prone nodes, a case study for North Vietnam (M ⩾ 5.0

    Directory of Open Access Journals (Sweden)

    Nguyen Huu Tuyen

    2012-05-01

    Full Text Available Morphostructural nodes in North Vietnam are delineated with the morphostructural zoning (MZ method, and classified into seismogenic and non-seismogenic nodes. The compiled morphostructural map (scale 1: 1000000 shows a three-level hierarchical structure of blocks, boundary zones, and nodes. The identified nodes are classified with the pattern-recognition algorithm CORA-3 into those that are prone to generate M ⩾ 5.0 earthquakes and those that are not. Some of the earthquake-prone nodes coincide with epicenters of M ⩾ 5.0 earthquakes that have occurred; others may coincide with such events in the future.

  18. Using Spatial Multi-Criteria Analysis and Ranking Tool (SMART in earthquake risk assessment: a case study of Delhi region, India

    Directory of Open Access Journals (Sweden)

    Nishant Sinha

    2016-03-01

    Full Text Available This article is aimed at earthquake hazard, vulnerability and risk assessment as a case study to demonstrate the applicability of Spatial Multi-Criteria Analysis and Ranking Tool (SMART, which is based on Saaty's multi-criteria decision analysis (MCDA technique. The three specific study sites of Delhi were chosen for research as it corresponds to a typical patch of the urban environs, completely engrossed with residential, commercial and industrial units. The earthquake hazard affecting components are established in the form of geographic information system data-set layers including seismic zone, peak ground acceleration (PGA, soil characteristics, liquefaction potential, geological characteristics, land use, proximity to fault and epicentre. The physical vulnerability layers comprising building information, namely number of stories, year-built range, area, occupancy and construction type, derived from remote sensing imagery, were only considered for the current research. SMART was developed for earthquake risk assessment, and weights were derived both at component and its element level. Based on weighted overlay techniques, the earthquake hazard and vulnerability layers were created from which the risk maps were derived through multiplicative analysis. The developed risk maps may prove useful in decision-making process and formulating risk mitigation measures.

  19. Gender differences in the relationship between maladaptive behaviours and post-traumatic stress disorder. A study on 900 L’Aquila 2009 earthquake survivors.

    Directory of Open Access Journals (Sweden)

    Liliana eDell'Osso

    2013-01-01

    Full Text Available Background: Post-traumatic stress disorder (PTSD represents one of the most frequently psychiatric sequelae to earthquake exposure. Increasing evidence suggests the onset of maladaptive behaviors among veterans and adolescents with PTSD, with specific gender differences emerging in the latter. Aims of the present study were to investigate the relationships between maladaptive behaviours and PTSD in earthquake survivors, besides the gender differences in the type and prevalence of maladaptive behaviours and their association with PTSD. Methods: 900 residents of the town of L’Aquila who experienced the earthquake of April 6th 2009 (Richter Magnitude 6.3 were assessed by means of the Trauma and Loss Spectrum Self Report (TALS-SR.Results: Significantly higher maladaptive behaviour prevalence rates were found among subjects with PTSD. A statistically significant association was found between male gender and the presence of at least one maladaptive behaviour among PTSD survivors. In the latter, significant correlations emerged between maladaptive coping and symptoms of re-experiencing, avoidance and numbing and arousal in women, while only between maladaptive coping and avoidance and numbing in men. Conclusions: Our results show high rates of maladaptive behaviours among earthquake survivors with PTSD suggesting a greater severity among men. Interestingly, post-traumatic stress symptomatology appears to be a better correlate of these behaviours among women than among men, suggesting the need for further studies based on a gender approach.

  20. Gender Differences in the Relationship between Maladaptive Behaviors and Post-Traumatic Stress Disorder. A Study on 900 L' Aquila 2009 Earthquake Survivors.

    Science.gov (United States)

    Dell'osso, Liliana; Carmassi, Claudia; Stratta, Paolo; Massimetti, Gabriele; Akiskal, Kareen K; Akiskal, Hagop S; Maremmani, Icro; Rossi, Alessandro

    2012-01-01

    Post-traumatic stress disorder (PTSD) represents one of the most frequently psychiatric sequelae to earthquake exposure. Increasing evidence suggests the onset of maladaptive behaviors among veterans and adolescents with PTSD, with specific gender differences emerging in the latter. Aims of the present study were to investigate the relationships between maladaptive behaviors and PTSD in earthquake survivors, besides the gender differences in the type and prevalence of maladaptive behaviors and their association with PTSD. 900 residents of the town of L'Aquila who experienced the earthquake of April 6th 2009 (Richter Magnitude 6.3) were assessed by means of the Trauma and Loss Spectrum-Self Report (TALS-SR). Significantly higher maladaptive behavior prevalence rates were found among subjects with PTSD. A statistically significant association was found between male gender and the presence of at least one maladaptive behavior among PTSD survivors. Further, among survivors with PTSD significant correlations emerged between maladaptive coping and symptoms of re-experiencing, avoidance and numbing, and arousal in women, while only between maladaptive coping and avoidance and numbing in men. Our results show high rates of maladaptive behaviors among earthquake survivors with PTSD suggesting a greater severity among men. Interestingly, post-traumatic stress symptomatology appears to be a better correlate of these behaviors among women than among men, suggesting the need for further studies based on a gender approach.

  1. Roles of Radon-222 and other natural radionuclides in earthquake prediction

    International Nuclear Information System (INIS)

    Smith, A.R.; Wollenberg, H.A.; Mosier, D.F.

    1980-01-01

    The concentration of 222 Rn in subsurface waters is one of the natural parameters being investigated to help develop the capability to predict destructive earthquakes. Since 1966, scientists in several nations have sought to link radon variations with ongoing seismic activity, primarily through the dilatancy model for earthquake occurrences. Within the range of these studies, alpha-, beta-, and gamma-radiation detection techniques have been used in both discrete-sampling and continiuous-monitoring programs. These measured techniques are reviewed in terms of instrumentation adapted to seismic-monitoring purposes. A recent Lawrence Berkeley Laboratory study conducted in central California incorporated discrete sampling of wells in the aftershock area of the 1975 Oroville earthquake and continuous monitoring of water radon in a well on the San Andreas Fault. The results presented show short-term radon variations that may be associated with aftershocks and diurnal changes that may reflect earth tidal forces

  2. Rapid Seismic Deployment for Capturing Aftershocks of the September 2017 Tehuantepec, Mexico (M=8.1) and Morelos-Puebla (M=7.1), Mexico Earthquakes

    Science.gov (United States)

    Velasco, A. A.; Karplus, M. S.; Dena, O.; Gonzalez-Huizar, H.; Husker, A. L.; Perez-Campos, X.; Calo, M.; Valdes, C. M.

    2017-12-01

    The September 7 Tehuantepec, Mexico (M=8.1) and the September 19 Morelos-Puebla, Mexico (M=7.1) earthquakes ruptured with extensional faulting within the Cocos Plate at 70-km and 50-km depth, as it subducts beneath the continental North American Plate. Both earthquakes caused significant damage and loss of life. These events were followed by a M=6.1 extensional earthquake at only 10-km depth in Oaxaca on September 23, 2017. While the Morelos-Puebla earthquake was likely too far away to be statically triggered by the Tehuantepec earthquake, initial Coulomb stress analyses show that the M=6.1 event may have been an aftershock of the Tehuantepec earthquake. Many questions remain about these earthquakes, including: Did the Cocos Plate earthquakes load the upper plate, and could they possibly trigger an equal or larger earthquake on the plate interface? Are these the result of plate bending? Do the aftershocks migrate to the locked zone in the subduction zone? Why did the intermediate depth earthquakes create so much damage? Are these earthquakes linked by dynamic stresses? Is it possible that a potential slow-slip event triggered both events? To address some of these questions, we deployed 10 broadband seismometers near the epicenter of the Tehuantepec, Mexico earthquake and 51 UTEP-owned nodes (5-Hz, 3-component geophones) to record aftershocks and augment networks deployed by the Universidad Nacional Autónoma de México (UNAM). The 10 broadband instruments will be deployed for 6 months, while the nodes were deployed 25 days. The relative ease-of-deployment and larger numbers of the nodes allowed us to deploy them quickly in the area near the M=6.1 Oaxaca earthquake, just a few days after that earthquake struck. We deployed them near the heavily-damaged cities of Juchitan, Ixtaltepec, and Ixtepec as well as in Tehuantepec and Salina Cruz, Oaxaca in order to test their capabilities for site characterization and aftershock studies. This is the first test of these

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

    Science.gov (United States)

    Satake, Kenji

    2015-10-28

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

  4. Fault lubrication during earthquakes.

    Science.gov (United States)

    Di Toro, G; Han, R; Hirose, T; De Paola, N; Nielsen, S; Mizoguchi, K; Ferri, F; Cocco, M; Shimamoto, T

    2011-03-24

    The determination of rock friction at seismic slip rates (about 1 m s(-1)) is of paramount importance in earthquake mechanics, as fault friction controls the stress drop, the mechanical work and the frictional heat generated during slip. Given the difficulty in determining friction by seismological methods, elucidating constraints are derived from experimental studies. Here we review a large set of published and unpublished experiments (∼300) performed in rotary shear apparatus at slip rates of 0.1-2.6 m s(-1). The experiments indicate a significant decrease in friction (of up to one order of magnitude), which we term fault lubrication, both for cohesive (silicate-built, quartz-built and carbonate-built) rocks and non-cohesive rocks (clay-rich, anhydrite, gypsum and dolomite gouges) typical of crustal seismogenic sources. The available mechanical work and the associated temperature rise in the slipping zone trigger a number of physicochemical processes (gelification, decarbonation and dehydration reactions, melting and so on) whose products are responsible for fault lubrication. The similarity between (1) experimental and natural fault products and (2) mechanical work measures resulting from these laboratory experiments and seismological estimates suggests that it is reasonable to extrapolate experimental data to conditions typical of earthquake nucleation depths (7-15 km). It seems that faults are lubricated during earthquakes, irrespective of the fault rock composition and of the specific weakening mechanism involved.

  5. On Strong Positive Frequency Dependencies of Quality Factors in Local-Earthquake Seismic Studies

    Science.gov (United States)

    Morozov, Igor B.; Jhajhria, Atul; Deng, Wubing

    2018-03-01

    Many observations of seismic waves from local earthquakes are interpreted in terms of the frequency-dependent quality factor Q( f ) = Q0 f^{η } , where η is often close to or exceeds one. However, such steep positive frequency dependencies of Q require careful analysis with regard to their physical consistency. In particular, the case of η = 1 corresponds to frequency-independent (elastic) amplitude decays with time and consequently requires no Q-type attenuation mechanisms. For η > 1, several problems with physical meanings of such Q-factors occur. First, contrary to the key premise of seismic attenuation, high-frequency parts of the wavefield are enhanced with increasing propagation times relative to the low-frequency ones. Second, such attenuation cannot be implemented by mechanical models of wave-propagating media. Third, with η > 1, the velocity dispersion associated with such Q(f) occurs over unrealistically short frequency range and has an unexpected oscillatory shape. Cases η = 1 and η > 1 are usually attributed to scattering; however, this scattering must exhibit fortuitous tuning into the observation frequency band, which appears unlikely. The reason for the above problems is that the inferred Q values are affected by the conventional single-station measurement procedure. Both parameters Q 0 and are apparent, i.e., dependent on the selected parameterization and inversion method, and they should not be directly attributed to the subsurface. For η ≈ 1, parameter Q 0 actually describes the frequency-independent amplitude decay in access of some assumed geometric spreading t -α , where α is usually taken equal one. The case η > 1 is not allowed physically and could serve as an indicator of problematic interpretations. Although the case 0 < η < 1 is possible, its parameters Q 0 and may also be biased by the measurement procedure. To avoid such difficulties of Q-based approaches, we recommend measuring and interpreting the amplitude-decay rates

  6. Earthquake Triggering in the September 2017 Mexican Earthquake Sequence

    Science.gov (United States)

    Fielding, E. J.; Gombert, B.; Duputel, Z.; Huang, M. H.; Liang, C.; Bekaert, D. P.; Moore, A. W.; Liu, Z.; Ampuero, J. P.

    2017-12-01

    Southern Mexico was struck by four earthquakes with Mw > 6 and numerous smaller earthquakes in September 2017, starting with the 8 September Mw 8.2 Tehuantepec earthquake beneath the Gulf of Tehuantepec offshore Chiapas and Oaxaca. We study whether this M8.2 earthquake triggered the three subsequent large M>6 quakes in southern Mexico to improve understanding of earthquake interactions and time-dependent risk. All four large earthquakes were extensional despite the the subduction of the Cocos plate. The traditional definition of aftershocks: likely an aftershock if it occurs within two rupture lengths of the main shock soon afterwards. Two Mw 6.1 earthquakes, one half an hour after the M8.2 beneath the Tehuantepec gulf and one on 23 September near Ixtepec in Oaxaca, both fit as traditional aftershocks, within 200 km of the main rupture. The 19 September Mw 7.1 Puebla earthquake was 600 km away from the M8.2 shock, outside the standard aftershock zone. Geodetic measurements from interferometric analysis of synthetic aperture radar (InSAR) and time-series analysis of GPS station data constrain finite fault total slip models for the M8.2, M7.1, and M6.1 Ixtepec earthquakes. The early M6.1 aftershock was too close in time and space to the M8.2 to measure with InSAR or GPS. We analyzed InSAR data from Copernicus Sentinel-1A and -1B satellites and JAXA ALOS-2 satellite. Our preliminary geodetic slip model for the M8.2 quake shows significant slip extended > 150 km NW from the hypocenter, longer than slip in the v1 finite-fault model (FFM) from teleseismic waveforms posted by G. Hayes at USGS NEIC. Our slip model for the M7.1 earthquake is similar to the v2 NEIC FFM. Interferograms for the M6.1 Ixtepec quake confirm the shallow depth in the upper-plate crust and show centroid is about 30 km SW of the NEIC epicenter, a significant NEIC location bias, but consistent with cluster relocations (E. Bergman, pers. comm.) and with Mexican SSN location. Coulomb static stress

  7. A Poisson method application to the assessment of the earthquake hazard in the North Anatolian Fault Zone, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Türker, Tuğba, E-mail: tturker@ktu.edu.tr [Karadeniz Technical University, Department of Geophysics, Trabzon/Turkey (Turkey); Bayrak, Yusuf, E-mail: ybayrak@agri.edu.tr [Ağrı İbrahim Çeçen University, Ağrı/Turkey (Turkey)

    2016-04-18

    North Anatolian Fault (NAF) is one from the most important strike-slip fault zones in the world and located among regions in the highest seismic activity. The NAFZ observed very large earthquakes from the past to present. The aim of this study; the important parameters of Gutenberg-Richter relationship (a and b values) estima