DOCSLIB.ORG

Earthquake Prediction Research in China: Status and Prospects

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Earthquake Prediction Research in China: Status and Prospects J. Phys. Earth, 34, Suppl., S1-S11, 1 986 EARTHQUAKE PREDICTION RESEARCH IN CHINA: STATUS AND PROSPECTS Zhangli CHEN State Seismological Bureau, Beijing, China (Received June 22, 1985; Revised May 22, 1986) The initial understandings about time and space distribution of major earthquakes and earthquake precursors, and prediction achieved for the past 18 years in China are summarized. Two major aspects of the fundamental understandings are: 1) Before most of the strong shocks, particularly those with magnitude over 7 occurring within an area under the detectability of a network, varieties of anomalous phenomena are observed. 2) Because of the complicated continental crustal structures, the temporal and spatial distributions of the continental seismicity in China are rather complex, but there are some regularities, and some unique dynamic patterns such as block-like, stripe-like, and diversified distributions of earthquakes. The problems of earthquake prediction are identified. They are mainly caused by 1) non-uniqueness of the relation between anomalous variations and earthquake precursors, 2) complexity of the relation between local and regional anomalies, and 3) diversity of possible earthquake precursors. And how to improve the level of earthquake prediction, topics to be further studied, and the key work to be carried out are also discussed. Efforts should be directed to 1) systematic evaluation and in-depth research of various prediction methods, 2) setting up the optimum monitoring network and appropriate data processing systems, 3) profound fundamental research, and 4) comprehensive research on earthquake precursors. 1. Introduction The fairly comprehensive earthquake prediction research program in China has been formulated officially and put into operation gradually since the 1966 Xingtai earthquake. A number of great earthquakes which have occurred in Mainland China in the recent 18 years have provided a rare opportunity and very useful sites for both Chinese seismological workers and scientists from other countries to study the earthquake prediction problem and to make repeated experiments. Therefore, there have been great development in earthquake prediction research, and increased understanding of the complexity of earth- quake predictions. In particular, the successful predictions of the Haicheng and other earthquakes, and the failure to predict the Tangshan and other shocks have made a great impact on, and fostered various opinions about, the future of earthquake prediction. The scientific assessments of the earthquake prediction research in China will be very helpful not only in working out a new earthquake prediction research program in China, but also in promoting further worldwide earthquake prediction studies. S1 S2 Z. CHEN 2. Extensive Studies and Fundamental Understandings Earthquake prediction research in China began with the prediction studies of aftershocks in the Xingtai epicentral area, and was gradually expanded toward. North China, Sichuan-Yunnan, and other main seismic areas in China. The prediction work in China is characterized by interdisciplinary comprehensive research in multiple areas, as well as by the joint efforts of experts and non-professionals, and by bilateral efforts towards basic research and practical earthquake prediction. The areas for earthquake prediction research include geology, geophysics, geodesy, geochemistry, biology, astronomy, me- teorology, 'and mathematics. There are about 20 kinds of items for observational work, such as seismic activity, crustal deformation, underground water level, hydrochemical composition, earth resistivity, geomagnetism, gravity, in-situ stress, etc. With the various data accumulated, studies have been conducted on time-space-magnitude distributions of regional seismicity (DING, 1984; DENGet al., 1980; SUNet al., 1984; MA et al., 1980, 1982; XU, 1984), features of possible seismic precursors and corresponding prediction methods (MA et al., 1982; CI-IENet al., 1981; Liu et al., 1984; Lu et al., 1984; ZHU et al., 1977; ZHEN and HU, 1978; FENG et al., 1976; MEI et al., 1982; JIANG, 1980), as well as experimental and theoretical work performed on the physical processes of an earthquake. Meanwhile, comprehensive research has been carried out on the basis of field geological investigations, deep seismic sounding results, geological interpretations of satellite images, and other techniques, to understand the geological conditions for an earthquake occur- rence. In addition, there have been numerous discussions on the relation between Chinese seismicity and global seismicity, and on the relationships of abnormal meteorological changes, variations of the Earth's rotations, polar wandering, solar activity, and other environmental factors, to the seismic activity (LI et al., 1973; FU, 1981; LIU and LIU, 1982, XUE,1982). The research results have been continuously applied to prediction experiments. Hence a comprehensive prediction method combined with multi-disciplinary approaches, integrated analyses with point and areal data, studies of tectonic background combined with geodynamic data, and physical pattern analysis integrated with statistics are gradually developing. From this 18-year process, the earthquake prediction work in China includes two developmental periods from 1966 to 1976, and from 1977 to the present. During the first period, the continental seismicity in China was featured by high frequency and large magnitude, and the professional and amateur monitoring networks were set up and expanded rapidly. In addition, the perceptual understandings were gained very quickly with the frequent occurrences of large earthquakes. During the second period, the seismicity seems to be relatively low. However, under such a new situation of seismic activity, the existing knowledge was challenged by the new problems encountered, and the scientific and technical advancement has further promoted the in-depth earthquake prediction research. On the one hand, a portion of the seismic stations have been upgraded technically, with construction of the fast data transmission and real time processing systems. As a result, 6 regional seismic data processing centers with telemetering via telephone line have been established in Beijing, Shanghai, Shenyang, Kunming, Chendu, and Lanzhou. The amateur earthquake prediction and observation networks have been Earthquake Prediction Research in China S3 restructured and readjusted with the concentrated efforts of mass prediction and mass prevention focused in some key areas. On the other hand, the seismological research has been further strengthened. The similarity and dissimilarity of the possible precursors before the earthquakes, especially those before several large shocks of M (magnitude) over 7, have been reviewed; and the theoretical studies and laboratory experiments have been conducted on the environmental and dynamic conditions for an earthquake occurrence, the seismo- genic process, and the precursory mechanisms, so that the existing understandings will be supplemented and further developed. In summary, the two main aspects of the fundamen- tal understandings gained within the past 18 years are as follows: 1) Before most of the strong shocks, particularly those with M over 7, which occur within an area under the detectability of a network, there are varieties of anomalous phenomena. According to the time when the anomalies appear and their morphology, these phenomena can be split into 4 categories, and in turn, the time period for an earthquake preparation and prediction can also be divided into 4 corresponding intervals (Table 1). It should be noted that various anomalies listed in Table 1 are not observed before all earthquakes. Some of the anomalies (asterisks in the table) have been repeatedly observed. However, it is hard to say that these anomalies presage a large earthquake occurrence once they appear. Therefore, the observed anomalies before shocks regarded as possible precursors can be deemed as possible ones only. The time-space distributions of these possible precursors as a whole are different for different earthquakes, but there still exist some common characteristics as shown in Table 2. 2) Because of the complicated continental crustal structures, the temporal and spatial distributions of the continental seismicity in China are rather complex, but there are still some regularities, and some unique dynamic patterns featured with block-like, stripe- like, and diversified distributions of earthquakes (see Table 3). In addition to the above basic understandings, there are still many problems encountered in the earthquake prediction research in the past 18 years. These key difficulties for earthquake prediction are as follows: 2.1 Non-uniqueness of the relation between the anomalous variations and earthquake precursors The variations of the observed values are due to various factors as given in Fig. 1. Decisive anomalies are by no means synonymous with earthquake precursors. Very often no large earthquake occurs after anomalies take place. In fact, the so-called preseismic precursory anomalies may include variations due to other factors. Therefore, it is important for earthquake prediction research to clarify the factors in the observational variations, and the roles played by various factors, and to identify the nature of the observational variations. There are some available studies about these aspects, but the knowl- edge is still very primitive and qualitative. Especially, there is no effective quanti-
Load more

Recommended publications
  • The 2008 Wenchuan Earthquake: Risk Management Lessons and Implications Ic Acknowledgements
    The 2008 Wenchuan Earthquake: Risk Management Lessons and Implications Ic ACKNOWLEDGEMENTS Authors Emily Paterson Domenico del Re Zifa Wang Editor Shelly Ericksen Graphic Designer Yaping Xie Contributors Joseph Sun, Pacific Gas and Electric Company Navin Peiris Robert Muir-Wood Image Sources Earthquake Engineering Field Investigation Team (EEFIT) Institute of Engineering Mechanics (IEM) Massachusetts Institute of Technology (MIT) National Aeronautics and Space Administration (NASA) National Space Organization (NSO) References Burchfiel, B.C., Chen, Z., Liu, Y. Royden, L.H., “Tectonics of the Longmen Shan and Adjacent Regoins, Central China,” International Geological Review, 37(8), edited by W.G. Ernst, B.J. Skinner, L.A. Taylor (1995). BusinessWeek,”China Quake Batters Energy Industry,” http://www.businessweek.com/globalbiz/content/may2008/ gb20080519_901796.htm, accessed September 2008. Densmore A.L., Ellis, M.A., Li, Y., Zhou, R., Hancock, G.S., and Richardson, N., “Active Tectonics of the Beichuan and Pengguan Faults at the Eastern Margin of the Tibetan Plateau,” Tectonics, 26, TC4005, doi:10.1029/2006TC001987 (2007). Embassy of the People’s Republic of China in the United States of America, “Quake Lakes Under Control, Situation Grim,” http://www.china-embassy.org/eng/gyzg/t458627.htm, accessed September 2008. Energy Bulletin, “China’s Renewable Energy Plans: Shaken, Not Stirred,” http://www.energybulletin.net/node/45778, accessed September 2008. Global Terrorism Analysis, “Energy Implications of the 2008 Sichuan Earthquake,” http://www.jamestown.org/terrorism/news/ article.php?articleid=2374284, accessed September 2008. World Energy Outlook: http://www.worldenergyoutlook.org/, accessed September 2008. World Health Organization, “China, Sichuan Earthquake.” http://www.wpro.who.int/sites/eha/disasters/emergency_reports/ chn_earthquake_latest.htm, accessed September 2008.
    [Show full text]
  • Lessons Learnt from the 512 Wenchuan Earthquake: Perception of Seismic Risks
    Australian Earthquake Engineering Society Conference AEES 2008, Ballarat, Victoria. Special Session on 512 Wenchuan Earthquake Lessons Learnt from the 512 Wenchuan Earthquake: Perception of Seismic Risks Hing-Ho Tsang Research Fellow, Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China. Email: [email protected] Abstract On May 12, 2008, a devastating earthquake occurred in Sichuan Province of China depriving tens of thousands of lives and destroying homes of millions of people. In this article, the seismotectonic background and the seismicity of the regions are first introduced. The seismic hazard levels specified in the Chinese Code for Seismic Design of Buildings, GB 50011 – 2001, and issues concerning the perception of earthquake risks and the extensive damage to buildings in the affected regions are discussed. Keywords: Wenchuan Earthquake, Sichuan, China, seismic, hazard, risk, intensity 1. BRIEF BACKGROUND OF THE 512 WENCHUAN EARTHQUAKE At 06:28:01.42 UTC on May 12, 2008, a devastating earthquake occurred at the Wenchuan County in the Sichuan Province of China. On the moment magnitude scale, the earthquake was of Mw = 7.9 according to reports from the United States Geological Survey (USGS). On the surface wave magnitude scale, the earthquake was of Ms = 8.0 according to reports from the China Earthquake Administration (CEA). The epicentre of the earthquake was 80 km west-northwest of the provincial capital city of Chengdu (refer Figure 1(a)). The fault ruptured at a depth of about 19 km. There were over 200 aftershocks with magnitudes greater than 4.0 and 8 aftershocks with magnitude greater than 6.0 occurred in the area afterwards.
    [Show full text]
  • Characteristics of Foreshocks and Short Term Deformation in the Source Area of Major Earthquakes
    Characteristics of Foreshocks and Short Term Deformation in the Source Area of Major Earthquakes Peter Molnar Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge, Massachusetts 02139 USGS CONTRACT NO. 14-08-0001-17759 Supported by the EARTHQUAKE HAZARDS REDUCTION PROGRAM OPEN-FILE NO.81-287 U.S. Geological Survey OPEN FILE REPORT This report was prepared under contract to the U.S. Geological Survey and has not been reviewed for conformity with USGS editorial standards and stratigraphic nomenclature. Opinions and conclusions expressed herein do not necessarily represent those of the USGS. Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS. Appendix A A Study of the Haicheng Foreshock Sequence By Lucile Jones, Wang Biquan and Xu Shaoxie (English Translation of a Paper Published in Di Zhen Xue Bao (Journal of Seismology), 1980.) Abstract We have examined the locations and radiation patterns of the foreshocks to the 4 February 1978 Haicheng earthquake. Using four stations, the foreshocks were located relative to a master event. They occurred very close together, no more than 6 kilo­ meters apart. Nevertheless, there appear to have been too clusters of foreshock activity. The majority of events seem to have occurred in a cluster to the east of the master event along a NNE-SSW trend. Moreover, all eight foreshocks that we could locate and with a magnitude greater than 3.0 occurred in this group. The're also "appears to be a second cluster of foresfiocks located to the northwest of the first. Thus it seems possible that the majority of foreshocks did not occur on the rupture plane of the mainshock, which trends WNW, but on another plane nearly perpendicualr to the mainshock.
    [Show full text]
  • Shear-Wave Velocity–Based Probabilistic and Deterministic Assessment of Seismic Soil Liquefaction Potential
    Shear-Wave Velocity–Based Probabilistic and Deterministic Assessment of Seismic Soil Liquefaction Potential R. Kayen, M.ASCE ; R. E. S. Moss, M.ASCE ; E. M. Thompson, A.M.ASCE ; R. B. Seed, M.ASCE ; K. O. Cetin, M.ASCE ; A. Der Kiureghian, M.ASCE ; Y. Tanaka ; and K. Tokimatsu, M.ASCE Abstract: Shear-wave velocity (Vs) offers a means to determine the seismic resistance of soil to liquefaction by a fundamental soil property. This paper presents the results of an 11-year international project to gather new Vs site data and develop probabilistic correlations for seismic soil liquefaction occurrence. Toward that objective, shear-wave velocity test sites were identified, and measurements made for 301 new liquefaction field case histories in China, Japan, Taiwan, Greece, and the United States over a decade. The majority of these new case histories reoccupy those previously investigated by penetration testing. These new data are combined with previously published case histories to build a global catalog of 422 case histories of Vs liquefaction performance. Bayesian regression and structural reliability methods facilitate a probabilistic treatment of the Vs catalog for performance-based engineering applications. Where possible, uncertainties of the variables comprising both the seismic demand and the soil capacity were estimated and included in the analysis, resulting in greatly reduced overall model uncertainty relative to previous studies. The presented data set and probabilistic analysis also help resolve the ancillary issues of adjustment for soil fines content and magnitude scaling factors. Introduction correlating more directly with relative density, which has a strong effect on the cyclic behavior of saturated soil (Idriss and fi Of the several eld techniques routinely used to assess triggering of Boulanger 2008).
    [Show full text]
  • Active Tectonics and Intracontinental Earthquakes in China: the Kinematics and Geodynamics
    The Geological Society of America Special Paper 425 2007 Active tectonics and intracontinental earthquakes in China: The kinematics and geodynamics Mian Liu Youqing Yang Department of Geological Sciences, University of Missouri, Columbia, Missouri 65211, USA Zhengkang Shen State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China Shimin Wang Department of Geological Sciences, University of Missouri, Columbia, Missouri 65211, USA Min Wang Institute of Earthquake Science, China Earthquake Administration, Beijing 100036, China Yongge Wan School of Disaster Prevention Techniques, Yanjiao, Beijing 101601, China ABSTRACT China is a country of intense intracontinental seismicity. Most earthquakes in west- ern China occur within the diffuse Indo-Eurasian plate-boundary zone, which extends thousands of kilometers into Asia. Earthquakes in eastern China mainly occur within the North China block, which is part of the Archean Sino-Korean craton that has been thermally rejuvenated since late Mesozoic. Here, we summarize neotectonic and geo- detic results of crustal kinematics and explore their implications for geodynamics and seismicity using numerical modeling. Quaternary fault movements and global position- ing system (GPS) measurements indicate a strong infl uence of the Indo-Asian colli- sion on crustal motion in continental China. Using a spherical three-dimensional (3-D) fi nite-element model, we show that the effects of the collisional plate-boundary force are largely limited to western China, whereas gravitational spreading of the Tibetan Plateau has a broad impact on crustal deformation in much of Asia. The intense seis- micity in the North China block, and the lack of seismicity in the South China block, may be explained primarily by the tectonic boundary conditions that produce high devi- atoric stresses within the North China block but allow the South China block to move coherently as a rigid block.
    [Show full text]
  • Chinese Experience with Post-Natural-Disaster Reconstruction
    CHINESE EXPERIENCE WITH POST-NATURAL-DISASTER RECONSTRUCTION Ye Yaoxian* China Architectural Design and Research Group Abstract The paper begins with a discussion of the facts about natural disasters with emphasis on both floods and earthquakes that happened in China, and then shifting the focus from the lessons to be learnt from reconstruction to improvement of reconstruction strategies following a natural disaster. This includes policy development, decision making technology, and evaluation models and etc. The paper concludes with a summary of reconstruction experiences learned from the practices in past decades in China. Post-Natural-Disaster; reconstruction; China INTRODUCTION At the beginning of a millennium, it is appropriate but also necessary to look back upon the events happened in China and to see what lessons and prognoses concerning post-natural-disaster reconstruction can be derived from them for the future. The Government of People’s Republic of China, in response to various natural disasters that occurred in the country after its founding in 1949, particularly the 1976 Tangshan Earthquake which caused 242,000 deaths and the 1991 Anhui and Jiangsu flood which caused 5,000 deaths and 77.9 billion RMB of direct economic losses, noted the importance of significantly improved reconstruction strategies. Reconstruction following a natural disaster is a complicated problem concerning social, economical, cultural, environmental, psychological, and technological aspects. However, for developing countries or regions, it is a good opportunity to change its original economy development model and to push the urban and rural renewal forward. Therefore, improved strategies and reconstruction plans are the key to accelerate the reconstruction process and to improve human settlement environment.
    [Show full text]
  • Earthquake and Poverty with Chinese Characteristics Wenchuan Earthquake Affected Communities Ten Years After the Disaster
    UNIVERSITY OF OSLO Earthquake and poverty with Chinese characteristics Wenchuan earthquake affected communities ten years after the disaster Dragana Grulovic Asia and Middle East Studies/Chinese Society and Politics KIN4593 – Master’s Thesis in Chinese Society and Politics (30 credits) Department of Culture Studies and Oriental Languages Spring 2019 Earthquake and poverty with Chinese characteristics Wenchuan earthquake affected communities ten years after the disaster © Dragana Grulovic 2019 Earthquake and poverty with Chinese characteristics - Wenchuan earthquake affected communities ten years after the disaster Dragana Grulovic https://www.duo.uio.no Print: Webergs Print Abstract In May 2008, China was struck by a massive earthquake that killed closed to 70,000 people. Communities were torn to the ground, and the economic losses were enormous. Ten years have passed since the massive forces took place, and communities and lives have been rebuilt, with some preceding their pre-disaster economic levels. This study applies survey data to estimate the poverty rates in the Wenchuan earthquake affected communities ten years after the disaster. I find that in 2018, the poverty incidence was 3% in the overall area, as compared to 9% before the earthquake. Of the total of 198 sampled communities, 27 reported having no government- designated poor people. However, 23 communities have a poverty prevalence of 10% or higher. These communities have few characteristics in common in terms of demographic structure and access to public services. About half of the communities are located in government-designated poor counties, while the rest are not. Altogether, the poverty situation in the Wenchuan earthquake affected area reflects the complexity of poverty in China.
    [Show full text]
  • Pathways to Earthquake Resilience in China
    Report Pathways to earthquake resilience in China October 2015 Overseas Development Institute 203 Blackfriars Road London SE1 8NJ Tel. +44 (0) 20 7922 0300 Fax. +44 (0) 20 7922 0399 E-mail: [email protected] www.odi.org www.odi.org/facebook www.odi.org/twitter Readers are encouraged to reproduce material from ODI Reports for their own publications, as long as they are not being sold commercially. As copyright holder, ODI requests due acknowledgement and a copy of the publication. For online use, we ask readers to link to the original resource on the ODI website. The views presented in this paper are those of the author(s) and do not necessarily represent the views of ODI. © Overseas Development Institute 2015. This work is licensed under a Creative Commons Attribution-NonCommercial Licence (CC BY-NC 3.0). ISSN: 2052-7209 Cover photo: Photo by GDS, Children receiving the GDS disaster risk reduction kit, Shaanxi Province, China Contents Acknowledgements 9 About the authors 9 Glossary of terms 11 Acronyms 11 1. Introduction 13 John Young 2. Earthquake disaster risk reduction policies and programmes in China 16 Cui Ke, Timothy Sim and Lena Dominelli 3. Current knowledge on seismic hazards in Shaanxi Province 23 By Feng Xijie, Richard Walker and Philip England 4. Community-based approaches to disaster risk reduction in China 30 Lena Dominelli, Timothy Sim and Cui Ke 5. Case study: World Vision’s community disaster response plan in Ranjia village 42 William Weizhong Chen, Ning Li and Ling Zhang 6. Case study: Gender Development Solution’s disaster risk reduction in primary education 46 Zhao Bin 7.
    [Show full text]
  • Meeting the Sphere Standards: an Analysis of Earthquake Response in China
    Bo et al. China Earthquake Response and Sphere Standards Meeting the Sphere Standards: an analysis of earthquake response in China Tao Bo Bartel Van de Walle Earthquake Administration of Beijing Tilburg University, the Netherlands Municipality, China [email protected] [email protected] ABSTRACT As a country which frequently suffers from natural disasters, especially earthquakes, China has implemented its own disaster management system to respond to them. The Chinese government gained practical experiences on how to respond to severe earthquakes after the 2008 Wenchuan Earthquake and 2010 Yushu Earthquake. Although China has done a lot to improve its response operations, challenges remain. This paper analyses what these challenges are by using the Sphere Standard as a benchmark to measure the Chinese response operations. The Sphere project was launched in 1997 by Non-Government Organizations (NGOs), the International Federation of Red Cross and Red Crescent Societies. It framed a Humanitarian Charter and established the Minimum Standards for response which emphasize meeting the urgent survival needs of people in the affected regions, while asserting their basic human right to a life with dignity. Based on this analysis, suggestions are provided to improve China’s earthquake response operations. Keywords Earthquake response, Sphere Standards, China. INTRODUCTION In the past decade, humanity has suffered from a number of exceptionally devastating earthquakes: the Indian Ocean tsunami on December 26th 2004, the Wenchuan Earthquake on May 12th 2008, the Haiti Earthquake on January 13th 2010, the Yushu Earthquake on April 4th 2010, and the Japan Earthquake on March 11th 2011. According to the International Disaster Database provided by the Center for Research on the Epidemiology of Disaster (CRED), there is an increasing trend of natural disasters.
    [Show full text]
  • The Wenchuan, Sichuan Province, China, Earthquake of May 12, 2008
    EERI Special Earthquake Report — October 2008 Learning from Earthquakes The Wenchuan, Sichuan Province, China, Earthquake of May 12, 2008 A team sponsored by the Earth- Tectonic Setting school buildings that buried thou- quake Engineering Research Insti- sands of students and teachers. The M7.9 Wenchuan earthquake is tute (EERI) and the Geo-Engineer- the worst to strike China since the The earthquake originated on the ing Earthquake Reconnaissance M7.8 Tangshan event of July 1976 Longmenshan fault, a northeastern- (GEER) Association carried out a that claimed an estimated 242,000 striking thrust fault that ruptured for field investigation in conjunction lives. The Wenchuan earthquake af- almost 300 kilometers (see Figure 1). with Chinese colleagues from Aug- fected more than 100,000 square The fault is the result of conver- ust 3-11 to document effects of the miles and about 30 million people, gence of crust from the high Tibet- May 12 earthquake. The EERI- causing 69,226 deaths (as of August an Plateau to the west, against the GEER team was invited by Profes- 21, 2008) and injuring almost 375,000 strong and stable crust block under- sor Zifa Wang, Director of the In- people. Almost 1.5 million people had lying the Sichuan Basin and south- stitute of Engineering Mechanics- to be relocated (Xinhua, 2008). The west China to the east. On a contin- China Earthquake Administration earthquake also destroyed more than ental scale, the seismicity of central (IEM-CEA). Professor Junwu Dai 216,000 buildings in Sichuan Prov- and eastern Asia is a result of of the IEM-CEA accompanied the ince, including approximately 6,900 team during the field investigation.
    [Show full text]
  • Project Highlights
    Region: East Asia and Pacific Country: China PROJECT Focus Area: Resilient Reconstruction Resilient recovery and reconstruction policies, ex- HIGHLIGHTS ante design of institutional response mechanisms, etc. Supporting Resilient Post- earthquake Recovery in China Reconstruction from the Wenchuan Earthquake Background On May 12, 2008, an earthquake of magnitude 8.0 struck Southwestern China, centered in Wenchuan County of the Sichuan Province. As a result of the Wenchuan Earthquake and 30,000 significant aftershocks, more than 47 million people were affected; over 69,000 people died, 374,000 were injured and 18,000 went missing. General infrastructure was also overwhelmingly damaged, resulting in the destruction of 34,000km of highway, the damage of 1,263 reservoirs, the collapse of 7,444 schools and 11,028 hospitals and clinics and the destruction or significant deterioration of 5.5 million rural homes and 860,000 urban homes. The Sichuan and Gansu Provinces were the hardest hit, with direct economic losses estimated at US$112.2 billion and US$7.1 billion respectively. Highlights Reparation of 2.9 million rural houses Challenges and 1.5 million urban houses in China is among the top natural disaster areas in terms of mortality, total economic loss and eco- Gansu, Sichuan and Shaanxi Provinces. nomic loss as a proportion of gross domestic product (GDP). It is estimated that economic losses caused by disasters amount to between three and six percent of China’s total GDP. Reconstruction of 1.9 million rural houses and 290,000 million urban houses. The 2008 Wenchuan Earthquake was the costliest and most deadly earthquake in China since the 1976 Tangshan earthquake.
    [Show full text]
  • Air Earthquake Model for Mainland China
    In 1976, the M7.8 Tangshan AIR Earthquake Model earthquake killed 240,000 people and destroyed more for Mainland China than 90% of residential buildings in the area. In 2008, the M8.0 Wenchuan event became one of the costliest natural disasters in Chinese history, leveling nearly seven million buildings and damaging another 24 million. With rapid urbanization in seismically active regions and a burgeoning insurance market, companies operating in China need sophisticated tools to assess and manage their exposure to earthquake risk. AIR EARTHQUAKE MODEL FOR MAINLAND CHINA Collaborating with Chinese Scientists The AIR model incorporates the results of paleoseismological to Produce the Most Realistic Estimate research, in combination with historical seismicity, fault slip of Hazard rates, and data from China’s extensive GPS network, to The AIR Earthquake Model for Mainland China draws determine a regional strain rate field that provides information on the country’s long historical catalog, which includes not only on the rates and patterns of deformation, but also written records of earthquakes dating back to 780 B.C. on the style of faulting. Using this data, AIR seismologists Even so, historical data alone are not sufficient to provide implemented a probabilistic approach to modeling earthquake an accurate representation of the long-term seismic risk, in which the Longmen Shan fault figured prominently— hazard in China, particularly since some high-risk before the 2008 earthquake occurred. areas have not experienced significant earthquakes in recent history. Twenty-six seismic regions are defined to capture seismic activity across China. These regions, along with more Before the 2008 Wenchuan earthquake occurred, for than 300 source zones enclosing known active faults and example, the Longmen Shan fault zone that produced the gridded background seismicity, form the basis of the model’s temblor had not generated an earthquake exceeding M7.0 comprehensive catalog of simulated events—which contains during the last 500 years.
    [Show full text]