On 5th November 2003,the central part of Tanzania (Dodoma),located within the eastern branch of the East African Rift System was struck by an M_s 5.5 earthquake that destroyed a school,a dispensary near its epicenter ...On 5th November 2003,the central part of Tanzania (Dodoma),located within the eastern branch of the East African Rift System was struck by an M_s 5.5 earthquake that destroyed a school,a dispensary near its epicenter and caused a huge crack on the Parliamentary building of Tanzania.This was one of the relatively large earthquakes that affected the area after the M_s 6.1 that occurred north of the Dodoma within the Manyara-Dodoma rift segment in May 7,展开更多
Through the statistical analysis of earthquake distribution along 51 strike-sli p active fault segments on the Chinese continent, we found that strong earthquak e distribution along the seismogenic fault segments is i...Through the statistical analysis of earthquake distribution along 51 strike-sli p active fault segments on the Chinese continent, we found that strong earthquak e distribution along the seismogenic fault segments is inhomogeneous and the dis tribution probability density p(K) can be stated as p(K)=1.1206e -3.947K in which K=S/(L/2), S refers to the distance from earthquake epicenter to the center of a fault segment, L is the length of the fault segment. The above model can be utilized to modify the probability density of earthquake occurrence of t he maximum magnitude interval in a potential earthquake source. Nevertheless, it is only suitable for those potential earthquake sources delineated along a sing le seismogenic fault. This inhomogeneous model has certain effects on seismic risk assessment, especia ll y for those potential earthquake sources with higher earthquake reoccurrence rat es of the maximum magnitude interval. In general, higher reoccurrence rate of th e maximum magnitude interval and lower exceeding probability level may bring lar ger difference of the results in seismic risk analysis by adopting the inhomogen eous model, the PGA values increase inner the potential earthquake source, but r educe near the vicinity and out of the potential earthquake source. Taking the T angyin potential earthquake source as an example, with exceeding probability of 10% and 2% in 50 years, the difference of the PGA values between inhomogeneous m odel and homogenous models can reach 12%.展开更多
This paper reviewed the main target,functions,tool( Open Quake software) and research achievements of the Global Earthquake Model( GEM) Foundation,and made a simple prospect on the development and application of proje...This paper reviewed the main target,functions,tool( Open Quake software) and research achievements of the Global Earthquake Model( GEM) Foundation,and made a simple prospect on the development and application of projects of GEM in the future. Learning from GEM and Open Quake is helpful to improve the seismic hazard model of China and enhance the scientificity of the seismic hazard assessment for metropolitans and major engineering facilities near major seismogenic structures.展开更多
Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic ear...Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic earthquake prediction is limited by numerous difficulties. Identifying the temporal and spatial statistical characteristics of earthquake occurrences and constructing earthquake risk statistical prediction models have become significant;particularly for evaluating earthquake risks and addressing seismic planning requirements such as the design of cities and lifeline projects based on the obtained insight. Since the 21 st century, the occurrence of a series of strong earthquakes represented by the Wenchuan M8 earthquake in 2008 in certain low-risk prediction areas has caused seismologists to reflect on traditional seismic hazard assessment globally. This article briefly reviews the development of statistical seismology, emphatically analyzes the research results and existing problems of statistical seismology in seismic hazard assessment, and discusses the direction of its development. The analysis shows that the seismic hazard assessment based on modern earthquake catalogues in most regions should be effective. Particularly, the application of seismic hazard assessment based on ETAS(epidemic type aftershock sequence)should be the easiest and most effective method for the compilation of seismic hazard maps in large urban agglomeration areas and low seismic hazard areas with thick sedimentary zones.展开更多
This study presents a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China.The model comprises a township-level residential building exposure model,a vulnerability model derived from the Chin...This study presents a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China.The model comprises a township-level residential building exposure model,a vulnerability model derived from the Chinese building taxonomy,and a regional probabilistic seismic hazard model.The three components are integrated by a stochastic event-based method of the OpenQuake engine to assess the regional seismic risk in terms of average annual loss and exceedance probability curve at the city,province,and regional levels.The novelty and uniqueness of this study are that a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China is developed by considering the impact of site conditions and epistemic uncertainty from the seismic hazard model.展开更多
文摘On 5th November 2003,the central part of Tanzania (Dodoma),located within the eastern branch of the East African Rift System was struck by an M_s 5.5 earthquake that destroyed a school,a dispensary near its epicenter and caused a huge crack on the Parliamentary building of Tanzania.This was one of the relatively large earthquakes that affected the area after the M_s 6.1 that occurred north of the Dodoma within the Manyara-Dodoma rift segment in May 7,
文摘Through the statistical analysis of earthquake distribution along 51 strike-sli p active fault segments on the Chinese continent, we found that strong earthquak e distribution along the seismogenic fault segments is inhomogeneous and the dis tribution probability density p(K) can be stated as p(K)=1.1206e -3.947K in which K=S/(L/2), S refers to the distance from earthquake epicenter to the center of a fault segment, L is the length of the fault segment. The above model can be utilized to modify the probability density of earthquake occurrence of t he maximum magnitude interval in a potential earthquake source. Nevertheless, it is only suitable for those potential earthquake sources delineated along a sing le seismogenic fault. This inhomogeneous model has certain effects on seismic risk assessment, especia ll y for those potential earthquake sources with higher earthquake reoccurrence rat es of the maximum magnitude interval. In general, higher reoccurrence rate of th e maximum magnitude interval and lower exceeding probability level may bring lar ger difference of the results in seismic risk analysis by adopting the inhomogen eous model, the PGA values increase inner the potential earthquake source, but r educe near the vicinity and out of the potential earthquake source. Taking the T angyin potential earthquake source as an example, with exceeding probability of 10% and 2% in 50 years, the difference of the PGA values between inhomogeneous m odel and homogenous models can reach 12%.
基金sponsored by the Specific Fund of Fundamental Research,Institute of Geophysics,China Earthquake Administration (DQJB16B19)
文摘This paper reviewed the main target,functions,tool( Open Quake software) and research achievements of the Global Earthquake Model( GEM) Foundation,and made a simple prospect on the development and application of projects of GEM in the future. Learning from GEM and Open Quake is helpful to improve the seismic hazard model of China and enhance the scientificity of the seismic hazard assessment for metropolitans and major engineering facilities near major seismogenic structures.
基金This work was supported by the National Natural Science Foundation of China(Grant No.U2039204)the National Key R&D Program of China(Grant No.2018YFC1504203).
文摘Earthquakes are one of the natural disasters that pose a major threat to human lives and property. Earthquake prediction propels the construction and development of modern seismology;however, current deterministic earthquake prediction is limited by numerous difficulties. Identifying the temporal and spatial statistical characteristics of earthquake occurrences and constructing earthquake risk statistical prediction models have become significant;particularly for evaluating earthquake risks and addressing seismic planning requirements such as the design of cities and lifeline projects based on the obtained insight. Since the 21 st century, the occurrence of a series of strong earthquakes represented by the Wenchuan M8 earthquake in 2008 in certain low-risk prediction areas has caused seismologists to reflect on traditional seismic hazard assessment globally. This article briefly reviews the development of statistical seismology, emphatically analyzes the research results and existing problems of statistical seismology in seismic hazard assessment, and discusses the direction of its development. The analysis shows that the seismic hazard assessment based on modern earthquake catalogues in most regions should be effective. Particularly, the application of seismic hazard assessment based on ETAS(epidemic type aftershock sequence)should be the easiest and most effective method for the compilation of seismic hazard maps in large urban agglomeration areas and low seismic hazard areas with thick sedimentary zones.
基金The financial support received from the Scientific Research Fund of Institute of Engineering Mechanics,China Earthquake Administration(Grant No.2023B09)National Key R&D Program of China(2022YFC3004404)Shenzhen Science and Technology Program(ZDSYS20210929115800001)are gratefully acknowledged。
文摘This study presents a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China.The model comprises a township-level residential building exposure model,a vulnerability model derived from the Chinese building taxonomy,and a regional probabilistic seismic hazard model.The three components are integrated by a stochastic event-based method of the OpenQuake engine to assess the regional seismic risk in terms of average annual loss and exceedance probability curve at the city,province,and regional levels.The novelty and uniqueness of this study are that a probabilistic seismic risk model for the Beijing-Tianjin-Hebei region in China is developed by considering the impact of site conditions and epistemic uncertainty from the seismic hazard model.
