Dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake
Haiming Zhang1, Xiaofei Chen2
1 College of Earth Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100049, China 2 School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
Dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake
Haiming Zhang1, Xiaofei Chen2
1 College of Earth Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100049, China 2 School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China
摘要In this study, we preliminarily investigated the dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake by using an extended boundary integral equation method, in which the effect of ground surface can be exactly included. Parameters for numerical modeling were carefully assigned based on previous studies. Numerical results indicated that, although many simplifications are assumed, such as the fault plane is planar and all heterogeneities are neglected, distribution of slip is still consistent roughly with the results of kinematic inversion, implying that for earthquakes in which ruptures run up directly to the ground surface, the dynamic processes are controlled by geometry of the fault to a great extent. By taking the common feature inferred by various kinematic inversion studies as a restriction, we found that the critical slip-weakening distance Dc should locate in a narrow region [60 cm, 70 cm], and supershear rupture might occur during this earthquake, if the initial shear stress before the mainshock is close to the local shear strength.
Abstract:In this study, we preliminarily investigated the dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake by using an extended boundary integral equation method, in which the effect of ground surface can be exactly included. Parameters for numerical modeling were carefully assigned based on previous studies. Numerical results indicated that, although many simplifications are assumed, such as the fault plane is planar and all heterogeneities are neglected, distribution of slip is still consistent roughly with the results of kinematic inversion, implying that for earthquakes in which ruptures run up directly to the ground surface, the dynamic processes are controlled by geometry of the fault to a great extent. By taking the common feature inferred by various kinematic inversion studies as a restriction, we found that the critical slip-weakening distance Dc should locate in a narrow region [60 cm, 70 cm], and supershear rupture might occur during this earthquake, if the initial shear stress before the mainshock is close to the local shear strength.
基金资助:the National Natural Science Foundation of China under grant Nos. 40504004 and 40521002, and partially by National Basic Research Program of China under grant No.2004CB418404
通讯作者:
Haiming Zhang
E-mail: zhanghm@gucas.ac.cn
引用本文:
Haiming Zhang, Xiaofei Chen. Dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake[J]. 《地震学报》英文版, 2009, 22(1): 3-12.
Haiming Zhang, Xiaofei Chen. Dynamic rupture process of the 1999 Chi-Chi, Taiwan, earthquake. Earthquake Science, 2009, 22(1): 3-12.