Numerical Green’s function method:Application to quantifying ground motion variations of M7 earthquakes  

作　　者：Haijiang Wang Heiner Igel Frantisek Gallovic 

机构地区：[1]School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China [2]Department of Earth and Environmental Studies, Section Geophysics, Ludwig-Maximilians-University, Miinchen 80333, Germany [3]Mengcheng National Geophysical Observatory, School of Earth and Space Sciences, University of Science and Technology of China, Mengcheng 233527, China

出　　处：《Earthquake Science》2010年第3期205-214,共10页地震学报（英文版）

基　　金：funding from the International Quality Network:Georisk (Ger-man Academic Exchange Service),and the Elite Gradu-ate College THESIS (Bavarian Government);support from the European Hu-man Resources Mobility Program (Research Training Network SPICE)

摘　　要：The concept of ＂numerical Green’s functions＂ （NGF or Green’s function database） is developed. The basic idea is： a large seismic fault is divided into subfaults of appropriate size, for which synthetic Green’s functions at the surface （NGF） are calculated and stored. Consequently, ground motions from arbitrary kinematic sources can be simulated, rapidly, for the whole fault or parts of it by superposition. The target fault is a simplified, vertical model of the Newport-Inglewood fault in the Los Angeles basin. This approach and its functionality are illustrated by investigating the variations of ground motions （e.g. peak ground velocity and synthetic seismograms） due to the source complexity. The source complexities are considered with two respects： hypocenter location and slip history. The results show a complex behavior, with dependence of absolute peak ground velocity and their variation on source process directionality, hypocenter location, local structure, and static slip asperity location. We concluded that combining effect due to 3-D structure and finite-source is necessary to quan- tify ground motion characteristics and their variations. Our results will facilitate the earthquake hazard assessment projects.The concept of ＂numerical Green’s functions＂ （NGF or Green’s function database） is developed. The basic idea is： a large seismic fault is divided into subfaults of appropriate size, for which synthetic Green’s functions at the surface （NGF） are calculated and stored. Consequently, ground motions from arbitrary kinematic sources can be simulated, rapidly, for the whole fault or parts of it by superposition. The target fault is a simplified, vertical model of the Newport-Inglewood fault in the Los Angeles basin. This approach and its functionality are illustrated by investigating the variations of ground motions （e.g. peak ground velocity and synthetic seismograms） due to the source complexity. The source complexities are considered with two respects： hypocenter location and slip history. The results show a complex behavior, with dependence of absolute peak ground velocity and their variation on source process directionality, hypocenter location, local structure, and static slip asperity location. We concluded that combining effect due to 3-D structure and finite-source is necessary to quan- tify ground motion characteristics and their variations. Our results will facilitate the earthquake hazard assessment projects.

关 键 词：numerical Green＇s function ground motion variation hypocenter location static displacement distribution 

分 类 号：P315.01[天文地球—地震学]