Fault plane parameters of Sanhe-Pinggu M8 earthquake in 1679 determined using present-day small earthquakes  

作　　者：Xiaoshan Wang Xiangdong Feng Xiwei Xu Guiling Diao Yongge Wan Libin Wang Guangqing Ma 

机构地区：[1]Institute of Geophysics, China Earthquake Administration [2]Earthquake Administration of Hebei Province [3]Institute of Geology, China Earthquake Administration [4]Institute of Disaster Prevention

出　　处：《Earthquake Science》2014年第6期607-614,共8页地震学报（英文版）

基　　金：jointly supported by the National Natural Science Foundation of China(Nos.91214201 and 41074072);Research Foundation of Science and Technology Plan Project in Hebei Province(12276903D)

摘　　要：The great Sanhe-Pinggu M8 earthquake occurred in 1679 was the largest surface rupture event recorded in history in the northern part of North China plain. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We relocated those earthquakes with the double-difference method. Based on the assumption that clustered small earthquakes often occur in the vicinity of fault plane of large earthquake, and referring to the morphology of the long axis of the isoseismal line obtained by the predecessors, we selected a strip-shaped zone from the relocated earthquake catalog in the period from 1980 to 2009 to invert fault plane parameters of this earthquake. The inversion results are as follows： the strike is 38.23°, the dip angle is 82.54°, the slip angle is -156.08°, the fault length is about 80 km, the lower-boundary depth is about 23 km and the buried depth of upper boundary is about 3 kin. This shows that the seismogenic fault is a NNE-trending normal dip-slip fault, southeast wall downward and northwest wall uplift, with the right-lateral strike-slip component. Moreover, the surface rupture zone, intensity distribution of the earth-quake and seismic-wave velocity profile in the focal area all verified our study result.The great Sanhe-Pinggu M8 earthquake occurred in 1679 was the largest surface rupture event recorded in history in the northern part of North China plain. This study determines the fault geometry of this earthquake by inverting seismological data of present-day moderate-small earthquakes in the focal area. We relocated those earthquakes with the double-difference method. Based on the assumption that clustered small earthquakes often occur in the vicinity of fault plane of large earthquake, and referring to the morphology of the long axis of the isoseismal line obtained by the predecessors, we selected a strip-shaped zone from the relocated earthquake catalog in the period from 1980 to 2009 to invert fault plane parameters of this earthquake. The inversion results are as follows： the strike is 38.23°, the dip angle is 82.54°, the slip angle is -156.08°, the fault length is about 80 km, the lower-boundary depth is about 23 km and the buried depth of upper boundary is about 3 kin. This shows that the seismogenic fault is a NNE-trending normal dip-slip fault, southeast wall downward and northwest wall uplift, with the right-lateral strike-slip component. Moreover, the surface rupture zone, intensity distribution of the earth-quake and seismic-wave velocity profile in the focal area all verified our study result.

关 键 词：Sanhe-Pinggu M8 earthquake Present-daymoderate-small earthquakes - Double-differenceearthquake location - Tectonic stress field Fault planeparameter 

分 类 号：P315[天文地球—地震学]