ON INFLUENCES OF EARTH STRATIFICATION AND GRAVITATION ON CO-SEISMIC DEFORMATION
Yuan Xudong1,2), Wang Hansheng1), Ke Xiaoping1) and Wang Zhiyong1,2) 1)Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, CAS, Wuhan 430077 2)Graduate University of Chinese Academy of Sciences, Beijing 100049
The co-seismic vertical and horizontal deformations for two earthquakes(Tangshan M7.8 earthquake in 1976,Jiashi M6.8 earthquake in 2003) in China are calculated by use of the two softwares for co-seismic and post-seismic deformation.The computations are implemented under the cases of taking into account/neglecting the gravitation with elastic homogeneous half-space/elastic layered half-space earth model respectively. The results show that the influences of earth’s stratification and gravity on the co-seismic deformation greatly exceed the resolution of modern observation techniques. It indicates the influences of earth’s stratification and gravity cann’t be ignored in analyzing the similar earthquakes with the Okada’s model.