Possible　dynamics　of　normal－fault　earthquakes　in　the　upper　crust　of　the　south　part　of　the　Qinghai－Xizang　Plateau  

作　　者：张东宁 许忠淮 

出　　处：《Acta Seismologica Sinica(English Edition)》1995年第2期233-239,共7页

摘　　要：A numerical model for generating normal fault earthquakes in the Qinghai-Xizang Plateau′S upper crust is constructed with 3-D elasto-viscous finite element method. Based on the numerical simulation calculation,some conclusions were got:If the effective viscosity of the upper crust material is less than that of lower strata of the crust in the Qinghai-Xizang Plateau, even under the strong push of India continent,the stress state of the upper crust can still be extensional in south part of the Qinghai-Xizang Plateau.Numerical simulations show that the stress state changes with the depth of the lithosphere,from extensional stress state in upper crust to compressive in the lower part.Extensional stress state may exist mainly in the upper crust of the south part of the Qinghai-Xizang Plateau.A numerical model for generating normal fault earthquakes in the Qinghai-Xizang Plateau′S upper crust is constructed with 3-D elasto-viscous finite element method. Based on the numerical simulation calculation,some conclusions were got:If the effective viscosity of the upper crust material is less than that of lower strata of the crust in the Qinghai-Xizang Plateau, even under the strong push of India continent,the stress state of the upper crust can still be extensional in south part of the Qinghai-Xizang Plateau.Numerical simulations show that the stress state changes with the depth of the lithosphere,from extensional stress state in upper crust to compressive in the lower part.Extensional stress state may exist mainly in the upper crust of the south part of the Qinghai-Xizang Plateau.

关 键 词：Qinghai-Xizang subplate normal fault seismic activity finite element effective viscosity 

分 类 号：P315[天文地球—地震学]