关键词: 昆仑山口西M_S8.1地震, 同震位移, 同震应力, 数值模拟

Abstract: The 14 November 2001 M_S 8.1 Kunlun earthquake at northern Tibet is the largest earthquake that occurred in the Chinese continent since 1950.We apply a three-dimensional(3-D)finite element numerical procedure to model the coseismic displacement and stress fields caused by the earthquake dislocations,which are constrained by field investigations.We then further investigate the stress interaction between the M_S 8.1 earthquake and the intensive aftershocks.Our primary calculation shows that the coseismic displacement field is centralized around the east Kunlun Fault zone.And the attenuation of coseismic displacements on the south side of Kunlun Fault zone is larger than that on the north side.The calculated coseismic stress field also indicates that the calculated maximal shear stress field is centralized around the east Kunlun Fault zone,and the directions of the coseismic maximal principal stress are contrary to that of the background crustal stress filed of Tibet Plateau.It indicates that the earthquake relaxes the crustal stress state in Tibet Plateau.Finally,we study the stress interaction between the M_S 8.1 earthquake and its intensive aftershocks.The calculated Coulomb stress changes of the M_S8.1 great earthquake are in favor of triggering 3 aftershocks.

Key words: Kunlun Shan M_S8.1 earthquake, coseismic displacement, coseismic stress, numerical simulation