利用GPS和震源机制解研究青藏块体东北部构造应力场方向变化特征  

STUDY ON THE DIRECTIONS OF TECTONIC STRESS FIELD IN NORTHEASTERN AREA OF QINGHAIXIZANG BLOCK BY USING GPS DATA AND FOCAL MECHANISM SOLUTIONS OF EARTHQUAKES

作　　者：郑申宝[1] 王双绪[2] 蒋锋云[2] 程宏宾[2] 王继英[2] 

机构地区：[1]中国科学技术大学地球物理与空间学院,安徽合肥230026 [2]中国地震局第二监测中心,陕西西安710054

出　　处：《高原地震》2007年第3期1-5,共5页Plateau Earthquake Research

基　　金："十一五"国家科技计划支撑项目(2006BAC01B02-02-03)

摘　　要：利用1970年以来至今青藏块体东北部大量的震源机制解,分时间统计其主压应力方位并求其归一化分布。根据P轴的优势分布方位,推测其主压应力方向。同时,借助有限元方法,利用GPS大地水平形变观测资料,把1999年以来青藏块体东北部大量的GPS资料经过解算,计算其最大主应变率场及最大剪切应变率场。将震源机制解P轴的主压应力方向和GPS计算的最大主应力方向进行对比,分析青藏块体东北部构造应力场随时空的变化特点及时空差异性,探讨震源机制解P轴的优势分布方位、GPS资料的最大主应力方向与地震孕育之间的关系。Using northeast Qinghai and Xizang block body massive focal mechanism solutions of earthquakes since 1970, it is counted the compression stress position and normal;Ted total direction of tectonic stress by years. According to the P axis superiority distribution position, the compression stress direction is extrapolated.At the same time, with the aid of the finite element method and the GPS earth horizontal deformation observed data, in northeast Qinghai and Xizang block body, the massive GPS material is calculated since 1999 after the solution, and calculated the maximum principal strain rate field and the great shearing strain rate field. To contrast between the compression stress direction of the P axis of focal mechanism solutions of earthquakes and the GPS calculational biggest principal stress direction, it is analyzed the structural stress field in northeast Qinghai and XiTang block with the changes of space and time characteristics and differences. And it is discussed the relations among the focal mechanism solutions of earthquakes, the P axis superiority distribution position, the GPS material biggest principal stress direction and earthquakes.

关 键 词：震源机制解 主压应力方向 GPS 水平形变 

分 类 号：P315.33[天文地球—地震学]