中国大陆及周边地区的水平应变场  

HORIZONTAL STRAIN FIELD IN THE CHINESE MAINLAND AND ITS SURROUNDING AREAS

作　　者：李延兴[1] 李智[1] 张静华[1] 黄珹[2] 朱文耀[2] 王敏[3] 郭良迁[1] 张中伏[1] 杨春花[1] 

机构地区：[1]中国地震局第一监测中心,天津300180 [2]中国科学院上海天文台,上海200030 [3]中国地震局分析预报中心,北京100036

出　　处：《地球物理学报》2004年第2期222-231,共10页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目 ( 4 0 1740 2 9) ;国家重点基础研究发展规划项目 (G19980 40 7)

摘　　要：推导并建立了块体的两种弹性运动方程 :块体的整体旋转与均匀应变方程和块体的整体旋转与线性应变方程 .应用统计学原理 ,使用西域、青藏和华北块体上的GPS站速度数据 ,对这两种弹性运动方程与刚体运动方程模拟块体站速度的无偏性和有效性进行了统计检验 .检验结果表明 ,块体的整体旋转与线性应变方程是描述块体运动的最优模型 .将中国大陆划分为 10个块体 ,应用块体的整体旋转与线性应变方程和块体上的GPS站速度估计了各个块体上的旋转与应变参数 ,按照 1°× 1°的间距计算了中国大陆及周边地区上 10 0 5个点的应变参数 ,分析了中国大陆及周边地区应变场的基本特征 .用本文方法得到的主压应变方向与地质学方法和测震学方法得到的主压应力轴方向具有很好的一致性 (华南块体除外 ) .In this paper, two kinds of equations of block elastic motion are established. One is the equation of rotation in the entire block and homogeneous strain, and the other is the equation of rotation in the entire block and linear strain. Using the velocities of GPS sites located in the Western Region, Qinghai-Xizang and North China blocks, these two kinds of elastic motion equations and the rigid motion equation are tested statistically for their unbiasedness and validity to simulate the site velocities of the blocks. The results indicate that the equation with rotation in the entire block and linear strain is the optimal model to describe the block motion. Dividing the Chinese mainland into 10 blocks, the rotation and strain parameters of each block are estimatedusing the equation with rotation in the entire block and linear strain and the velocities of GPS sites on the blocks. Then, the strain parameters of 1005 sites in the Chinese mainland and its surrounding areas are calculated with the spacing of 1°×1°, and the strain field in Chinese mainland and the surrounding areas is obtained. The basic characteristics of the strain field are also analyzed. The direction of the principal compressive strain obtained in the paper is well consistent with the principal compressive stress axes derived by the geological and seismological methods (except for South China block).

关 键 词：水平应变场 弹性运动方程 块体 统计学 GPS站速度数据 中国大陆 

分 类 号：P541[天文地球—构造地质学] P228.4[天文地球—地质学]