天津地区的水平应变场特征  

CHARACTERISTICS OF HORIZONTAL STRAIN FIELD IN TIANJIN

作　　者：郭良迁[1] 薄万举[1] 胡新康[1] 

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《大地测量与地球动力学》2010年第5期8-14,共7页Journal of Geodesy and Geodynamics

基　　金：天津市应用基础研究课题(08JCZDJC18900)

摘　　要：根据1995—1999年、1999—2004年和2004—2009年天津地区GPS站点观测资料,分不同地块计算了主应变率和断裂带的差异应变率。在此基础上研究了天津地区应变场和断层应变。结果显示,天津地区整体由主应变方向揭示的主压应力方向,前两个时段为北西向,后一个时段为北东东向;次级小块体的主压应力方向变化较大;块体边界断裂有的成为应变梯度带,有的不明显;断裂带的差异应变率在不同时段,差别显著;地震活动与高应变带、应变梯度带、断裂带的差异应变率较大的地段有一定的关系。On the basis of the observations from Tianjin GPS site during 1995 - 1999, 1999 - 2004 and 2004 - 2009, the principal strain rate and the difference of strain rate of fault zone were calculated for different blocks. The results show that the principal compressive stress direction of the overall Tianjin was the NW direction in the first two periods, the NEE direction in the last period, which is revealed by the direction of principal strain. The principal compressive stress direction of secondary small block changes considerably. Some of faults in block boundaries have become strain gradient zone, while the others are not obvious. The differences between the differ- ential strain rate of fault zone are significant in different periods. Seismic activity has a certain relationship with high strain zone, strain gradient zone, and the zone with higher differential strain rate of fault zone.

关 键 词：GPS 主应变率 面应变率 最大剪应变率 差异应变率 

分 类 号：P315.72[天文地球—地震学]