【摘要】 2009年11月上海松江地震序列距佘山形变观测点约18 km,距查山形变台约32 km。地震前这两个定点的形变观测均出现不同程度的异常。结合形变资料和震源机制解分析结果发现,此次异常的应力方向与该区域的背景应力场方向基本一致,因此认为,观测到的形变异常很可能反映的是区域构造应力场的变化情况。更多还原

【Abstract】 The distances between Shanghai Songjiang seismic sequence in Novemeber,2009 and Sheshan deformation station,Chashan deformation station are about 18 km and 32 km respectively.The deformation observations appeared of different anomaly degree at these two stations before the earthquakes.The results combined the deformation data with focal mechanism solution show that the direction of the anomaly is consistent with the direction of background stress field of this area,so we think that the observed deformation anomalies are likely to reflect the changes in tectonic stress field.更多还原