三峡重庆地区形变场及构造应力场研究

摘要

首次利用三峡重庆地区GPS、钻孔应变及数字地震资料,综合研究该地区水平形变场及构造应力场.结果表明,各站点相对丰都龙河站运动速率在0～3 mm/a,呈现一定的右旋特征;整个区域表现为压性特征,区域主压应变方向为NW向及NE向;最大剪应变等值线在渝西南、渝东北及与渝东南分别出现高梯度带,与主要地震活动区域相对应.%Using GPS,borehole strain and digital seismic data,we study the horizontal deformation and tectonic stress fields in the Chongqing area.The results show that the inside of the Chongqing region presents relative motion of 0～3 mm/a and presents certain features of the dextral.The region as a whole performs as pressure characteristic.The predominant principal compressive strain direction of the local region is in a NWW direction,the direction of the tectonic stress field direction is consistent,the direction of the part of the region near the impact fracture appears to be a NNE direction,and the maximum shear strain contour line is southwest of Chongqing.Northeast and southeast Chongqing show a high gradient zone,and the gradient belt corresponds to the Chongqing area of the main area of seismic activity.