汶川Ms8．0地震后川滇地区地壳水平形变特征研究  

CRUSTAL DEFORMATION CHARACTERISTICS AFTER Ms8. 0 WENCHUAN EARTHQUAKE IN SICHUAN-YUNNAN REGION

作　　者：党学会[1,2] 乔学军[1] 赵斌[1] 吕健[1] 王恒信[2] 张昀龙 

机构地区：[1]中国地震局地震研究所地震大地测量重点实验室,武汉430071 [2]中国地震局第一豁测中心,天津300180 [3]中铁二十局第二工程有限公司,北京100000

出　　处：《大地测量与地球动力学》2013年第4期13-16,共4页Journal of Geodesy and Geodynamics

基　　金：中国地震局地震行业科研专项(201208009);国家自然科学基金(41274027,41274037)

摘　　要：利用"陆态网络"2009、2011年两期GPS观测数据,计算得到川滇地区296个测站的速度场。根据水平速度场,基于连续变形假说,运用三角形法给出了该地区的水平应变场分布图像。初步分析表明:1)川滇地区的地壳运动速度具有北强南弱、西强东弱、以菱形块体为主顺时针旋转的特征;2)主压应变轴和震源机制解的P轴方向的计算结果表明,在较长时间段内该地区地壳构造应力场是相对稳定的;3)主应变和最大剪应变率的高值区主要位于龙门山断裂带及其附近区域,此外鲜水河断裂带的南段和红河断裂带的西北段也表现出明显的最大剪应变率高值特性。The velocity field of the 296 stations in the Sichuan-Yunnan region has been obtained with the GPS observation data of the CMONOC from 2009 to 2011. Based on the continuous deformation hypothesis, we use the data of the horizontal velocity field to compute the distribution of horizontal strain field in this region by the triangle method. Preliminary analysis indicates that ： 1 ） In Sichuan-Yunnan region, the crustal movement of north and west is stronger than that of south and east. The Sichuan-Yunnan rhombic block is characterized by clockwise rotation. 2） The directions of the principal compressive strain axis and the P axis of the focal mechanism solution show that tectonic stress field in this region is relatively stable in a long term. 3 ） The high value areas of the principal strain and the maximum shear strain rate are in the Longmenshan fault zone and its surrounding region. In addition to the above areas, the significant high-value properties of the maximum shear strain rate can be seen in the south of the Xianshuihe fault zone and the northwest segment of the Red River fault zone.

关 键 词：川滇地区 应变率场 GPS 三角形法 地壳形变 

分 类 号：P315.72[天文地球—地震学]