川滇地区地壳水平运动与变形场的演化特征及其机制讨论  

Discussion about the Evolvement Characteristics and the Mechanism of the Crustal Horizontal Movement and Deformation Field in Sichuan-Yunnan Area

作　　者：杨国华[1] 韩月萍[1] 杨博[1] 

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《地震研究》2009年第3期275-282,共8页Journal of Seismological Research

基　　金："十一五"国家科技支撑课题(2006BAC01B03-01-01);中国地震局"强化华北地区强震监视跟踪项目"联合资助

摘　　要：通过对川滇地区近年来的GPS资料的处理和分析,确定以1999～2004年的3期资料为基础获取相对于区域无旋转基准的背景性运动场,并以此为基本约束,利用2005年和2007年的资料分别获取不同时段的偏离位移场。综合运动场与位移场结果并借助连续应变模型分析了水平形变场的主要特征,得到如下结果:川滇菱形块体的东边界带是该区的主要形变带,菱形块体及以西的地域表现为明显的顺时针旋转形变运动。2004年12月26日印尼苏门答腊巨震的同震影响波及到川滇地区,导致该区中、南部产生SSW向偏离位移,北部产生NW向偏离位移,对汶川地震的发生可能有正影响作用。Sichuan-Yunnan is the most prominent area in China for its ctrustal movement and deformation, so it be- comes an indispensable aspect to realize its basic characteristic and dynamic change among a lot of research sub- jects in geology. Through processing and analyzing almost all the GPS data in this area in recent years, we obtain the background movement field relative to the data with no rotation based on 3 time period data from 1999 to 2004, and make it as the basic restriction to get respectively the departure displacement field of different period by using the data in 2005 and in 2007. Integrating the data in movement field and displacement field and using continuous strain model, we analyze the main characteristics of horizontal deformation field, and acquire results as follows： The main deformation region in Sichuan-Yunnan area is located in the east boundary of Sichuan- Yunnan Rhombic Block. The Block and the west region to it obviously revolved clockwise. The Indonesia earth- quake on 26th December, 2004 coseismicly affected Sichuan-Yunnan Area, and resulted in a departure displace- ment in SSW direction in the southern part and in NW direction in the northern part of Sichuan-Yunnan area. The Indonesia earthquake probably touched off the Wenchuan earthquake.

关 键 词：川滇地区 地壳水平活动 印尼地震 演化特征 机制分析 

分 类 号：P542.1[天文地球—构造地质学]