利用GPS观测资料分析山西地堑系现今地壳构造活动特征  

Present Tectonic Motion Feature of Shanxi Graben Based on the GPS Monitoring Data

作　　者：瞿伟[1,3] 张勤[1,3] 王庆良[2] 李振洪[3] 

机构地区：[1]长安大学地质工程与测绘学院,西安市710054 [2]中国地震局第二监测中心,西安市710054 [3]格拉斯哥大学地理与地球科学学院,英国格拉斯哥,G128QQ

出　　处：《武汉大学学报（信息科学版）》2012年第2期195-198,246,共5页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金重点资助项目(40534021);国家自然科学基金资助项目(40902081,40802075);国土资源大调查资助项目(1212010914015)

摘　　要：基于中国地壳运动观测网络1999～2007年的GPS复测资料,建立起整体无净旋转基准,分析了山西地堑系内部地壳运动的细节特征,并利用图形单元法分析了其应变场的分布特征,深入剖析了地壳变形的动力学机制,得出山西地堑系现今构造应变场以NW-SE向拉张应变为主,与区域现代震源机制解及长期构造变形背景相一致;临汾、大同盆地是地堑内剪切应变高值区,现今地壳活动强烈。解释了地堑系内形变异常区的成因,由此揭示出连接临汾与太原盆地的构造隆起带两端的现今地壳活动十分强烈,并同时兼有拉张破裂趋势这一重要的构造事件。In order to visualize the detail motion among stations within the Shanxi graben,we build the No-Net-Rotation based on the GPS repeat observations from 1999 to 2007 of the crustal motion observation network in China.Then the spatial distribution feature of strain fields are analyzed by graphic element method,and the dynamic mechanism of crustal deformation is also deeply analyzed.The results show that present tectonic strain fields of Shanxi graben present tensile strain with NNW-SSE direction,which has good consistency with the earthquake focal mechanisms and regional long-term tectonic deformation background.And the present crustal movement of Linfen and Datong basin is strong,meanwhile,the Linfen and Datong basin is also the areas with high shear strain.In the end the reason of exceptive deformation area is discussed.Then we put forward a significant tectonic event that the crustal activities of tectonic uplift between the Linfen and Taiyuan basin is fierce,and the tectonic uplift is now undergo intense tension rupture.

关 键 词：山西地堑 GPS 应变特征 动力学机制 构造事件 

分 类 号：P227[天文地球—大地测量学与测量工程] P228.42[天文地球—测绘科学与技术]