青藏高原东部地壳物质流变模型及汶川地震机理探讨  

Discussion of Crustal Flow Beneath the Eastern Tibetan Plateau and Mechanism of the Wenchuan Earthquake

作　　者：李冲[1,2] 李建成[1] 黄瑞金 谭理 

机构地区：[1]武汉大学测绘学院,湖北武汉430079 [2]四川省测绘产品质量监督检验站,四川成都610041

出　　处：《武汉大学学报（信息科学版）》2015年第6期810-815,共6页Geomatics and Information Science of Wuhan University

基　　金：国家自然科学基金资助项目(40637034;41210006;41274005)~~

摘　　要：利用GPS、大地电磁、P波层析成像等数据分析了青藏高原东部地壳运动情况和中下地壳物质流的分布及运动情况,提出了青藏高原东部地壳物质流变模型,认为在青藏高原东部存在两条巨大的、具有固定通道和边界的弱物质流,其他区域则有离散的、不均匀的弱物质流分布。巴颜喀拉块体内部的弱物质流在向东流至龙门山断裂带时,大部分弱物质沿断裂带向南北方向分流,小部分弱物质在断裂带附近沉积、上涌,造成通道堵塞,最终引发了汶川地震。The crustal deformation of eastern Tibetan Plateau using GPS is analysed. Then, the distribution and movement of viscous flows in the mid-lower crust of eastern Tibetan is discussed in terms of MT data and seismic tomography. A new viscous flows model is put forward, showing that there are two large-scale crustal flow channels and many unevenly distributed viscous flows in eastern Tibetan Plateau. Most viscous flows in the Bayan Har block may turn to south or north along the Longmen Mountain fault when meeting the fault, while limited viscous flows are depositing and upwelling nearby the Longmen Mountain fault, which has caused channel blockage, eventually triggeing the Wenchuan earthquake.

关 键 词：青藏高原 地壳流变 地震层析成像 汶川地震 

分 类 号：P227.1[天文地球—大地测量学与测量工程]