中国大陆GPS结果的构造及动力学意义有限元分析  

TECTONIC AND DYNAMIC IMPLICATION OF GPS OBSERVATIONS IN CHINA CONTINENT FROM FINITE ELEMENT ANALYSIS

作　　者：刘峡[1] 傅容珊[1] 郑勇[1] 黄建平[1] 张祖胜[2] 孙东平[2] 

机构地区：[1]中国科学技术大学地球和空间科学学院,合肥230026 [2]中国地震局第一监测中心,天津300180

出　　处：《大地测量与地球动力学》2007年第3期6-11,共6页Journal of Geodesy and Geodynamics

基　　金：中国科学院创新项目(KZCX3-SW-131);国家自然科学基金(40274033);科技部2002年度社会公益研究专项(2002DIA1000)

摘　　要：通过建立中国大陆构造运动三维有限元模型,计算了在印度板块推挤驱动和地幔对流产生的岩石层底部拖曳力驱动下的中国大陆形变,以及与GPS观测结果之间的差异速度场分布。计算结果表明:多驱动力和中时间尺度(10万年)的中国大陆岩石层运动格局与短时间尺度(10年)GPS观测显示的格局总体趋势一致;而差异速度场的特征表现为:青藏块体内部出现向外的扩张趋势,其北部的阿尔金断裂带显示出强烈的左旋走滑差异运动,塔里木地块以及西南地区以缅甸弧为中心差异速度场呈现整体顺时针转动,华北北部张渤地震带显示出较强的差异运动。上述结果表明:1)中国大陆现代构造运动的格局源于印度大陆推挤为主的驱动力,同时还包括深部物质运移对岩石层底部的拖曳作用;2)一些大型破裂系统现今构造活动比较活跃,强烈影响了现阶段中国大陆表层水平运动的分布。Two 3D finite element models of China continent are created and the continental deformation under the India-Eurasia collision and basal traction resulting from mantle convection is calculated. And the differential velocity field between the theoretical result and the GPS observation is calculated. The theoretical simulations in mid- dle time scale （0.1 ma） are consistent with that of GPS observation which focuses on the surface movement in the short time scale of 10 years. In the differential velocity field, Tibetan plateau assumes a strong outside extrusive trend, while Ahyn Tagh fault which is located in the north margin of Tibetan plateau shows remarkable left-lateral differential movement, Tarim basin and southwest region of China around Burma arc indicate uniform clock-wise rotation, and Zhang-bo fault system in North China assumes left-lateral differential movement. Such character could be generalized that multiple diving forces including India-Eurasia collision and basal traction resulting from mantel convection control constructional movement of China continent, at the same time, large fault systems also influence the movement pattern.

关 键 词：GPS 三维有限元 构造运动 差异速度场 驱动力 

分 类 号：P227[天文地球—大地测量学与测量工程] P542.4[天文地球—测绘科学与技术]