【作者】 唐文清；

【导师】 蔡英；

【作者基本信息】 西南交通大学 ， 道路与铁道工程， 2006， 博士

【摘要】 青藏高原东部及邻区为典型的大陆地壳变形区。长期的构造活动形成了一系列规模宏大的活动断裂，这些不同性质的断裂又将高原地壳切割成大小不同、形状各异的活动地块。活动地块和断裂构成了该区主要的构造框架。该区具有复杂、多变的地质构造，是研究地壳形变以及青藏高原形成、演化的关键地区。 本文根据GPS多年监测数据，采用GAMIT／GLOBK软件，进行综合分析处理，得出了多个参考框架的运动速度场。通过对不同参考框架及不同剖面的测站速度变化趋势分析，探讨了研究区的地壳运动特征。以欧亚参考框架下速度场为基础，采用刚性假设下最小二乘法对研究区地块、断裂进行了研究，得到了各地块的平移、旋转速度矢量以及主要活动断裂的性质、大小。以此为据，对青藏高原东部及邻区运动学、动力学机制进行探讨。 GPS研究表明：自西向东，研究区测站运动速率总体上逐渐变小。鲜水河断裂北部地区运动速率最大，向两侧逐渐变小。运动方向则自北向南，由西向东，逐渐由北东向转为南东向，呈现出顺时针旋转特征。 地块活动特征研究表明：柴达木地块、甘青地块、华南地块、川滇地块、印支地块的现今运动速率分别为11.95±2.89、11.86±2.32、7.83±2.08、13.18±2.43、6.45±1.95 mm／a；地块运动方向为61.1°、93.8°、113.1°、134.8°、141.6°；地块旋转速率为2.91、6.91、0.38、2.15、1.45(×10^-9rad／a)。各块体围绕东喜马拉雅构造结作顺时针旋转。 断裂运动速率及性质的研究表明：龙门山断裂以右行挤压走滑为主，运动速率为1.67±2.07 mm／a，断裂南段活动性比北段要强；鲜水河断裂为左行走滑断裂，活动性较大，运动速率为8～10mm／a；小江断裂为左行走滑断裂，运动速率为6～8mm／a左右；红河断裂为右行走滑断裂，中段断裂速率为3.65±1.95mm／a，南段断裂速率为1.59±1.94mm／a。 青藏高原东部及邻区地壳运动和变形与其动力学机制密不可分。印度板块向北俯冲、推挤是其动力根源。青藏高原物质的挤出、下地壳的黏性流动和外界水平推力作用导致块体的平动、旋转及断裂的活动。地块、断裂表现更多还原

【Abstract】 The eastern Qinghai-Tibet plateau and adjacent areas is the most typical mainland lithosphere distortion zone. The long-term tectonic activity formed a series of great scale active faults that divided plateau crust into blocks in different size and shape. Thus, blocks and faults constitute the main tectonics frame in this zone. The region possessing the complex and variety particularly geological tectonics is key zone to study the deformation of crust、 formation and evolution of Qinghai-Tibet plateau.By way of Synthetically computation to the GPS measurement data in GAMIT/GLOBK software, the velocity field on different reference framework has been obtained. According to the velocity field varying in different reference framework and sections, the characteristics of crustal motion has been discussed. At the same time, on the basis of velocity field on the Eurasia reference framework, velocity vector about motion and rotation of blocks as well as active character of faults was gained by means of least squares fitting under the hypotheses of rigid mass. As a result, the mechanism of kinematics、 dynamics in Qinghai-Tibet plateau had been discussed.GPS measurement shows that: from east to west, the GPS stations velocities gradually become smaller. In the northern region of Xianshuihe faults, GPS stations velocity is biggest and gradually become smaller toward south and north. The directions of stations movement gradually transfer from NE to SE indicating clockwise vortex feature.Studying to motion of blocks indicates that: The modern velocities of Qaidam、 Chuan-Qing、 South China、 Chuan-Dian、 Indian China block movement are 11.95±2.89、 11.86±2.32、 7.83±2.08、 13.18±2.43、 6.45±1.95 mm/a, respectively;Movement directions of blocks are 61.1°、 93.8°、 113.1°、 134.8°、 141.6°,respectively;Rotation velocities of blocks are 2.91、 6.91、 0.38、 2.15、1.45 (×10^-9 rad/a), respectively. Every block rotates clockwise around the Eastern Himalayan syntaxis.Studying to velocities and nature of faults also indicates that: The Longmen更多还原