地球表层运动和变形的GPS描述  

GLOBAL CRUSTAL MOTION DEDUCED FROM GPS OBSERVATIONS

作　　者：黄立人[1] 郭良迁[1] 

机构地区：[1]中国地震局第一监测中心,天津300180

出　　处：《地学前缘》2003年第U08期17-21,共5页Earth Science Frontiers

基　　金：科学技术部基础研究重大项目前期研究专项"中国大陆现代地壳运动研究"(2 0 0 1CCB0 110 0 )

摘　　要：利用IERS所公布的分在全球各大构造板块上的 6 5 7个GPS、SLR和VLBI连续观测站在ITRF框架下的速度场资料 ,采用刚体板块运动 +板块整体均匀应变 +板块内局部不均匀应变的变形分析模型 ,研究了全球各主要板块的运动和变形。结果表明板块的整体变形在统计上均不显著。在一级近似上板块间表现出来的整体相对运动显著 ,根据这些运动参数定量研究了板块边界的相对运动的大小和性质。认为地球的双重不对称变形可能主要表现为南北、东西两半球所含的板块边界的运动方式不同所致。板块内的局部不均匀变形明显 ,为板块内部可能应划分成次一级的活动地块提供了佐证。由于观测点分布的密度和均匀性不足 ,本文未能就板内不均匀变形作进一步的深入讨论。Under the deformation analysis model composed of rigid plate motion + uniform strain of the plate + inner non-homogeneous strain of the plate, the movement and deformation of each main plate of the globe have been studied based on the velocity field data announced by IERS in the frame of ITRF2000 at 657 GPS,SLR and VLBI stations distributed on main plates. The results indicate that the entire uniform strain of each plate is not significant statistically. In the first order approximation, the plates show significant relative motions between each other. According to the plate motion parameters, the magnitudes and properties of the relative motion along the plate boundary zones have been studied. It is pointed out that the dual-asymmetrical deformation might be mainly caused by the differences of motion patterns along the plate boundaries distributed in the south-north hemispheres and east-west hemispheres. The local non-homogeneous strains inside the plates are significant, which indicate that some plates may need to be further divided into some secondary active blocks. Unfortunately, for the lack of enough density and homogeneity of the distribution of observation points, the intraplate non-homogeneous deformation have not been discussed deeply in this paper.

关 键 词：GPS速度场 板块运动 ITRF2000 变形 板块边界带 

分 类 号：P315.2[天文地球—地震学]