全球五大板块的运动和形变──用卫星激光测距数据导出的站速度分析

STUDY OF PLATE MOTION AND CRUSTAL DEFORMATION FROM SATELLITE LASER RANGING SITE VELOCITIES

根据德国卫星激光测距（ＳＬＲ）数据分析中心ＧＦＺ对１９８０年１月－１９９１年７月获取的ＳＬＲ观测数据处理后得到的４１个ＳＬＲ站的站速度，解算了北美、欧亚、太平洋、南美和澳大利亚板块之间的相对运动欧拉矢量，得到了第１个ＳＬＲ实测的板块运动模型ＳＰＭＭ１．与地学板块模型ＲＭ２和ＮＵＶＥＬ－１的比较指出，ＳＰＭＭ１大体上与地学模型一致，与ＮＵＶＥＬ－１更为接近；ＳＰＭＭ１的欧亚与北美板块相对运动欧拉极与ＮＵＶＥＬ－１的相应极很接近，但旋转速率明显偏小．还分析了各板块上ＳＬＲ站的局部形变特征．欧亚板块东部和西部存在１０－２０ｍｍ／ａ的相对运动；板块边界附近ＳＬＲ站的残差站速度基本上反映了该边界的构造形变特征．

According to site velocities of SLR stations provided by Germany SLR data analysis center GFZ from Satellite Laser Ranging to LAGEOS(1980-o1-1991-07),we derived an instantaneous plate motion model(SPMM1) for the first time in this paper.SPMM1 includes 10 Euler vectors between 5 plates(Eurasia,Pacific,North America,South America and Australia),the comparison with the geological plate motion models RM2 and NUVEL-1 indicates that SPMM1 is roughly consistent with the geological models,and matchs better NUVEL-1.EURA-NOAM pole of SPMM1 is very closed to the pole NUVEL-1,but its rotation rate is obviously smaller than that of NUVEL-1,so we may conclude that EURA-NOAM plate motion has become slow in recent 3 million years.According to residual site velocities,we also analysed local deformation feature of SLR stations on Eurasla,North America,Pacific plates.There is 10-20mm/a relative motion between western and eastern Eurasia;the residual site velocities of SLR stations near plate boundaries can describe tectonic deformation feature of these boundaries better.