中文摘要：

汶川8.0级地震的同震形变在郫县、绵阳、中江和成都等GPS测站的水平形变分别达70 cm、31 cm、23cm、20 cm,变形方向约N45°W,垂直于断裂带方向,且成都平原呈下降趋势。动态GPS数据处理结果显示,地震的动态变形在郫县达1 m。根据四川GPS网络参考站各站记录的汶川地震的确切发震时间,反算得到了汶川地区S波的平均传播波速。

英文摘要：

Before and after the Wenchuan Ms8.0 earthquake on 12th May 2008,the coseismic deformation changes greatly,the horizontal deformation at PIXI,MYAN,ZHJI and CHDU GPS stations reached 70 cm,31 cm,23 cm,20 cm respectively.The most deformations are towards northwest 45°,nearly the orthogonal direction of the fault,and the right region,i.e.Chengdu plain of the fault appears downward.The results of kinematic GPS data processing show that the maximum deformation of PIXI reached about 1 m during the earthquake.At last,on the basis of the region time recorded at the stations of the Sichuan GPS network,the average S wave velocities from Wenchuan to all the GPS stations of the network are computed.