中文摘要：

对鲜水河断裂南段康定和石棉两个剖面的GPS观测结果的研究表明：离断层较近的站点,由汶川地震前的左旋走滑变为震后的右旋走滑、震前的挤压变为震后拉张;不管是右旋走滑量、拉张量,还是影响范围,汶川地震对石棉剖面的影响明显大于对康定剖面的影响;由于鲜水河断裂南段具有左旋走滑背景,汶川地震的发生在一定程度上缓解了鲜水河断裂南段的地震危险性。

英文摘要：

The GPS observation results showed that an obvious change took place in two southern profiles of Xianshuihe fault after the Wenchuan Ms8.0 earthquake.Movements of sites close to the fault were of from pre-seismic left-lateral strike-slip to post-seismic dextral strike-slip,from pre-seismic compression to post-seismic tensile.The impact of the Wenchuan earthquake on profile Shimian is bigger than that on profile Kangding in dextral strike-slip,tensile and scope.The impact of the Wenchuan earthquake wasn＇t obvious on sites farther away from the fault.The seismic hazard of southern segment of Xianshuihe fault might declined in a certain extent with the Wenchuan earthquake,because of background of left-lateral strike-slip.