以远距离的IGS武汉GPS站为参考站,用超长基线双差瞬时精密定位技术,获取汶川Ms8.0地震震时震区连续GPS站1 Hz动态形变序列.同时以较近距离的雅安站为参考站解算动态形变序列,结果显示,两者的形变结果具有很好的一致性.距离断层较近的郫县、成都、绵阳、中江等站形变较大(形变最大的郫县站最大振幅达1.034 m);位于震中南侧的邛崃、雅安等站形变较小.利用动态时序的地震波到时和震中距离估计地震波地壳平均速度为3.1 km/s.%We used Wuhan, one of IGS stations, as a reference to form ultra long baseline and solve instantaneous 1-Hz-GPS positions and measure the co-seismic kinematic deformations caused by Wenchuan earthquake. Compared with the results from using Yaan as the reference which is nearby 1 -Hz-GPS stations, the deformation solutions show good consistence with different reference stations. The maximum deformation amplitude is found for station Pixian, which had the largest deformation about 1.034 meter. The deformations of stations, such as Pixian, Chengdu, Mianyang, Zhongjiang are relatively larger and also show the propagation direction of seismic waves. The smaller deformations occurred in Qionglai, Yaan, in the south of the epicenter, which indicate that the fault ruptured from the epicenter to the northeast. On the basis of the arrival time of seismic wave recorded in kinematic time series and the distance between 1 -Hz-GPS stations and the epicenter, the estimated average velocity of seismic wave in the crust is 3.1 km/s.
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