Abstract：The experimental base for surface deformation simulation is designed and simulation test is carried out，and 1 Hz GPS data obtained from the simulation test is processed and analyzed with the single epoch single point positioning of the Bernese 5.0 software.Taking the Wenchuan earthquake on May 12，2008 as an example，we obtain the time series of the shortimpending displacement before the earthquake and shortly after the earthquake at 3 GPS stations:CHDU，JYAN，PIXI.The results after data processing show good consistency among the deformation results at all stations in time.On the basis of 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 3.17 km/s.
