Abstract: This paper presents the ground raising image of the area to the south of the epicenter of the Wenchuan M_S8.0 earthquake obtained from years' mobile leveling, the variation curve of Gengda short leveling across the fault on the epicenter, and the vertical and horizontal crust movement monitored by GPS in the area around the epicenter. A model for the generation of strong intra-plate thrust earthquake, shortly called PUTDOWN ( Press-Up and Thrust-Down) Model, is developed by integrated analysis and deduction, by which all the anomalies showed in the figures can be well understood coincidently.

Key words: Wenchuan earthquake, Earthquake generation model, Deformation, Leveling, GPS