Abstract: In order to investigate seismicity in the peripheral areas of the Ordos block after the 2008 Wenchuan earthquake, we analyzed evolutive course of the current vertical deformation in the Fenwei fault-depression zone using fault-crossing leveling data situated on different locations. The following are obtained: ① the vertical movement extent of ascending and sinking difference is about 20 mm, and there is no obvious exceptional deformation; ② Small earthquake activities may be transient instability of horizontal stress field of Ordos block, due to adjustment of compressional stress from Qinghai-Tibet plate and relative strengthening of compressional stress from North China sub-plate.

Key words: Fault-crossing leveling, Vertical deformation, the 2008 Wenchuan earthquake, Seismicity