Abstract:

Bayan Har block and peripheral is one of the main seismogenic area of mainland China in recent years, on April 20, 2013 Sichuan Lushan 7.0 strong earthquake was happend on the southwest segment of Longmenshan fault zone, the east margin of Bayan Har block. We take the middleeast segment of Bayan Har block as the research area, based on the proseccing of observation data come from the before and after the earthquake in this region by multiphase regional level observation and GNSS station observation, it can be obtained the study area image for both of the horizontal and vertical deformation rate. Combined with regional geological structure, the earthquake induced model was established, and the explaination for the main shock and aftershock earthquake activity mechanism come from the sudden rupture of Longmenshan fault zone for the huge blocks and small block the flow of the collection. By analyzing the image both of the vertical deformation rate and horizontal deformation rate, we conclude that the earthquake was the result of the Longmenshan fault zone thrust activity, and the middle east section of east Kunlun fault zone appear the possibility of strong earthquakes occurred in future. At last, the monitor based on the regional level and GNSS measurements in the next five years is suggested as for the technical means.

Key words: Lushan earthquake, Bayan Har block, Longmenshan fault zone, seismicity