Gravity variation associated with Wenchuan earthquake in western Sichuan

Based on the data of mobile gravity observation from 1998 to 2008 in western Sichuan, spatial dynamic variation results of regional gravity field are obtained. The relationship between the gravity variation features and Wenchuan M s8.0 earthquake is systematically analyzed. The results show: 1) Gravity variation is closely related to active fault tectonics, and gravity measurement can better reflect material migration following crustal tectonic activity near active fault. 2) The gravity field appeared a wider range regional gravity variation during Wenchuan earthquake occurrence. The dynamic patterns of gravity field demonstrates the evolution process of gravity field: quasi – homogeneous state—non – homogeneous state—earthquake occurrence.