Abstract：The repeated gravity data of western Yunnan in 6 terms from 1994 to 1996 were used to calculate the dynamic change of gravitational differentiation by means of adjustment. The density change images of underground materials were obtained with 3D inversion combining the model of body growing and genetic algorithm. The results show that the regional density change images basically reflect the dynamic evolution process of medium density before and after the Lijiang Ms 7.0 earthquake in the south central region of epicenter;decreasingaccelerated decreasing decelerated decreasingearthquake increasing accelerated increasing is the trend of density change before and after the earthquake in the region of epicenter and relative stabilizationincreasingdecreasingaccelerated decreasingearthquakeincreasing is the progress of density change before and after the earthquake in the southern of epicenter region，it proves that there is the mechanism of volumetric dilatancy before earthquake.
Xuan Songbai,Shen Chongyang,and Li Hui. ON 3D INVERSION FOR CRUSTAL DENSITY CHANGE BEFORE AND AFTER LIJIANG Ms7.0 EARTHQUAKE[J]. jgg, 2010, 30(1): 14-20.
