大同6.1级地震前后首都圈重力场动态变化图像

Dynamic Gravity Change in Beijing Area before and after M_S6.1 Datong Earthquake

采用具有绝对测量结果的时间基准,对1986-1996年首都圈重力网的观测资料进行动态变化计算,给出大同6.1级地震孕育过程中首都圈重力场演化图像。结果显示,大同6.1级地震孕育的显著特征为持续3年的正重力变化,与该地震孕育有关的重力场变化呈上升—加速上升—下降的状态,与唐山地震孕育过程的重力场变化特征相似。

We compute the observed data provided by the gravity network in the capital area of Beijing in the period from 1986 to 1996,and get the danamic pattern of the gravity field in the capital area during the seismogenic process of the MS6.1 Datong earthquake in 1989 in Shanxi Province.We find that the positive gravity variation lasted for 3 years in the seimogenic process of the earthquake.The variation patttern is ascent,accelerated ascent,and descent,which is similar with that in the seismogenic process of the MS7.8 Tangshan earthquake in 1976.