Abstract:Using mobile gravity measurements from 2010 to 2016 in northeast China, we systematically analyze regional gravity field changes and variation characteristics of gravity before and after the 2013 Qianguo MS5.8 earthquake swarm. The results show that the inter-annual and dynamic changes of gravity present NW and near NS direction in the study area, which differs from the structural framework of NE and NNE direction. This suggests that the variation of gravity field is weak in structure control. Generally, gravity changes are relatively gentle in northeast China, with rarely more than 60 μGal gravity gradient zone. This phenomenon shows that the level of underground structural activity and material migration is relatively stable in an indirect way. There are obvious gravity variation characteristics during the process of the earthquake preparation before the Qianguo MS5.8 earthquake swarm and the Tongliao MS5.3 earthquake. These cause continuous accumulation of seismic energy and the occurrence of earthquake rupture. The shock recovery adjustment of the gravity field after the earthquakes will take three or more years.
WANG Tongqing,ZHAO Yunfeng,CHANG Jinlong et al. Study on the Relationship Between Recent Variation Characteristics of Gravity Field and the Qianguo MS5.8 Earthquake Swarm in Northeast China[J]. jgg, 2018, 38(3): 249-253.