Abstract Using recent years flow gravity measurements from northeast China, we analyze in detail the time series variation characteristics of the flow gravity points around the Qianguo MS5.8 earthquake swarm. Based on the variation of gravity segment difference, the index values G and C are introduced to the whole and local gravity variations in northeast China, which reflects the degree of anomaly significance. Finally, we do 3D density inversion of the dynamic change of gravity field before the Qianguo MS5.8 earthquake swarm. The results show that: (1) The gravity variations on both sides of the seismogenic structure have obvious differences, which can be used as a sign to identify the tectonic activation or decoupling motion. (2) As a new method to describe the variation of regional gravity field, the significant indices G and C can provide a new idea for quantitative description of seismic gravity precursors. (3) The inversion results of gravity variation before the earthquake show that the earthquake occurred in the transitional region of mass migration, and the vertical inversion results have a certain significance for revealing the focal depth of this earthquake.
WANG Tongqing,ZHANG Pin,LIU Jinzhao et al. A Study of Qianguo MS5.8 Earthquake Swarm Based on the Variation of Gravity Point, Section Difference, and 3D Inversion[J]. jgg, 2019, 39(5): 469-475.
WANG Tongqing,ZHANG Pin,LIU Jinzhao et al. A Study of Qianguo MS5.8 Earthquake Swarm Based on the Variation of Gravity Point, Section Difference, and 3D Inversion[J]. jgg, 2019, 39(5): 469-475.
