关键词: 漾濞Ms6.4地震, 重力变化, 四象限, 重力梯度带, 重力变化异常指标

Abstract: The adjustment analysis of the relative gravity data of Yunnan Province was carried out to obtain the relationship between the change of the regional gravity field and the Ms6.4 earthquake in Yangbi area. The results shows: ①The gravity change of the epicenter location is weak from 2018 to 2021. The gravity changes drastically and shows four-quadrant features in the six months, one years, two years and four years; ②For the short-term and multi-year gravity changes, The high gradient zone of the gravity field is concentrated between the Yangbi-Xiaguan area, and the zero-value line alternately appears in this area before the earthquake; ③The multi-year gravity changes show that the gravity changes on the west side of the Nanjian-Weishan fault is negative, and the east side is positive; ④Analysis based on gravity anomaly indicators over one-year period shows that, the magnitude of the anomalous gravity change is 75×10-8m·s-2, and the range of the abnormal gravity change is about 130 km.

Key words: Yangbi Ms6.4 earthquake, gravity change, four-quadrant, gravity gradient zone, anomaly Index of Gravity Change