Analysis on seismicity characteristics of Huayingshan fault zone

Based on the analysis of earthquakes with M≥5 in Huayingshan fault zone and the present moderate and small seismicity, the background and regional seismicity characteristics in this area are discussed. It is considered that the southern section of the fault zone is the main seismicity area, especially in Yibin, followed by the middle and northern sections. The distribution characteristics of “quiet-active” period of earthquakes with M≥5, the law of “weak activity-enhancement” of earthquakes with M≥3, and the acceleration of strain energy release rate after Changning M_S6.0 earthquake in 2019 provide references for the prediction of earthquakes with M≥5 in this area.