Crustal structure and background of earthquake occurrence in Linfen meizoseismal area

Using the velocity profile of the Zhucheng-Yichuan deep seismic sounding (DSS) profile as a constraint to fitting the high precision gravity data along the profile, we processed the plane Bouguer gravity anomaly in Linfen meizoseismal area, and obtained the crustal density structure and distribution of the plane gravity anomaly in Linfen meizoseismal area. And then we analyzed the crustal structure and tectonic settings. In combination with previous research results, it is believed that there were more plastic crustal media in Linfen meizoseismal area, and the Hongtong and Linfen historical earthquakes all took place on the elastic-plastic transitional boundary. Moreover, there were differences between north and south sides of Linfen depression in local tectonic environment. Therefore, the Linfen and Hongtong earthquakes occurred under the regional stress field with different occurrence time, epicenter location and magnitude.