Inversion for 3D density structure in the middle segment of Tanlu fault zone and its implication

Since the Cenozoic, the tectonic movement of the Tanlu fault zone has been active, and on the middle segment of Tanlu fault zone occurred many strong earthquakes in history. To better understand the tectonic movement in the studied area, further to explore the possible migration patterns of crustal material, we used the 3D gravity inversion to obtain 3D density structure of the middle segment of Tanlu fault zone, with the Crust1.0 model and the Moho relief model from ChinArray project as constraint of free air gravity anomaly data. The 3D density structure shows that the background of the studied area is stable, there were low gravity density areas in the fault structure development areas, especially Yingwei fault zone was just in a series of low gravity area throughout the studied area, therefore it was deduced that the low gravity area can indicate the existence of fault structure.