郯庐断裂带中段三维密度结构反演与解释

为深入理解研究区的构造运动规律，进一步探求地壳物质可能的运移模式，本文基于Crust1.0地壳结构模型和最新莫霍面深度模型对自由空气重力异常数据进行联合约束，采用三维重力反演技术得到了郯庐断裂带中段的三维密度结构。反演结果显示，研究区的背景场稳定，断裂构造发育部位表现为重力密度低值，特别是营潍断裂带正处于大范围的重力密度低值区并纵贯整个研究区，由此可推断重力密度低值区可指示断裂构造的存在。 

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.