重磁2.5D/3D互相约束反演技术在三维地质填图中的应用研究

Application of mutually constrained 2.5D/3D gravity and magnetic inversion method to 3D geological maping

三维地质填图为我国启动的新一轮地质调查项目,为提高重磁资料在三维地质填图中的应用效果,笔者提出重磁资料2.5D/3D相互约束重磁反演技术方案:利用重磁资料2.5D剖面反演结果、3D物性反演结果作为彼此反演约束条件,并通过了理论模型试验。试验结果表明,该技术方案使反演结果中物性参数、空间位置更接近理论模型体。通过对本溪—临江地区思山岭铁矿磁异常及酸性岩体重力异常进行反演实践——估算磁异常铁矿资源量、研究酸性侵入岩深部展布形态的效果良好,可为大面积三维填图提供有效途径。

The 3D maping is a new geological survey project of our country.In order to improve the effect of gravity and magnetic data in geological mapping the author put forward a mutually constrained 2.5D/3D inversion schedule with condition of mutual constraint of inversion of the 2.5D gravity and magnetic survey profile and that of 3D properties inversion.The theory model has been tested and the result shows that physical property parameter and spatial position designed in the schedule is closer to bodies of the theoretical model.Inversion of magnetic anomly of Sisanling Fe deposit and gravity anomly of acid intrusive body in Benxi-Linjiang area are carried out to estimate iron ore resources and outline distribution of the body to depth.The result is good thus the method is a useful tool for 3D mapping in large area.