磁化强度矢量反演新方法及其在卡拉塔格铜多金属矿床找矿中的应用

New magnetic vector inversion methods and application to 3D geology characterization of a copper polymetallic deposit in Kalatage exploration area

磁异常的反演是地球物理勘探的重要手段,三维磁化率反演是磁异常定量解释中的一种重要方法.由于剩磁的存在使得磁化方向与地磁场方向产生偏差,从而影响了磁异常反演与解释的精度.本文基于磁异常模量反演和磁化强度矢量反演方法得到了一种新的磁化强度矢量反演方法.与以往的磁化强度矢量反演方法相比,该方法以磁异常模量反演得到的磁化率模型为约束,采用Lp范数正则化方法求解,提高了磁化强度矢量反演的精度和效率.本文通过模拟试验的反演计算,验证了这种磁化强度矢量反演方法的有效性.最后,将本文方法应用于新疆东天山卡拉塔格地区航磁数据的解释,获得了地下空间不同磁性差异的磁性体的空间分布特征,为进一步分析研究区隐伏矿床提供了重要信息.

Magnetic anomaly inversion is an important means of geophysical exploration,and 3D magnetic susceptibility inversion is an important method in the quantitative interpretation of magnetic anomaly.Because of the existence of remanence,the direction of magnetization deviates from that of geomagnetic field,which affects the accuracy of inversion and interpretation of magnetic anomaly.In this paper,we propose a new magnetic 3D inversion algorithm based on the inversion of magnetic anomaly modulus and magnetic intensity vector.Compared with the previous inversion methods of magnetic intensity vector,this method is based on the magnetic susceptibility model obtained by magnetic anomaly inversion and the Lp norms regularization solve,which improves the accuracy and efficiency of magnetic intensity vector inversion.Then inversion calculation of the simulation test is used to verify the validity of the new inversion method.Finally,the method is applied to the interpretation of aeromagnetic data in Kalatage area,Xinjiang.The spatial distribution characteristics of different magnetic bodies are obtained,which provides important information for further study of concealed deposits in the area.