基于磁导率的频率域航空电磁法双频反演方法  

Frequency Domain Airborne Electromagnetic Dual-Frequency Inversion Method Based on Magnetic Permeability

作　　者：王卫平[1] 曾昭发[2] 吴成平[1] 李静[2] 黄玲[2] 

机构地区：[1]中国国土资源航空物探遥感中心,北京100083 [2]吉林大学,长春130026

出　　处：《地质科技情报》2013年第2期181-186,共6页Geological Science and Technology Information

基　　金：国家自然科学基金项目(41174097);国家矿保工程"高精度航空物探方法研究"(1212011087010)

摘　　要：以往的频率域航空电磁法数据反演方法中,通常在模型中以真空磁导率代替介质磁导率,忽略了磁性层影响。但在高磁性区域,这样做将会导致计算电阻率值偏高。针对这一问题,首先根据层状介质模型研究了考虑磁导率和电阻率因素条件下的电磁场正演计算方法,并且分析了不同磁性介质对频率域电磁响应的影响规律。在此基础上,提出了磁导率和电阻率的双频反演方法,电阻率是通过2个频率的虚分量之比计算得到的,计算结果更加可靠,提高了磁性区域视电阻率填图的精度。通过对模型计算和实测数据进行反演计算,表明这种方法具有较高的反演精度,为强磁性区域航空电磁法视电阻率填图提了供一种行之有效的反演方法。In conventional frequency-domain airborne electromagnetic inversion method,the geological layer is usually considered as non-magnetic layer which affects the inversed resistivity value in high magnetic permeability region and therefore results in wrong geological interpretation.In order to solve this problem,we studied the helicopter electromagnetic（HEM） simulation algorithm with magnetic permeability and resistivity based on layered medium model.We also analyze the frequency domain electromagnetic responses with different relative magnetic permeability value from 1 to 10,which shows that the magnetic permeability has large response on the EM simulation results.Based on the study,we developed a dual-frequency inversion algorithm for the frequency domain airborne electromagnetic data and got resistivity and permeability.The resistivity is calculated from the ratio of two frequencies imaginary data.The inversion result is more stable and accurate.The inversion results can be used as a parameter for magnetic areas mapping.According to the study,we develop the software and verified it by theoretical simulation data and HEM measurement data from Miyun area.The results show the software has high accuracy and efficient in application.

关 键 词：频率域航空电磁法 双频反演 磁导率 电阻率 

分 类 号：P631.2[天文地球—地质矿产勘探]