二维横向不均匀性对频率域电阻率测深的影响  

The Influence of 2DTransverse Non-uniformity on the Electromagnetic Resistivity Sounding in Frequency Domain

作　　者：张勇军 贺文根 

机构地区：[1]中化地质矿山总局化工地质调查总院,北京10013

出　　处：《工程地球物理学报》2015年第5期637-643,共7页Chinese Journal of Engineering Geophysics

摘　　要：当地表或地下存在异常体时,电性的横向不均匀性会导致视电阻率测深曲线产生畸变。为了揭示横向不均匀性对频率域电阻率测深影响的规律,首先根据高频平面电磁波的趋肤效应,计算出异常体正上方测点测深曲线受电阻率横向不均匀性影响的起始工作频率,然后利用有限元法对含低阻体的二维模型进行正演计算,总结了横向不均匀性对视电阻率测深曲线的畸变特征。研究结果表明,地下介质的横向不均匀性影响与极化模式、异常体属性(厚度、宽度、电阻率)、频率相关。It is well known that the critical distortion to resistivity sounding curves could be produced by shallow inhomogeneous bodies. In order to reveal the influence of transverse inhomogeneity on the frequency domain sounding, this paper obtained the start work frequency to impress sounding curve according to the skin effect of high frequency plane electromagnetic wave, then the forward simulation of the 2D model of the low resistance is realized by the finite element method, and the distortion characteristics of transverse non-uniformity to the resistivity sounding curves is summarized. The transverse non-uniformity of the subsurface media is related to polarization mode, abnormal body attributes （thickness, width, resistivity） and frequency .

关 键 词：横向不均匀性 有限元法 频率域电阻率测深 

分 类 号：P631.2[天文地球—地质矿产勘探]