航空瞬变电磁法的全时域视电阻率计算方法  

The algorithm of all-time apparent resistivity for Airborne Transient Electromagnetic(ATEM)survey

作　　者：强建科[1] 罗延钟[2] 汤井田[1] 李永兴[1] 

机构地区：[1]中南大学信息物理工程学院,长沙410083 [2]中国地质大学地球物理与空间信息学院,武汉430074

出　　处：《地球物理学进展》2010年第5期1657-1661,共5页Progress in Geophysics

基　　金：国家自然科学基金(40974076)资助;国家高科技发展计划项目(863-2006AA06Z105;2007AA06Z134)资助

摘　　要：鉴于ATEM数据量大质低的特点,视电阻率仍是最有效而直观的参数.本文给出了适用于ATEM多种观测条件下(包括各种装置类型,发送波形,关断电流等情况)的全时域视电阻率的计算方法,并对典型层状大地模型的理论瞬变电磁响应作了全时域视电阻率及其对应等效深度的计算.结果表明,全时域视电阻率随等效深度变化的曲线可定性反映地下介质电性特征,并可近似估计低阻或高阻层上界面深度.对于非单调下降的瞬变电磁曲线,该方法也能取得较好的计算结果.Taking the large amount and low quality of ATEM data into account, the apparent resistivity is still the most efficient and intuitive parameter. We present an all-time resistivity calculation technique which is suitable for a variety of observing situations （including configurations, transmitter waveforms, cut-off time and so on）, and carry out calculations of apparent resistivity and equivalent depth for typical symthetic models. The results show that the curve of apparent resistivity with equivalent depth can reflect electrical characteristics of subsurface geological medium, and the depth of conductivity/resistivity layers can be estimated. This technique can achieve favorable results for non-monotonous declining transient electromagnetic responses.

关 键 词：航空瞬变电磁法 全时域视电阻率 等效深度 

分 类 号：P631[天文地球—地质矿产勘探]