CSAMT探测中电场Ex全区视电阻率定义及应用

Application of full-region apparent resistivity of CSAMT Ex in exploration

讨论了CSAMT电场x方向全区视电阻率定义及应用。采用积分方法将多个电偶极子叠加,获得双极源电磁场,均匀半空间的计算结果表明该方法是可行的。通过对二、三层电性断面的视电阻率计算,并与卡尼亚视电阻率、波区视电阻率对比,说明了该方法的优越性。实测CSAMT资料的计算结果表明,用电偶极子定义的CSAMT电场Ex方向全区视电阻率较好地反映了电性断面的特征。该方法对CSAMT深部探测具有实用价值,对于简化野外工作方法、减轻野外数据采集的强度及解决卡尼亚视电阻率的近场源问题具有重要意义。

This paper discusses the definition and application of full-region apparent resistivity by using CSAMT method to explore the electric field in x-direction. Integral method is used to superimpose multiple electric dipoles to obtain electromagnetic field of bipolar source. The results calculated in the homogeneous half space show that the method is feasible. Computation of the apparent resistivity of the two or three layer sections and comparison between Cagniard apparent resistivity and the apparent resistivity in wave zone show the advantage of this method. The result calculated by the CSAMT can reflect the characteristics of the electrical section better through using the CSAMT method defined by the electric dipole to explore electric field in x direction. This method has practical value for the deep exploration, simplifying the field work, reducing data collection in field and solving the near field source problem in measuring Cagniard apparent resistivity.