赤道向频率域电磁测深三维电磁模拟技术研究

利用体积分方程和并矢格林函数理论对赤道向频率域电磁测深法三维问题进行正演模拟。对该算法的精度进行了讨论。三维异常体的存在,对频率域电磁测深法视电阻率曲线形态和拟断面图分布特征的影响,依据异常体与围岩的导电性差异不同有其特殊的规律性。选择测量电极中心作为记录点,既能使正演计算的视电阻率响应在异常体上方获得最大异常,又能使正演计算的拟断面图的异常分布与异常体之间有很好的对应关系。

Research on three-dimensional electromagnetic modeling technique in latitudinal frequency-domain electromagnetic sounding

Three-dimensional forward modeling in latitudinal frequency domain electro,magnetic sounding is conducted by using volume integral equation and dyadic Green's function theory,and the accuracy is checked up carefully. The influence of three-dimensional abnormal body upon both the response and the pseudosection of apparent resistivity in frequency-domain electromagnetic sounding depends on conductivity difference between the abnormal body and country rock. The center of measuring electrode is taken as recording point so as to cause both the apparent resistivity over a three-dimensional abnormal body to be maximum and the pseudosection to correspond with the abnormal body quite well.