Apparent Longitudinal Conductivity Interpretation Method in Transient Electromagnetic Technique

According to the principle of equivalent conductive plane, this chapter discusses apparent longitudinal conductivity in layered media, describes its advantages, uses numerical methods (i.e., central difference algorithm) to calculate the derivative of transient response in forward processing, and uses spline interpolation method instead of solving the inverse function in traditional sense in acquiring the key value M to simplify the calculation. When verifying the effectiveness of apparent longitudinal conductivity interpretation, the forward data of typical geoelectric model of in H-type Layer 3 and HK-type Layer 4 are used to inspect. The results show that the curves of apparent longitudinal conductance can distinguish electrical layers clearly, and can also indicate the magnitude of conductance of layers, so as to achieve a good explanation.