The Effect of Conductivity Anisotropy on MTEM Response in the frequency domain

The current study is an investigation of the conductivity anisotropic effects, in response of a horizontal electric dipole (HED) field located on the earth surface. Two models have been studied in this research: 1. an inhomogeneous and anisotropic two-layered Earth including a VTI (vertical transverse isotropy) anisotropic overburden with defined thickness and an isotropic substratum with infinite thickness, 2. a homogeneous and VTI anisotropic half-space.The purpose of studying first model is to find how the electric field components on earth surface changes with varying offset. In the second model, the electric field can be obtained at a certain offset for each condition in terms of frequency. Results show that the electric fields which have received on surface, change considerably with varying source-observation point and frequency in anisotropic media (with anisotropy coefficients of 1.5, 2, 3); and these changes have been compared with the isotropic case (where anistropy coefficient is 1).