Numerical modeling of geophysical structures excited by an electromagnetic wave

The numerical solution for the electromagnetic response of inhomogeneities of any shape in the ground has been developed for a plane wave or electric or magnetic dipole excitation. Two approaches are usually used depending on the structure of the ground in which the inhomogeneity is embedded. For a horizontally stratified ground, the solution is obtained in the form of an integral equation system, while for a heterogeneous medium, the finite element or the finite difference method is used. A brief review of these techniques is made, and examples of application are given. Furthermore, the limitations of each of these models are outlined.