The Electromagnetic Response of a Conductive Inhomogeneity in a Layered Earth

A numerical model has been constructed to determine the three‐dimensional electromagnetic fields in the vicinity of a finite, thin, conductive plate buried in a horizontally stratified, conductive environment. The EM source is a rectangular loop. The problem is formulated as an integral equation for the electric field in the plate. However, to avoid certain numerical difficulties, the actual working variables are a pair of scalar potentials which represent divergence‐free and curl‐free current flows in the plate, and whose values are known at the nodes of a rectangular grid. The basic integral equation is then reduced to a set of linear equations which can be solved numerically.The cases modeled are a simulation of the Turam method. The models were a shallow plate and a deep plate in a conductive half‐space, a deep plate in an insulating host rock under a conductive layer, and a deep plate in a conductive host rock under a conductive layer. In all cases, the top of the plate was separated from the overbur...