Electromagnetic fields of a small loop buried in a stratified Earth

The field structure of a buried vertical oscillating magnetic dipole is examined. The earth is represented as a two-layer half-space, and the source is located in the bottom semi-infinite region. Using numerical integration, the magnitude of the ratio of the horizontal to the vertical magnetic field is examined for an observer on the earth's surface. It is shown that at sufficiently low frequencies, the field ratio is not appreciably modified by the finite conductivity and the geometry of the layers.