Abstract
An analytical formulation is developed for the resultant electromagnetic field of an oscillating vertical magnetic dipole located over a thin conductive sheet of infinite extent. The sheet is characterized by a conductivity-thickness product or conductance σd that may be a function of the horizontal coordinates. The system of integral equations arising in the general formulation is simplified greatly when azimuthal symmetry prevails. Numerical results for a Gaussian variation of σd in the radial direction are presented for the case of a symmetrically located source. These results are for the fields at the level of the source dipole over the conductive sheet. It is shown that the quadrature response of the sheet is enhanced when there is rapid variation of the conductance. The null in the resultant wave tilt is also found to be shifted toward the direction of increasing conductance.
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Geyer, R.G., Wait, J.R. Electromagnetic fields of a vertical magnetic dipole above a laterally inhomogeneous thin layer of conductive overburden. PAGEOPH 116, 181–197 (1978). https://doi.org/10.1007/BF00878992
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DOI: https://doi.org/10.1007/BF00878992