Interface effects on the propagation constant and fields of a bare conductor buried in a lossy half-space

The determination of the propagation constants and fields for conductors embedded in a lossy half-space is considered. Attention is given to the effects on the propagation constants and fields when the conductor is in close proximity to the interface. V.M. Machado and J.F.B. da Silva (1988) formulated the series impedance of a buried conductor in the presence of the interface under a uniform axial current assumption, thus neglecting displacement currents. To stud this problem, the propagation constants, associated current distributions, and fields for the discrete characteristic modes supported by a bare conductor buried near a lossy planar interface are determined using an integral equation approach. The effect of the lossy interface is incorporated using Sommerfeld-type integrals, these including both conduction and displacement current effects. At the frequencies of interest, the conductor dimensions will be much less than the skin depth in the earth; thus, an axially directed current with an arbitrary azimuthal distribution is assumed in the formulation.<>