The calculation of magnetotelluric quantities for three-dimensional conductivity inhomogeneities

Abstract Three-dimensional numerical modeling is applied to magnetotelluric principal axis and tipper analysis. Calculations of the impedance, rotation angles, and tipper azimuths are made at the surface of a conducting half-space which contains perturbed two-dimensional models. The object is to determine which of the directions is less disturbed by the perturbations, and hence is the more reliable guide to probable strike direction. The results indicate that the principal axis direction is a marginally more stable indicator of strike direction than is the tipper azimuth.