Geophysics · 1974 · 29 citations · 0 references
Abstract The impedance tensor corresponding to the magnetotelluric field for a nonisotropic one-dimensional structure is given in terms of the solutions of a sixth-order differential system.The conductivity tensor is three-dimensional. Its components depend upon depth only in an arbitrary manner such that the corresponding matrix is positive definite.The impedance tensor components are found by a numerical integration procedure based on a set of one-step methods and a variable step-size to insure a given accuracy in the final result.Calculations were made for three models having sharp boundaries and also transitional layers. The first of these models has a middle layer of high conductivity, sandwiched between two layers of linearly varying conductivity, while in the second model the middle layer has a very low conductivity. In the third model the conductivity tensor is three-dimensional and is linearly varying in one of the layers.