Controlled-source tensor magnetotelluric responses of a layered earth with azimuthal anisotropy

We consider a model for fracture-generated anisotropy in the crust represented by a layered earth with azimuthal anisotropy. A theory has been developed to compute electromagnetic fields induced by grounded electric dipoles on such a model. A vector potential is used to derive fields. Reflection coefficients are obtained by matrix recurrence formulae. Comparisons with one-dimensional isotropic models and models of homogeneous half-spaces with azimuthal anisotropy show that our algorithm gives correct results. Results are presented in terms of controlled-source tensor magnetotelluric (CSTMT) impedance tensor and tipper vector. The existence and characteristics of azimuthal anisotropy are revealed by them. We suggest the use of Parkinson's vectors to delineate anisotropy in practice because magnetic fields are less susceptible to static distortion than electric fields.