A model with topography was designed. Using the finite difference method, the authors studied the effects of topography on the apparent resistivity and phase curve of MT. Through an analysis and study of distortion curves of simulating models, a number of useful conclusions have been reached. It is shown that the apparent resistivity of TM mode is more easily affected by terrain than that of TE mode, and is more easily distorted at the top than on the bottom of a hill. Meanwhile, theoretical model and real data processing results indicate that the two-dimensional inversion with terrain is very effective and suitable to eliminating the effect of topography on the MT responses.
[1] Wannamaker P E,Stodt J A,Rijo L.Two-dimensional topographic responses in magnetotellurics modeled using finite element [J].Geophysics,1986,51:2131.
[2] Reddig R P,Jiracek G R.Topographic modeling and correction in magnetotelluric [J].Technical program and biographies.54th Annual International SEG Meeting and Exposition,1984,44.
