Modeling & Inversion Algorithms Of 3-D MT Field And Their Comparison

Being one of the important branches in geophysics and having the particularadvantage, magnetotelluric sounding (MTS) have been exploiting widely in explorationgeophysics. One of the major limitations for the application of MTS is the lack of validmodeling and inversion software. The numerical modeling and inversion for 3-Delectromagnetic fields is very complex, and it is one of the active research fields inapplied geophysics.We investigated some theories about magnetotelluric modeling and inversion,carefully studied the algorithm of magnetotelluric 3-D modeling using staggered-gridfinite difference method and 3-D rapid relaxation inversion for the magnetotellruicmethod, and the algorithm of 3-D electromagnetic modeling and inversion usingintegral equation solution. In the same time, we also designed some theoretical modelsand compute their responses synchronously using the parallel program, magnetotelluric3-D modeling using staggered-grid finite difference method developed by ChinaUniversity of Geosciences, Beijing, and the stand-alone software, 3-D electromagneticmodeling using integral equation solution written by Gabor Hursán and MichaelZhdanov, Department of Geology and Geophysics University of Utah.In the final of the paper, using the parallel program 3-D rapid relaxation inversionwritten by China University of Geosciences, Beijing, the 3-D inversion result of atheoretical model and an actual example will be showed.