Magnetotelluric data 2D forward modeling based on quadtree grid
WANG Peijie1, HU Hua2,3, XU Fei3,4, GUO Huo3,4, CHEN Lianmu3,4
1. Institute of Geology, China Earthquake Administration, Beijing 100029, China; 2. School of Geosciences, Yangtze University, Wuhan, Hubei 430100, China; 3. Key Laboratory of Exploration Technology for Oil and Gas Resources, Ministry of Education, Yangtze University, Wuhan, Hubei 430100, China; 4. School of Geophysics and Petroleum Resources, Yangtze University, Wuhan, Hubei 430100, China
Abstract：A finite difference algorithm for forward modeling of magnetotelluric (MT) data based on quadtree gridding is proposed in this paper.First the model is gridded based on the quadtree data structure.Then finite difference formulas for different nodes of the mesh are derived with the method of undetermined coefficient, and the magnetotelluric responses are finally obtained by solving difference equations of nodes.The proposed algorithm is tested on several models with reliefs and its validity is proved by the comparison of conventional finite difference and finite element methods.Based on our test results, the proposed algorithm achieves much better calculation efficiency with comparable accuracy.
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