ALGORITHM IMPROVEMENT OF THE TILT-ANGLE DERIVATIVES METHOD FOR LOCATING MAGNETIC SOURCE
SHI Lei1,2, GUO Liang-hui1,2, MENG Xiao-hong1,2
1. Key Laboratory of Geo-detection of Ministry of Education, China University of Geosciences, Beijing 100083, China;
2. School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China
Abstract:Tilt-angle derivatives method requires no source property and structural index and can quickly estimate magnetic source boundary location and depth distribution, thus having good prospect in rapid interpretation of large-area magnetic anomalies. In this paper, the authors present some algorithm improvements based on Salem's tilt-angle derivatives method. Finite difference method is used in space domain to convert horizontal derivatives of magnetic anomalies, and ISVD algorithm is employed to convert high-level vertical derivatives of magnetic anomalies. A method is also presented which combines the filtering generalized tilt-angle total horizontal derivatives of magnetic anomalies with screening the effectiveness of source depth to remove bad solutions. Theoretical model test shows that this method is simple and quick, and hence its effect is obvious.
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