Marine geomagnetic field modeling based on equivalent source technology
WANG Jun-Lu1,2(), WANG Meng3(), CHEN Hui1,2, ZHANG Xiao-Fei1,2, ZHENG Yuan-Man4, YU Bing1,2, NIE Hui-Zi5
1. Development and Research Center, China Geological Survey, Beijing 100037, China 2. Technical Guidance Center for Mineral Resources of Ministry of Natural Resources, Beijing 100037, China 3. China Aero Geophysical Survey and Remote Sensing Center for Natural Resources, Beijing 100083 4. School of Earth Exploration and Information Technology, China University of Geosciences (Beijing), Beijing 100083, China 5. China Aerospace Planning and Design Group Co., Ltd,Beijing 102627,China
To address the key issues in marine geomagnetic field modeling, this paper systematically explored the theoretical basis, modeling method, and optimization strategy of the equivalent source technology. By analyzing the geometric parameters and spatial configuration strategies of equivalent sources, a terrain-following vertical hexahedral equivalent source configuration scheme was proposed, significantly enhancing the accuracy of magnetic field models. In terms of algorithm implementation, a sliding window-based coverage calculation scheme was employed, effectively overcoming the bottleneck in the high-precision processing of massive magnetic survey data. Experimental results show that maintaining an overlap rate of 15%~20% in the sliding window ensures both boundary continuity and optimal computational performance. This method provides a reliable technical support for high-precision marine geomagnetic field modeling, with its effectiveness having been verified across various geological models (with the errors less than 5%).
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