A test study of 2D joint inversion of marine CSEM and MT based on unstructured triangular grid
AI Zheng-Min1,2(), YE Yi-Xin1,2, TANG Wen-Wu1,2, CHEN Xiao1,2, DU Jia-Ming1,2
1. Fundamental Science on Radioactive Geology and Exploration Technology Laboratory, East China University of Technology, Nanchang 330013, China 2. School of Geophysics and Measurement and Control Technology, East China University of Technology, Nanchang 330013, China
In this paper, an unstructured triangular grid combined with a fast Occam algorithm is used to carry out a two-dimensional joint inversion study of marine controlled source electromagnetic (CSEM) and magnetotelluric (MT) data. The unstructured triangular grid can accurately simulate undulating terrain and complex geological structures. Fine meshing is used for the inversion target area, and the other area is divided by coarse meshing, which reduces unnecessary calculations under the premise of meeting accuracy. For the purpose of realizing the joint inversion, the CSEM and MT data are assembled to the same inversion data set, and the relevant weight factors of the CSEM and MT data are constructed from the joint inversion data weight formula, which controls the fitting weights of different data. Finally, inversion calculations are performed on different models, and the results show that the joint inversion has a higher degree of recovery of seafloor structures and anomalous bodies than a single inversion, which verifies the reliability of the joint inversion algorithm.
艾正敏, 叶益信, 汤文武, 陈晓, 杜家明. 基于非结构三角网格的海洋CSEM和MT二维联合反演研究[J]. 物探与化探, 2021, 45(1): 149-158.
AI Zheng-Min, YE Yi-Xin, TANG Wen-Wu, CHEN Xiao, DU Jia-Ming. A test study of 2D joint inversion of marine CSEM and MT based on unstructured triangular grid. Geophysical and Geochemical Exploration, 2021, 45(1): 149-158.
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