The application of gravity and magnetic three-dimensional inversion based on known information constraint in deep magnetite exploration: A case study of the Nihe iron deposit in Anhui Province
Fan LUO1,2,3(), Jia-Yong YAN2,3, Guang-Ming FU1,2,3
1.School of Geophysics and Measurement-Control Technology,East China Institute of Technology,Nanchang 330013,China 2.MLR Key Laboratory of Metallogeny and Mineral Assessment,Institute of Mineral Resources,Chinese Academy of Geological Sciences,Beijing 100037,China 3.China Deep Exploration Center,Chinese Academy of Geological Sciences,Beijing 100037,China
The Nihe iron deposit is a typical porphyrite type iron deposit with large burial depth,small amplitude of gravity and magnetic anomalies generated at the surface in Anhui Province. The authors selected the Nihe iron deposit to carry out gravity and magnetic inversion experiment based on known information constraint, in order to evaluate the application effect of gravity and magnetic data fine-grained and three-dimensional inversion in magnetite deep exploration: First of all, through the model test, the authors compared the three-dimensional inversion results with different known information constraints, and then extracted the residual gravity and magnetic anomalies of the Nihe iron deposit through the targeted field separation method. Then, the authors transformed the known surface geological information into physical information, and built a remnant density and magnetic susceptibility reference model to constrain gravity and magnetic three-dimensional inversion. Based on the three-dimensional distribution model of inversion density and magnetic susceptibility body, the authors confirmed the three-dimensional spatial shape of the Nihe iron orebody, and found that the result is basically consistent with geological exploration results. According to the results, the reliability of the inversion results based on the known information constrained gravity and magnetic three-dimensional inversion could be improved. For magnetite with high magnetic and high density, this method is an effective method to find and characterize deep magnetite orebody.
罗凡, 严加永, 付光明. 基于已知信息约束的重磁三维反演在深部磁铁矿勘查中的应用——以安徽泥河铁矿为例[J]. 物探与化探, 2018, 42(1): 50-60.
Fan LUO, Jia-Yong YAN, Guang-Ming FU. The application of gravity and magnetic three-dimensional inversion based on known information constraint in deep magnetite exploration: A case study of the Nihe iron deposit in Anhui Province. Geophysical and Geochemical Exploration, 2018, 42(1): 50-60.
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