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Forward modeling of well-ground direct current resistivity method for undulating terrain based on Gmsh |
ZHANG Yu-Zhe( ), MENG Lin, WANG Zhi( ) |
School of Electronics & Information Engineering, Yangtze University, Jingzhou 434023, China |
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Abstract This paper focuses on the forward modeling of the direct current resistivity method. To this end, the Gmsh software-a 3D finite element grid generator-was used to model the anomalous bodies under undulating terrain and conduct relevant irregular grid division. Then partial grid data generated by Gmsh were applied to a 2.5D finite element forward modeling program, and the forward calculation results were analyzed using the well-ground joint observation method. The analytical results show that good effects can be obtained by using irregular grids to fit the undulating terrain and using the well-ground joint observation method to explore the geological conditions under the undulating terrain. The effects of the valley terrain on the anomalous response below using different observation devices were also studied. The results achieved are practically significant and they also prove that the Gmsh software has great application value in the forward modeling and meshing based on the finite element method.
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Received: 26 April 2021
Published: 25 February 2022
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Corresponding Authors:
WANG Zhi
E-mail: 2795484843@qq.com;1324385898@qq.com
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Example of observation device[18]
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Two-layers geo-electric cross section
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The curve for analytical solution and calculation solution of potential
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Sketch map of model
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Apparent resistivity cross-section view of model 1(borehole-ground pole-pole device)
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Apparent resistivity cross-section view of model 2
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Apparent resistivity cross-section view of the forward result of model 2
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Apparent resistivity cross-section view of model 3
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Apparent resistivity cross-section view of the forward result of model 3
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Sketch map of model based on Gmsh
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