Forward modeling of well-ground direct current resistivity method for undulating terrain based on Gmsh
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摘要: 采用Gmsh软件对起伏地形下的异常体模型进行建模和不规则网格剖分,将剖分网格数据应用到2.5D有限元正演程序中,并使用井—地联合观测方法对正演计算结果进行分析。分析结果表明:采用不规则网格剖分拟合起伏地形和使用井—地联合观测方法来进行起伏地形下的地质情况勘探能得到较好的结果,同时还研究了使用不同观测装置时山谷地形对下方异常响应的影响,研究结果对实际勘探工作有借鉴意义。研究证明了有限元软件Gmsh在地球物理有限单元法正演建模和网格剖分方面有良好的应用价值。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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Key words:
- Gmsh /
- well-ground observation devices /
- undulating terrain /
- finite element method
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