在VC 环境下，使用C 语言实现了基于四叉树网格的2.5D 直流电阻率法有限元数值模拟程序。3 个典型模型的算例被用来证明四叉树网格方案适合于复杂地电模型的数值模拟：分别使用四叉树网格和等距全网格对水平两层模型进行了计算。后一方案与前一方案相比，在数值模拟精度上没有明显的差别，而使用的网格数却有大幅度的减少；计算了覆盖层下倾斜高阻板状体模型，高阻板状体的形态、埋深清晰地显示在偶极-偶极视电阻率断面图上；仿真了中间梯度法测量2D 地形下埋藏直立高阻板状体的情形，利用比较法对计算结果进行地形改正后，高阻体的埋深被计算出来。
A geoelectric numerical modeling program based on quadtree is developed using C language under VC development environment. Three experiments are used to prove the scheme based on quadtree mesh is suitable for complex geoelectric model simulations. The first experiment is the calculation of horizontal two-layer model and the result shows that the scheme using quadtree mesh does not have significantly lower numerical simulation accuracy than that using equidistant grids, but many grids are saved. The second experiment is the calculation of the model with an inclined high-resistivity plate-like body buried, with the contour and the burial depth of the body shown clearly on the dipole-dipole apparent resistivity pseudosection. The third experiment is the measuring of the model with a high-resistivity plate-like body in the vertical direction buried under 2D terrain using intermediate gradient method. After eliminating the effect of terrain factors by the comparative method, the burial depth of the high-resistivity body is calculated.
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