摘要
文章应用有限单元法进行点源二维电场数值模拟计算。在正演过程中采用三角单元剖分网格,有利于对复杂地形的模拟。电导率(σ)和电位在相邻节点间线性变化,使得电导率和电位与实际地质构造更接近、与实际地电场变化规律更易吻合;在点源二维电场正演基础上,将一定地形条件下的二维地电模型的视电阻率响应,分解为畸变场和正常场两部分,采用比值法消除由地形起伏引起的视电阻率畸变,从而达到地形校正的目的。并通过设计几个模型及实际算例,验证该方法对地形校正的效果。
In this paper, the forward modeling of point -source electrical field on a two -dimension structure is calculated with the finite elements method applying FEM for forward simulation. In forward operation, the triangular cell is employed for the conversion calculation of the 2 - D FEM, with electrical conductivity （cr） and the electric potential in the triangular with linear change, which al- lows electrical conductivity and potential get closer to the actual geological structure, and the actual change in electric field is more ac- cordant. Based on the finite elements method forward modeling, authors divide the apparent resistivity response of 2D model into two parts： normal part and abnormal part, and remove the abnormal effects of the topography, and got the resistivity value without topo- graphic effects by using Ratio - Method. Calculating several models and observed data show that the method of FEM simulation and the terrain correction is accurate and feasible.
出处
《矿产勘查》
2011年第3期293-297,共5页
Mineral Exploration
关键词
有限单元法
数值模拟
视电阻率
地形校正
finite element method
numerical simulation
apparent resistivity
terrain correction
