【摘要】 地—井瞬变电磁法是一种使用较多的瞬变电磁法工作装置。鉴于现今国内外对其正演研究还比较少,在此实现了基于一维解析法和矢量有限单元法的地—井瞬变电磁法一维和三维正演。通过对比层状介质的一维解析解和水平板状体地电模型的数值解,验证了矢量有限单元法用于模拟地—井瞬变电磁法的有效性;通过对低阻块状体地电模型进行三维正演,分析总结了矩形回线源激发瞬变电磁场随时间和深度变化的扩散规律。更多还原

【Abstract】 The surface-borehole configuration is one of the most useful working devices for transient electromagnetic method.However,forward modeling study for this method is not very popular.In this paper,we propose one-dimensional and three-dimensional forward modeling for surface-borehole transient electromagnetic based on 1D analytical method and vector finite element method.Comparing with one-dimensional analytical solution for layered medium and the numerical solution of vector finite element method for low resistivity sheet in homogeneous half-space,the validity of the three-dimensional algorithm is proved.In addition,we analyze the diffusion characteristics of transient electromagnetic field variation with time and depth using three-dimensional numerical simulation for low brick body of low resistivity.更多还原