摘要
本文给出一种用积分方程法配合有限差分法计算位于导电介质中三维导体的电磁响应的新途径,在二层大地条件下给出了具体计算方法和结果。详细讨论了围岩介质的导电性对导体异常的影响。这对于开展低阻覆盖层地区的电磁法工作具有一定的指导意义。
This paper presents a new integral equation to describe the EM response of a 3D body in layered earths. The inhomogeneities of the body are replaced by an equivalent current distribution. This current contains both collective and vortex current. A matrix equation is constructed by using the electric tensor Green's function appropriate to a layered earth. We can first obtain vortex current from the primary magnetic field by the finite-difference method. The total scattering current of the body is obtained by solving this equation. Finally, the scattered magnetic fields are found by using the magnetic tensor Green's function.The effects of varying excitation-frequency, conductivities of the host rock and the overburden have been studied in detail for a horizontal loop source fixed on a 2-layered earth with a prismatic inhomogeneity situated in the lower conductive half space.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
1989年第4期423-432,共10页
Chinese Journal of Geophysics
关键词
导电介质
三维导体
电磁响应
Three-dimensional conductor, Electromagnetic induction.
