Original Article |
2007, Vol.29, No.2, pp. 565-573
Magnetic field of direct current in heterogeneous ground
Suabsagun Yooyuanyong and Warin Sripanya
pp. 565 - 573
Abstract
We derive solutions of the steady state magnetic field due to a DC current source in four types of heterogeneous earth models. Four two-layered continuously earthed models are considered : an exponential earth with a homogeneous overburden, a homogeneous earth with an exponential overburden, a homogeneous earth with a linear varying overburden, and a linearly varying conductivity earth with a homogeneous overburden. These solutions are critical to interpret the magnetometric resistivity (MMR) data. Our solutions are achieved by solving a boundary value problem in the wave number domain and then transforming back to the spatial domain. The propagator matrix techniques are used. The curves of magnetic field are plotted to show the behavior of the field while some parameters are given approximately. To determine the conductivity parameter, the inverse problem is introduced via the use of optimization technique.