关键词: 磁电阻率法, 层状介质, 点电流源, 天然气水合物

Abstract:

The method to compute magnetometric resistivity response of a point current source in a layered medium was introduced. This method was based on rotation formula of the current magnetic field and the magnetic fields can be expressed by a double integration about spatial radial coordinate and spatial wave number of Bessel function. The double integration can be simplified to standard Bessel integration through the relation of Bessel functions. At last a direct numerical integration method is applied to computing the integration, and in this process continued fraction expansion was used to speed up integral summation. With the method, the magnetic fields of seabed gas hydrate model had been computed. The result shows that the existence of seabed gas hydrate can bring obvious changes in magnetic fields.