多层介质点电流源磁场响应计算  

Computation of Magnetic Fields of Point Current Source in Layered Medium

作　　者：刘云鹤[1] 陈玉玲[1] 翁爱华[1] 

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026

出　　处：《吉林大学学报（地球科学版）》2009年第5期918-922,共5页Journal of Jilin University：Earth Science Edition

基　　金：国家'863'项目(2006AA06Z109);国家自然科学基金项目(40874050)

摘　　要：介绍了点电流源层状介质模型磁电阻率法响应的模拟方法。由电流磁场的旋度公式出发,推导了多层介质中点电流源磁场的表达式,其为一个关于空间径向坐标和贝塞尔函数空间波数的二重积分。利用贝塞尔函数的性质可将该二重积分化为标准的贝塞尔积分,然后采用直接数值积分的方法计算该积分。在此过程中通过连分式展开加快积分求和的收敛速度。利用上述方法对海底天然气水合物模型点电流源产生的磁场进行了计算。模型计算结果表明,海底天然气水合物的存在能引起磁场较为明显的相对变化。The method to compute magnetometrie 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.

关 键 词：磁电阻率法 层状介质 点电流源 天然气水合物 

分 类 号：P631.3[天文地球—地质矿产勘探]