二维非均匀介质中大地电磁响应的计算  

COMPUTATION OF MAGNETOTELLURIC RESPONSE IN THE 2-D INHOMOGENEOUS MEDIA

作　　者：汪功礼[1] 张庚骥[1] 

机构地区：[1]石油大学(华东)资源系测井教研室,山东东营257062

出　　处：《计算物理》2001年第1期47-51,共5页Chinese Journal of Computational Physics

摘　　要：在二维非均匀介质中 ,将大地电磁问题可看作电磁波在有耗开放波导中的传播问题 ,借用研究波导问题的数值模式匹配法予以解决 .在计算Ex型问题时 ,使用Hermite基函数和非均匀元素 ;在计算Hx型问题时 ,使用变型Hermite基函数 .In the 2 D inhomogeneous media, the magnetotelluric problem can be taken as one on propagation of electromagnetic wave in the dissipitive open waveguide, and is attacked with the numerical modematching method(NMM). First, the problem domain is sectioned into several subdomains, in each of which the resistivity changes only along the horizontal direction. Then the governing equation is separated into two differential equations. One equation relates to z variable and has analytical solution, while the other relating to y variable is computed with numerical method. The electromagnetic fields between different subdomains are related through the continuous conditions of the electromagnetic field. While the dimension of the problem is reduced to one, the demand for the computer resources decreases apparently and the speed increases substantially. In order to further improve the efficiency of the algorithm, the Hermite basis functions and the inhomogeneous elements are used in Ex problem, and the modified Hermite basis functions are used in Hx problem. Comparison with the finite element method(FEM) shows that NMM is at least ten times faster than FEM. [

关 键 词：数值模式匹配法 下行波 广义反射阵 广义透射阵 大地电磁响应 二维非均匀介质 

分 类 号：P631.325[天文地球—地质矿产勘探]