A Special Grid for the Numerical Analysis of the Integral Equation Method in the Magnetotelluric Sounding Problem

被引:0
作者
Barashkov I.S. [1 ]
机构
[1] Laboratory of Mathematical Physics, Faculty of Computational Mathematics and Cybernetics, Lomonosov Moscow State University, Moscow
关键词
electromagnetic sounding; Green’s tensor; integral equation method; nonhomogeneous contrast medium;
D O I
10.1007/s10598-021-09533-y
中图分类号
学科分类号
摘要
The article carries out numerical analysis of the integral-equation method for the magnetotelluric sounding problem in a nonhomogeneous medium. The case of high-contrast conducting media is considered in detail, with a conducting nonhomogeneity embedded in a poorly conducting medium. Numerical analysis of the integral equation in this case shows that the solution has low accuracy if a traditional uniform rectangular grid is superposed on the nonhomogeneity and the electric field is evaluated at nodes traditionally placed at the centers of the grid cells. In this approach, nothing is done to resolve the field behavior at the nonhomogeneity boundary in the belied that the boundary conditions will be satisfied on their own automatically. Even the introduction of enhanced background conductivity does not improve the accuracy. A much better result is obtained when enhanced background conductivity is combined with a special nonuniform grid in which the cells in the top grid row have reduced height and the nodes are placed at the top boundary of these cells. This result is substantiated by allowing for the singularity of the integral equation. © 2021, Springer Science+Business Media, LLC, part of Springer Nature.
引用
收藏
页码:305 / 318
页数:13
相关论文
共 12 条
[1]  
Dmitriev V.I., The integral-equation method in low-frequency electrodynamics of nonhomogeneous contrast, Comput. Math. and Model., 29, pp. 42-47, (2018)
[2]  
Dmitriev V.I., Zakharov E.V., Integral-Equation Method in Computational Electrodynamics, (2008)
[3]  
Dmitriev V.I., Marine Electromagnetic Sounding, (2004)
[4]  
Dmitriev V.I., Belkin P.S., Mershchikova N.A., Integral equation method for modeling of two-dimensional geoelectricity problems, Comput. Math. and Model., 16, pp. 289-300, (2005)
[5]  
Cumaabc M., Gribenkoab A., Zhdanov M.S., Inversion of magnetotelluric data using integral equation approach with variable sensitivity domain: Application to EarthScope MT data, Physics of the Earth and Planetary Interiors, 270, pp. 113-127, (2017)
[6]  
Bello M.A., Guo R., Liu J., Forward plane-wave electromagnetic model in three dimensions using hybrid finite volume-integral equation scheme, Geophysical Prospecting, 67, pp. 2213-2226, (2019)
[7]  
Dmitriev V.I., Barashkov I.S., Mathematical modeling of marine electromagnetic sounding of a three-dimensional nonhomogeneous medium, Comput. Math. and Model., 23, 3, pp. 239-253, (2012)
[8]  
Barashkov I.S., Dmitriev V.I., Modeling marine electromagnetic soundings by the reciprocity principle, Comput. Math. and Model., 24, 1, pp. 1-13, (2013)
[9]  
Dmitriev V.I., Barashkov I.S., Mathematical modeling of mobile marine electromagnetic soundings, Comput. Math. and Model., 25, 3, pp. 342-350, (2014)
[10]  
Dmitriev V.I., Barashkov I.S., Finite-difference–integral method for computing low-frequency electromagnetic fields in a nonhomogeneous medium, Comput. Math. and Model., 27, 2, pp. 145-161, (2016)