Abstract
A novel finite-volume approach for complicated 2D magnetotellurics (MT) problems with arbitrarily surface topography is presented. An edge-surface integral balance equation is derived by employing a conservation law on the generalized 2D MT boundary value problem. A triangular grid is used to discretize the 2D conductivity model so that we can deal with arbitrarily complex cases with surface topography. The node-centered finite-volume algorithm is used to derive the final system of linear equations on a dual mesh of the triangular grid, which is solved by a robust direct solver. Three synthetic models verify the accuracy of the presented finite-volume algorithm and its capability of dealing with surface topography.
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Du, HK., Ren, ZY. & Tang, JT. A finite-volume approach for 2D magnetotellurics modeling with arbitrary topographies. Stud Geophys Geod 60, 332–347 (2016). https://doi.org/10.1007/s11200-014-1041-9
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DOI: https://doi.org/10.1007/s11200-014-1041-9