Modelling the 3D TDEM response using the 3D full-domain finite-element method based on the hexahedral edge-element technique

A resolution study of buried valleys using laterally constrained inversion of TEM data

“…Arnason (1995), Best et al (1995), Alumbaugh et al (1996) and Sugeng (1998). Full 3D inversion of TEM data is more rare.…”

Three-dimensional finite-element modelling of magnetotelluric data with a divergence correction

“…Vector basis functions with corresponding properties -divergence-free within a cell, continuity of tangential component between cells -can be constructed for general hexahedral and tetrahedral meshes (see, for example, Jin, 2002). Edge elements were first applied to geophysical electromagnetic methods by Sugeng (1998), using a rectilinear mesh. Edge elements are used by Nam et al (2007) for a structured mesh of hexahedral (i.e., distorted brick) elements, and by Börner et al (2008) and Liu et al (2008) for unstructured meshes of tetrahedral elements.…”

Three-dimensional magnetotellurics modeling using edgebased finite-element unstructured meshes

“…In this paper, we introduce a new edge-based FEM using three-dimensional unstructured meshes rather than structured meshes (Nelson., 1998;Nam et al, 2007;Sugeng, 1998;Yoshimura and Oshiman, 2002) to solve 3D MT forward problems. 3D unstructured meshes are a set of tetrahedron elements owning irregular triangles faces and edges which can efficiently approximate the surfaces or curves of geological models and decrease the errors from geometrical discretization.…”

“…By terms of the vector identify formula B · ( Δ ×A)=A · ( Δ ×B)+(A×B) and the Green's integral equation (Sugeng, 1998;Nam et al, 2007), its variation expression can be easily deduced as,…”

“…These problems will lead to loss of accuracy for the numerical solutions. Fortunately, an edge-based fi nite-element method (Sugeng, 1998) for solving the Helmholtz or curl-curl equations can effi ciently avoid these problems.…”