3-D Magnetotelluric Adaptive Finite-Element Modeling

摘要

Aiming at three principal problems existing in traditional node-based finite-element method when modeling MT problems, this paper proposed an adaptive vector-based finite-element method with unstructured mesh. On the basis of 3-D finite-element formulae, it introduces a residual-based posteriori error estimator. Then, it presents the adaptive refinement strategy and computation flow. The test of a homogenous earth model and two anomalies with high resistivity model show that the numerical solutions enable the convergence to the exact results with a maximal average error less than a percentage value of 1%. Thus, it can be concluded that the h-adaptive vector finite-element method can guarantee the accuracy and efficiency of complicated models, through which its great potential is displayed.