High order edge-based finite elements for 3D magnetotelluric modeling with unstructured meshes

Abstract

We present a 3D magnetotelluric (MT) forward modeling program which computes the distribution of the electric field on an unstructured mesh. We employ high order edge elements and implement the Edge Finite Element method to accurately simulate magnetotelluric data in the form of impedance tensor. The program is open-source and optimized for both high-performance computing (HPC) architectures and non-HPC architectures. The paper details the theory, method and code work-flow. We evaluate the accuracy of our algorithm with various synthetic test models and compare our results with other Finite Element (FE) and Finite Difference (FD) algorithms. The experiments show that the implemented high order elements are effective in providing highly accurate solutions for multiple frequencies with few elements independently of the model’s geometry. Hence, leading to reduced computing times.