A parallel tool for numerical approximation of 3D electromagnetic surveys in geophysics

Abstract

This paper presents an edge-based parallel code for the data computation that arises when applying one of the most popular electromagnetic methods in geophysics, namely, the controlled-source electromagnetic method (CSEM). The computational implementation is based on the linear Edge Finite Element Method in 3D isotropic domains because it has the ability to eliminate spurious solutions and is claimed to yield accurate results. The framework structure is able to exploit the embarrassingly-parallel tasks and the advantages of the geometric flexibility as well as to work with three different orientations for the dipole, or excitation source, on unstructured tetrahedral meshes in order to represent complex geological bodies through a local refinement technique. We demonstrate the performance and accuracy of our tool on the Marenostrum supercomputer (Barcelona Supercomputing Center) through scaling tests and canonical tests, respectively.