A High-Order FEM Solution for a Time-Domain Electromagnetic Geophysical Forward Solver: Preliminary Results

In this paper, we present a high-order finite element method (FEM) solution for time-domain electromagnetic (TDEM) forward modeling, optimized for geophysical applications. The solver utilizes unstructured tetrahedral meshes and Gaussian-distributed current sources instead of conventional point sources, improving numerical accuracy and reducing mesh refinement requirements. The method employs higher-order basis functions to achieve accurate transient responses with fewer degrees of freedom, enhancing computational efficiency. A variable time-stepping scheme is implemented to balance accuracy and performance, achieving convergence within an error threshold 3% compared to analytical solutions.