Forward modeling of applied geophysics methods using Comsol and comparison with analytical and laboratory analog models

Forward modeling is useful in geophysics both as a tool to interpret data in a research setting and as a tool to develop physical understanding in an educational setting. Gravity, magnetics, resistivity, and induced polarization are methods used in applied geophysics to probe Earth's subsurface. In this contribution, we present forward models of these geophysical techniques using the finite-element modeling package Comsol. This package allows relatively easy implementation of these models and, as part of the AC/DC module, allows exterior boundaries to be placed at infinity, a boundary condition that is frequently encountered in geophysics. We compare the output of the finite-element calculations with analytical solutions and, for the resistivity method, with laboratory-scale analog experiments and demonstrate that these are in excellent agreement.

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