RESIP2DMODE: A MATLAB-Based 2D Resistivity and Induced Polarization Forward Modeling Software

Forward modeling is an integral part of every geophysical modeling resulting in the numerical simulation of responses for a given physical property model. This Forward procedure is helpful in geophysics both as a means to interpret data in a research setting and as a means to enhance physical understanding in an educational setting. Calculation of resistivity and induced polarization forward responses is carried out using simulation of the current flow into the earth’s surface through solving the Poisson’s equation. In this contribution, a finite-difference algorithm is applied to discretize the simulated models restricted by a mixed boundary condition. To account for the 3D source characteristic, a spatial Fourier transform of the partial differential equations with respect to a range of wave numbers is performed along the strike direction. Then, an inverse Fourier transformation is conducted to obtain the potential solutions in the spatial domain. The present package provides a user-friendly interface designed to understand and handle for various conventional electrical configurations in the frame of the MATLAB programming language. To verify the program, initial responses of some simple models are compared with those of analytic solutions, which proved satisfactory in terms of accuracy. For further evaluation, the code is also examined on some complicated models.