Forward Modeling in ERT Employing Resistor Network - Alternative to Standard Approaches

Abstract

This paper uses an orthogonal resistor network model instead of traditional finite-difference or finite-element methods to explore an alternative approach to forward modeling in Electrical Resistivity Tomography (ERT). A resistor network is advantageous for modeling high-contrast resistivity environments, particularly in crystalline rock scenarios with thin conductive fractures. The key idea is to represent the resistivity problem as a network of resistors, where each resistor corresponds to a unit cell edge with assigned resistance values. The study compares this approach with existing numerical methods and analytical solutions for 2D conductive dipping faults, showing that the resistor network method produces comparable results for shallow depths while offering better resolution for thin conductive fractures. This study demonstrates that a resistor network can serve as an auxiliary tool for qualitatively assessing the effects of thin conductive fractures in crystalline rock environments or masonry.