Numerical simulation of the electrical properties of fractured rock based on digital rock technology

Abstract

A means to construct a 3D fractured digital core using a numerical method is proposed in this paper. The electrical properties of a fractured digital core have been studied based on this model using a finite element method. The results show that the electrical behaviour of a fractured core fully saturated with formation water is not significantly influenced by the presence of a fracture. However, the fracture has great influence on the electrical properties of partially saturated rock, where the fracture and the rock matrix pore form a dual-porosity system. The RI–Sw curve of fractured rock can be divided into two linear segments with different saturation exponents. The simulation results for resistivity anisotropy show that there are significant differences in resistivity for a fully saturated fractured sample measured in different directions. Therefore, the fracture should be considered in defining the saturation exponent.