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

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.