Numerical simulation of a single fracture with various parameters.
Hydraulic fracturing is the process of enhancing host rock permeability through injection of pressurized fluid in order to obtain oil and natural gas. Typically, microseismicity is used during the fracturing process to monitor the fractures, but this technique fails to describe the degree of fracture connectivity. In this study, the direct current resistivity (DCR) survey method is modeled for fractures with varying lengths, asymmetry, and orientation in order to determine whether DCR can go beyond detection and discriminate fractures based on these parameters. Three different host rock resistivities are used and fracture resistivity is held constant at 0.25 ohm-m. Results indicate that the contrast between host rock and fracture resistivity determines whether a fracture can be detected, and that additional boreholes aid in discerning fractures of different lengths and asymmetric fractures. Additionally, DCR provides the most information about fractures in highly resistive host rocks (>100 ohm-m).