9:30 AM - 9:45 AM
[SCG61-15] Fluid-Flow, Resistivity and Elastic Wave Velocity Simulation of Digital Rock Fracture and Comparison with Experimental Data
Keywords:digital rock physics, elastic wave velocity, resistivity, fracture flow, Lattice Boltzmann Method
We conducted laboratory fluid-flow testby using fractured Inada granite (50 mm in a diameter, 80 mm in a length) which have single tensile fracture with different aperture. For the numerical model, we digitalized this real rock fracture (0.1 mm grid resolution) to calculate fluid-flow, resistivity and elastic wave velocity under the same condition with experiment. Three dimensional fracture flow was simulated by using Lattice Boltzmann Method and we applied Finite Element Analysis to calculate resistivity and elastic wave velocity after this fluid-flow simulation.
As a result, permeability decreases with pressure increase under laboratory experiment and calculated permeability also shows the decrease as the aperture increases. This agreement suggests that fracture permeability is constrained by aperture closure due to the pressure effect. From the permeability matching approach, we found that permeability dramatically decreases after the fracture contact area exceeds ~80%. At this threshold value, fluid-flow path, resistivity and elastic wave velocity show inflections. Our results suggest that permeability change caused by aperture closure could be estimated by seismic and electromagnetic explorations.