Hydraulic properties of 3D crossed rock fractures by considering anisotropic aperture distributions
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Abstract
This study presents a numerical study on the geometrical and hydraulic properties of a three-dimensional intersected fracture model that is a fundamental element involved in complex fracture networks. A series of rough fracture surfaces were generated using the modified successive random additions (SRA) algorithm. Different shear displacements were applied to the fracture to obtain the anisotropic aperture fields that will be further assigned to the two fractures in the intersected fracture model. The flow was calculated using the Reynolds equation with the continuity conditions addressed at intersection part between the two fracture planes. The evolutions of the aperture distributions, flow channels and equivalent permeability were estimated. The simulation results reveal that as the shear displacement and joint roughness coefficient (JRC) increase, the aperture increases anisotropically, which causes significant fluid flow channeling effects. The main flow channels change from being concentrated in one fracture to the other fracture during the shear, accompanied by the change of the flow rate ratios between two flow planes at the inlet/outlet boundary. During the shear the average contact area accounts for approximately 4% to 15% of the fracture planes, and the actual calculated flow area is about 35% to 42% of the fracture planes, which is smaller than the noncontact area. As the shear displacement and JRC increase, the equivalent permeability of the intersected fracture increases. Therefore, the channeling flow should be considered to interpret the fluid flow through the rough fractures even in the simplest fracture networks.
Cited as: Liu, R., Jiang, Y., Huang, N., Sugimoto, S. Hydraulic properties of 3D crossed rock fractures by considering anisotropic aperture distributions. Advances in Geo-Energy Research, 2018, 2(2): 113-121, doi: 10.26804/ager.2018.02.01
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Adler, P.M., Thovert, J.F. Fractures and Fracture Networks. New York, USA, Springer Science & Business Media, 1999.
Auradou, H., Drazer, G., Boschan, A., et al. Flow channeling in a single fracture induced by shear displacement. Geothermics 2006, 35(5-6): 576-588.
Auradou, H., Drazer, G., Hulin, J.P., et al. Permeability anisotropy induced by the shear displacement of rough fracture walls. Water Resour. Res. 2005, 41(9).
Baghbanan, A., Jing, L. Stress effects on permeability in a fractured rock mass with correlated fracture length and aperture. Int. J. Rock Mech. Min. 2008, 45(8): 1320-1334.
Berkowitz, B., Adler, P.M. Stereological analysis of fracture network structure in geological formations. J. Geophys. Res. 1998, 103(B7): 15339-15360.
Cai, J., Wei, W., Hu, X., et al. Fractal characterization of dynamic fracture network extension in porous media. Fractals 2017, 25(2): 1750023.
Crandall, D., Bromhal, G., Karpyn, Z.T. Numerical simula-tions examining the relationship between wall-roughness and fluid flow in rock fractures. Int. J. Rock Mech. Min. Sci. 2010, 47(5): 784-796.
Darcel, C., Bour, O., Davy, P., et al. Connectivity properties of twodimensional fracture networks with stochastic fractal correlation. Water Resour. Res. 2003, 39(10).
Gentier, S., Lamontagne, E., Archambault, G., et al. Anisotropy of flow in a fracture undergoing shear and its relationship to the direction of shearing and injection pressure. Int. J. Rock Mech. Min. Sci. 1997, 34(3-4): 94, e1-94, e12.
Huang, N., Jiang, Y., Liu, R., et al. A predictive model of permeability for fractal-based rough rock fractures during shear. Fractals 2017b, 25(5): 1750051.
Huang, N., Liu, R., Jiang, Y. Numerical study of the geometrical and hydraulic characteristics of 3D selfaffine rough fractures during shear. J. Nat. Gas Sci. Eng. 2017a, 45: 127-142.
Huang, N., Liu, R., Jiang, Y., et al. Effects of fracture surface roughness and shear displacement on geometrical and hydraulic properties of three-dimensional crossed rock fracture models. Adv. Water Resour. 2018, 113: 30-41.
Isakov, E., Ogilvie, S.R., Taylor, C.W., et al. Fluid flow through rough fractures in rocks I: High resolution aperture determinations. Earth Planet. Sci. Lett. 2001, 191(3-4): 267-282.
Jafari, A., Babadagli, T. Relationship between percolationfrac-tal properties and permeability of 2-D fracture networks. Int. J. Rock Mech. Min. 2013, 60: 353-362.
Kim, H.M., Inoue, J. Analytical approach for anisotropic permeability through a single rough rock joint under shear deformation. J. Geophys. Res. 2003, 108(B8). Klimczak, C., Schultz, R.A., Parashar, R., et al. Cubic law with aperture-length correlation: Implications for network scale fluid flow. Hydrogeol. J. 2010, 18(4): 851-862.
Kosakowski, G., Berkowitz, B. Flow pattern variability in natural fracture intersections. Geophys. Res. Lett. 1999, 26(12): 1765-1768.
Latham, J.P., Xiang, J., Belayneh, M., et al. Modelling stress-dependent permeability in fractured rock including effects of propagating and bending fractures. Int. J. Rock Mech. Min. Sci. 2013, 57: 100-112.
Lee, H.S., Cho, T.F. Hydraulic characteristics of rough fractures in linear flow under normal and shear load. Rock Mech. Rock Eng. 2002, 35(4): 299-318.
Li, B., Jiang, Y. Quantitative estimation of fluid flow mechanism in rock fracture taking into account the influences of JRC and Reynolds number. J. MMIJ 2013, 129(7): 479-484.
Li, B., Liu, R., Jiang, Y. Influences of hydraulic gradient, surface roughness, intersecting angle, and scale effect on nonlinear flow behavior at single fracture intersections. J. Hydrol. 2016, 538: 440-453.
Lin, D., Wang, J., Yuan, B., et al. Review on gas flow and recovery in unconventional porous rocks. Adv. Geo-Energy Res. 2017, 1(1): 39-53.
Liu, H.H., Bodvarsson, G.S., Lu, S., et al. A corrected and generalized successive random additions algorithm for simulating fractional Levy motions. Math. Geol. 2004, 36(3): 361-378.
Liu, R., Li, B., Jiang, Y., et al. A numerical approach for assessing effects of shear on equivalent permeability and nonlinear flow characteristics of 2-D fracture networks. Adv. Water Resour. 2018, 111: 289-300.
Matsuki, K., Chida, Y., Sakaguchi, K., et al. Size effect on aperture and permeability of a fracture as estimated in large synthetic fractures. Int. J. Rock Mech. Min. Sci. 2006, 43(5): 726-755.
Neuville, A., Flekkφ y, E.G., Toussaint, R. Influence of asperities on fluid and thermal flow in a fracture: A coupled lattice Boltzmann study. J. Geophys. Res. 2013, 118(7): 3394-3407.
Olsson, W.A., Brown, S.R. Hydromechanical response of a fracture undergoing compression and shear. Int. J. Rock Mech. Min. Sci. 1993, 30(7): 845-851.
Park, Y.J., Dreuzy, J.R., Lee, K.K., et al. Transport and intersection mixing in random fracture networks with power law length distributions. Water Resour. Res. 2001, 37(10): 2493-2501.
Rasouli, V., Hosseinian, A. Correlations developed for estimation of hydraulic parameters of rough fractures through the simulation of JRC flow channels. Rock Mech. Rock Eng. 2011, 44(4): 447-461.
Rong, G., Yang, J., Cheng, L., et al. Laboratory investigation of nonlinear flow characteristics in rough fractures during shear process. J. Hydrol. 2016, 541: 1385-1394.
Sidiq, H., Amin, R., Kennaird, T. The study of relative permeability and residual gas saturation at high pressures and high temperatures. Adv. Geo-Energy Res. 2017, 1(1): 64-68.
Tsang, C.F., Bernier, F., Davies, C. Geohydromechanical processes in the Excavation Damaged Zone in crystalline rock, rock salt, and indurated and plastic clays-in the context of radioactive waste disposal. Int. J. Rock Mech. Min. Sci. 2005, 42(1): 109-125.
Wang, M., Chen, Y.F., Ma, G.W., et al. Influence of surface roughness on nonlinear flow behaviors in 3D self-affine rough fractures: Lattice Boltzmann simulations. Adv. Water Resour. 2016, 96: 373-388.
Wei, W., Xia, Y. Geometrical, fractal and hydraulic properties of fractured reservoirs: A mini-review. Adv. Geo-Energy Res. 2017, 1(1): 31-38.
Wilson, C.R., Witherspoon, P.A. Flow interference effects at fracture intersections. Water Resour. Res. 1976, 12(1): 102-104.
Witherspoon, P.A., Wang, J.S.Y., Iwai, K., et al. Validity of cubic law for fluid flow in a deformable rock fracture. Water Resour. Res. 1980, 16(6): 1016-1024.
Xie, L.Z., Gao, C., Ren, L., et al. Numerical investigation of geometrical and hydraulic properties in a single rock fracture during shear displacement with the Navier-Stokes equations. Environ. Earth Sci. 2015, 73(11): 7061-7074.
Zafarani, A., Detwiler, R.L. An efficient time-domain approach for simulating Pe-dependent transport through fracture intersections. Adv. Water Resour. 2013, 53: 198-207.
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