New Insights on Mechanisms Controlling Fracturing-Fluid Distribution and Their Effects on Well Performance in Shale-Gas Reservoirs
- Yongzan Liu (University of Alberta) | Juliana Yuk Leung (University of Alberta) | Richard J. Chalaturnyk (University of Alberta) | Claudio Juan José Virues (Nexen Energy)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- August 2019
- Document Type
- Journal Paper
- 564 - 585
- 2019.Society of Petroleum Engineers
- geomechanical simulation, Horn River Shale gas reservoir, production analysis, flow simulation
- 5 in the last 30 days
- 532 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 5.00|
|SPE Non-Member Price:||USD 35.00|
Many stimulated shale-gas wells experience surprisingly low fracturing-fluid recoveries. Fracture closure, gravity segregation, proppant distribution, and shut-in (soaking) time have been widely postulated to be the contributing factors. This study examines the effects of these factors on fracturing-fluid distribution and subsequent well performance using flow and geomechanical simulations. In the end, two real-field examples are used to validate the findings in this study.
Geomechanical simulation is used to capture the complex post-closure fracture geometry caused by nonuniform proppant distribution. The geometry is then passed into a series of 3D numerical flow models that are constructed using petrophysical parameters, fluid properties, and operational constraints representative of the Horn River shale-gas reservoir. Within the flow simulation, the hydraulic fracture is represented explicitly in the computational domain by means of local-grid refinement, and the physical process of fracture closure during shut-in and production periods is modeled by adjusting the fracture volume and fracture conductivity dynamically. Non-Darcy behavior caused by high gas velocity in the fracture and matrix desorption are considered. The results of the geomechanical simulation confirm the formation of a residual opening above the proppant pack in a partially propped fracture. The residual opening offers a highly conductive flow path for the gas, which is much more mobile than the water-based fracturing fluid, and this difference in mobility further aggravates gravity segregation. Gravity segregation might lead to water accumulating near the bottom of a vertical planar fracture, but reduced fracture conductivity could limit the segregation and promote a more uniform fluid distribution. Water uptake into the matrix is influenced by forced and spontaneous imbibition caused by the large pressure differential across the matrix/ fracture interface and matrix capillarity. Additional water is displaced into the matrix as pressure depletes and the fracture closes. Fracturing-fluid-penetration depth increases with shut-in time, resulting in an enhancement in the initial gas rate, but lower late-time production is also observed.
Analysis of the residual opening of a partially propped fracture and its role in fracturing-fluid distribution in three dimensions is novel. Field examples suggest that considering the various physical mechanisms investigated in this study could improve the accuracy of the numerical model for history matching and the reliability of the ensuing production forecasting. The findings in this study might provide a better understanding of fracturing-fluid distribution, which is useful for optimizing production strategies and operations concerning hydraulically fractured shale-gas reservoirs.
|File Size||2 MB||Number of Pages||22|
Abbasi, M. A., Ezulike, D. O., Dehghanpour, H. et al. 2014. A Comparative Study of Flowback Rate and Pressure Transient Behavior in Multifractured Horizontal Wells Completed in Tight Gas and Oil Reservoirs. J. Nat. Gas Sci. Eng. 17 (March): 82–93. https://doi.org/10.1016/j.jngse.2013.12.007.
Agrawal, S. and Sharma, M. M. 2015. Practical Insights Into Liquid Loading Within Hydraulic Fractures and Potential Unconventional Gas Reservoir Optimization Strategies. J. Unconven. Oil Gas Resour. 11 (September): 60–74. https://doi.org/10.1016/j.juogr.2015.04.001.
Alkouh, A., McKetta, S., and Wattenbarger, R. A. 2014. Estimation of Effective-Fracture Volume Using Water-Flowback and Production Data for Shale-Gas Wells. J Can Pet Technol 53 (5): 290–303. SPE-166279-PA. https://doi.org/10.2118/166279-PA.
Alotaibi, M. A. and Miskimins, J. L. 2017. Slickwater Proppant Transport in Hydraulic Fractures: New Experimental Findings and Scalable Correlation. SPE Prod & Oper 33 (2): 164–178. SPE-174828-PA. https://doi.org/10.2118/174828-PA.
Alramahi, B. and Sundberg, M. I. 2012. Proppant Embedment and Conductivity of Hydraulic Fractures in Shales. Presented at the 46th US Rock Mechanics/Geomechanics Symposium, Chicago, 24–27 June. ARMA-2012-291.
Anderson, D. M., Turco, F., Virues, C. J. J. et al. 2013. Application of Rate Transient Analysis Workflow in Unconventional Reservoirs: Horn River Shale Gas Case Study. Presented at the SPE Unconventional Resources Conference and Exhibition—Asia Pacific, Brisbane, Australia, 11–13 November. SPE-167042-MS. https://doi.org/10.2118/167042-MS.
Bear, J. 1972. Dynamics of Fluids in Porous Media. New York City: Courier Corporation.
Bertoncello, A., Wallace, J., Blyton, C. et al. 2014. Imbibition and Water Blockage in Unconventional Reservoirs: Well-Management Implications During Flowback and Early Production. SPE Res Eval & Eng 17 (4): 497–506. SPE-167698-PA. https://doi.org/10.2118/167698-PA.
Bradley, H. B. ed. 1992. Petroleum Engineering Handbook, third edition. Richardson, Texas: Society of Petroleum Engineers.
Chen, D., Pan, Z., and Ye, Z. 2015. Dependence of Gas Shale Fracture Permeability on Effective Stress and Reservoir Pressure: Model Match and Insights. Fuel 139 (1 January): 383–392. https://doi.org/10.1016/j.fuel.2014.09.018.
Cheng, Y. 2012. Impact of Water Dynamics in Fractures on the Performance of Hydraulically Fractured Wells in Gas-Shale Reservoirs. J Can Pet Technol 51 (2): 143–151. SPE-127863-PA. https://doi.org/10.2118/127863-PA.
Cho, Y., Ozkan, E., and Apaydin, O. G. 2013. Pressure-Dependent Natural-Fracture Permeability in Shale and Its Effect on Shale-Gas Well Production. SPE Res Eval & Eng 16 (2): 216–228. SPE-159801-PA. https://doi.org/10.2118/159801-PA.
Chou, Q., Gao, H. J., and Somerwil, M. 2011. Analysis of Geomechanical Data for Horn River Basin Gas Shales, North-East British Columbia, Canada. Presented at the SPE Middle East Unconventional Gas Conference and Exhibition, Muscat, Oman, 31 January–2 February. SPE-142498-MS. https://doi.org/10.2118/142498-MS.
Cipolla, C. L., Lolon, E., Mayerhofer, M. J. et al. 2009. The Effect of Proppant Distribution and Un-Propped Fracture Conductivity on Well Performance in Unconventional Gas Reservoirs. Presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, Texas, 19–21 January. SPE-119368-MS. https://doi.org/10.2118/119368-MS.
Clark, P. E. and Quadir, J. A. 1981. Prop Transport in Hydraulic Fractures: A Critical Review of Particle Settling Velocity Equations. Presented at the SPE/DOE Low Permeability Gas Reservoirs Symposium, Denver, 27–29 May. SPE-9866-MS. https://doi.org/10.2118/9866-MS.
Clarkson, C. R., Qanbari, F., and Williams-Kovacs, J. D. 2016. Semi-Analytical Model for Matching Flowback and Early-Time Production of Multi-Fractured Horizontal Tight Oil Wells. J. Unconven. Oil Gas Resour. 15 (September): 134–145. https://doi.org/10.1016/j.juogr.2016.07.002.
Computer Modelling Group (CMG). 2015. GEM: Compositional & Unconventional Reservoir Simulator User’s Guide, Version 2015. Calgary: CMG.
Evans, R. D. and Civan, F. 1994. Characterization of Non-Darcy Multiphase Flow in Petroleum Bearing Formation. Technical Report No. DOE/BC/14659-7, School of Petroleum and Geological Engineering, University of Oklahoma, Norman, Oklahoma (April 1994).
Ezulike, O., Dehghanpour, H., Virues, C. et al. 2016. Flowback Fracture Closure: A Key Factor for Estimating Effective Pore Volume. SPE Res Eval & Eng 19 (4): 567–582. SPE-175143-PA. https://doi.org/10.2118/175143-PA.
Fakcharoenphol, P., Torcuk, M. A., Wallace, J. et al. 2013. Managing Shut-In Time To Enhance Gas Flow Rate in Hydraulic Fractured Shale Reservoirs: A Simulation Study. Presented at the SPE Annual Technical Conference and Exhibition, New Orleans, 30 September–2 October. SPE-166098-MS. https://doi.org/10.2118/166098-MS.
Fan, L., Thompson, J. W., and Robinson, J. R. 2010. Understanding Gas Production Mechanism and Effectiveness of Well Stimulation in the Haynesville Shale Through Reservoir Simulation. Presented at the Canadian Unconventional Resources and International Petroleum Conference, Calgary, 19–21 October. SPE-136696-MS. https://doi.org/10.2118/136696-MS.
Fredd, C. N., McConnell, S. B., Boney, C. L. et al. 2001. Experimental Study of Fracture Conductivity for Water-Fracturing and Conventional Fracturing Applications. SPE J. 6 (3): 288–298. SPE-74138-PA. https://doi.org/10.2118/74138-PA.
Fu, Y., Dehghanpour, H., Ezulike, D. O. et al. 2017. Estimating Effective Fracture Pore Volume From Flowback Data and Evaluating its Relationship to Design Parameters of Multistage-Fracture Completion. SPE Prod & Oper 32 (4): 423–439. SPE-175892-PA. https://doi.org/10.2118/175892-PA.
Gdanski, R. D. and Walters, H. G. 2010. Impact of Fracture Conductivity and Matrix Relative Permeability on Load Recovery. Presented at the SPE Annual Technical Conference and Exhibition, Florence, Italy, 19–22 September. SPE-133057-MS. https://doi.org/10.2118/133057-MS.
Gdanski, R. D., Fulton, D. D., and Shen, C. 2009. Fracture-Face-Skin Evolution During Cleanup. SPE Prod & Oper 24 (1): 22–34. SPE-101083-PA. https://doi.org/10.2118/101083-PA.
Ghanizadeh, A., Clarkson, C. R., Deglint, H. et al. 2016. Unpropped/Propped Fracture Permeability and Proppant Embedment Evaluation: A Rigorous Core-Analysis/Imaging Methodology. Presented at the SPE/AAPG/SEG Unconventional Resources Technology Conference, San Antonio, Texas, 1–3 August. URTEC-2459818-MS. https://doi.org/10.15530/URTEC-2016-2459818.
Hu, X., Wu, K., Li, G. et al. 2018. Effect of Proppant Addition Schedule on the Proppant Distribution in a Straight Fracture for Slickwater Treatment. J Pet Sci Eng 167: 110–119.
Holditch, S. A. 1979. Factors Affecting Water Blocking and Gas Flow From Hydraulically Fractured Gas Wells. J Pet Technol 31 (12): 1515–1524. SPE-7561-PA. https://doi.org/10.2118/7561-PA.
Huo, D., Li, B., and Benson, S. M. 2014. Investigating Aperture-Based Stress-Dependent Permeability and Capillary Pressure in Rock Fractures. Presented at the SPE Annual Technical Conference and Exhibition, Amsterdam, 27–29 October. SPE-170819-MS. https://doi.org/10.2118/170819-MS.
Itasca. 2015. FLAC: Two-Dimensional Explicit Finite Difference Program User’s Guide, Version 7.0. Minneapolis, Minnesota: Itasca Limited.
Jia, P., Cheng, L., Clarkson, C. R. et al. 2017. Flow Behavior Analysis of Two-Phase (Gas/Water) Flowback and Early-Time Production From Hydraulically Fractured Shale-Gas Wells Using a Hybrid Numerical/Analytical Model. Int. J. Coal Geol. 182 (1 September): 14–31. https://doi.org/10.1016/j.coal.2017.09.001.
Kam, P., Nadeem, M., Novlesky, A. et al. 2015. Reservoir Characterization and History Matching of the Horn River Shale: An Integrated Geoscience and Reservoir-Simulation Approach. J Can Pet Technol 54 (6): 475–488. SPE-171611-PA. https://doi.org/10.2118/171611-PA.
Krajcinovic, D. and Lemaitre, J. ed. 1987. Continuum Damage Mechanics: Theory and Applications. CSIM Courses and Lectures, No. 295, International Centre for Mechanical Sciences. New York City: Springer-Verlag.
Lake, L. W. 1989. Enhanced Oil Recovery. Englewood Cliffs, New Jersey: Prentice Hall.
Leverett, M. C. 1941. Capillary Behavior in Porous Solids. Trans. AIME 142 (1): 152–169. SPE-941152-G. https://doi.org/10.2118/941152-G.
Liu, Y., Leung, J. Y., and Chalaturnyk, R. J. 2018. Geomechanical Simulation of Partially Propped Fracture Closure and Its Implication for Water Flow-back and Gas Production. SPE Res Eval & Eng 21 (2): 273–290. SPE-189454-PA. https://doi.org/10.2118/189454-PA.
Long, G., and Xu, G. 2017. The Effects of Perforation Erosion on Practical Hydraulic-Fracturing Applications. SPE J. 22 (2): 645–659. SPE-185173-PA. https://doi.org/10.2118/185173-PA.
Mack, M., Maxwell, S. C., and Lee, B. T. 2016. Microseismic Geomechanical Optimization of Hydraulic Fracturing in the Horn River Basin. Presented at the SPE/AAPG/SEG Unconventional Resources Technology Conference, San Antonio, Texas, 1–3 August. URTEC-2430012-MS. https://doi.org/10.15530/URTEC-2016-2430012.
Manchanda, R., Bryant, E. C., Bhardwaj, P. et al. 2017. Strategies for Effective Stimulation of Multiple Perforation Clusters in Horizontal Wells. SPE Prod & Oper 33 (3): 539–556. SPE-179126-PA. https://doi.org/10.2118/179126-PA.
Nejadi, S., Leung, J. Y., Trivedi, J. J. et al. 2015. Integrated Characterization of Hydraulically Fractured Shale-Gas Reservoirs—Production History Matching. SPE Res Eval & Eng 18 (4): 481–494. SPE-171664-PA. https://doi.org/10.2118/171664-PA.
Novlesky, A., Kumar, A., and Merkle, S. 2011. Shale Gas Modeling Workflow: From Microseismic to Simulation—A Horn River Case Study. Presented at the Canadian Unconventional Resources Conference, Calgary, 15–17 November. SPE-148710-MS. https://doi.org/10.2118/148710-MS.
Pagels, M., Hinkel, J. J., and Willberg, D. M. 2012. Measuring Capillary Pressure Tells More Than Pretty Pictures. Presented at the SPE International Symposium and Exhibition on Formation Damage Control, Lafayette, Louisiana, 15–17 February. SPE-151729-MS. https://doi.org/10.2118/ 151729-MS.
Palisch, T. T., Duenckel, R. J., Bazan, L. W. et al. 2007. Determining Realistic Fracture Conductivity and Understanding Its Impact on Well Performance—Theory and Field Examples. Presented at the SPE Hydraulic Fracturing Technology Conference, College Station, Texas, 29–31 January. SPE- 106301-MS. https://doi.org/10.2118/106301-MS.
Palisch, T. T., Vincent, M., and Handren, P. J. 2010. Slickwater Fracturing: Food for Thought. SPE Prod & Oper 25 (3): 327–344. SPE-115766-PA. https://doi.org/10.2118/115766-PA.
Parmar, J., Dehghanpour, H., and Kuru, E. 2012. Unstable Displacement: A Missing Factor in Fracturing Fluid Recovery. Presented at the SPE Canadian Unconventional Resources Conference, Calgary, 30 October–1 November. SPE-162649-MS. https://doi.org/10.2118/162649-MS.
Parmar, J., Kuru, E., and Dehghanpour, H. 2013. Drainage Against Gravity: Factors Impacting the Load Recovery in Fractures. Presented at the SPE Unconventional Resources Conference, The Woodlands, Texas, 10–12 April. SPE-164530-MS. https://doi.org/10.2118/164530-MS.
Patankar, N. A., Joseph, D. D., Wang, J. et al. 2002. Power Law Correlations for Sediment Transport in Pressure Driven Channel Flows. Int. J. Multi- phas. Flow 28 (8): 1269–1292. https://doi.org/S0301-9322(02)00030-7.
Shah, S. N., Mahmoud, A., and Lord, D. L. 2001. Proppant Transport Characterization of Hydraulic-Fracturing Fluids Using a High-Pressure Simulator Integrated With a Fiber-Optic/Light-Emitting-Diode (LED) Vision System. SPE Prod & Fac 16 (1): 42–49. SPE-69210-PA. https://doi.org/10.2118/69210-PA.
Sharma, M. and Agrawal, S. 2013. Impact of Liquid Loading in Hydraulic Fractures on Well Productivity. Presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, Texas, 4–6 February. SPE-163837-MS. https://doi.org/10.2118/163837-MS.
Shiozawa, S. and McClure, M. 2016. Simulation of Proppant Transport With Gravitational Settling and Fracture Closure in a Three-Dimensional Hydraulic Fracturing Simulator. J. Pet. Sci. Eng. 138 (February): 298–314. https://doi.org/10.1016/j.petrol.2016.01.002.
Sierra, L., Sahai, R. R., and Mayerhofer, M. J. 2014. Quantification of Proppant Distribution Effect on Well Productivity and Recovery Factor of Hydraulically Fractured Unconventional Reservoirs. Presented at the SPE/CSUR Unconventional Resources Conference–Canada, Calgary, 30 September–2 October. SPE-171594-MS. https://doi.org/10.2118/171594-MS.
Sun, J. and Schechter, D. 2015. Investigating the Effect of Improved Fracture Conductivity on Production Performance of Hydraulically Fractured Wells: Field-Case Studies and Numerical Simulations. J Can Pet Technol 54 (6): 442–449. SPE-169866-PA. https://doi.org/10.2118/169866-PA.
Wang, H. Y. and Sharma, M. M. 2018. Modeling of Hydraulic Fracture Closure on Proppants With Proppant Settling. J. Pet. Sci. Eng. 171 (December): 636–645. https://doi.org/10.1016/j.petrol.2018.07.067.
Wang, J. and Elsworth, D. 2018. Role of Proppant Distribution on the Evolution of Hydraulic Fracture Conductivity. J. Pet. Sci. Eng. 166 (July): 249–262. https://doi.org/10.1016/j.petrol.2018.03.040.
Wang, M. and Leung, J. Y. 2015. Numerical Investigation of Fluid-Loss Mechanisms During Hydraulic Fracturing Flowback Operations in Tight Reservoirs. J. Pet. Sci. Eng. 133 (September): 85–102. https://doi.org/10.1016/j.petrol.2015.05.013.
Wang, M. and Leung, J. Y. 2016. Numerical Investigation of Coupling Multiphase Flow and Geomechanical Effects on Water Loss During Hydraulic-Fracturing Flowback Operation. SPE Res Eval & Eng 19 (3): 520–537. SPE-178618-PA. https://doi.org/10.2118/178618-PA.
Wang, Y. and Aryana, S. 2016. Numerical Investigation of Stress-Dependent Fracture Apertures and Their Spatial Variations on Production From Unconventional Gas Reservoirs With Complex Fracture Geometries. Presented at the SPE Low Perm Symposium, Denver, 5–6 May. SPE-180244-MS. https://doi.org/10.2118/180244-MS.
Warpinski, N. R. 2010. Stress Amplification and Arch Dimensions in Proppant Beds Deposited by Waterfracs. SPE Prod & Oper 25 (4): 461–471. SPE-119350-PA. https://doi.org/10.2118/119350-PA.
Wheaton, B., Miskimins, J., Wood, D. et al. 2014. Integration of Distributed Temperature and Distributed Acoustic Survey Results With Hydraulic Fracture Modeling: A Case Study in the Woodford Shale. Presented at the Unconventional Resources Technology Conference, Denver, 25–27 August. URTEC-1922140-MS. https://doi.org/10.15530/URTEC-2014-1922140.
Witherspoon, P. A., Wang, J. S. Y., Iwai, K. et al. 1980. Validity of Cubic Law for Fluid Flow in a Deformable Rock Fracture. Water Resour. Res. 16 (6): 1016–1024. https://doi.org/10.1029/WR016i006p01016.
Wu, K. and Olson, J. E. 2016. Mechanisms of Simultaneous Hydraulic-Fracture Propagation From Multiple Perforation Clusters in Horizontal Wells. SPE J. 21 (3): 1000–1008. SPE-178925-PA. https://doi.org/10.2118/178925-PA.
Wu, K., Olson, J., Balhoff, M. T. et al. 2016. Numerical Analysis for Promoting Uniform Development of Simultaneous Multiple-Fracture Propagation in Horizontal Wells. SPE Prod & Oper 32 (1): 41–50. SPE-174869-PA. https://doi.org/10.2118/174869-PA.
Xu, Y., Adefidipe, O., and Dehghanpour, H. 2016. A Flowing Material Balance Equation for Two-Phase Flowback Analysis. J. Pet. Sci. Eng. 142 (June): 170–185. https://doi.org/10.1016/j.petrol.2016.01.018.
Yang, R., Huang, Z., Li, G. et al. 2017. A Semianalytical Approach to Model Two-Phase Flowback of Shale-Gas Wells With Complex-Fracture-Network Geometries. SPE J. 22 (6): 1808–1833. SPE-181766-PA. https://doi.org/10.2118/181766-PA.
Yu, W., Luo, Z., Javadpour, F. et al. 2014. Sensitivity Analysis of Hydraulic Fracture Geometry in Shale-Gas Reservoirs. J. Pet. Sci. Eng. 113 (January): 1–7. https://doi.org/10.1016/j.petrol.2013.12.005.
Yu, W., Zhang, T., Du, S. et al. 2015. Numerical Study of the Effect of Uneven Proppant Distribution Between Multiple Fractures on Shale-Gas Well Performance. Fuel 142 (15 February): 189–198. https://doi.org/10.1016/j.fuel.2014.10.074.
Yuan, B., Wood, D. A., and Yu, W. 2015. Stimulation and Hydraulic Fracturing Technology in Natural Gas Reservoirs: Theory and Case Studies (2012–2015). J. Nat. Gas Sci. Eng. 26 (September): 1414–1421. https://doi.org/10.1016/j.jngse.2015.09.001.
Yuan, B., Xu, C., Wang, K. et al. 2017. Enhance Horizontal Well Performance by Optimising Multistage Hydraulic Fracture and Water Flooding. Int. J. Oil Gas Coal Technol. 15 (1): 25–46. https://doi.org/10.1504/IJOGCT.2017.083857.
Yue, M., Leung, J. Y., and Dehghanpour, H. 2016. Numerical Investigation of Limitations and Assumptions of Analytical Transient Flow Models in Tight Oil Reservoirs. J. Nat. Gas Sci. Eng. 30 (March): 471–486. https://doi.org/10.1016/j.jngse.2016.01.042.
Zanganeh, B., Soroush, M., Williams-Kovacs, J. D. et al. 2015. Parameters Affecting Load Recovery and Oil Breakthrough Time After Hydraulic Fracturing in Tight Oil Wells. Presented at the SPE/CSUR Unconventional Resources Conference, Calgary, 20–22 October. SPE-175941-MS. https://doi.org/10.2118/175941-MS.
Zhang, J., Kamenov, A., Hill, A. D. et al. 2014. Laboratory Measurement of Hydraulic-Fracture Conductivities in the Barnett Shale. SPE Prod & Oper 29 (3): 216–227. SPE-163839-PA. https://doi.org/10.2118/163839-PA.
Zhang, X., Jeffrey, R. G., Bunger, A. P. et al. 2011. Initiation and Growth of a Hydraulic Fracture From a Circular Wellbore. Int. J. Rock Mech. & Mining Sci. 48 (6): 984–995. https://doi.org/10.1016/j.ijrmms.2011.06.005.