Transient-Rate Analysis of Stress-Sensitive Hydraulic Fractures: Considering the Geomechanical Effect in Anisotropic Shale
- Shanshan Yao (University of Regina) | Xiangzeng Wang (Shaanxi Yanchang Petroleum Group Limited) | Qingwang Yuan (Stanford University) | Fanhua Zeng (University of Regina)
- Document ID
- Society of Petroleum Engineers
- SPE Reservoir Evaluation & Engineering
- Publication Date
- November 2018
- Document Type
- Journal Paper
- 863 - 888
- 2018.Society of Petroleum Engineers
- Stress-sensitive Hydraulic Fractures, Geomechanics, Transient Rate Analysis, Shale Anisotropy
- 3 in the last 30 days
- 207 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 12.00|
|SPE Non-Member Price:||USD 35.00|
Production from multistage-fractured horizontal wells (MFHWs) in shale reservoirs causes stress changes that further influence the conductivities of hydraulic fractures. Moreover, many shale rocks are strongly anisotropic. The objective of this study is to semianalytically model hydrocarbon-flow dynamics in reservoirs with MFHWs. The effects of stress-sensitive hydraulic fractures and shale anisotropy are considered.
First, this study explores the relationship between principal-stress and pore-pressure changes in anisotropic shale. Second, an exponential correlation is further incorporated to describe the fracture conductivities vs. pore-pressure changes in anisotropic shale. The exponential correlation is validated by matching experimental data of fracture conductivities vs. effective stress. The fracture compressibility df in the exponential equation is stress-dependent rather than constant. Next, this study discretizes each hydraulic fracture into several source segments. For each segment in each timestep, pressure distribution is calculated with source/sink functions. Both the stress field and the hydraulic-fracture conductivities are updated according to the pressure distribution with the previously mentioned correlations before starting the next timestep.
In addition to the constant-bottomhole-flowing-pressure condition, nonconstant bottomhole pressure (BHP) in real-field cases can also be entered for this semianalytical model. The model is validated by comparing its results with numerical simulations. A series of type curves q vs. t is generated on the basis of model calculations. The type curves are applied to investigate the effects of initial fracture conductivity Fci, initial fracture compressibility dfi, declining rate of fracture compressibility ß, shale anisotropy, and the BHP profiles on MFHW transient-rate behavior. To maximize the hydrocarbon production, the BHP profile must be adjusted on the basis of fracture stress-sensitive characteristics. The semianalytical model is used to analyze two field cases with different pwf profiles under the influence of stress-sensitive hydraulic fractures.
|File Size||1 MB||Number of Pages||26|
Abass, H., Sierra, L., and Tahini, A. 2009. Optimizing Proppant Conductivity and Number of Hydraulic Fractures in Tight Gas Sand Wells. Presented at the SPE Saudi Arabia Section Technical Symposium, Al-Khobar, Saudi Arabia, 9–11 May. SPE-126159-MS. https://doi.org/10.2118/126159-MS.
An, C., Fang, Y., Liu, S. et al. 2017. Impacts of Matrix Shrinkage and Stress Changes on Permeability and Gas Production of Organic-Rich Shale Reservoirs. Presented at the SPE Reservoir Characterization and Simulation Conference and Exhibition, Abu Dhabi, 8–10 May. SPE-186029-MS. https://doi.org/10.2118/186029-MS.
Aybar, U., Eshkalak, M. O., Sepehrnoori, K. et al. 2014. The Effect of Natural Fracture’s Closure on Long-Term Gas Production From Unconventional Resources. Journal of Natural Gas Science and Engineering 21: 1205–1213. https://doi.org/10.1016/j.jngse.2014.09.030.
Aybar, U., Yu, W., Eshkalak, M. et al. 2015. Evaluation of Production Losses From Unconventional Shale Reservoirs. Journal of Natural Gas Science and Engineering 23: 509–516. https://doi.org/10.1016/j.jngse.2015.02.030.
Brown, M., Ozkan, E., Raghavan, R. et al. 2011. Practical Solutions for Pressure-Transient Responses of Fractured Horizontal Wells in Unconventional Shale Reservoirs. SPE Res Eval & Eng 14 (6): 663–676. SPE-125043-PA. https://doi.org/10.2118/125043-PA.
Celis, V., Silva, R., Ramones, M. et al. 1994. A New Model for Pressure Transient Analysis in Stress Sensitive Naturally Fractured Reservoirs. SPE Advanced Technology Series 2 (1): 126–135. SPE-23668-PA. https://doi.org/10.2118/23668-PA.
Chang, C. and Zoback, M. D. 2009. Viscous Creep in Room-Dried Unconsolidated Gulf of Mexico Shale (a): Experimental Results. J. Pet. Sci. Eng. 69 (3): 239–246. https://doi.org/10.1016/j.petrol.2009.08.018.
Chen, F., Pan, Z., and Ye, Z. 2015. Dependence of Gas Shale Fracture Permeability on Effective Stress and Reservoir Pressure: Model Match and Insights. Fuel 139: 383–392. https://doi.org/10.1016/j.fuel.2014.09018.
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.
Clarkson, C. R. 2013. Production Data Analysis of Unconventional Gas Wells: Workflow. International Journal of Coal Geology 109110:147–157. https://doi.org/10.1016/j.coal.2012.11.016.
Clarkson, C. R., Qanbari, F., Nobakht, M. et al. 2013. Incorporating Geomechanical Changes Into Rate Transient Analysis: Example From the Haynesville Shale. SPE Res Eval & Eng 16 (3): 303–316. SPE-162526-PA. https://doi.org/10.2118/162526-PA.
Dadmohammadi, Y., Misra, S., Sondergeld, C. H. et al. 2016. Improved Petrophysical Interpretation of Laboratory Pressure-Step-Decay Measurements on Ultra-Tight Rock Samples. Presented at the SPE/AAPG/SEG Unconventional Resources Technology Conference, San Antonio, Texas, 1–3 August. URTEC-2441857-MS. https://doi.org/10.15530/URTEC-2016-2441857-MS.
Dadmohammadi, Y., Misra, S., Sondergeld, C. H. et al. 2017. Petrophysical Interpretation of Laboratory Pressure-Step-Decay Measurements on Ultratight Rock Samples. Part 2—In the Presence of Gas Slippage, Transitional Flow, and Diffusion Mechanisms. J. Petroleum Science and Eng. 158: 554–569. https://doi.org/10.1016/j.petrol.2017.08.077.
Dean, R. H., Gai, X., Stone, C. M. et al. 2006. A Comparison of Techniques for Coupling Porous Flow and Geomechanics. SPE J. 11 (1): 132–140. SPE-79709-PA. https://doi.org/10.2118/79709-PA.
Dudley, J. W., Myers, M. T., Shew, R. D. et al. 1998. Measuring Compaction and Compressibilities in Unconsolidated Reservoir Materials by Time-Scaling Creep. SPE Res Eval & Eng 1 (5): 430–437. SPE-51324-PA. https://doi.org/10.2118/51324-PA.
Eshkalak, M. O., Aybar, U., and Sepehrnoori, K. 2014. An Integrated Reservoir Model for Unconventional Resources, Coupling Pressure-Dependent Phenomena. Presented at the SPE Eastern Regional Meeting, Charleston, West Virginia, 21–23 October. SPE-171008-MS. https://doi.org/10.2118/171008-MS.
Friedel, T., Mtchedlishvili, G., Behr, A. et al. 2007. Comparative Analysis of Damage Mechanisms in Fractured Gas Wells. Presented at the SPE European Formation Damage Conference, Scheveningen, The Netherlands, 30 May–1 June. SPE-107662-MS. https://doi.org/10.2118/107662-MS.
Hardage, B., deAngelo, M., and Sava, D. 2011. Marcellus Shale Geophysics. Presentation at the Research Partnership to Secure Energy for America Meeting, Bureau of Economic Geology, University of Texas at Austin, 20 April.
Jones, Jr. F. O. 1975. A Laboratory Study of the Effects of Confining Pressure on Fracture Flow and Storage Capacity in Carbonate Rocks. J Pet Technol 27 (1): 21–27. SPE-4569-PA. https://doi.org/10.2118/4569-PA.
Jones, S. C. 1988. Two-Point Determinations of Permeability and PV vs. Net Confining Stress. SPE Form Eval 3 (1): 235–241. SPE-15380-PA. https://doi.org/10.2118/15380-PA.
Lewis, R. W. and Sukirman, Y. 1993. Finite Element Modeling of Three-Phase Flow in Deforming Saturated Oil Reservoirs. Intl. J. for Num. and Anal. Methods in Geomech. 17 (8): 577–598. https://doi.org/10.1002/nag.1610170804.
Lora, R. V., Ghazanfari, E., and Izquierdo, E. A. 2016. Geomechanical Characterization of Marcellus Shale. Rock Mech. Rock Eng. 49 (9): 3403–3424. https://doi.org/10.1007/s00603-016-0955-7.
McKee, C. R., Bumb, A. C., and Koenig, R. A. 1988. Stress-Dependent Permeability and Porosity of Coal and Other Geologic Formations. SPE Form Eval 3 (1): 81–91. SPE-12858-PA. https://doi.org/10.2118/12858-PA.
Minkoff, S., Stone, C., Bryant, S. et al. 2003. Coupled Fluid Flow and Geomechanical Deformation Modeling. Journal of Petroleum Science and Eng. 38 (1–2): 37–56. https://doi.org/10.1016/S0920-4105(03)00021-4.
Misra, S., Lüling, M. G., Rasmus, J. et al. 2016. Dielectric Effects in Pyrite-Rich Clays on Multifrequency Induction Logs and Equivalent Laboratory Core Measurements. Presented at the SPWLA 57th Annual Logging Symposium, Reykjavik, Iceland, 25–29 June. SPWLA-2016-Z.
Moinfar, A., Sepehrnoori, K., Johns, R. T. et al. 2013. Coupled Geomechanics and Flow Simulation for an Embedded Discrete Fracture Model. Presented at the SPE Reservoir Simulation Symposium, The Woodlands, Texas, 18–20 February. SPE-163666-MS. https://doi.org/10.2118/163666-MS.
Mokhtari, M., Honarpour, M. M., Tutuncu, A. N. et al. 2016. Characterization of Elastic Anisotropy in Eagle Ford Shale: Impact of Heterogeneity and Measurement Scale. SPE Res Eval & Eng 19 (3): 429–439. SPE-170707-PA. https://doi.org/10.2118/170707-PA.
Nobakht, M., Clarkson, C. R., and Kaviani, D. 2012. New and Improved Methods for Performing Rate-Transient Analysis of Shale Gas Reservoirs. SPE Res Eval & Eng 15 (3): 335–350. SPE-147869-PA. https://doi.org/10.2118/147869-PA.
Ostensen, R. W. 1986. The Effect of Stress-Dependent Permeability on Gas Production and Well Testing. SPE Form Eval 1 (3): 227–235. SPE-11220-PA. https://doi.org/10.2118/11220-PA.
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, SPE-106301-MS. https://doi.org/10.2118/106301-MS.
Pedrosa, Jr. O. A. 1986. Pressure Transient Response in Stress Sensitive Formations. Presented at the SPE California Regional Meeting, Oakland, California, 2–4 April. SPE-15115-MS. https://doi.org/10.2118/15115-MS.
Poe, Jr. B. D. 2000. Evaluation of Reservoir and Hydraulic Fracture Properties in Geopressure Reservoirs. Presented at the SPE International Oil and Gas Conference and Exhibition, Beijing, 7–10 November. SPE-64732-MS. https://doi.org/10.2118/64732-MS.
Raghavan, R., Scorer, J. D. T., and Miller, F. G. 1972. An Investigation by Numerical Methods of the Effect of Pressure-Dependent Rock and Fluid Properties on Well Flow Tests. SPE J. 12 (3): 267–275. SPE-2617-PA. https://doi.org/10.2118/2617-PA.
Raghavan, R. and Chin, L. Y. 2004. Productivity Changes in Reservoirs With Stress-Dependent Permeability. SPE Res Eval & Eng 7 (4): 308–315. SPE-88870-PA. https://doi.org/10.2118/88870-PA.
Rice, J. R. and Cleary, M. P. 1976. Some Basic Stress Diffusion Solutions for Fluid-Saturated Elastic Porous Media With Compressible Constituents. In Reviews of Geophysics and Space Physics 14 (2): 227–241. https://doi.org/10.1029/RG014i002p00227.
Riley, K. F., Hobson, M. P., and Bence, S. J. 2010. Mathematical Methods for Physics and Engineering, third edition. Cambridge University Press, p. 455.
Rosen, R., Mickelson, W., Sharf-Aldin, M. et al. 2014. Impact of Experimental Studies on Unconventional Reservoir Mechanisms. Presented at the SPE Unconventional Resources Conference, The Woodlands, Texas, 1–3 April. SPE-168965-MS. https://doi.org/10.2118/168965-MS.
Rudnicki, J. W. 1985. Effect of Pore Fluid Diffusion on Deformation and Failure of Rock. In Mechanics of Geomaterials. John Wiley & Sons Ltd., pp. 315–347.
Rutqvist, J., Wu, Y. S., Tsang, C. F. et al. 2002. A Modeling Approach for Analysis of Coupled Multiphase Fluid-Flow Heat Transfer and Deformation in Fractured Porous Rock. International Journal of Rock Mechanics & Mining Sciences 39: 429–442. https://doi.org/10.1016/S1365-1609(02)00022-9.
Sayers, C. M. 1995. Simplified Anisotropy Parameters for Transversely Isotropic Sedimentary Rocks. Geophysics 60 (6): 1933–1935. https://doi.org/10.1190/1.1443925.
Sayers, C. M. 2013. The Effect of Kerogen on the Elastic Anisotropy of Organic-Rich Shales. Geophysics 78 (2): 65–74. https://doi.org/10.1190/GEO2012-0309.1.
Serra, K., Reynolds, A. C., and Raghavan, R. 1983. New Pressure Transient Analysis Methods for Naturally Fractured Reservoirs. J Pet Technol 35 (12): 2271–2283. SPE-10780-PA. https://doi.org/10.2118/10780-PA.
Settari, A. and Mourits, F. M. 1994. Coupling of Geomechanics and Reservoir Simulation Models. Computational Methods and Advances in Geomechanics 3: 2151–2158.
Settari, A. and Walters, D. A. 2001. Advances in Coupled Geomechanical and Reservoir Modeling With Applications to Reservoir Compaction. SPE J. 6 (3): 334–342. SPE-74142-PA. https://doi.org/10.2118/74142-PA.
Shelley, R., Shah, K., Guliyev, N. et al. 2015. Is Pumping Large-Volume Sand Frac Treatments Sustainable? Presented at the SPE Annual Technical Conference and Exhibition, Houston, 28–30 September. SPE-174863-MS. https://doi.org/10.2118/174863-MS.
Sondergeld, C. H. and Rai, C. S. 2011. Elastic Anisotropy of Shales. The Leading Edge 30: 324–331. https://doi.org/10.1190/1.3567246.
Sone, H. and Zoback, M. D. 2014. Time-Dependent Deformation of Shale Gas Reservoir Rocks and Its Long-Term Effect on the In-Situ State of Stress. International Journal of Rock Mechanics & Mining Sciences 69: 120–132. https://doi.org/10.1016/j.ijrmms.2014.04.002.
Tabatabaie, S. H., Pooladi-Darvish, M., and Matter, L. 2015. Drawdown Management Leads to Better Productivity in Reservoirs With Pressure-Dependent Permeability—or Does It? Presented at the SPE/CSUR Unconventional Resources, Calgary, 20–22 October. SPE-175938-MS. https://doi.org/10.2118/175938-MS.
Tabatabaie, S. H., Pooladi-Darvish, M., Mattar, L. et al. 2016. Analytical Modeling of Linear Flow in Pressure-Sensitive Formations. SPE Res Eval & Eng 20 (1): 215–227. SPE-181755-PA. https://doi.org/10.2118/181755-PA.
Vairogs, J., Hearn, C. L., Dareing, D. W. et al. 1971. Effect of Rock Stress on Gas Production From Low-Permeability Reservoirs. J Pet Technol 23 (9): 1161–1167. SPE-3001-PA. https://doi.org/10.2118/3001-PA.
Van Kruysdijk, C. P. J. W. 1988. Semi-Analytical Modeling of Pressure Transients in Fractured Reservoirs. Presented at the 63rd SPE Annual Technical Conference and Exhibition, Houston, 2–5 October. SPE-18169-MS. https://doi.org/10.2118/18169-MS.
Vernik, L. and Nur, A. 1992. Ultrasonic Velocity and Anisotropy of Hydrocarbon Source Rocks. Geophysics 57 (5): 727–735. https://doi.org/10.1190/1.1443286.
Vernik, L. and Landis, C. 1996. Elastic Anisotropy of Source Rocks: Implications for Hydrocarbon Generation and Primary Migration. AAPG Bull. 80 (4): 531–544.
Vernik, L. and Liu, X. 1997. Velocity Anisotropy in Shales: A Petrophysical Study. Geophysics 62 (2): 521–532. https://doi.org/10.1190/1.1444162.
Wang, C., Wu, Y., Xiong, Y. et al. 2015. Geomechanics Coupling Simulation of Fracture Closure and Its Influence on Gas Production in Shale Gas Reservoirs. Presented at the SPE Reservoir Simulation Symposium, Houston, 23–25 February. SPE-173222-MS. https://doi.org/10.2118/173222-MS.
Wang, H. 2014. Performance of Multiple Fractured Horizontal Wells in Shale Gas Reservoirs With Consideration of Multiple Mechanisms. Journal of Hydrology 510: 299–312. https://doi.org/10.1016/j.jhydrol.2013.12.019.
Wang, J., Jia, A., Wei, Y. et al. Y. 2017. Approximate Semi-Analytical Modeling of Transient Behavior of Horizontal Well Intercepted by Multiple Pressure-Dependent Conductivity Fractures in Pressure-Sensitive Reservoir. Journal of Petroleum Science and Engineering 153: 157–177. https://doi.org/10.1016/j.petrol.2017.03.032.
Weaver, J. D., Rickman, R. D., and Luo, H. 2010. Fracture-Conductivity Loss Caused by Geochemical Interactions Between Man-Made Proppants and Formations. SPE J. 15 (1): 116–124. SPE-118174-PA. https://doi.org/10.2118/118174-PA.
Yao, S., Zeng, F., Liu, H. et al. 2013. A Semianalytical Model for Multistage Fractured Horizontal Wells. Journal of Hydrology 507: 201–212. https://doi.org/10.1016/j.jhydrol.2013.10.033.
Yao, S., Zeng, F. and Liu, H. 2016. A Semianalytical Model for Hydraulically Fractured Horizontal Wells With Stress-Sensitive Conductivities. Environ. Earth Sci. 75: 34. https://doi.org/10.1007/s12665-015-4775-y.
Zeng, F. 2008. Modeling of Non-Darcy Flow in Porous Media and Its Application. Dissertation, University of Regina (March 2008).
Zhang, J., Kamenov, A., Zhu, 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.
Zimmerman, R. W., Somerton, W. H., and King, M. S. 1986. Compressibility of Porous Rocks. J. Geophys. Res: Solid Earth 91 (B12): 12765–12777. https://doi.org/10.1029/JB091iB12p12765.