Mechanically Induced Fracture-Face Skin--Insights From Laboratory Testing and Modeling Approaches
- Andreas Reinicke (GFZ German Research Centre for Geosciences) | Guido Blöcher (GFZ German Research Centre for Geosciences) | Günter Zimmermann (GFZ German Research Centre for Geosciences) | Ernst Huenges (GFZ German Research Centre for Geosciences) | Georg Dresen (GFZ German Research Centre for Geosciences) | Sergei Stanchits (TerraTek) | Björn A. Legarth (Royal Dutch Shell) | Axel Makurat (Royal Dutch Shell)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- October 2012
- Document Type
- Journal Paper
- 26 - 35
- 2012. Society of Petroleum Engineers
- 3 Production and Well Operations, 1.8 Formation Damage, 2.5.2 Fracturing Materials (Fluids, Proppant)
- 4 in the last 30 days
- 596 since 2007
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In the context of this work, a new formation-damage mechanism is proposed--the mechanically induced fracture-face skin (FFS). This new mechanism results from mechanical interactions between the proppants and the reservoir rock caused by the increasing stress on the rock/proppant system during production. Proppant embedment into the fracture face and proppant crushing lead to fines production and may impair the fracture performance. To achieve sustainable, long-term productivity from a reservoir, it is indispensable to understand the hydraulic and mechanical interactions in rock/proppant systems. In this study, permeability measurements on sandstones with propped fractures under stress using various flow cells were performed, allowing localization and quantification of the mechanical damage at the fracture face. The laboratory experiments identified a permeability reduction at the fracture face of up to 90%. The mechanical damage at the rock/proppant interface began immediately with loading of the rock/proppant system and for fracture-closure stresses less than 35 MPa; the damage was localized at the fracture face. Microstructure analysis identified quartz-grain crushing, fines production, and pore-space blocking at the fracture face, causing the observed mechanically induced FFS. At higher stresses, damage and embedment of the ceramic proppants reduce the fracture permeability further. Numerical modeling of the rock/proppant system identified highly inhomogeneous stress distributions in the granular system of grains and proppants. High tensile-stress concentrations beneath the area of contact between quartz grains and proppants were observed, even at small differential stress applied to the rock/proppant system. These high-stress concentrations were responsible for the early onset of damage at the fracture face. Therefore, even low differential stresses, which are expected under in-situ conditions, may affect the productivity of a hydraulically fractured well.
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Al-Abduwani, F.A.H., Shirazadi, A., van den Broek, W.M.G.T. et al. 2003.Formation Damage vs. Solid Particles Deposition Profile During LaboratorySimulated PWRI. Paper SPE 82235 presented at the SPE European Formation DamageConference, The Hague, 13-14 May. http://dx.doi.org/10.2118/82235-MS.
Anderson, R.W., Cooke Jr., C.E., and Wendorff, C.L. 1989. Propping Agentsand Fracture Conductivity. In Recent Advances in Hydraulic Fracturing,ed. J.L. Gidley, S.A. Holditch, D.E. Nierode, and R.W. Veatch Jr., Vol. 12,Chap. 6, 109-130. Richardson, Texas: Henry L. Doherty Monograph Series,SPE.
Azarov, A., Radkowski, D., and Baron, R. 2007. Modeling of Filter CloggingDuring Suspension Filtering. Paper presented at the COMSOL Conference 2007,Boston, Massachusetts, USA, 4-6 October.
Behr, A., Mtchedlishvili, G., Friedel, T. et al. 2003. Consideration ofDamaged Zone in Tight Gas Reservoir Model with Hydraulically Fractured Well.Paper SPE 82298 presented at the SPE European Formation Damage Conference, TheHague, 13-14 May. http://dx.doi.org/10.2118/82298-MS.
Blöcher, G., Bruhn, D., Zimmerman, G. et al. 2007. Investigation of theundrained poroelastic response of sandstones to confining pressure vialaboratory experiment, numerical simulation and analytical calculation. InRock Physics and Geomechanics in the Study of Reservoirs andRepositories, ed. C. David and M. Le Ravalec-Dupin, No. 284. Bath, UK:Special Publication, Geological Society of London.
Cinco-Ley, H. and Samaniego-V., F. 1977. Effect of Wellbore Storage andDamage on the Transient Pressure Behavior of Vertically Fractured Wells. PaperSPE 6752 presented at the SPE Annual Fall Technical Conference and Exhibition,Denver, 9-12 October. http://dx.doi.org/10.2118/6752-MS.
Cinco-Ley, H. and Samaniego-V., F. 1981. Transient Pressure Analysis: FiniteConductivity Fracture Versus Damaged Fracture Case. Paper SPE 10179 presentedat the SPE Annual Technical Conference and Exhibition, San Antonio, Texas, USA,4-7 October. http://dx.doi.org/10.2118/10179-MS.
Cramer, D.D. 2005. Fracture Skin: A Primary Cause of StimulationIneffectivenessas in Gas Wells. Paper SPE 96869 presented at the SPE AnnualTechnical Conference and Exhibition, Dallas, 9-12 October. http://dx.doi.org/10.2118/96869-MS.
Darcy, H.P.G. 1856. Les Fontaines Publiques de la Ville de Dijon ,Appendix--Note D, 647 and Atlas. Paris: Bookseller of the Imperial Corps ofBridges, Highways and Mines.
Economides, M.J. and Nolte, K.G. 2000. Reservoir Stimulation, thirdedition. New York: John Wiley & Sons.
Fredd, C.N., McConnell, S.B., Boney, C.L. et al. 2000. Experimental Study ofHydraulic Fracture Conductivity Demonstrates the Benefits of Using Proppants.Paper SPE 60326 presented at the SPE Rocky Mountain Regional/Low-PermeabilityReservoirs Symposium and Exhibition, Denver, 12-15 March. http://dx.doi.org/10.2118/60326-MS.
Geandier, G., Denis, S., and Mocellin, A. 2003. Float glass fracturetoughness determination by Hertzian contact: experiments and analysis. J.Non-Cryst. Solids 318 (3): 284-295. http://dx.doi.org/10.1016/s0022-3093(02)01886-0.
Geuzaine, C. and Remacle, J.-F. 2006. Gmsh: a three-dimensional finiteelement mesh generator with built-in pre- and post-processing facilities,Version 1.65 (15 May 2006), http://www.geuz.org/gmsh/.
Hertz , H. 1882. Ueber die Berührung fester elastischer Körper (On theContact of Elastic Solids). Journal für die reine und angewandte Mathematik(Crelle's Journal) 1882 (92): 156-171. http://dx.doi.org/10.1515/crll.1882.92.156.
Hiramatsu, Y. and Oka, Y. 1966. Determination of the tensile strength ofrock by a compression test of an irregular test piece. International Journalof Rock Mechanics and Mining Sciences & Geomechanics Abstracts 3 (2): 89-90. http://dx.doi.org/10.1016/0148-9062(66)90002-7.
Hoek, E. and Franklin, J.A. 1968. A simple triaxial cell for field andlaboratory testing of rock. Trans. Instn Min. Metall. 77:Section A, 22-26.
Holditch, S.A. 1979. Factors Affecting Water Blocking and Gas Flow FromHydraulically Fractured Gas Wells. J Pet Technol 31 (12):1515-1524. SPE-7561-PA. http://dx.doi.org/10.2118/7561-PA.
Klein, E. and Reuschlé, T. 2003. A Model for the Mechanical Behaviour ofBentheim Sandstone in the Brittle Regime. Pure Appl. Geophys. 160 (5): 833-849. http://dx.doi.org/10.1007/pl00012568.
Legarth, B.A., Raab, S., and Huenges, E. 2005. Mechanical interactionsbetween proppants and rock and their effect on hydraulic fracture performance.In Vorträge der Frühjahrstagung des DGMK-Fachbereichs,DGMK/ÖGEW-Frühjahrstagung des Fachbereichs Aufsuchung und Gewinnung, Sec4.1, 275-288. Celle, Germany: Erdöl Erdgas Kohle/GFZ Publications.
Lynn, J.D. and Nasr-El-Din, H.A. 1998. Evaluation of formation damage due tofrac stimulation of a Saudi Arabian clastic reservoir. J. Pet. Sci. Eng. 21 (3-4): 179-201. http://dx.doi.org/10.1016/s0920-4105(98)00074-6.
Moghadasi, J., Jamialahmadi, M., Müller-Steinhagen, H. et al. 2002.Formation Damage in Iranian Oil Fields. Presented at the InternationalSymposium and Exhibition on Formation Damage Control, Lafayette, Louisiana,USA, 20-21 February. SPE-73781-MS. http://dx.doi.org/10.2118/73781-MS.
Nasr-El-Din, H.A. 2003. New Mechanisms of Formation Damage: Lab Studies andCase Histories. Presented at the SPE European Formation Damage Conference, TheHague, 13-14 May. SPE-82253-MS. http://dx.doi.org/10.2118/82253-MS.
Reinicke, A. 2010. Mechanical and Hydraulic Aspects of Rock-proppantSystems Laboratory Experiments and Modelling Approaches. PhD dissertation,Universität Potsdam, Potsdam, Germany.
Romero, D.J., Valko, P.P., and Economides, M.J. 2003. Optimization of theProductivity Index and the Fracture Geometry of a Stimulated Well With FractureFace and Choke Skins. SPE Prod & Oper 18 (1): 57-64.SPE-81908-PA. http://dx.doi.org/10.2118/81908-PA.
Schönert, K. 2004. Breakage of spheres and circular discs. PowderTechnol. 143-144 (25 June 2004): 2-18. http://dx.doi.org/10.1016/j.powtec.2004.04.004.
Shackelford, J.F. and Alexander, W. ed. 2001. Periodic Table of Elements inCeramic Materials. In The CRC Materials Science And EngineeringHandbook, third edition, 18. Boca Raton, Florida: CRC Press.
Timoshenko, S. and Goodier, J.N. 1970. Theory of Elasticity, thirdedition. Singapore: McGraw-Hill Education.
Trautwein, U. 2005. Poroelastische Verformung und petrophysikalischeEigenschaften von Rotliegend Sandsteinen. PhD dissertation, TechnischenUniversität Berlin, Berlin, Germany (September 2005).
Wang, H.F. 2000. Theory of Linear Poroelasticity with Applications toGeomechanics and Hydrogeology. Princeton, New Jersey: Princeton UniversityPress.
Wang, W., Kosakowski, G., and Kolditz, O. 2009. A parallel finite elementscheme for thermo-hydro-mechanical (THM) coupled problems in porous media.Comput. Geosci. 35 (8): 1631-1641. http://dx.doi.org/10.1016/j.cageo.2008.07.007.
Warren, P.D. 1995. Determining the fracture toughness of brittle materialsby Hertzian indentation. J. Eur. Ceram. Soc. 15 (3):201-207. http://dx.doi.org/10.1016/0955-2219(95)93941-u.
Wen, Q., Zhang, S., Wang, L. et al. 2007. The effect of proppant embedmentupon the long-term conductivity of fractures. J. Pet. Sci. Eng. 55 (3-4): 221-227. http://dx.doi.org/10.1016/j.petrol.2006.08.010.
Zang, A., Christian Wagner, F., Stanchits, S. et al. 1998. Source analysisof acoustic emissions in Aue granite cores under symmetric and asymmetriccompressive loads. Geophys. J. Int. 135 (3): 1113-1130. http://dx.doi.org/10.1046/j.1365-246X.1998.00706.x.
Zimmermann, G. and Reinicke, A. 2010. Hydraulic stimulation of a deepsandstone reservoir to develop an Enhanced Geothermal System: Laboratory andfield experiments. Geothermics 39 (1): 70-77. http://dx.doi.org/10.1016/j.geothermics.2009.12.003.