Thermal Reactivation of Microfractures and its Potential Impact on Hydraulic-Fracture Efficiency
- Arash Dahi Taleghani (Louisiana State University) | Milad Ahmadi (Louisiana State University) | Wei Wang (Louisiana State University) | Jon E. Olson (University of Texas At Austin)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- October 2014
- Document Type
- Journal Paper
- 761 - 770
- 2014.Society of Petroleum Engineers
- 1.2.3 Rock properties, 3 Production and Well Operations, 2.5.2 Fracturing Materials (Fluids, Proppant), 5.6.4 Drillstem/Well Testing, 3.2.3 Hydraulic Fracturing Design, Implementation and Optimisation, 1.14 Casing and Cementing, 1.6.9 Coring, Fishing, 2.5.1 Fracture design and containment
- microfractures, hydraulic fracturing, natural fractures, thermal stresses
- 6 in the last 30 days
- 572 since 2007
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Core studies have revealed the presence of abundant cemented microfractures in many tight formations. Further independent studies have revealed the opening of some of these microfractures on the wall surface of main hydraulic fractures. In addition, early-production well-testing analysis in some of these cases provides estimates for the hydraulically-induced-fracture surface area, which is much larger than fracture dimensions estimated in fracturing design or provided by the location of microseismic events. Opening of small-sized fractures could be a possible reason for this discrepancy. In this paper, we show to what extent thermal stresses induced by temperature difference between fracturing fluid and formation fluid could provide the driving force to open a portion of these small, cemented natural fractures lying on the surface of hydraulic fractures. Moreover, through combination of stress analysis and empirical fracture-distribution models obtained from outcrops, we calculate the increase of total reservoir/fracture contact surface under the condition of microfracture activation. Our thermoelasticity analysis reveals the effect of the pump rate and temperature of the fracturing fluid on the number of activated microfractures. The results show that the volume of the microfractures varies depending on the length of the microfracture, rock properties, and time. At the end of the paper, through an example, we show that activation of only a small portion of these microfractures can increase the total fracture/formation contact area considerably and, consequently, increase initial production. Reservoir-pressure changes caused by production might partially close or reopen these microcracks during production; hence, the effectiveness of these microfractures could be mainly restricted to the early life of the reservoirs.
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Aydin, A. and Degraff, J.M. 1993. Effect of Thermal Regime on Growth Increment and Spacing of Contraction Joints in Basaltic Lava. J. Geophys. Res. 98 (B4): 6411–6430. http://dx.doi.org/10.1029/92JB01709.
Bai, T. and Pollard, D.D. 2000. Spacing of Fractures in a Multilayer at Fracture Saturation. Int. J. Fracture 100 (4): 23–28. http://dx.doi.org/10.1023/A:1018748026019.
Barr, D.T. 1980. Thermal Cracking in Nonporous Geothermal Reservoirs. MS thesis, Massachusetts Institute of Technology, Cambridge, Massachusetts (1980).
Barenblatt, G.I. 1962. The Mathematical Theory of Equilibrium Cracks in Brittle Fracture. J. Appl. Mech.-T. ASME 7: 55–129.
Batchelor, G.K. 1967. An Introduction to Fluid Dynamics. Cambridge, UK: Cambridge University Press.
Bažant, Z.P. and Cedolin, L. 1991. Stability of Structures: Elastic, Inelastic, Fracture and Damage Theories. New York City, New York: Oxford University Press.
Bažant, Z.P., Ohtsubo, R. and Aoh, K. 1979. Stability and Post-Critical Growth of a System of Cooling and Shrinkage Cracks. Int. J. Fracture 15 (5): 443–456. http://dx.doi.org/10.1007/BF00023331.
Bažant, Z.P, and Planas, J. 1994. Fracture and Size Effect in Concrete and Other Quasibrittle Materials, first edition. Boca Raton, Florida: CRC Press.
Biot, M.A., Masse, L. and Medlin, W.L. 1987. Temperature Analysis in Hydraulic Fracturing. J. Pet. Tech. 39 (11): 1389–1397. http://dx.doi.org/10.2118/13228-PA.
Bonnet, E., Bour, O., Odling, N.E., et al. 2001. Scaling of Fracture Systems in Geological Media. Rev. Geophys. 39 (3): 347–383. http://dx.doi.org/10.1029/1999RG000074.
Charlotte, M., Laverne, J. and Marigo, J. 2006. Initiation of Cracks with Cohesive Force Models: A Variational Approach. Eur. J. Mech. A-Solid. 25 (4): 649–669. http://dx.doi.org/10.1016/j.euromechsol.2006.05.002.
Chen, Z., Bunger, A., Zhang, X., et al. 2009. Cohesive Zone Finite Element-Based Modeling of Hydraulic Fractures. Acta Mech. Solida Sin. 22 (5):443–452. http://dx.doi.org/10.1016/S0894-9166(09)60295-0.
Choi, J.W., Duncan, I.J. and Rodin, G.J. 2012. Microcrack Nucleation in Porous Solids Under Predominantly Compressive Stress States with Applications to Shale Gas Exploration. Oral presentation given at the 46th US Rock Mechanics/Geomechanics Symposium, Chicago, Illinois, 24–27 June.
Clifton, R.J. and Wang, J. J. 1991. Modeling of In-Situ Stress Change Due to Cold Fluid Injection. Paper SPE 22107 presented at the International Arctic Technology Conference, Anchorage, Alaska, 29–31 May. http://dx.doi.org/10.2118/22107-MS.
Dahi Taleghani, A. 2011. Modeling Simultaneous Growth of Multi-branch Hydraulic Fractures. Paper ARMA 11-436 presented at the 45th U.S. Rock Mechanics/Geomechanics Symposium, San Francisco, California, 26-29 June.
Dahi Taleghani, A. and Olson, J.E. 2011. Numerical Modeling of Multistranded-Hydraulic-Fracture Propagation: Accounting for the Interaction Between Induced and Natural Fractures. SPE J. 16 (3): 575–581. http://dx.doi.org/10.2118/124884-PA.
Dahi Taleghani, A. and Olson, J. 2013. How Natural Fractures Could Affect Hydraulic-Fracture Geometry. SPE J. (in press; published online XX). http://dx.doi.org/10.2118/167608-PA.
Elices, M., Guinea, G., Gomez, J., et al. 2002. The Cohesive Zone Model: Advantages, Limitations and Challenges. Eng. Fract. Mech. 69 (2): 137–163. http://dx.doi.org/10.1016/S0013-7944(01)00083-2.
Fakcharoenphol, P., Charoenwongsa, S., Kazemi, H., et al. 2012. The Effect of Water Induced Stress to Enhance Hydrocarbon Recovery in Shale Reservoirs. Paper SPE 158053 presented at SPE Annual Technical Conference, San Antonio, Texas, 8–10 October. http://dx.doi.org/10.2118/158053-MS.
Finnie, I., Cooper, G.A. and Berlie, J. 1979. Fracture Propagation in Rock by Transient Cooling. Int. J. Rock Mech. Min. 16 (1): 11–21. http://dx.doi.org/10.1016/0148-9062(79)90771-X.
Jeffrey, R., Zhang, X. and Thiercelin, M. 2009. Hydraulic Fracture Offsetting in Naturally Fractures Reservoirs: Quantifying a Long-Recognized Process. Paper SPE 119351 presented at the SPE Hydraulic Fracturing Technology Conference, The Woodlands, Texas, 19–21 January. http://dx.doi.org/10.2118/119351-MS.
Gale, J.F.W., Reed, R.M. and Holder, J. 2007. Natural Fractures in the Barnett Shale and Their Importance for Hydraulic Fracture Treatments. AAPG Bull. 91 (4): 603–622. http://dx.doi.org/10.1306/11010606061.
Gale, J. F. and Holder, J. 2008. Natural Fractures in Shales: Origins, Characteristics and Relevance for Hydraulic Fracture Treatments. Proc., AAPG 2008 Annual Convention and Exhibition, San Antonio, Texas, Vol. 17, 63.
Hill, R. 1998. The Mathematical Theory of Plasticity, Vol. 11. New York City, New York: Oxford University Press.
Hillerborg, A., Modeer, M. and Petersson, P. 1976. Analysis of Crack Formation and Crack Growth in Concrete by Means of Fracture Mechanics and Finite Elements. Cement Concrete Res. 6 (6): 773–781. http://dx.doi.org/10.1016/0008-8846(76)90007-7.
Loucks, R. G. and Ruppel, S. C. 2007. Depositional Setting and Lithofacies of the Mississippian Deepwater Barnett Shale in the Fort Worth Basin, Texas. AAPG Bull. 91 (4): 579–602. http://dx.doi.org/10.1306/11020606059.
Marrett, R., Ortega, O.J. and Kelsey, C.M. 1999. Extent of Power-Law Scaling for Natural Fractures in Rock. Geology 27 (9): 799–802. http://dx.doi.org/10.1130/0091-7613(1999)027<0799:EOPLSF>2.3.CO;2.
Nemat-Nasser, S., Keer, L.M. and Parihar, K.S. 1978. Unstable Growth of Thermally Induced Interacting Cracks in Brittle Solids. Int. J. Solids Struct. 14 (6): 409–430. http://dx.doi.org/10.1016/0020-7683(78)90007-0.
Ortega, O. and Marrett, R. 2000. Prediction of Macrofracture Properties Using Microfracture Information, Mesaverde Group Sandstones, San Juan Basin, New Mexico. J. Struct. Geol. 22 (5): http://dx.doi.org/10.1016/S0191-8141(99)00186-8.571–588.
Ortega, O. J., Marrett, R. and Laubach, S.E. 2006. A Scale-Independent Approach to Fracture Intensity and Average Fracture Spacing. AAPG Bull. 90 (2): 193–208. http://dx.doi.org/10.1306/08250505059.
Papanastasiou, P.C. 1997. A Coupled Elastoplastic Hydraulic Fracturing Model. Int. J. Rock Mech. Min. 34 (3–4): 240.e1–240.e15. http://dx.doi.org/10.1016/S1365-1609(97)00132-9.
Papanastasiou, P.C. and Thiercelin, M. 1993. Influence of Inelastic Rock Behaviour in Hydraulic Fracturing. Int. J. Rock Mech. Min. 30 (7): 1241–1247. http://dx.doi.org/10.1016/0148-9062(93)90102-J.
Perkins, T. K. and Gonzales, J.A. 1985. The Effect of Thermoelastic Stresses on Injection Well Fracturing. SPE J. 25 (1): 77–88. http://dx.doi.org/10.2118/11332-PA.
Rehbinder, G. 1995. Analytical Solutions of Stationary Coupled Thermo-Hydro-Mechanical Problems. Int. J. Rock Mech. Min. 32 (5): 453–463. http://dx.doi.org/10.1016/0148-9062(95)00035-F.
Rijken, P. 2005. Modeling Naturally Fractured Reservoirs: From Experimental Rock Mechanics to Flow Simulation. PhD dissertation, The University of Texas at Austin, Austin, Texas (2005).
Sarris, E. and Papanastasiou, P. 2011. The Influence of the Cohesive Process Zone in Hydraulic Fracturing Modelling. Int. J. Fracture 167 (1): 33–45. http://dx.doi.org/10.1007/s10704-010-9515-4.
Serra, E. and Bonaldi, M. 2009. A Finite Element Formulation for Thermoelastic Damping Analysis. Int. J. Numer. Meth. Eng. 78 (6): 671–691. http://dx.doi.org/10.1002/nme.2502.
Simo, J. C., and Hughes, T. J. R. 2008. Computational Inelasticity. New York City, New York: Springer-Verlag.
Tao, D. 1983. Finite Element Analysis of Dynamic Coupled Thermoelasticity Problems With Relaxation Times. J. Appl. Mech.-T. ASME 50 (4a): 817–822. http://dx.doi.org/10.1115/1.3167151.
Tvergaard, V. and Hutchinson, J.W. 1996. Effect of Strain-Dependent Cohesive Zone Model on Predictions of Crack Growth Resistance. Int. J. Solids Struct. 33 (20–22): 3297–3308. http://dx.doi.org/10.1016/0020-7683(95)00261-8.
Wang, H. 2000. Theory of Linear Poroelasticity with Applications to Geomechanics and Hydrogeology. Princeton, New Jersey: Princeton University Press.
Warpinski, N. R., Mayerhofer, M. J., Vincent, M. C., et al. 2009. Stimulating Unconventional Reservoirs: Maximizing Network Growth While Optimizing Fracture Conductivity. J. Cdn. Pet. Tech. 48 (10): 39–51. http://dx.doi.org/10.2118/114173-PA.
Zhou, X., Aydin, A., Liu, F., et al. 2010. Numerical Modeling of Secondary Thermal Fractures in Hot Dry Geothermal Reservoirs. Oral presentation given at the 35th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, 1–3 February.