Design of Caprock Integrity in Thermal Stimulation of Shallow Oil-Sands Reservoirs
- Yanguang Yuan (BitCan G&E Incorporated) | Bin Xu (BitCan G&E Incorporated) | Claes Palmgren (Value Creation Incorporated)
- Document ID
- Society of Petroleum Engineers
- Journal of Canadian Petroleum Technology
- Publication Date
- July 2013
- Document Type
- Journal Paper
- 266 - 278
- 2013. Society of Petroleum Engineers
- 5.8.5 Oil Sand, Oil Shale, Bitumen
- 4 in the last 30 days
- 443 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 10.00|
|SPE Non-Member Price:||USD 30.00|
Stakeholders in in-situ oil-sands development take caprock-integrity issues seriously. The industry is faced with the challenge of determining an optimal operating pressure in the reservoir where, in general, the pressure should stay significantly low to ensure the caprock integrity while being significantly high for enhanced oil production and economics. This paper presents a comprehensive work program on the subject for a shallow oil-sands play. Caprock integrity considers the induced stress and deformation in a caprock during the thermal stimulation of an oil-sands reservoir. A minifrac-test program is undertaken to define the original in-situ stress state. Laboratory tests are carried out to measure the deformation and strength properties. Simulations are run to calculate the induced stresses and evaluate them against the mechanical strength. This paper describes some important quality-control issues for these activities. For the minifrac tests, multiple cycles and use of flowback are promoted for enhanced efficiency and accuracy. Laboratory tests are recommended on whole cores in a drained condition at a slow strain rate. Numerical simulations should use site-specific and laboratory-measured material properties. On the basis of the limited sensitivity analyses, the thermal expansion coefficient of the reservoir and Young's modulus of the caprock are found to significantly affect the caprock deformation and/or induced stresses.
|File Size||1 MB||Number of Pages||13|
Agar, J.G., Morgenstern, N.R., and Scott, J.D. 1986. Thermal expansionand pore pressure generation in oil sands. Canadian Geotechnical Journal 23 (3): 327-333. http://dx.doi.org/10.1139/t86-046.
Bell, J.S., Price, P.R., and Mclellan, P.J. 1994. In-situ Stress inthe Western Canada Sedimentary Basin. In Geological Atlas of the WesternCanada Sedimentary Basin (WCSB), G.D. Mossop and I. Shetsen, Chap. 29.Available online from Alberta Geological Survey, http://www.ags.gov.ab.ca/publications/wcsb_atlas/atlas.html.
Bishop, A.W. 1966. The Strength of Soils as Engineering Materials.Geotechnique 16 (2): 89-130.
Butler, R.M. 1986. The Expansion Of Tar Sands During Thermal Recovery. JCan Pet Technol 25 (5). PETSOC-86-05-05. http://dx.doi.org/10.2118/86-05-05.
Butler, R.M. 1991. Thermal Recovery of Oil and Bitumen. EnglewoodCliffs, New Jersey: Prentice Hall.
Butler, R.M. and Stephens, D.J. 1981. The Gravity Drainage of Steam-HeatedHeavy Oil to Parallel Horizontal Wells. J Can Pet Technol 20 (2): 90-96. JCPT Paper No. 81-02-07. http://dx.doi.org/10.2118/81-02-07.
Chhina, H.S., Luhning, R.W., Bilak, R.A. et al. 1987. A Horizontal FractureTest In The Athabasca Oil Sands. Presented at the 38th Annual Technical Meetingof the Petroleum Society of CIM/SPE Annual Technical Meeting, Calgary, 7-10June. CIM 87-38-56. http://dx.doi.org/10.2118/87-38-56.
Chhina, H.S. and Agar, J.G. 1985. Potential Use of Fracture Technology forRecovery of Bitumen from Oil Sands. Presented at the 3rd InternationalConference on Heavy Crude and Tar Sands, Long Beach, California, USA, 22-31June.
Hudson, J.A., Brown, E.T., Fairhurst, C. et al. 1993. Rock Testing and SiteCharacterization. In Comprehensive Rock Engineering: Principles, Practice& Projects, Vol. 3, Chap. 17-21. Oxford, UK: Pergamon Press.
Kenney, T.C. 1967. The Influence of Mineral Composition on the ResidualShear Strength of Natural Soils. Proc., Geotechnical Conference on ShearStrength Properties of Natural Soils and Rocks, Oslo, Norway, Vol. 1, 123-129,TRB 00237620.
Kry, P.R. 1989. Field Observations of Steam Distribution during Injection tothe Cold Lake Reservoir. In Rock at Great Depth: Rock Mechanics and RockPhysics at Great Depth—Proceedings of an International Symposium, Pau, 28-31August 1989, V. Maury and D. Fourmaintraux, Vol. 3. London: Taylor &Francis.
Kry, P.R., Boone, T.J., Gronseth, J.M. et al. 1992. Fracture OrientationObservations from an Athabasca Oil Sands Cyclic Steam Stimulation Project.Presented at the 43rd Annual Technical Meeting of the Petroleum Society of CIM,Calgary, 7-10 June. CIM 92-37.
Mitchell, J.K. and Soga, K. 2005. Fundamentals of Soil Behavior. NewYork: John Wiley & Sons.
Palmgren, C., Walker, I., Carlson, M. et al. 2011. Reservoir design of ashallow LP-SAGD project for in-situ extraction of Athabasca bitumen.Presented at the 2011 World Heavy Oil Conference (WHOC11), Edmonton, Alberta,Canada, 14-17 March. WHOC11-520.
Proskin, S.A., Scott, J.D., and Chhina, H.S. 1990. Current Practice inthe Interpretation of Microfrac Tests in Oil Sands. Presented at the SPECalifornia Regional Meeting, Ventura, California, USA, 4-6 April. SPE-20040-MS.http://dx.doi.org/10.2118/20040-MS.
Raaen, A.M. and Brudy, M. 2001. Pump-in/Flowback Tests Reduce the Estimateof Horizontal in-Situ Stress Significantly. Presented at the SPE AnnualTechnical Conference and Exhibition, New Orleans, 30 September-3 October.SPE-71367-MS. http://dx.doi.org/10.2118/71367-MS.
Raaen, A.M., Skomedal, E., Kjørholt, H. et al. 2001. Stress determinationfrom hydraulic fracturing tests: the system stiffness approach. Int. J. RockMech. Min. Sci. 38 (4): 529-541. http://dx.doi.org/http://dx.doi.org/10.1016/S1365-1609(01)00020-X.
Settari, A. and Raisbeck, J.M. 1979. Fracture Mechanics Analysis in In-SituOil Sands Recovery. J Can Pet Technol 18 (2): 85-94.PETSOC-79-02-07. http://dx.doi.org/10.2118/79-02-07.
SIMULIA 2012. ABAQUS Version 6.12 documentation, http://www.3ds.com/products/simulia/support/documentation/.
Smith, R.J., Bacon, R.M., Boone, T.J. et al. 2004. Cyclic Steam StimulationBelow a Known Hydraulically Induced Shale Fracture. J Can Pet Technol 43 (2): 39-46. PETSOC-04-02-03. http://dx.doi.org/10.2118/04-02-03.
Xu, B., Yuan, Y.G., and Wang, Z.C. 2011. Thermal Impact On ShaleDeformation/Failure Behaviors --- Laboratory Studies. Presented at the 45th USRock Mechanics/Geomechanics Symposium 2011, San Francisco, California, USA,26-29 June. ARMA-11-303.
Yuan, Y. 2008. Overburden/Casing Integrity in SAGD without High OperatingPressures. Presented at the 2008 Canadian International PetroleumConference/Petroleum Society s 59th Annual Technical Meeting, Calgary, 17-19June. CIPC-2008-206.