Geomechanical Characterization of Inclined Heterolithic Stratification Lithosome and Its Permeability Evolution under SAGD Stress Paths
- Masoud Khademi (University of Alberta) | Rick Chalaturnyk (University of Alberta)
- Document ID
- Society of Petroleum Engineers
- SPE Annual Technical Conference and Exhibition, 30 September - 2 October, Calgary, Alberta, Canada
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- Permeability, SAGD, Inclined Heterolithic Stratification (IHS), Constitutive Behavior, Triaxial cell
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- 174 since 2007
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A sizeable portion of the Athabasca oil sand reservoir is classified as Inclined Heterolithic Stratification lithosomes (IHSs). However, due to the significant heterogeneity of IHSs and the minimal experimental studies on them, their hydro-geomechanical properties are relatively unknown. The main objectives of this study are investigating the geomechanical constitutive behavior of IHSs and linking their geological and mechanical characteristics to their hydraulic behavior to estimate the permeability evolution of IHSs during a Steam Assisted Gravity Drainage (SAGD) operation. To that end, a detailed methodology for reconstitution of analog IHS specimens was developed, and a microscopic comparative study was conducted between analog and in situ IHS samples. The SAGD-induced stress paths were experimentally simulated by running isotropic cyclic consolidation and drained triaxial shearing tests on analog IHSs. Both series of experiments were performed in conjunction with permeability tests at different strain levels, flow rates, and stress states. Additionally, an analog sample with bioturbation was tested to examine the hydro-geomechanical effects of bioturbation. Finally, the hydro-mechanical characteristics of analog IHS were compared with its constituent layers (sand and mud).
The microscopic study showed that the layers’ integration and grain size distribution are similar in analog and in-situ IHS specimens. The results also revealed that geomechanical properties of IHSs, such as shear strength, bulk compressibility, Young's modulus, and dilation angle, are stress state dependent. In other words, elevating confining pressure could significantly increase the strength and elastic modulus of a sample, while decreasing the compressibility and dilation angle. In contrast, the friction angle and Poisson's ratio are not very sensitive to changes in the isotropic confining stress. An important finding of this study is that the effect of an IHS sample's volume change on permeability is contingent on the stress state and stress path. Volume change during isotropic unloading-reloading resulted in permeability increases and sample dilation during compression shearing resulted in permeability decreases, especially at high effective confining stresses. Moreover, the tests revealed that the existence of bioturbation dramatically improves permeability of IHSs in comparison to equivalent non-bioturbated specimens but has negligible effects on its mechanical properties, which remain similar to non-bioturbated specimens. The results also showed that bioturbation has minimal impact on permeability changes during shearing. Lastly, experimental correlations were developed for each of the parameters mentioned above.
For the first time, specialized experimental protocols have been developed that guide the infrastructure and processes required to reconstitute analog IHS specimens and conduct geomechanical testing on them. This study also delivered fundamental constitutive data to better understand the geomechanical behavior of IHS reservoir and its permeability evolution during the in-situ recovery processes. Such data can be used to accurately capture the reservoir behavior and increase the efficiency of SAGD operations in IHS reservoirs.
|File Size||4 MB||Number of Pages||36|
Byrne, P. M., H. Cheung, and L. Yan. 1987. "Soil parameters for deformation analysis of sand masses." Canadian Geotechnical Journal 24 (3): 366-376. doi:https://doi.org/10.1139/t87-047.
Dahl, Mark B., John R. Suter, Stephen M. Hubbard, and Dale A. Leckie. 2010. "Impact of Inclined Heterolithic Stratification on Oil Sands Reservoir Delineation and Management: An Outcrop Analog from the Late Cretaceous Horseshoe Canyon Formation, Willow Creek, Alberta." GeoCanada 2010 - Working with the Earth. Calgary: Geological Association of Canada.
Government of Alberta. 2017. Oil Sand Facts and Statistics. Accessed May 2017, 4. https://www.alberta.ca/about-oil-sands.aspx.
Gu, F., M. Chan, and R. Fryke. 2011. "Geomechanical Data Acquisition, Monitoring and Applications in SAGD." Journal of Canadian Petroleum Technology (Society of Petroleum Engineers) 50 (06). doi:https://doi.org/10.2118/145402-PA.
Jablonski, Bryce, and Robert Dalrymple. 2016. "Recognition of strong seasonality and climatic cyclicity in an ancient, fluvially dominated, tidally influenced point bar: Middle McMurray Formation, Lower Steepbank River, Lower Steepbank River." International Association of Sedimentologists 552-585.
Ranger, Michael J., and S. George Pemberton. 1992. The sedimentology and Ichnology of estuarine point bars in the McMurray Formation of the Athabasca Oil Sands deposit, northeastern Alberta, Canada. A Core Workshop, SEPM Society for Sedimentary Geology, 401-421. doi:https://doi.org/10.2110/cor.92.01.0401.
Ranger, Michael J., S. George Pemberton, and Curtis D. Lettley. 2012. "The Sedimentology and Ichnology of Estuarine Point Bars in The McMurray Formation of Athabasca Oil Sand Deposits, Northeastern Alberta, Canada. Applications of Ichnology to Petroleum Exploration." Applications of Ichnology to Petroleum Exploration (Society for Sedimentary Geology (SEPM)) 401-415.
Siiro, Petri. 2002. Characteristic grain-size distribution patterns of tidally-influenced coastal plain estuarine sediments based on comparative studies of Cretaceous McMurray Formation in Alberta, Canada and the Miocene Pebas/Solimoes formation in Western Amazonia, Peru. Master's thesis, Turku, Finland: University of Turku.
Strobl, Rudy S., Daryl M. Wightman, Walid K. Muwais, Darrell K. Cotterill, and Liping Yuan. 1997. "Application of Outcrop Analogues and Detailed Reservoir Characterization to the AOSTRA Underground Test Facility, McMurray Formation, North Eastern Alberta." Canadian Society of Petroleum Geologist 18: 375-391.
Tortike, W. S., and S. M. Farouq Ali. 1991. "Prediction of oil sand failure due to steam-induced stresses." Journal of Canadian Petroleum Technology 30 (01): 87-96. doi:https://doi.org/10.2118/91-01-08.
Wang, Shuying, Ronaldo Luna, and Richard W. Stephenson. 2011. "A Slurry Consolidation Approach to Reconstitute Low-Plasticity Silt Specimens for Laboratory Triaxial Testing." Geotechnical Testing Journal 34 (No. 4): 288-296. doi:https://doi.org/10.1520/GTJ103529.