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 EPE  Vol.7 No.3 , March 2015
Unconventional Shale Reservoir’s Property Estimation through Modeling, Case Studies of Australian Shale
Abstract: A simplified approach is introduced to model production from shale gas resources. In this approach, a multi-fractured horizontal gas well in a shale formation is divided into four zones. Shale formation between each pair of hydraulic fractures consists of four zones: compacted zone around well-bore (1), shale matrix (2), induced fractures (3) and main hydraulic fractures (4). The main contribution of this study is considering varying permeability for each specific zone implemented in the mathematical presentation of gas flow in shale. Further, gas desorption and slippage effect are applied to the model to capture the realistic gas flow in shale. The nonlinear partial differential equation of gas flow obtained from mass conservations law is then solved numerically for each specific zone with respect to their appropriate boundary conditions. This approach then is applied to three case studies, Cooper Basin, Georgina and Galilee shale. A history matching of the mentioned formations is accomplished to find the most uncertain parameters undertaken through this simplified approach. Results of this study are in an agreement with other methods and it is demonstrated that the simplified approach provides more accurate production forecast for the well-established Georgina asset and is in a good agreement for Cooper and Galilee. This study is also valuable since it provides some rough estimation for shale rock characteristics as the basis for rigorous simulation studies.
Cite this paper: Shiver, R. , Nelsen, K. , Li, E. , Lee, J. and Dwithes, G. (2015) Unconventional Shale Reservoir’s Property Estimation through Modeling, Case Studies of Australian Shale. Energy and Power Engineering, 7, 71-80. doi: 10.4236/epe.2015.73007.
References

[1]   Brown, M.L. (2009) Analytical Trilinear Pressure Transient Model for Multiply Fractured Horizontal Wells in Tight Shale Reservors. M.Sc. Thesis, Colorado School of Mines, Golden.

[2]   Aybar, U., Eshkalak, M.O., Sepehrnoori, K. and Patzek, T.W. (2014) Long Term Effect of Natural Fractures Closure on Gas Production from Unconventional Reservoirs. SPE Eastern Regional Meeting 2014, Charleston, 21-23 October 2014, Paper SPE 171010.

[3]   Eshkalak, M.O., Aybar, U. and Sepehrnoori, K. (2014) An Integrated Reservoir Model for Unconventional Resources, Coupling Pressure Dependent Phenomena. Eastern Regional Meeting, Charleston, 21-23 October 2014, Paper SPE 171008.

[4]   Civan, A.F., Devegowda, D. and Sigal, R. (2010) Accurate Simulation of Shale Gas Reservoir. Annual Technical Conference and Ehibition held in Florence, Italy, 19-22 September 2010, Paper SPE 135564.

[5]   Eshkalak, M.O., Mohaghegh, S.D. and Esmaili, S. (2013) Synthetic, Geomechanical Logs for Marcellus Shale. Digital Energy Conference and Exhibition, The Woodlands, 5-7 March 2013, Paper SPE 163690.

[6]   Eshkalak, M.O., Aybar, U. and Sepehrnoori, K. (2014) An Economic Evaluation on the Re-Fracturing Treatment of the US Shale Gas Resources. Eastern Regional Meeting, Charleston, 21-23 October 2014, Paper SPE 171009.

[7]   Eshkalak, M.O., et al. (2014) Simulation Study on the CO2-Driven Enhanced Gas Recovery with Sequestration versus the Re-Fracturing Treatment of Horizontal Wells in the U.S. Unconventional Shale Reservoirs. Journal of Natural Gas Science and Engineering, 21, 1015-1024.
http://dx.doi.org/10.1016/j.jngse.2014.10.013

[8]   Mengal, S.A. and Wattenbarger, R.A. (2011) Accounting for Adsorbed Gas in Shale Gas Reservoirs. SPE Middle East Oil and Gas Show and Conference, Manama, 25-28 September 2011, Paper SPE 141085.
http://dx.doi.org/10.2118/141085-MS

[9]   Langmuir, I. (1918) The Adsorption of Gases on Plane Surfaces of Glass, Mica and Platinum. Journal of the American Chemical Society, 40, 1403-1461.
http://dx.doi.org/10.1021/ja02242a004

[10]   Tao, Q., Ghassemi, A. and Ehlig-Economides, C.A. (2010) Pressure Transient Behavior for Stress-Dependent Fracture Permeability in Naturally Fractured Reservoirs. CPS/SPE International Oil and Gas Conference and Exhibition, 8-10 June 2010, Beijing, SPE 131666.

[11]   Eshkalak, M.O., Al-Shalabi, E.W., Aybar, U. and Sepehrnoori, K. (2014) Enhanced Gas Recovery by CO2 Sequestration versus Re-Fracturing Treatment in Unconventional Shale Gas Reservoirs. Abu Dhabi International Petroleum and Exhibition and Conference, Abu Dhabi, 10-13 November 2014, Paper SPE 172083.

[12]   Omidvar Eshkalak, M. (2013) Synthetic Geomechanical Logs and Distributions for Marcellus Shale. M.Sc. Thesis, West Virginia University, Morgantown.

[13]   Aybar, U. (2014) Investigation of Analytical Models Incorporating Geomechanical Effects on Production Performance of Hydraulically and Naturally Fractured Unconventional Reservoirs. M.Sc. Thesis, The University of Texas at Austin, Austin.

[14]   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 Reservoir Evaluation & Engineering, 16, 216-228.
http://dx.doi.org/10.2118/159801-PA

[15]   Alramahi, B. and Sundberg, M.I. (2012) Proppant Embedment and Conductivity of Hydraulic Fractures in Shales. The 46th US Rock Mechanics/Geomechanics Symposium, Chicago, 24-27 June 2012, ARMA 12-291.

[16]   Aybar, U., Eshkalak, M.O., Sepehrnoori, K. and Patzek, T.W. (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.
http://dx.doi.org/10.1016/j.jngse.2014.09.030

[17]   Klinkenberg, L.J. (1941) The Permeability of Porous Media To Liquids And Gases. API, Washington DC.

[18]   Eshkalak, M.O., Mohaghegh, S.D. and Esmaili, S. (2014) Geomechanical Properties of Unconventional Shale Reservoirs. Journal of Petroleum Engineering, 2014, Article ID: 961641.
http://dx.doi.org/10.1155/2014/961641

[19]   Aybar, U., Yu, W., Eshkalak, M., Sepehrnoori, K. and Patzek, T.W. (2015) Evaluation of Production Losses from Unconventional Shale Reservoirs. Journal of Natural Gas Science and Engineering, 23, 509-516.
http://dx.doi.org/10.1016/j.jngse.2015.02.030

 
 
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