Risk Assessment and Simulation of Injectivity Decline Under Uncertainty
- Maria-Magdalena Chiotoroiu (OMV E&P) | Torsten Clemens (OMV E&P) | Markus Zechner (OMV E&P/Stanford University) | Jongsoo Hwang (University of Texas) | Mukul M. Sharma (University of Texas) | Marco Thiele (Streamsim/Stanford University)
- Document ID
- Society of Petroleum Engineers
- SPE Europec featured at 81st EAGE Conference and Exhibition, 3-6 June, London, England, UK
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Petroleum Engineers
- 1.8 Formation Damage, 5.5 Reservoir Simulation, 7.2.3 Decision-making Processes, 0.2.2 Geomechanics, 5.4.1 Waterflooding, 3 Production and Well Operations, 6.3 Safety, 0.2 Wellbore Design, 5 Reservoir Desciption & Dynamics, 7.2 Risk Management and Decision-Making, 7.2.1 Risk, Uncertainty and Risk Assessment, 7 Management and Information, 5.4 Improved and Enhanced Recovery, 3 Production and Well Operations
- uncertainty assessment, water injectivity, risk, development options, Value of Information
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- 102 since 2007
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Waterflooding can lead to substantial incremental oil production. Implementation of water injection projects requires the project to fit into the risk (defined here as negative outcomes relative to defined project objectives) and uncertainty (defined here as inability to estimate a value precisely) a company is willing to take.
One of the key risks for water injection into a shallow reservoir is injection induced fractures extending into the caprock. If this risk is seen as "Intolerable" in an As Low As Reasonable Practicable (ALARP) analysis a decision may be made to not proceed with the project., In this study we evaluated caprock integrity by conducting simulations of long-term water injection that include the effects of formation damage caused by internal/external plugging, geomechanical stress changes and fracture propagation in the sand and bounding shale.
The risk of fracture growth into the caprock was assessed by conducting Monte-Carlo simulations considering a set of modelling parameters each associated with an uncertainty range. This allowed us to identify the range of operating parameters where the risk of fracture height growth was acceptable. Our simulations also allowed us to identify important factors that impact caprock integrity. To cover the uncertainty in geomechanical reservoir evaluation, the operating envelope is identified such that the risk of the caprock integrity is reduced. This requires introducing a limit for the Bottom Hole Pressure (BHP) including a safety margin.
The limit of the BHP is then used as a constraint in the uncertainty analysis of water injectivity. The uncertainty analysis should cover the various development options, the parametrisation of the model, sampling from the distribution of parameters and distance-based Generalized Sensitivity Analysis (dGSA) as well as probabilistic representation of the results.
The dGSA can be used to determine which parameter has a strong impact on the BHP and hence the project and should be measured if warranted by a Value of Information analysis.
The final development option to be chosen depends on a traditional NPV analysis.
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Simpson, G.S.; Lamb, F.E.; Finch, J.H. and N.C. Dinnie. 2000. The Application of Probabilistic and Qualitative Methods to Asset Management Decision Making. Paper SPE 59455 presented at the 2000 SPE Asia Pacific Conference on Integrated Modelling for Asset Management. Yokohama. Japan. 25-26 April 2000.
Tilkie, P.G.; Banerjee, R.; Halabe, V.B.; Balci, B.; Thambynayagam, M. and J. Spath. 2010. Automated Field Development Planning in the Presence of Subsurface Uncertainty and Operational Risk Tolerance. Paper SPE 135168 presented at the SPE Annual Technical Conference and Exhibition Florence. Italy. 19-22 September 2010.
Al-Lawati, M.H.A. ; Kindi, F. ; Busaidi, S.; Schoofs, S.; Ita, J.J. and F. Van Der Heyden. 2012. Integrated Surveillance and Modelling to Monitor Risk of Fault Re-activation During Steam Injection. Paper SPE 155600 presented at the SPE EOR Conference at Oil and Gas West Asia. Muscat. Oman. 16-18 April 2012.
Durucan, S.; Shi, J.Q.; La Torre Guzman and A. Korre. 2016. Reservoir geomechanics helps improve CO2 storage performance and risk assessment. Paper ISRM-EUROC-2016-005 presented at the Rock Mechanics and Rock Engineering: From the Past to the Future. Ulusay(Eds) Taylor&Francis Group. London. ISBN 978-1-138-03265-1.
Guo, Q, Geehan, T and Pincock, M. 2005. Managing Risks and Uncertainties in Drill Cuttings Re-Injection in Challenging Environments - Field Experience from Sakhalin Island. Paper SPE 93781 presented at the 2005 SPE/EPA/DOE Exploration and Production Environmental Conference. Galveston. USA. 7-9 March 2005.
Joranson, H.; Klein, H.H.Raaen, A.M. and M.B. Smith. 2007. Better Reservoir Management Through Improved Water-Injection Methods With Data Analysis and Detailed Fracture/Reservoir Modeling. Paper SPE 110329 presented at the 2007 SPE Annual Technical Conference and Exhibition. Anaheim. USA. 11-14 November 2007.