Mathematical Geosciences

, Volume 48, Issue 4, pp 399–417 | Cite as

A Theoretical look at Ensemble-Based Optimization in Reservoir Management

  • Andreas S. Stordal
  • Slawomir P. Szklarz
  • Olwijn Leeuwenburgh
Article

Abstract

Ensemble-based optimization has recently received great attention as a potentially powerful technique for life-cycle production optimization, which is a crucial element of reservoir management. Recent publications have increased both the number of applications and the theoretical understanding of the algorithm. However, there is still ample room for further development since most of the theory is based on strong assumptions. Here, the mathematics (or statistics) of Ensemble Optimization is studied, and it is shown that the algorithm is a special case of an already well-defined natural evolution strategy known as Gaussian Mutation. A natural description of uncertainty in reservoir management arises from the use of an ensemble of history-matched geological realizations. A logical step is therefore to incorporate this uncertainty description in robust life-cycle production optimization through the expected objective function value. The expected value is approximated with the mean over all geological realizations. It is shown that the frequently advocated strategy of applying a different control sample to each reservoir realization delivers an unbiased estimate of the gradient of the expected objective function. However, this procedure is more variance prone than the deterministic strategy of applying the entire ensemble of perturbed control samples to each reservoir model realization. In order to reduce the variance of the gradient estimate, an importance sampling algorithm is proposed and tested on a toy problem with increasing dimensionality.

Keywords

Ensemble optimization Production optimization Robust optimization Natural evolution Gaussian mutation 

Notes

Acknowledgments

The first author acknowledges the Research Council of Norway and the industrial participants, ConocoPhillips Skandinavia AS, BP Norge AS, Det Norske Oljeselskap AS, Eni Norge AS, Maersk Oil Norway AS, DONG Energy AS, Denmark, Statoil Petroleum AS, GDF SUEZ E&P NORGE AS, Lundin Norway AS, Halliburton AS, Schlumberger Norge AS, Wintershall Norge AS, of The National IOR Centre of Norway for financial support.

References

  1. Akimoto Y, Nagata Y, Ono I, Kobayashi S (2010) Biderectional relation between CMS evolution strategies and natural evolution strategies. PPSN XI Part I LNCS 6238:154–163Google Scholar
  2. Amari SI (1998) Natural gradients works efficiently in learning. Neural Comput 10(2):333–339CrossRefGoogle Scholar
  3. Bouzarkouna Z, Ding D, Auger A (2011) Well placement optimization with the covariance matrix adaptation evolution strategy and meta-models. Comput Geosci:1–18Google Scholar
  4. Brouwer DR, Naevdal G, Jansen JD, Vefring EH, van Kruijsdijk CPJW (2004) Improved reservoir management through optimal control and continuous model updating. In: SPE Annual Technical Conference and Exhibition, Houston. Texas, pp 26–29 (SPE90149) Google Scholar
  5. Chen Y (2008) Efficient ensemble based reservoir management. Ph.d. thesis, University of OklahomaGoogle Scholar
  6. Chen Y, Oliver DS (2012) Localization of ensemble-based control-setting updates for production optimization. SPE J 17(1):122–136CrossRefGoogle Scholar
  7. Chen Y, Oliver DS, Zhang D (2009) Efficient ensemble-based closed-loop production optimization. SPE J 14(4):634–645CrossRefGoogle Scholar
  8. Ding YD (2008) Optimization of well placement using evolutionary algorithms. In: Europec/EAGE Conference and ExhibitionGoogle Scholar
  9. Do ST, Reynolds AC (2013) Theoretical connections between optimization algorithms based on an approximate gradient. Comput Geosci 17(6):959–973CrossRefGoogle Scholar
  10. Fonseca RM, Leeuwenburgh O, Hof PVD, Jansen JD (2013) Improving the ensemble optimization method through covariance matrix adaptation (cma-enopt). In: SPE Reservoir Simulation SymposiumGoogle Scholar
  11. Hansen N, Ostermeier A (1996) Adapting arbitrary normal mutation distributions in evolution strategies: The covariance matrix adaptation. In: 1996 IEEE International Conference on Evolutionary Computation. IEEE, pp 312–317Google Scholar
  12. Hansen N, Ostermeier A (2001) Completely derandomized self-adaptation in evolution strategies. Evol Comput 9(2):159–195CrossRefGoogle Scholar
  13. Hasan A, Foss B, Sagatun S (2013) Optimization of oil production under gas coning conditions. J Pet Sci Eng 105:26–33CrossRefGoogle Scholar
  14. Jansen J (2011) Adjoint-based optimization of multi-phase flow through porous media—a review. Comput Fluids 46:40–51CrossRefGoogle Scholar
  15. Jansen JD, Brouwer DR, Naevdal G, van Kruijsdijk CPJW (2004) Closed-loop reservoir management. In: EAGE 66th Conference & Exhibition. Paris, pp. 7–10 (Presented at Workshop “Uncertainties in production forecasts and history matching”) Google Scholar
  16. Leeuwenburgh O, Egberts PJ, Abbink OA (2010) Ensemble methods for reservoir life-cycle optimization and well placement. SPE/DGS Saudi Arabia Sect Tech Symp Exhib 4–7:2010Google Scholar
  17. Lorentzen RJ, Berg AM, Nævdal G, Vefring EH (2006) A new approach for dynamic optimization of water flooding problems. In: SPE Intelligent Energy Conference and Exhibition. Amsterdam, pp 11–13 (SPE99690) Google Scholar
  18. Lozano J, Larranaga P, Inza I, Bengoetxea E (2006) (eds) The CMA Evolution Strategy: a comparing review. Springer, pp 75–102Google Scholar
  19. Nwaozo J (2006) Dynamic optimization of a water flood reservoir. Ph.D. thesis, University of OklahomaGoogle Scholar
  20. Peters E et al (2011) Brugge paper SPE REEGoogle Scholar
  21. Pajonk O, Schulze-Riegert R, Krosche M, Hassan M, Nwakile MM (2011) Ensemble-based water flooding optimization applied to mature fields. SPE Middle East Oil Gas Show Conf 25–28:2011Google Scholar
  22. Raniolo S, Dovera L, Cominelli A, Callegaro C, Masserano F (2013) History match and polymer injection optimization in a mature field using the ensemble kalman filter. In: 17th European Symposium on Improved Oil Recovery, St. Petersburg, Russia. pp 16–18Google Scholar
  23. Rosenbrock H (1960) An automatic method for finding the greatest or least value of a function. Comput J 3(3):175–184CrossRefGoogle Scholar
  24. Sarma P, Durlofsky LJ, Aziz K, Chen WH (2006) Efficient real-time reservoir management using adjoint-based optimal control and model based updating. Comput Geosci 10:3–36CrossRefGoogle Scholar
  25. Schulze-Riegert R, Bagheri M, Krosche M, Kueck N, Ma D (2011) Multiple-objective optimization applied to well path design under geological uncertainty. SPE Reserv Simul Symp 21–23:2011Google Scholar
  26. Su H-J, Oliver DS (2010) Smart well production optimization using an ensemble-based method. SPE Reserv Eval Eng 13(6):884–892CrossRefGoogle Scholar
  27. Sun Y, Wierstra D, Schaul T, Schmidhuber J (2009) Efficient natural evolution strategies. In: Proceedings of GECCO. pp 539–545Google Scholar
  28. Tarantola A (2005) Inverse problem theory: methods for data fit-ting and model parameter estimationGoogle Scholar
  29. van Essen GM, Zandvliet MJ, van den Hof PMJ, Bosgra OH, Jansen JD (2006) Robust waterflooding optimization of multiple geological scenarios. In: SPE Annual Technical Conference and Exhibition, San Antonio. Society of Petroleum Engineers, Texas (SPE102913) Google Scholar

Copyright information

© International Association for Mathematical Geosciences 2015

Authors and Affiliations

  • Andreas S. Stordal
    • 1
  • Slawomir P. Szklarz
    • 2
  • Olwijn Leeuwenburgh
    • 3
  1. 1.International Research Institute of StavangerStavangerNorway
  2. 2.Institute of Applied MathematicsDelft University of TechnologyDelftThe Netherlands
  3. 3.TNOUtrechtThe Netherlands

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