Use of Parameter Gradients for Reservoir History Matching

Abstract

Use of Parameter Gradients for Reservoir History Matching F. Anterion; F. Anterion Elf Aquitaine Search for other works by this author on: This Site Google Scholar R. Eymard; R. Eymard Laboratoire Central des Ponts et Chaussees-Paris Search for other works by this author on: This Site Google Scholar B. Karcher B. Karcher Elf Aquitaine Search for other works by this author on: This Site Google Scholar Paper presented at the SPE Symposium on Reservoir Simulation, Houston, Texas, February 1989. Paper Number: SPE-18433-MS https://doi.org/10.2118/18433-MS Published: February 06 1989 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Anterion, F., Eymard, R., and B. Karcher. "Use of Parameter Gradients for Reservoir History Matching." Paper presented at the SPE Symposium on Reservoir Simulation, Houston, Texas, February 1989. doi: https://doi.org/10.2118/18433-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE Reservoir Simulation Conference Search Advanced Search AbstractIn reservoir simulation, history matching has long been performed in an empirical way. Applying inverse problem methods to reservoir simulation requires the calculation of gradients of observations at producing wells with respect to reservoir producing wells with respect to reservoir characteristics, which leads to a local linearisation of the full non linear reservoir simulation problem.This paper describes a rigorous analytical method for the computation of gradients. The gradient calculation has been implemented in the fully implicit, 3-phase, 3-dimensional reservoir simulator, SCORE, in a way which leads to significantly reduced computation time compared to other methods.The second part of the paper reports on a preliminary attempt at computer aided preliminary attempt at computer aided history matching, based upon a meta simulator which uses the calculated values of the gradients and a minimisation procedure together with several procedure together with several extrapolation laws. Two applications of the method are presented. They serve to demonstrate that the experience of the reservoir engineer cannot be replaced by such a method, used in an automatic way, because the system cannot decide which parameters should be changed. However, once an appropriate choice had been made, the meta-simulator provided an accurate estimate of the modified parameters which had to be used in order to simulate precisely the observed results.Application of this method increased the accuracy of the history match whilst significantly reducing both the number of computer runs and the total processing time required compared to other methods.IntroductionThe power of numerical reservoir simulation lies not only in the integration of reservoir data to give a forecast of future production but also in the ability to production but also in the ability to investigate the sensitivity of the forecast to different production schemes or to reservoir data which, at the time of simulation, may be poorly defined. Such poorly defined data may be considered to poorly defined data may be considered to form a set of parameters and a sensitivity study would consist of observing the change in results due to a change in one of the parameters. The same information is parameters. The same information is contained (to first order) in an evaluation of the gradient (derivative) of the results with respect to the parameter.To our knowledge, two different methods to evaluate the gradients have been published. The first, presented by Yang et al. is based on a solution of the adjoint equations and the second, due to See et al., uses a simple numerical difference of results obtained for different data. This latter method requires as many simulations as there are parameters to match.An automatic method which does not use gradients has been reported by Jennings et al., but this method is restricted to a small specialised simulator which is included explicitly within the minimisation procedure. procedure. P. 339 Keywords: spe 18433, gradient, extrapolation law, vertical transmissibility, flow in porous media, reservoir history, history, parameter gradient, pressure drop, transmissibility Subjects: Reservoir Fluid Dynamics, Reservoir Simulation, Flow in porous media This content is only available via PDF. 1989. Society of Petroleum Engineers You can access this article if you purchase or spend a download.