HR: 08:40h
AN: H21K-03 INVITED    [Abstracts]
TI: Application of Model Based Uncertainty Analysis to Hydrocarbon Reservoirs
AU: * Lyons, S L
EM: steve.lyons@exxonmobil.com
AF: ExxonMobil Upstream Research Company, P.O. Box 2189, Houston, TX 77252-2189, United States
AU: Lee, L W
EM: libong.w.lee@exxonmobil.com
AF: ExxonMobil Upstream Research Company, P.O. Box 2189, Houston, TX 77252-2189, United States
AB: Model-Based Uncertainty Analysis (MBUA) is a method to evaluate reservoir performance uncertainty using multiple 3D models. Experimental Design techniques are used to determine what 3D models are built (unique geologic models which are then simulated) based on the number of identified uncertain factors. This method captures main effects and factor interactions and results in a multivariable response surface for each desired outcome (e.g. expected ultimate recovery, original hydrocarbon in place) which can be used for Monte Carlo simulations. The entire MBUA process results in tornado plots, exceedence curves, and a method to build representative models. A key strength of the MBUA process is the ability to capture dynamic responses such as water rate, production at early times, and plateau length. These responses provide project teams a greater understanding of how their subsurface uncertainties impact field performance and can help guide additional technical work, development planning decisions and representative model building. We have applied either a full or partial MBUA process to several fields for the purposes of identifying key technical uncertainties and improving the development plan across likely outcomes. Once an initial base case model has been built, subsequent models (totaling 16-54 models) can be rapidly built and simulated using normal geologic and flow simulation model workflows. While the analysis is quick, all model results are required to complete the analysis, thus simulation time is the biggest bottleneck in the process. Production data have been incorporated through either history-matching the initial base case or examining Monte Carlo simulation results for potential trends. The uncertainty analysis provides a streamlined process to examine potential uncertainty factors and allows a project to make informed decisions regarding future technical work or potential mitigation plans. A process overview will be presented along with sample results and lessons from completing the full MBUA.
DE: 1873 Uncertainty assessment (3275)
SC: Hydrology [H]
MN: 2007 Fall Meeting