Reservoir management under geological uncertainty using fast model update

Statoil is implementing "Fast Model Update (FMU)," an integrated and automated workflow for reservoir modeling and characterization. FMU connects all steps and disciplines from seismic depth conversion to prediction and reservoir management taking into account relevant reservoir uncertainty. FMU delivers an ensemble of geologically-consistent and history-matched model realizations that together characterizes the reservoir uncertainty. FMU facilitates management of the reservoir (e.g. field development plan, well planning, and drainage strategies) in both early-phase as well as mature projects, properly taking geological uncertainty (including structure, facies, and rock/fluid properties) into account. The focus of the paper is to demonstrate how FMU is used in an algorithm for robust optimization of wells (e.g. well targets, infill wells, drilling priority, rate control). In the current paper we demonstrate some early results where the drilling sequence of wells is optimized under geological uncertainty, using an ensemble of models conditioned on all available data. The final product provides an optimized drilling schedule and drilling time. The paper includes examples from one synthetic and one real field application. Copyright © 2015, Society of Petroleum Engineers.

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