Assisted History Matching (AHM) is a systematic procedure of modifying parameters of a reservoir model to reproduce its dynamic response. Unlike traditional history matching (HM), where non-systematic manual adjustments on few engineering parameters are made on a single model to match the production data, AHM is part of an integrated study where engineering and geological consistent modifications are made to a reservoir model with the aid of efficient optimization techniques allowing the incorporation of multiple data types, such as production and 4D seismic, while also providing a vehicle for uncertainty assessment.
During the last decade, Shell has developed a number of methodologies to computer-automate the process of updating the large-scale reservoir parameters. These methodologies have been standardized and replicated in multiple fields and include assisted parameter estimation, which uses MCMC sampling techniques with experimental design-based proxies, and model maturation, which uses (adjoint) gradient-based updates to identify and correct (major) omissions (under-modeling) in the static and dynamic model. In this presentation, these methodologies will be presented and the results of their application in some field examples will be demonstrated.