Geologically Consistent Seismic History Matching Workflow for Ekofisk Chalk Reservoir
E. Tolstukhin, L.Y. Hu and H.H. Sudan
Event name: ECMOR XIV - 14th European Conference on the Mathematics of Oil Recovery
Session: History Matching I
Publication date: 08 September 2014
Info: Extended abstract, PDF ( 5.02Mb )
Price: € 20
Reservoir surveillance using 4D seismic has become a valuable resource for managing decisions under uncertainty. This paper highlights an integrated workflow that preserves geological consistency while calibrating a reservoir model using 4D seismic and production data. We demonstrate a successful application of this integrated approach on the Ekofisk chalk reservoir in the North Sea. Geological and seismic consistency is preserved by using reservoir model perturbation techniques based on Multi-Point Statistics (MPS) Morphing concept, incorporation of 4D seismic data, rock physics forward modeling, and simulation model update using a computer assisted history matching procedure. Uncertain geological parameters were updated in a loop using a proxy-based optimization algorithm through minimization of an objective function that contained both production and 4D seismic misfits. The presented approach dynamically coupled all elements of seismic to simulation workflow. The interpretation of 4D seismic attributes from consequent time-lapse surveys assisted in tracking injection water front advancement in the reservoir. This information was incorporated in the history matching process that resulted in calibrated models with updated fracture network distributions. These multiple calibrated models will provide valuable insights for future well planning in the region and provide options to optimize future well targets under uncertainty. The integrated workflow provided a quantitative mechanism to improve the predictability of the flow model. The approach yields improved reservoir management by encouraging multi-disciplinary collaboration between geological, geomechanical, geophysical and reservoir engineering disciplines.