f Saturation Mapping from Combined 4D Seismic and Reservoir Simulation

4D seismic has the potential to monitor hydrocarbon movement in reservoirs during production, and could thereby supplement the predictions of the reservoir parameters offered by the reservoir simulator. However 4D seismic is often more bandlimited than the vertical resolution required in the reservoir model. As a consequence the seismic data holds a composite response from reservoir parameter changes during production so that the inversion becomes non-unique. A procedure that includes both the 4D seismic and reservoir simulations will be presented. The potential of such a procedure applied to a recent 4D survey over the Gullfaks field is demonstrated.