The Azeri-Chirag-Gunashli (ACG) oil field is located in the hydrodynamic environment of the South Caspian Basin (SCB). The presence of lateral pressure variations in such systems results in tilted hydrocarbon-water contacts. Besides the tilt, the eastern part of the field demonstrates unexpected fluid contacts observed from several appraisal and development wells. These unexpected contacts are not in accordance with tilts and cannot be explained by hydrodynamism only.
Proposed solution to explain contact anomalies in the eastern part of the structure is to analyze the effects of permeability barriers on fluid contacts in hydrodynamic environment. Analysis is done through mechanistic model simulations. It was determined that barriers influence the contacts in hydrodynamic aquifer environment and it is possible to explain aforementioned contact anomalies by plausible barrier arrangement.
Incorporation of study results into the Azeri full field model (FFM) resulted in better pressure and saturation match.