A peripheral waterflood monitoring method of subdividing the Hemlock Reservoir into areal groups has aided in development decisions for the McArthur River Field, Cook Inlet, Alaska. This analysis technique improved assessment of remaining development potential by separating the reservoir into more manageable areas. By respecting the inaccuracies associated with production data, the analysis method simplified reservoir management and improved performance predictions.
Seven "performance areas" were established to monitor waterflood performance and identify areas of remaining recovery potential. Each performance area represents an accounting block in which recovery and performance prediction methods were applied to monitor waterflood progress. Prediction methods for the undersaturated reservoir included water-oil ratio trending, material balance and decline analysis. Comparison of each area's performance with others and with analytical performance predictions easily identified local areas of unrealized potential. This method of waterflood management aided in assembling management strategies and promptly examining those strategies as conditions changed.