Application of Empirical Data in Forecasting Water Flood Behavior Available to Purchase

The use of empirical data to validate injection predictions and to prepare oil production forecasts is described. Histories of typical inputs show that reasonably reliable injection predictions can be made from equations based on Darcy's Law. The production performance of five Illinois floods is presented in a graph of accumulated increased recovery versus accumulated water injection per acre-ft, thereby permitting comparisons and forecast independently of time and input rate. The various steps used to apply this empirical data to a forecast are described, beginning with the method of estimating the accumulated injection necessary to achieve first production increase. Flood performance indicates this to be a function of permeability heterogeneity. The forecast of subsequent behavior is shown to consist of selecting the most appropriate empirical curve to use as a guide, with its selection based on relative reserves and degree of confinement. The introduction of time and rate is described as a stepwise integration of the accumulated production versus injection curve at the forecast injection rate.