The Effect of a Free Gas Saturation on the Sweep Efficiency of an Isolated Five Spot
I. D. R. NEILSON ; D. L. FLOCK
The objective of the research conducted and presented herein was to determine the effect of a pre-established free gas saturation on the sweep efficiency of an isolated inverted five-spot well pattern. The investigation concluded that the ultimate recovery of an isolated inverted five-spot may be slightly increased by establishing a free gas saturation prior to water flooding; however, of more significance is the extreme deviation of the pattern's performance after water breakthrough from that commonly obtained from developed well patterns. The rapid "water-out" characteristic common to both linear floods and floods conducted in developed well patterns was not evidenced in the isolated inverted five-spot. Instead, the wells continued to produce oil long after breakthrough until ultimate areal sweep efficiencies of four, five, and six hundred percent were obtained prior to the water-oil ratio becoming excessive. '!'he investigation further noted that these large areal sweep efficiencies could only be obtained if fill-up of the reservoir's initial gas saturation was obtained prior to breakthrough; otherwise, the rapid "water-out" characteristic common to linear floods and floods conducted in developed well patterns would prevail.
capillary pressure, inches of mercury, injection, saturation, University of Alberta, Efficiency, Flooding, Model, Models, Oil, Oils, Pressure, Water, Waters