Abstract

Edsel field, discovered by Davis Oil Co. in November 1981, produces from a stratigraphic trap in the upper "B" sand member of the Permian Minnelusa Formation. The field is located in T54N-R68W, Crook Co., Wyoming, in the northeast part of the Powder River Basin. The field had an estimated 6.257 million barrels of original oil in place (OOIP) and is expected to yield 775,000 barrels of primary oil from approximately 380 productive acres. It is estimated that a polymer augmented waterflood will increase the ultimate recovery to 2.49 million barrels of oil or 40 percent of the OOIP. Eight wells produce from the main field pay, the upper "B" sand, and two wells produce from other zones within the Minnelusa. The upper "B" sand averages 21.5 feet of net pay, has an average porosity of 19.6 percent and an average water saturation of 47 percent. The upper and lower "B" sands form a complementary pair, filling the interval between the Opeche Shale and the "B" dolomite. Thick upper "B" sands are present above thin lower "B" sands, and conversely, the upper "B" sand pinches out over the top of thick lower "B" sands. Recognizing the significance of the complementary relationship of the upper and lower "B" sands allows for exploration for certain traps in the Minnelusa which may not be found using conventional methods.