| Description |
A 150 million barrel accumulation of heavy oil (14° API) underlies an 1120 acre Tom Brown, Inc. tract located six miles west of Vernal, Utah. A recently completed six-well corehole project provided the data to delineate this major accumulation. The following combination of geological and engineering factors make this an attractive target for thermal and/or chemical recovery:1) Concentration of reserves - approximately 150 million barrels of oil underlying an area of only 500 acres (300,000 B/ac). 2) Shallow depth - drilling depths range from 300' to 2000' with most reserves concentrated in the 500' to 1500' depth range. 3) Excellent reservoir rock quality - sandstones of the Mesaverde Formation, containing an estimated 126 million barrels of oil in place, exhibit good reservoir continuity and individual beds are as much as 70' thick. Further, a combination of high average porosity (31%) and high average oil saturation (69%) results in an average oil in place of 1660 B/ac ft for the Mesaverde sands. Tertiary age sandstones contain an additional 25 million barrels of oil in place. 4) Formation dip - all strata dip south-southwest into the Uinta Basin. Whereas the average dip of the Cretaceous Mesaverde Formation is 45°, the average dip of the unconformably overlying Tertiary strata is about 25°. These large dips enhance the potential for significant gravity drainage. 5) Sweet Crude - based on several published analyses, Asphalt Ridge crude is unusually low in sulphur, averaging only about 0.4% by weight. The prospect is further enhanced by good accessibility, moderate topographic relief (elevations range from 6000' to 6500') and proximity to a major oil field supply center, Vernal, Utah. The U. S. Bureau of Mines has recently announced plans for an experimental thermal recovery project on a ten-acre tract located one half mile east of the tract owned by Tom Brown, Inc. This U.S.B.M. field experiment is particularly relevant to our prospect because the reservoir-fluid con- ditions underlying the experimental tract are expected to be identical with those known to exist in the subsurface of the Tom Brown, Inc. tract. Because the experiment, which is in essence a pilot test, is being conducted by a Federal agency, the results will be made available to interested parties. |
