There’s a new unconventional play in town, and it hails from the Uinta Basin. The Uteland Butte, the basal carbonate member of the Eocene Lower Green River formation, is gaining traction as an oil-prone resource play. Three veteran explorers are investigating the promising zone, and more results are expected imminently.

Houston-based Newfield Exploration unveiled the Uteland Butte play this summer. It reported that it had completed six horizontal Uteland Butte oil producers in a 10-square-mile area on the western flank of Monument Butte Field. The tests, in Duchesne and Uintah counties, Utah, were completed for 24-hour initial potential (IP) rates that averaged approximately 500 barrels of oil equivalent (Boe) per day, and were drilled and completed for less than $3 million apiece. Those rates are more than six times the typical IP of a traditional, vertical Green River well.

Newfield has said that the carbonate, which occurs at depths between 6,000 to 9,000 feet, is present across its Monument Butte holdings (where it is normally pressured) and to the north and northwest in the Central Basin area (where it is overpressured).

Based on an estimated inventory of at least 1,800 locations at assumed 160-acre spacing, and covering some 80% of its 250,000 net acres in the Uinta, Newfield has calculated the Uteland Butte’s net resource potential at nearly 300 million Boe. Individual wells are presumed to recover 300,000 Boe each.

The company planned to complete a total of 10 Uteland Butte horizontals by year-end 2011, and to drill more than 30 during 2012.

Newfield further affirmed its affinity for the play in early January, when it announced a new oil supply agreement in the Uinta Basin, its second such agreement in as many months. Between the two, Newfield has now secured some 40,000 barrels a day of refining capacity to accommodate its projected growth in oil production.

The main plays supporting this production ramp are the horizontal Uteland Butte and the vertical Wasatch. Newfield expects to run at least eight rigs in the basin this year, up from five in 2011.

Denver independent Bill Barrett Corp. is also active, and it is working in the overpressured portion of the play. The company galvanized the industry in August 2011 when it announced that its first horizontal Uteland Butte producer, drilled in Altamont Field in Duchesne County, flowed at an initial rate of 1,300 Boe per day. It averaged a stout 717 Boe per day during its first 30 days on line. The #13H-20-46 Lake Canyon-Tribal is producing from a 3,100-foot horizontal lateral in the Uteland Butte that was fracture-stimulated in 15 stages.

The company’s first four Uteland Butte horizontals have averaged peak 24-hour IP rates of more than 1,000 Boe. Specifically, Barrett’s third and fourth wells posted peak IP rates of 1,330 Boe and 863 Boe per day, respectively. Vertical depths to the formation were just shy of 6,000 feet, and laterals ranged from 3,200 to 3,400 feet on its third and fourth wells.

Certainly, results are strong, and interest is at a fever pitch. Barrett’s initial well costs are in the neighborhood of $5 million each, but the company noted it should be able to reduce those to around $4 million over time. Much more will be revealed in late January, including the results of three additional Uteland Butte completions, when Barrett hosts an investor day.

Berry Petroleum is a third Uinta producer looking hard at the Uteland Butte. The company notes that it has identified a zone on logs of existing wells across its acreage that is consistent with the Uteland Butte, and that scattered vertical wells completed in the zone have produced at rates of up to 80 barrels of oil per day.

Berry is a working interest partner in Bill Barrett’s first four announced Uteland Butte wells, and is also drilling its own wells. The explorer holds about 60,000 net acres with Uteland Butte potential. It estimates that it has 700 Uteland horizontal locations, and also a large number of vertical Wasatch locations, on its Utah properties. This is a play to watch for 2012!

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