The State of Alaska has approved a 2,400-acre expansion of the Nuiqsut participating area at Pioneer Natural Resources Alaska’s North Slope Oooguruk field.
The expansion is projected to add 39 million barrels of recoverable crude oil to the original participating area estimate of 45-102 million barrels from primary production and secondary recovery with waterflood and water-alternating-gas mechanisms.
The approval came in a May 14 decision by the Alaska Department of Natural Resources’ Division of Oil and Gas.
The Nuiqsut participating area was approved in 2009 and Pioneer applied for the expansion in May 2012.
The division said confidential data submitted by Pioneer indicated the expansion area “is reasonably estimated to be capable of producing or contributing to production of hydrocarbons in paying quantities.”
To the northwestThe expansion area is to the northwest of the original PA.
The division said the expansion is based upon drilling results which demonstrated that there are productive Nuiqsut reservoir sands to the northwest beyond the original PA boundaries.
Pioneer has optimized its well designs and drilling trajectories to extend the drilling reach from its offshore drill site into the expansion area and has submitted data demonstrating that wells drilled into the expansion area are capable of producing or contributing to production in paying quantities, the division said.
When the Nuiqsut PA was approved in 2009 (effective June 1, 2008) the division said the depositional model for the Nuiqsut sands “suggested that reservoir quality would deteriorate to the northwest but the drilling results confirm that excellent reservoir quality Nuiqsut sand is present.”
Another factor in establishing the original PA boundary was “the practical extended drilling distances” possible from the offshore drilling site, but modifications Pioneer has made in its drilling design allowed significant increases in drilling distances, the division said.
Pioneer has drilled 17 Oooguruk Nuiqsut PA wells to date and is currently drilling two wells in the proposed expansion area, the division said.
Production from the PA is some 4,670 barrels per day.
Oooguruk Nuiqsut PA oil ranges from 19-24 degrees API gravity, heavier than the 39 degree API gravity oil produced at Alpine and nearer in oil gravity to oil from the Kuparuk River field, the division said. Nuiqsut oil also contains 2-4 percent wax by weight.
Nuiqsut majority of productionAs of the end of March Oooguruk field production totaled 12.8 million barrels. The majority of Oooguruk production comes from the Nuiqsut PA; the field also produces from the Kuparuk and Torok PAs.
Pioneer operates Oooguruk on behalf of itself and Eni Petroleum.
Production began from the Nuiqsut pool at Oooguruk, followed by the Kuparuk pool and the most recently Torok pool.
The division said 15 exploration wells were drilled in the Colville Delta-Oooguruk area between 1970 and 1998.
“A number of the wells tested oil bearing sands in the Nuiqsut intervals, but at that time, the companies concluded that development was uneconomical,” the division said.
Pioneer began drilling in the area in 2003, with three exploration wells — Ivik 1, Oooguruk 1 and Natchiq 1. Pioneer fracture stimulated and tested the Ivik well, with initial production at 1,300 barrels per day; a four-day test of the Nuiqsut sandstone averaged 964 bpd.
The division said it approved the plan of development for the Oooguruk unit in May 2012, effective June 11, 2012, through June 10, 2013. During the sixth plan period Pioneer drilled three horizontal Nuiqsut PA wells, one of which was drilled into the proposed expansion area. Pioneer’s seventh plan of development, pending division approval, proposes four wells into the expansion area, two of which are being drilled. Those are production wells. The division said Pioneer also plans two injectors for the 2014 drilling season.