|
Oooguruk participating areas changes OK’d
Caelus Energy Alaska applies for, receives, expansions at three Oooguruk PAs — Nuiqsut, Kuparuk, Torok — contraction at Torok PA Kristen Nelson Petroleum News
Caelus Energy Alaska has received approval from the Alaska Division of Oil and Gas for expansions at three participating areas in the Oooguruk unit along with a contraction at one of the three.
Participating areas are the portions of units from which production is occurring; the unit is not being expanded.
The division said in July 11 approvals that the Oooguruk unit encompasses some 53,344 acres within 25 state leases.
The Oooguruk Nuiqsut participating area contains 16,987 acres and will be expanded with an additional 1,600 acres for a total of almost 18,600 acres. The Oooguruk Kuparuk PA comprises some 5,160 acres within the unit and the expansion will add some 600 acres adjacent to the northeast boundary of the existing PA, for a total of 5,760 acres. The Oooguruk Torok PA is being expanded and contracted, the division said, with some acreage removed from the southern end of the PA and a small acreage added to the northern end of the PA. The division did not summarize the acreage for the Torok PA, but a table shows 120 acres added and 1,000 acres contracted. The Torok PA was originally 1,720 acres; 1,320 acres were added in a 2013 PA expansion, for a total of 3,040 acres; with the expansion and contraction that would appear to result in an acreage total of 2,160 for Torok, the smallest of the Oooguruk PAs.
The Oooguruk unit was formed in 2003 with Pioneer Natural Resources Alaska Inc. as the operator; Caelus succeeded Pioneer as operator in 2014.
Oooguruk Nuiqsut PA The Oooguruk Nuiqsut PA expansion approval is the third expansion for that PA, following expansion approvals in 2013 and 2014. The division said the third expansion encompasses portions of nine state oil and gas leases within the unit. Caelus is the Oooguruk operator and holds a 70 percent working interest; the remaining 30 percent is held by Eni Petroleum US LLC.
The division said the proposed third expansion of the Oooguruk Nuiqsut PA “is based upon drilling results that have demonstrated the presence of productive Nuiqsut Reservoir sands to the north, northwest, and southwest beyond the original ONPA boundary,” noting that Caelus has optimized its well designs and drilling trajectories to extend its drill reach from the offshore drill site island beyond the original Nuiqsut PA boundary into the requested expansion area.
“The development wells drilled into the expansion area have demonstrated the capability of producing or contributing to the production of hydrocarbons in paying quantities from the Nuiqsut reservoir.”
Exploration began in the Colville Delta area in 1970 and between 1970 and 1998 15 exploration wells were drilled in the area. “Some wells tested oil bearing sands in the Nuiqsut intervals, but at that time, the companies concluded that development was uneconomical,” the division said.
Pioneer Natural Resources drilled three exploration wells in the winter of 2003: Ivik 1, Oooguruk 1 and Natchiq 1. The division said Pioneer fracture-stimulated and tested the Ivik 1, which produced at an initial rate of 1,300 barrels of oil per day, with production from the Nuiqsut sandstone averaging 964 bpd during a four-day test. Oil samples from the Ivik 1 and Oooguruk 1 wells tested 19-24 degree API gravity oil from Nuiqsut, heavier than the 39 degree API gravity oil from the Alpine field and closer in oil gravity to the Kuparuk River field. The division said Nuiqsut oil also contains 2-4 percent wax by weight.
Pioneer drilled and completed one horizontal production well in the Oooguruk Nuiqsut reservoir in 2008 and initiated production from that well within the Oooguruk Nuiqsut PA on Aug. 12, 2008. Pool rules for the Oooguruk Nuiqsut reservoir were approved by the Alaska Oil and Gas Conservation Commission in March 2008. Pioneer’s plans were to develop the Nuiqsut reservoir with 30 to 39 horizontal wells, evenly split between producers and injectors. Water alternating gas injection for the Oooguruk Nuiqsut oil pool was approved by the commission in 2010.
Twenty-eight wells have been drilled in the Oooguruk Nuiqsut PA, 17 production and 11 injection wells, and the Nuiqsut reservoir has produced 23.3 million barrels, with December 2017 production at 11,500 bpd from 13 producing wells.
Oooguruk Kuparuk The application to expand the Oooguruk Kuparuk PA adds 600 acres to the northeastern edge of the PA. Formation of the Oooguruk Kuparuk PA was approved in 2009, retroactive to June 2008 when regular production began from the PA.
Cumulative production from the Oooguruk Kuparuk PA through 2017 is some 8.7 million barrels of oil, with an expected ultimate recovery of 10.4 million barrels, the division said. Original oil in place in the expansion area is estimated at some 6.6 million barrels of oil, with expected ultimate recovery from the expansion area, assuming no additional development beyond production from the ODSN-29 well, at 600,000 barrels of oil.
There are six Kuparuk wells in the current PA, four of which are active - two producers and two injectors.
Drilling into the expansion area began in 2011, and while wellbores encountered some 16 feet of Kuparuk C sandstone, there was no sustained production, despite well work from 2012 thru 2013.
A rig workover at the existing ODSN-29 well in September 2017 isolated the Nuiqsut interval and completed, perforated and tested the approximately 37-foot thick Kuparuk interval in the well, which since October has consistently produced some 1,500 bpd from the Kuparuk interval. The Nuiqsut interval, producing some 450 bpd, has been temporarily shut in during testing of the Kuparuk interval. The division said the long-term plan is to either get AOGCC approval to commingle production from the two intervals or to alternate production between the two.
Oooguruk Torok Several of the exploration wells drilled in the Colville River delta between 1965 and the early 2000s encountered the Torok formation at true vertical depths of 4,000 to 6,000 feet while drilling to deeper targets such as the Kuparuk and Sadlerochit.
A Nuiqsut development well, ODSN-45, was plugged back and sidetracked in 2010 due to operational difficulties and recompleted as a horizontal producer in the Torok formation, with sustain oil production beginning in March 2010 and averaging 530 bpd over the following year. Oooguruk Torok oil pool rules were approved by AOGCC in May 2011, with approval of the formation of the Oooguruk Torok PA approved by the division in June 2011. The PA was expanded by the division in March 2013.
The ODST-47 producer was not capable of contributing to production beyond some 716 barrels recovered from an initial flowback over five days in May 2013; the ODST-45A is currently the only producer online, with some 145 bpd with a 52 percent water cut.
As of June 31, 2017, the Torok PA had produced some 860,000 barrels of oil, primarily from two producers, with some 100,000 barrels from pre-production of an injection well.
Since the ODST-47 wellbore is not capable of producing in paying quantities, the area of the Torok PA encompassing that well will be contracted out of the PA. “The ODST-46i wellbore was drilled after the last OPTA revision, expanding the drainage area of the OTPA. Because of this, the PA is expanded to the northwest,” the division said.
| 