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Expanding Nikaitchuq As it completes initial developments, Eni is seeking new horizons at the field Eric Lidji For Petroleum News
Eni Petroleum is expanding its operations at its Nikaitchuq unit.
The Italian major is evaluating a previously undeveloped oil-bearing interval at the North Slope field in the waters of Harrison Bay, as well as multilateral completion techniques.
When Eni sanctioned Nikaitchuq in early 2008, the company based its development entirely on the oil contained in the OA sands of the Schrader Bluff formation. But Eni suggested it might someday pursue the shallower N sands of the same formation, or a minor oil accumulation encountered in the deeper Sag River formation. Now, as Eni nears the end of its initial slate of OA development wells, it is testing the N sands.
Sometime in the latter half of the year, Eni intends to drill three development wells at Nikaitchuq, one of which will primarily test oil production from the N sands reservoir.
It would be the first well Eni has drilled exclusively to evaluate the N sands.
The goal is to use the results of the test well and an ongoing reservoir modeling study “to plan a pilot well of this reservoir” in 2015. If the pilot proves the N sands to be economic, Eni envisions an “initial development phase” with four to nine “pre-development” wells.
Because the N sands are shallower than the OA sands, all previous drilling at Nikaitchuq has penetrated the interval, but Eni has also been testing the extent of the N sands by extending four existing horizontal OA sands wells into the northwest corner of the unit.
Additionally, Eni said it considering a second offshore drilling island at the unit, which would allow it to better target potential resources in the farther northwestern reaches.
Testing multilaterals In February, Eni tested an “alternative completion methodology” at Nikaitchuq by drilling a multilateral well from its offshore island, its first such well in Alaska.
Eni drilled the SP22-FN1 directional well to 22,923 feet measured depth and 3,408 feet vertical depth with four laterals ranging from 1,600 to 2,000 feet each. The results of the first well prompted the company to later drill OP08-OL41, a second multilateral well from its onshore pad. Unlike the first multilateral, Eni drilled the laterals of this second well after casing and cementing the main wellbore to improve the integrity of the well.
Should Eni ultimately sanction an N sand development, these multilaterals could allow it to develop both intervals simultaneously, or at least reduce its overall drilling footprint.
For now, though, Eni clearly sees multilaterals as an important next step for the field.
Eni plans to cold stack Nabors Rig 245 between November and March, when it would launch a workover campaign to convert eight existing Oliktok Point wells to multilaterals by drilling sidetracks between 6,000 and 10,000 feet in length. Eni is also considering a plan to drill all future Spy Island Drillsite wells as multilaterals starting in January 2014.
For its 2015 program, Eni is considering a workover campaign to convert eight existing Spy Island Drillsite wells to multilaterals with specifications similar to those envisioned for the Oliktok Point pad. This would come on top of the proposed N sands development.
Both campaigns are contingent on corporate approval, the company said.
Production up, “uncertain” Eni is developing Nikaitchuq through a combination of onshore wells from a pad at Oliktok Point and offshore wells from an artificial drilling site near Spy Island.
Eni released one rig from its program in October 2012 after completing its initial slate of OA sands wells planned for the Oliktok Point pad, but with the three-well program planned for this summer — which includes the N sands test well — the company now plans to conduct “intermittent” drilling from the onshore pad using Nabors Rig 245.
Since last November, Eni has been conducting “continuous” drilling from the Spy Island Drillsite using Doyon Rig 15. The program includes four production and five injection wells, which include the N sands extensions, and is scheduled to run through November.
Eni expects to complete its initial slate of offshore wells in November 2014.
In addition to its development drilling, Eni has also been conducting or plans to soon conduct workovers from both drilling pads this year — three rigless and four rigged.
While Eni expects this activity to increase production this year to as much as 14,000 barrels per day up from 10,000 bpd, the company expressed “significant uncertainty concerning the production potential from the wells to be drilling in the coming year.”
Sag River development? In addition to its N sands appraisals planned for the coming year, Eni is also in the early stages of evaluating a potential development of the Sag River formation at Nikaitchuq.
The program would require Eni to build a second artificial island to better reach prospects in the northwest corner of the unit. Eni said it intends to submit a proposal for such a development to its “upper management” within the next 12 to 18 months. The proposal or something similar could be necessary for Eni to keep all its acreage at the Nikaitchuq.
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