Alaskan exploration and development activity continues to perk up.
ARCO Alaska Inc. last week disclosed two oil discoveries on the North Slope west of giant Kuparuk River oil field. It plans further drilling in the area in an effort to prove more reserves to justify installation of another central processing unit on the North Slope.
In Alaska's Cook Inlet, Unocal Corp. outlined a program for further development of reserves in the Granite Point oil field area.
Earlier this year, ARCO drilled a major discovery off the North Slope, the 3,400 b/d 1 Kuvlum (OGJ, Oct. 19, p. 40), and two significant oil strikes were announced by ARCO (OGJ, Nov. 4, 1991, p. 39) and Anchorage independent Stewart Petroleum Co. in the Cook Inlet area (OGJ, Aug. 3, p. 33).
ARCO STRIKES
ARCO drilled the two discovery wells on the western Colville High about 10 miles of Kuparuk River field during this winter's drilling season.
ARCO 1 Fiord flowed 1,065 b/d of 32 gravity oil with 500:1 GOR through a 24/64 in. choke with 600 psi wellhead pressure from one zone. A second interval, after hydraulic fracturing, flowed an average 180 b/d of 26 gravity oil through an 18/64 in. choke with 50 psi wellhead pressure.
ARCO's 1 Kalubik also found two zones. The first flowed at an average 1,200 b/d of 26 gravity oil with 450:1 GOR through a 1/2 in. choke with 380 psi wellhead pressure. A second interval, after hydraulic frac, flowed an average 410 b/d of 21 gravity oil with 250 GOR through a 12/64 in. choke with wellhead pressure of 315 psi.
No pay depths were disclosed. ARCO drilled 1 Fiord, in 2-12n-5e, to 10,250 ft measured depth, 9,973 ft true vertical depth. It drilled 1 Kalubik to 8,273 ft as a straight hole.
ARCO's partner in the two wells is Union Texas Petroleum Alaska.
DRILLING PLANS
ARCO plans to drill three more wildcats on the western Colville High during the 1993 winter drilling season, said James Davis, ARCO Alaska senior vice-president for exploration and land.
In an area 18-22 miles generally north-northeast of Nuiqsut, ARCO will drill 3 Kuukpik in 22-13n-6e, 5 Kuukpik in 20-13n-5e, and 1 Till in 3-12n-6e. The Fiord, Kalubik, and both Kuukpik wells are in the 90,000 acre Kuukpik exploratory unit in which Amerada Hess Corp. also holds an interest.
"We are looking for sufficient reserves to justify putting in a central processing facility west of Kuparuk," Davis said.
Amerada and Texaco Inc. drilled four oil discoveries on the Colville River Delta during the 1980s, all noncommercial at the time. All are within the boundaries of the Kuukpik Unit, about 3-12 miles east of the Fiord and Kalubik wells.
Upon completion of the 1993 drilling program in on the Kuukpik Unit, ARCO will hold about 65,500 net acres and Union Texas and Amerada each about 12,000 net acres in the unit.
LEASE SALE RESULTS
ARCO said results of the recent Kuparuk uplands state lease Sale 75 are important to continuing exploration of the Colville High area.
ARCO dominated the sale as apparent high bidder on 42 tracts covering more than 95,000 acres. It accounted for almost $8 million of the sale's apparent high bid total of $9.75 million. The company apparently acquired the sale's top per acre bid tract, a 1,920 acre lease on the Colville Delta.
Union Texas was apparent high bidder on two tracts covering about 3,100 acres and will acquire about a 15% interest in 17 tracts covering 34,000 acres on which ARCO was apparent higher bidder. Union Texas offered the sale's top apparent high bid, about $860,000 for a 2,459 acre parcel just east of the Colville Delta.
Sale 75, held Dec. 8 in Anchorage, garnered 81 bids for 55 tracts.
COOK INLET PLANS
Unocal plans to resume development drilling from the Granite Point platform in Cook Inlet, based on success of four wells drilled under a first phase, after completing a facilities upgrade.
The program entails using extended reach drilling to boost productivity of Granite Point's main producing zone, Oligocene middle Kenai (Tyonek). Unocal also plans more wells to tap Oligocene Hemlock pay discovered earlier this year.
As part of the initial phase, the first two extended reach Tyonek wells have been completed and are producing at rates four to five times greater than conventional Tyonek wells.
The second phase of Granite Point further development calls for drilling another 12 wells during 4 years. That's expected to add production of 7,000 b/d of oil and 4.9 MMcfd of gas.
Unocal has completed two Hemlock development wells, including the zone's discovery well drilled in March. In all, the four newly completed wells have jumped platform production to 5,200 b/d from 2,300 b/d.
Granite Point Hemlock discovery well 11-13RD flowed 1,440 b/d of oil and 1 MMcfd of gas through an I'/64 in. choke with flowing tubing pressure of 1,550 psi from perforations at 11,032377 ft. Total depth is 11,560 ft.
Prior to beginning the second phase, Unocal plans to add a gas compression unit to the platform. Once that project is complete, development drilling would resume in 1994.
Granite Point platform has been in operation since 1967, and the field has produced more than 115 million bbl of oil. Unocal, with a 25% interest, is operator of Granite Point platform, with the remaining 75% held by Mobil Exploration & Producing U.S. Inc.
Copyright 1992 Oil & Gas Journal. All Rights Reserved.