A joint venture led by Brooks Range Petroleum Corp. found oil at a North Slope exploration well this year, but won’t be able to fully test the well until next winter.
The companies spud the North Tarn No. 1 well on March 13 from an ice pad two miles west of the Kuparuk River unit and reached a measured depth of 6,223 feet by March 22, deep enough to test reservoir targets in the Brookian and the deeper Kuparuk sandstones.
The companies did not log the Kuparuk sandstones and could not estimate net pay, though, because of “well control challenges” including “strong mud gas shows with high oil-cut mud and gas flow to surface tanks.” Based on samples of sandstone cuttings and gas readings taken from the well, they estimate the Kuparuk to be about 20 to 25 feet thick at North Tarn No. 1, comparable to the Kuparuk C1 sandstone in two nearby wells.
On April 11, the companies drilled a “substitute well” using the existing surface hole. By April 14, the well reached a measured depth of 6,086 feet, to the base of the Kalubik Formation, just above the Kuparuk C sand, and the companies set intermediate casing.
BRPC is operating the well on behalf of its parent company, the Kansas-based Alaska Venture Capital Group LLC, as well as three joint venture companies: Brooks Range Development Corp., Ramshorn Investments Inc. and TG World Energy Inc.
North Tarn No. 1 was the only exploration well on the North Slope this winter.
See more in April 24 issue of Petroleum News, available online at 11 a.m., Friday, April 22 at www.PetroleumNews.com