BC’s Beaver River field flows gas from shales

Oct. 27, 2008
The life of Northeast British Columbia’s Beaver River field may be extended if initial flows from shale and siltstone formations prove out in the Liard basin field.

The life of Northeast British Columbia’s Beaver River field may be extended if initial flows from shale and siltstone formations prove out in the Liard basin field.

Two Canadian independent operators reported an initial flow of 10 MMcfd of sweet, dry gas at 3,000 psi wellhead pressure on a 3-day test at the field’s A-5 well.

The gas flow came from a brittle layer, rich in dolomite, at the top of a thick sequence of organic rich shale after a series of minifracs and high-pressure acid stimulations. The goal of the exercise was to identify prospective intervals for a future frac stimulation program.

Pending regulatory approval, the well will go on production by the end of October, said Questerre Energy Corp. and Transeuro Energy Corp.

Questerre Energy said, “While too early to evaluate the full contribution from the Liard shales, these initial results are well above our expectations. With over 30 sq miles of prospective acreage, existing infrastructure and takeaway capacity, this remains an exciting opportunity.”

Questerre, which operates the field, said the high flowing pressure associated with this well will likely reduce production from the lower pressure A-2 and A-7 wells, limiting overall production gains.

Transeuro said it expects the gas rate to decline initially and is confident it will stabilize at commercial levels.

Beaver River field, 150 km northwest of Fort Nelson, BC, is near the provincial border with Yukon and 100 km east of the Horn River basin, which has an emerging gas play in the Devonian Muskwa and Evie shale.

A-5 is the third well to be put on production from the shale-siltstone intervals at Beaver River field, said Transeuro. The intervals are collectively more than 2,000 m thick and for classification purposes have been separated into three major intervals.

The intervals are the Mississippian Mattson shale at 1,200-2,100 m, producing in the A-7 well; the Devonian Besa River shale at 2,000-3,000 m, producing in the A-2 well; and the Devonian Golata and Muskwa shales at 3,000-4,000 m. The Muskwa is not yet tested at Beaver River.

Transeuro said, “The appraisal strategy for the shale is to target the more brittle rock intervals that have higher carbonate and silica content and are therefore expected to respond favorably to stimulation. The brittle rocks contain free gas and may serve as a pathway for the shale gas to enter the well. The long-term production test is intended to establish how much gas can be recovered from the surrounding shale through the stimulated layer.”