Alberta Duvernay shale play awaits drilling
West-central Alberta is the site of a spirited land play for rights to liquids-rich potential in the Devonian Duvernay shale.
By OGJ editors
HOUSTON, Feb. 10 -- West-central Alberta is the site of a spirited land play for rights to liquids-rich potential in the Devonian Duvernay shale.
Industry’s first Duvernay horizontal well, operated by Celtic Exploration Ltd. last fall in the Kaybob area 150 miles northwest of Edmonton, flowed at a rate of 2.1 MMcfd of gas with 56° gravity condensate from a 1,787-m lateral at 3,300 m true vertical depth. Partner Yoho Resources Inc. said the well was expected to yield 75 bbl/MMcf of total liquids including the free condensate.
Mechanical problems prevented seven of the 13 planned frac stages at the well in 15-33-060-20w5. Yoho sees midcase well costs of $8-9 million excluding tie-in with ample room for improvement in cost per frac stage, initial potential, and ultimate recovery.
Celtic, Yoho, and Trilogy Energy Corp. spudded a second horizontal well, and Yoho plans to earn up to 20 more sections at Kaybob by drilling two vertical wells, boosting its stake to nearly 49 (17 net) sections. The wells spudded in December 2010 and January 2011.
Yoho sees 80-105 bcf/sq mile of gas in place in shale 130-180 ft thick with 7.1% average effective porosity and 1-4% total organic carbon.
Encana Corp. and Chevron Corp. both revealed large positions in the Duvernay play this week. Encana has 2011 plans to further evaluate the play, which it said has demonstrated “significant liquids potential.” Chevron said it accumulated 200,000 acres in play at a reasonable entry price.
Other independents that hold Duvernay acreage include Mooncor Oil & Gas Corp., Galleon Energy Inc., Orleans Energy Ltd., and Delphi Energy Corp., which has a large position in the Sturgeon Lake area. Another is Trilogy, a 2005 spinout from Paramount Resources Corp. Trilogy is developing the Montney and other tight sand formations at Kaybob.
Trilogy noted that the Duvernay formation is the basinal equivalent to the Lower Leduc reefs in central Alberta and is believed to be stratigraphically equivalent to the Muskwa shale that is being exploited in northeastern British Columbia. It said the Duvernay is considered to be the source rock for the Devonian oil and gas pools in central Alberta.
The Duvernay is among the shale formations targeted in an Alberta Energy Resources Conservation Board 2-year, $2 million resource assessment. The Alberta government has reduced royalty rates for shale gas wells.