The Bakken formation is a continuous, unconventional-oil accumulation encompass­ing a large portion of the Williston Basin of Montana and North Dakota and extending into the southern portions of Canada’s Saskatchewan and Manitoba provinces. It is estimated to hold as much as 4.3 billion barrels of recoverable oil in the U.S. and 1 billion of recoverable reserves in Canada.

The Mississippian-age Bakken produces at depths as shallow as 2,000 feet in Canada and at depths of 11,000 feet in the U.S. It is composed of the organic-rich upper and lower shale members, which are source rocks for the basin, and the middle member, which is the primary producing reservoir. The middle member is up to 15 feet thick and litho­logically variable (dolomite/ sand/siltstone/shaley-lime/ shale), with porosity from 5% to 12% and low per­meability. Traps are primarily stratigraphic or in com­bination with structures. Oil quality is good, with gravity around 40 degrees API.

Production. The horizontal Bakken play currently being developed began in Montana’s Elm Coulee Field in 2001. Horizontal drilling and stimulation technology have been key to opening the play, but deposition variability is responsible for differing production profiles across the basin.

Basin operators have been drilling long laterals (about 10,000 feet), with 15 to 20-plus frac stages, at well costs between $5- and $6 million. Current U.S. Bakken production is 176,000 barrels of oil equivalent (BOE) per day (about 88% oil) from 1,700 active wells. Current Canadian Bakken pro­duction is about 110,000 BOE per day (about 90% oil) from approximately 1,400 active horizontal wells.

Development of the underlying Sanish and Three Forks formation could add significant reserves and production.

Major fields. The current U.S. play is concentrated in Elm Coulee Field, along and adjacent to the Nesson Anticline, and in Mountrail and Dunn counties, North Dakota. The Canadian play is concentrated in southern Saskatchewan, resulting from the interplay of a Middle Bakken calcareous sandstone/siltstone facies and proximity to structural features such as the Nesson Anticline and the Brockton-Fiord Lineament.

Competitor analysis. The Bakken is a well-established trend, yet it has seen recent expansions in activity and production through increased geological understanding and continued advance­ments in drilling, completion and stimulation. Well performance tends to be better within the core areas, but comparable results are now being achieved in many areas.

U.S. Bakken players

EOG Resources Inc., Houston, holds 500,000-plus net acres in the U.S. Williston Basin. Parshall Field, EOG’s core area, has posted recent IPs of 770 to 1,150 BOE per day with estimated ultimate recoveries (EURs) of 850,000 BOE. Noncore areas expect IP rates of 470 to 840 BOE per day with EURs of 300,000 barrels equivalent. The com­pany plans to run a 14-rig program in 2010.

Continental Resources Inc., Enid, Oklahoma, is the largest leaseholder in the U.S. Bakken, with 650,000 net acres. The company has been approved for drilling four wells from a single ECO-Pad with no setback from the property line. This concept lessens environmental impact, re­duces drilling and com­pletion costs by an estimated 10%, and allows 5% longer horizontals. The company has drilled several horizontal Three Forks-Sanish wells with IPs of 700 to 1,260 BOE per day, and has begun dual-zone development.

Whiting Petroleum Corp., Denver, holds 88,000 net acres primarily in Sanish and Parshall fields. Its 2008 to 2009 average IP was 2,080 BOE per day (on 24-hour tests) with EURs ranging from 570,000 to nearly 700,000 BOE, and well costs of $5.5 million. Whiting has also begun to test dual-zone development of the Middle Bakken and Three Forks.

Brigham Exploration Corp., Austin, holds 287,700-plus net acres in the U.S. Williston Basin. The com­pany has pioneered the use of 20-plus isolated frac stages, the plug-and-perf process, and ceramic proppants. Brigham’s last 10 long-lateral, high-frac-stage Bakken and Three Forks wells have averaged an early peak production rate of 2,240 BOE per day. The company’s first Three Forks well had an IP of 892 barrels equivalent per day.

Canadian Bakken players

Crescent Point Energy Corp., Calgary, holds more than 800 net sections in the Canadian portion of the Williston Basin Bakken play. It produces more than 28,000 BOE per day out of its core area in the southern portion of Saskatchewan with more than 540 active wells. The play in Canada is at half the depth of its U.S. equivalent, and well costs are half of U.S.-side costs.

PetroBakken Energy Ltd., Calgary, holds more than 210,000 net un­developed acres in the Canadian portion of the Bakken trend. It produces more than 27,000 BOE per day out of its core area in the southern portion of Saskatchewan with upwards of 500 active wells.

Bobby Stillwell and Tim Pish, Scotia Waterous, 713-222-0546