Elm Coulee Oil Field
|Current production of oil||53,000 barrels per day (~2.6×106 t/a)|
|Producing formations||Bakken formation|
Elm Coulee Oil Field was discovered in the Williston Basin in Richland County, eastern Montana, in 2000. It produces oil from the Bakken formation and, as of 2007, is the "highest-producing onshore field found in the lower 48 states in the past 56 years." By 2007, the field had become one of the 20 largest oil fields in the United States.
Geologist and independent oil man Richard Findley realized that the dolomitic middle Bakken member often had oil shows. He found a large area that showed promise; the area was too large for small operator like Findley, so he convinced Lyco Energy Resources to fund the project. A number of wells had drilled through the Bakken in Findley's project area, but had not tried to extract oil from it. Lyco re-entered nine old wells and completed them in the Bakken formation; the results were mixed, but showed that the middle Bakken had producible oil. In May 2000, Lyco drilled a well 500 feet laterally in the Bakken, hydraulically fractured it, and the well flowed 196 barrels of oil per day.
The field exploits horizontal drilling technology by perforating the productive rocks parallel to the beds, rather than through a vertical well perpendicular to the relatively thin Bakken formation. At Elm Coulee Field, the Bakken is only about 45 feet (15 m) thick and lies at depths of 8,500 to 10,500 feet (2,600–3,200 m), but horizontal wells penetrate 3,000 to 5,000 feet (900–1,500 m) of the reservoir rock, a porous dolomite of Devonian age that probably originated as a large carbonate bank on the western flank of the basin. The field is a stratigraphic trap.
In 2006, Elm Coulee was producing about 53,000 barrels (8,400 m3) of oil per day from more than 350 wells. Ultimate production is expected to exceed 270 million barrels (43,000,000 m3), with some estimates as high as 500 million barrels (79,000,000 m3). Production at Elm Coulee has more than doubled the oil output of the state of Montana, from around 40,000 barrels per day (6,400 m3/d) in 2000 to almost 100,000 barrels per day (16,000 m3/d) in 2006. However, Montana production fell again starting in 2007, down to some 70,000 barrels per day (11,000 m3/d) in mid-2009.
- "Elm Coulee". Geographic Names Information System, U.S. Geological Survey.
- Wall Street Journal, quoted in Big Sky Business Journal.
- Petroleum Technology Transfer Council Newsletter, Vol. 9, 2006.
- Energy Information Administration list of top 100 oil fields (link malfunction).
- Sourcing an oil boom, GeoExPro.
- Elm Coulee Field, Middle Bakken Member, by Bill Walker, Al Powell, Dick Rollins, and Ron Shaffer, 2006.
- Elm Coulee Field.
- USGS estimates of Bakken oil production.
- Jennifer McKee, Montana Standard State Bureau, Dec. 2, 2007.
- Production figures for Montana by EIA