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The Bakken Formation is a rock unit from the Late Devonian to Early Mississippian age occupying about of the subsurface of the Williston Basin, underlying parts of Montana, North Dakota, Saskatchewan and Manitoba. The formation was initially described by geologist J.W. Nordquist in 1953.〔Nordquist, J.W., ''Mississippian stratigraphy of northern Montana,'' Billings Geological Society, 4th Annual Field Conference Guidebook, pp. 68–82, 1953〕 The formation is entirely in the subsurface, and has no surface outcrop. It is named after Henry Bakken, a farmer in Tioga, North Dakota who owned the land where the formation was initially discovered, during drilling for oil.〔(Bakken Formation: Will it fuel Canada's oil industry? ), June 27, 2008, (cbc.ca ).〕 Besides being a widespread prolific source rock for oil when thermally mature, significant producible oil reserves exist within the Bakken formation itself.〔(US Energy Information Administration, November 2008, ''Technology-based oil and natural gas plays: Shale shock! Could there be billions in the Bakken?'' ), PDF file, retrieved 16 January 2009.〕 Oil was first discovered within the Bakken in 1951, but past efforts to produce it have faced technical difficulties. In April 2008, a USGS report estimated the amount of recoverable oil using technology readily available at the end of 2007 within the Bakken Formation at 3.0 to , with a mean of 3.65 billion. Simultaneously the state of North Dakota released a report with a lower estimate of of technically recoverable oil in the Bakken.〔(ND study: 167 billion barrels of oil in Bakken )〕 Various other estimates place the total reserves, recoverable and non-recoverable with today's technology, at up to 24 billion barrels. A recent estimate places the figure at 18 billion barrels.〔http://www.nd.gov/ndic/ic-press/bakken-form-06.pdf〕 In April 2013, the US Geological Survey released a new figure for expected ultimate recovery of 7.4 billion barrels of oil.〔US Department of the Interior, (USGS releases new oil and gas assessment for Bakken and Three Forks ), 30 Apr. 2013.〕 The application of hydraulic fracturing and horizontal drilling technologies have caused a boom in Bakken production since 2000. By the end of 2010, oil production rates had reached per day, thereby outstripping the pipeline capacity to ship oil out of the Bakken. There is some controversy over the safety of shipping it by rail. This was illustrated by the 2013 Lac-Mégantic rail disaster in which a unit train carrying 77 tank cars full of highly volatile Bakken oil through Quebec from North Dakota to the Irving Oil Refinery in New Brunswick derailed and exploded in the town centre of Lac-Mégantic, destroying 30 buildings (half the downtown core) and killing 47 people. The explosion was estimated to have a 1-kilometre (0.62 mi) blast radius.〔(National Post graphic of Lac-Megantic destruction )〕 As of January 2015, estimates varied on the break-even oil price for drilling Bakken wells. The North Dakota Department of Natural Resources estimated overall break-even to be just below US$40 per barrel. An analyst for Wood McKenzie said that the overall break-even price was US$62/barrel, but in high-productivity areas such as Sanish Field and Parshall Oil Field, the break-even price was US$38-US$40 per barrel. == Geology == The rock formation consists of three members: lower shale, middle dolomite, and upper shale. The shales were deposited in relatively deep anoxic marine conditions, and the dolomite was deposited as a coastal carbonate bank during a time of shallower, well-oxygenated water. The middle dolomite member is the principal oil reservoir, roughly two miles (3.2 km) below the surface. Both the upper and lower shale members are organic-rich marine shale. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Bakken Formation」の詳細全文を読む スポンサード リンク
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