Athabasca oil sands
The Athabasca Oil Sands (or "Tar Sands") is a large deposit of tar sands in north-western Canada located mainly in the province of Alberta and, to a much lesser degree Saskatchewan. Oil sand comprises bitumen (petroleum that is predominantly high molecular-weight hydrocarbons), silica sand, clay minerals, and water. Bitumen is recovered from surface-mineable oil sands by variations of the Clark water-based extraction process, which separates aerated bitumen from the other oil sand components in gravity settling vessels. In-situ methods extract bitumen from deep deposits by injecting steam to reduce the bitumen viscosity so that it can be pumped out of a well. Refining converts the molasses-like bitumen into conventional light sweet crude oil. Residual water, sand, and clays are reclaimed in mined-out areas, capped with overburden topsoil and revegetated.
Synthetic crude production from oil sands is more energy intensive and has a larger environmental footprint than conventional crude oil production. In particular, such production makes heavy use of water. In-situ processes inject water into the deposit, and surface operations produce tailing deposits and process water inventories that must be impounded, because organic compunds released during processing are toxic until degraded by natural bioloigcal processes that take years. As conventional sources of oil are depleted, non-conventional sources of oil will increasingly be relied upon to make up the difference. Environmental impacts from tar sands oil fields will grow in direct relation to the expected increase of production over the next 20 years.
Estimated size
It is estimated that the Athabasca Oil Sands deposit contains 1.6 trillion barrels (250 km3) of crude; however, at current market prices, and given the technology of today only 311 billion barrels (49.4 km3) of crude oil can be feasibly extracted. According to the Alberta Department of Energy, 882,500 barrels (140,300 m3) per day was extracted from the Alberta Oilsands in 2003. Proven reserves stand at 174 billion barrels (27.7 km3); however, it is a widely held opinion in the industry that there is far more crude than the proven reserves would suggest. By 2010 production from the Alberta Oilsands is expected to represent 10% of North America's oil production.
Although not proven, and not even considered within the oil industry, according to the Alberta Energy and Utilities Board, the Athabasca tar sands is the largest oil deposit in the world, with a claimed estimation of 1.6 trillion barrels (250 km3) of oil, of which at most 315 billion barrels (50.1 km3) are claimed to be recoverable by the oil companies given current technology. Syncrude, one of the oil companies involved in mining the tar sands, states that the entire tar sand deposit is twice the size of Lake Ontario. It is estimated the Venezuelan Orinoco tar sands deposit is slightly larger than Athabasca (see tar sands article). See [1] for more accurate estimations of about 174.5 billion barrels (28 km3).
The Athabasca Oil Sands deposit is primarily located in and around Fort McMurray, an area that has only recently been heavily explored.
Alberta has huge deposits of oil bearing sands that underlie 140,800 square kilometres (54,360 square miles) of the province. These deposits are separated into three regions: Athabasca (Fort McMurray area), Peace River and Cold Lake on the Saskatchewan border.
Oil Sand Companies
The two largest oil sands mining operations are Syncrude Canada Limited and Suncor Energy. Albian_Sands is another smaller project owned by Shell Oil.
External links
- Athabasca Info
- Map of the Athabasca Tar Sands superimposed on map of Alberta
- University of Alberta FAQ on oil sands
- The Trillion-Barrel Tar Pit - article from December 2004 Wired.
- [2]
