Oil sands contain deposits of bitumen. To process bitumen, it first must be extracted from the ground. There are two extraction methods. Shallow oil sands deposits, which can be excavated from the surface, and deeper ‘in situ’ (in situ means ‘in place’, indicating that the bitumen is separated underground) deposits which require other recovery methods, such as cyclic stem stimulation and steam-assisted gravity drainage. These methods inject steam to help separate the bitumen from sand and clay and bring it to the surface. According to the Alberta Ministry of Energy, roughly two tons of oil sands must be dug up, moved and processed to produce one barrel of oil. The extracted bitumen is then separated from sand and water, which it surrounds. Before it is sent to a refinery to be upgraded into high-quality oil called ‘synthetic crude’, the bitumen must be treated. Bitumen is so heavy and thick that it will not flow unless heated or diluted with lighter hydrocarbons. At the refinery, the bitumen will be treated again and upgraded into synthetic crude. The upgrading process also generates other products, such as petroleum coke, which is either used to power the refinery or sold.
Extra-heavy oil is recorded in 219 separate deposits, some of which are different reservoirs in a single field, some are producing, and some are abandoned. The deposits are found in 30 countries and in 54 different geological basins, with 11 of the deposits being offshore and 5 partially offshore.
Alberta’s three oil sand deposits — Athabasca, Cold Lake, and Peace River — contain resources that could supply Canada’s energy needs for more than 475 years, or total world needs for up to 15 years. Syncrude claims that the production potential of all the oil sand deposits could be as high as 2.5 trillion barrels of bitumen, five times more than the conventional oil reserves in Saudi Arabia. The Athabasca deposit is twice the size of Lake Ontario.
The Athabasca Oil Sands deposit, in northern Alberta, is one of the two largest oil sands deposits in the world. There are also oil sands deposits on Melville Island, in the Canadian Arctic and two smaller deposits in northern Alberta, Peace River and Cold Lake. In 2009, production of bitumen averaged 1.49 million barrels per day, according to the Government of Alberta, compared to 461,300 barrels per day of conventional crude.
