Oil Sands

Oil sands (also called tar sands) are deposits of sand and rock that contain crude bitumen — a dense, highly viscous form of crude oil. Bitumen is too thick to flow naturally and must be extracted and upgraded before it can be refined into fuels such as gasoline and jet fuel.

Where oil sands are found

• Major deposits are in northern Alberta and Saskatchewan (Canada), primarily the Athabasca, Cold Lake, and Peace River regions.
• Other occurrences exist in Venezuela, Kazakhstan, and Russia.
• Canada holds a very large share of the world’s proven oil reserves, most of which are in oil sands.

How bitumen is produced

There are two main extraction methods, chosen according to the depth and geology of the deposit:

Surface mining (open-pit)

• Used where oil sands lie near the surface.
• Operators clear vegetation, strip topsoil and overburden, and remove the oil-bearing sand with large shovels and trucks.
• The mined sand (typically 1–20% bitumen by volume) is separated, upgraded into synthetic crude, then sent to refineries.
• Surface mining requires extensive land disturbance and reclamation planning.

In‑situ recovery (solution mining)

• Used for deposits too deep for open-pit mining (an estimated ~80% of Alberta’s oil sands).
• The most common technique is steam-assisted gravity drainage (SAGD): steam (and sometimes chemicals) is injected to lower bitumen viscosity so it can be pumped to the surface.
• In‑situ operations have a smaller surface footprint than open-pit mines but still consume substantial energy and water and can involve well stimulation techniques.

Economic considerations

• Producing oil from oil sands is more expensive than conventional oil extraction; profitability is sensitive to global oil prices.
• Oil sands contribute significant revenue, investment, and employment, particularly in Alberta’s economy.

Environmental impacts

• High greenhouse-gas emissions per barrel compared with many conventional sources due to energy-intensive extraction and upgrading.
• Large-scale surface mining destroys habitat and topsoil and requires long-term reclamation; historically, only a small fraction of mined areas have been reclaimed.
• Water use and contamination risks affect local watersheds; tailings ponds and process water are persistent challenges.
• In‑situ methods reduce surface disturbance but still involve emissions, water use, and potential subsurface impacts.

Mitigation and innovation

• Industry and research groups are developing technologies to reduce emissions, improve water use and management, decrease land disturbance, and accelerate reclamation.
• Collaborative initiatives (for example, innovation alliances) fund research into lower-impact extraction, remediation techniques, and monitoring.

Key facts

• Bitumen must be extracted and upgraded before refining.
• Surface mining and in‑situ (SAGD) are the primary production methods.
• Oil sands production is capital- and energy-intensive, with significant environmental trade-offs balanced against economic benefits.

Sources: Natural Resources Canada; Canadian Association of Petroleum Producers; Oil Sands Discovery Centre; Canada’s Oil Sands Innovation Alliance.