Oilsands | Pembina Institute

Oilsands 101

This section outlines basic background facts about the oilsands in Alberta. Click each heading for more information.

For a more detailed exploration of the challenges of oilsands development, see our page Key Facts in Context.

Oilsands are found in several places around the world. Canada and Venezuela have the largest of these petroleum deposits, and Alberta’s oilsands are the most developed.1

Map of world bitumen distribution

Source: Richard F. Meyer, Emil D. Attanasi and Philip A. Freeman, “Map of Sedimentary Provinces Reporting Natural Bitumen”, plate 3 from Heavy Oil and Natural Bitumen Resources in Geological Basins of the World, U.S. Geological Survey, 2007.

Oilsand is a naturally occurring mixture of sand or clay, water and tar-like bitumen.
  • In an oilsand deposit, each grain of sand is covered by a thin layer of water and then by a layer of the highly viscous bitumen.2
  • Bitumen is a heavy form of crude oil. Like Alberta’s conventional crude oil, the bitumen probably formed millions of years ago from the remains of tiny sea creatures that lived in an ancient ocean that once covered Alberta. In the case of the oilsands, the petroleum moved upwards from where it formed and saturated large areas of sand closer to the surface. Bacteria then fed on the lighter petroleum chemicals in the oil, leaving behind only the molasses-like bitumen.3
  • Unlike conventional crude oil, bitumen is too thick and viscous to flow naturally or to be pumped out of the ground unless it is heated or diluted with a solvent.4
  • Before it can be refined like conventional crude oil, bitumen must be upgraded into synthetic crude oil. Upgrading is a process that converts heavy oil into a hydrocarbon product with a density and viscosity similar to that of light crude oil by using heat to crack big molecules into smaller ones. The upgrading process can require high temperatures, high pressure, catalysts and hydrogen; thus, energy is consumed during upgrading. 5
Oilsands and tar sands are the same thing.
  • While technically called “bituminous sands,” Alberta’s deposits were originally called “tar sands” because of their thick, sticky properties.
  • The term “oilsands” gained popularity in the mid-1990s after government and industry efforts to improve public perception of the dirty-sounding tar sands.6

Dig deeper into the oilsands:

Alberta's Oilsands Climate Impacts Water Use Tailings Reclamation Air Pollution


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