'''Tar sands''', also called '''oil sands''', are a type of [[fossil fuel]] deposit, which has only fairly recently been considered as feasible sources of oil.
Tar sands were rebranded "oil sands" by the [[oil industry]] as part of a [[public relations]] exercise. The [[Wikipedia]] page was moved in 2008.<ref>https://en.wikipedia.org/w/index.php?title=Tar_sands&action=history</ref>
''Large'' deposits exist in [[Canada]] and [[Venezuela]], and lesser deposits have been found in [[Kazakhstan]] and [[Russia]].
The extraction of tar sands is a matter of concern due to the large carbon footprint and the local environmental damage of the process.
Tar sands are the "high hanging fruit" - requiring a ''lot'' of [[energy]] to extract and purify. Advances in [[technology]] have gradually allowed more extraction to be energetically profitable (i.e. decreased the amount of energy required to extract tar sands).