", 8 June 2014 (UTC) 

 :::::::::I'm very tired of this debate, too, but Sunray is correct, ""...dense and extremely viscous form of petroleum... referred to as bitumen or colloquially tar..."" pretty much defines it. Since this is a generic article on ""oil sands"", rather than ""Athabasca oil sands"" or ""Canadian oil sands"", I would have to change that to ""...extra-heavy oil, bitumen, or colloquially tar..."" The Venezuelan government has the largest oil reserves in the world in the Orinoco oil sands, but they call it ""extra-heavy oil"" which is technically correct since it is not bitumen but is heavier than ""heavy oil"". Canada probably produces more ""extra-heavy oil"" than Venezuela does, but there is no such category in Canada. If someone finds extra-heavy oil in a designated ""oil sands"" area, the governments deem it to be ""bitumen"", and if they find it outside they deem it to be ""heavy oil"". It's completely arbitrary. Husky Energy produces ""bitumen"" in the Cold Lake oil sands, but  then ships it to Lloydminster via a heated pipeline and feeds into its Lloydminster heavy oil upgrader. Is there any difference between Cold Lake bitumen and Lloydminster heavy oil? Not really, a chemical analysis on both is about the same. It's just that the Cold Lake oil is colder and the Lloydminster oil is hotter. It goes through the same upgrader and then is blended with about 17 other different kinds of oil to make the benchmark crude oil Western Canadian Select (WCS), which is deemed by Canadian and American authorities to be a ""conventional heavy oil"".  Unconventional is the new conventional in the Canadian oil industry.   16:15"