Past Peak has a recent post on the environmental and resource constraints on the production crude oil from Canada's vast oil sands deposits. You can't just drill a hole in the ground to get this stuff. It requires huge amounts of sand and clay to be removed from the earth and processed using vast amounts of water. Then, you don't even have oil. You need to add hydrogen taken from natural gas. The scope of the resources needed is mind-boggling. It seems doubtful to me that these deposits will ever play a major role in the oil markets and over time may even become prohibative to produce for both economic and environmental reasons. For more on oil sands, a.k.a. tar sands, see my previous post on the topic.
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