also, here is an article discussing the potential in Alberta's tar sands. One passage is especially evocative:
Using current technology and at today's oil prices, only about 20% of the Alberta's oil sands can be mined this way and even that at an enormous cost to the surrounding area. The majority of the sands are located in deeper layers, 75 yards and below, and can be recovered by a different method without removing tons of ground or the sand itself. The method entails either heating or diluting the bitumen, making it liquid enough to accumulate in a well and then be pumped to the surface. However, this technique poses severe groundwater contamination problems due to leakage of the diluting materials.It's nice to see analysts actually talking about the EROEI (energy return on energy invested) concept, rather than hiding behind promo language like "huge oil reserves" and so on.
The main drawback of oil sands is that the energy required for both extraction methods is so huge as to offset the amount of energy the extracted oil ultimately yields. The many trucks, shovels and other heavy equipment needed to remove tons of ground -- enough to fill Yankee Stadium every two days -- in order to expose the oil sands and then haul the sands away to upgrading plants for processing consume lots of energy. The reclamation process required to return the mined area to its natural state requires no less energy.