What they mine out of tar sands/shales is bitumen. You can't pump asphalt, so they actually have to add a solvent to make it pumpable, usually naptha, which the

What they mine out of tar sands/shales is bitumen. You can't pump asphalt, so they actually have to add a solvent to make it pumpable, usually naptha, which they then have to ship to the head end - meaning you end up with 2 pipelines. This idea makes the petroleum product more like coal, which has an extensive and cost-effective rail infrastructure for transport.