A comment on page 16 at www.bishop-hill.net/blog/2013/8/20/more-kahya.html makes the point that practically all oil and gas that has ever been drilled had bituminous shales as the source rock. One of the exceptions is coalbed methane. The reason is that dark shales (which includes coal) are just about the only rocks that contain large amounts of organics. In that sense all oil is shale oil. The new thing is that now it is possible to get oil out of shale directly rather than looking for the rare geologic coincidences that have first cooked the oil out of the shales (without heating it enough to destroy it) and then caught the migrating oil in some kind of trap that prevented it from leaking to the surface and evaporating. In a way this is like discovering that you can actually get iron from ore instead of searching for meteoric iron.
This is an interesting comment as Velikovsky thought oil might have an extraterrestrial origin – something not many Velikovskians tend to mention. He did envisage great landscape fires that involved the burning of oil on the surface. An airburst explosion over the Near and Middle East could have ignited some of the oil the region is now famous for – presumably some of which leaked to the surface. While this tends to negate the Velikovskian origin of oil and bitumin it does allow us at the same time to visualise how an airburst might be somewhat more destructive in an oil region.