I don't have that good an answer for you.
IIRC, from beginning to end, exploration, drilling, transport, and refining, in it's heyday post WWII oil was a ten to one net energy gain. For every ten barrels produced, one was used in it's procurement and refinement.
Now, it's about 5-1, with slant drilling, water pumping, and advanced catalytic cracking to get more from the crude, and to use lower grades of crude.
It's my understanding that the Wyoming tar-sand and Canadian Shale deposits would be about a 3-1 prospect in terms of energy gain. However, they'd make up for it in sheer volume, being at least 100 years supply, with the current rate of growth factored in.
