Based on the geological formations that are present in Alaska (and throughout the Canadian north) conditions which rock oil is formed, suggests that there is vast amounts of oil and gas reserves waiting to be tapped into. The plus is those rock formations are closer to the surface in that region, so it's possible to drill into it. Otherwise rock oil is too deep for present drilling methods, so cracks (faults) where it seeps up into fields closer to the surface have to be found. Abiotic (rock oil) is continuously being formed deep in the earth.
The Statistical Thermodynamics of Petroleum Science