Gold was a proponent of non-biological origins for oil. The ongoing formation of methane deep within basement rock by bacteria might be the source for more complex hydrocarbons. The petroleum we use daily has pretty well understood origins. Porous rock capped by a salt dome is a common structure, fault slip zones are another. The accumulations we can access are geological rarities. MOST of the oil ever generated by our planet never accumulated, but escaped because there was no geological trapping mechanism.