What does Hydrocarbons are not biology reworked by geology as the traditional view would hold but rather geology reworked by biology mean?

Answer 1

Hydrocarbons (petroleum, bitumen, oil, gas) can result from several processes. One of these is biogenic gas in which bacteria eat oil seeps or other hydrocarbons and produce mostly methane gas. Another example would be the Athabasca oil sands of Alberta in which bacteria ate most of the oil that migrated through this area millions of years ago and the residue is tar, rather like asphalt on a road. These would be Biology reworking geology. The primary mode of hydrocarbon generation is burial of organic-rich petroleum source rocks. Increases in temperature and pressure through time can "cook" oil and gas from these mostly shale and carbonate rocks. This is geology reworking biology. An example of an organic rich source rock that wasn't buried deep enough to generate petroleum is the oil shales of western Colorado and eastern Utah. I'm a petroleum research scientist with about 30 years experience.