[OldEngineer]

Does geothermal energy constitute a significant percentage of oil's energy content?

If the initial energy of the biomass that becomes oil is significantly added to by the earth's heat as the biomass is cooked into oil, it seems to me that any hope for biomass renewable energy as an oil substitute is further reduced.

The high energy density of oil may be a consequence of the generation of hydrocarbons of increased complexity by geothermal heat.

[LogicMan]

There is no geothermal energy content in oil. It's all chemical energy. It's the affinity of the hydrogen and carbon in the oil for oxygen that is the key to it's energy. The geothermal heat in an oxygen free environment for millions of years has made it more useful but has not contribued to it's energy content. It's much like charcoal, that hickory log has more total energy in it than the charcoal it can be turned into, but the charcoal is more useful.