How can the 'abiogenic oil' hypothesis be disproven?

Question

We do know that complex hydrocarbons (e.g., tholins) exist in the outer Solar System. Some geologists maintain that at least some oil on Earth is of non-biological origin. The mainstream, though, tends to discount their views. Is it possible to verify the hypothesis empirically and what should we look for in geodata to have it substantiated or disproven?

Answer 1

Our current understanding of petroleum formation involves biomass (mostly dead plankton) accumulating on the seafloor, which is then buried by sediment which lithifies into shale, and the increasing pressure in an anoxic environment causes the biomass to first turn into kerogen, and then into petroleum. As such, evidence for the abiotic oil hypothesis could consist of petroleum discovered in locations inconsistent with formation in the manner discussed above. For instance, petroleum discovered within igneous or metamorphic rock, petroleum discovered within rocks older than the evolution of plankton, and so on. Additionally, the hypothesis could become more plausible if chemists discovered a method for petroleum to be synthesized from inorganic materials, and if such a process was observed in the present day.