Abiogenic petroleum origin
Abiogenic petroleum origin is a term used to describe a number of different hypotheses which propose that petroleum and natural gas are formed by inorganic means rather than by the decomposition of organisms. The two principal abiogenic petroleum hypotheses, proposing that all petroleum is abiogenic, the deep gas hypothesis of Thomas Gold and the deep abiotic petroleum hypothesis, have been scientifically reviewed and largely rejected.Earlier studies of mantle-derived rocks from many places have shown that hydrocarbons from the mantle region can be found widely around the globe. However, the content of such hydrocarbons in such rocks are extremely low and seem to lack accumulation in concentrations that would render them feasible for exploitation. Scientific consensus on the origin of oil and gas is that all natural oil and gas deposits on Earth are fossil fuels and are, therefore, biogenic.