 abiogenic petroleum origin is a term used to describe a number of different theories which propose that fossil fuels are formed by inorganic means rather than by the decomposition of organisms. most abiogenic petroleum theories have been scientifically discredited and are obsolete. scientific opinion on the origin of fossil fuels is that almost all fossil fuels on earth are not abiogenic in origin. there are a few abiogenic petroleum theories which are still subject to ongoing research and which typically seek to explain the existence of smaller quantities of fossil fuels. some mostly discredited abiogenic theories have proposed that fossil fuels have originated from deep carbon deposits, present since the formation of the earth. other hypotheses have suggested that hydrocarbons may have arrived on earth from solid bodies such as comets and asteroids from the late formation of the solar system, carrying hydrocarbons with them. some abiogenic hypotheses gained limited popularity among geologists over the past several centuries. most recently, scientists in the former soviet union widely held that significant petroleum deposits could be be attributed to abiogenic origin, though this view fell out of favor toward the end of the 20th century because they did not make useful predictions for the discovery of oil deposits.  most geologists now consider the abiogenic formation of petroleum to have insufficient scientific support and hold that fossil fuels are formed almost exclusively from organic material. == history == earliest abiogenic theories in the 16th century, with considerable additional speculation regarding the origin of petroleum dating to the 18th and early part of the 19th century. at the time, the chemical nature of petroleum was not known. an abiogenic hypothesis was first proposed by georgius agricola in the 16th century and various additional abiogenic hypotheses were proposed in the 19th century, most notably by prussian geographer alexander von humboldt, the russian chemist dmitri mendeleev and the french chemist marcellin berthelot. abiogenic hypotheses were revived in the last half of the 20th century by soviet scientists who had little influence outside the soviet union because most of their research was published in russian. the hypothesis was re-defined and made p
Biological_hypotheses Extremophiles Hypothetical_processes Peak_oil Petroleum_geology