Science believes that oil and natural gas are formed by organisms decomposing. How that process originated is the subject of the abiotic oil theory. At some point, inorganic matter had to be the foundation of the organic matter that would eventually create the fossil fuels. That transition, from inorganic to organic, is an evolutionary process referred to as “abiogenesis.”
When applied to oil and natural gas formation, that is how we get to the abiotic oil theory.
The first abiotic oil theory was proposed in the 16th century by Georgius Agricola. They continued to be promoted through the first half of the 20th century, especially within the Soviet Union. Because there is a lack of predictability in finding oil or natural gas deposits using this theory, however, it is generally rejected for the theories that involve organism decomposition.
How Could Oil and Natural Gas Form?
Several ideas that have been shared through the abiotic oil theory suggest that natural gas and petroleum have always been present on Earth. The initial deep deposits could have been formed from carbon deposits that formed during the initial period of planetary formation. Those carbon deposits could have come from asteroids, comets, or unknown special bodies that impacted the Earth during its formation.
Within the mantle of Earth, carbon has the potential of existing as hydrocarbons. It is usually found as methane, but CO2, elemental carbon, or carbonates are also possible. Within the abiotic oil theory, it is suggested that petroleum can be generated within the mantle based on abiogenic processes that incorporate this carbon.
In 2009, the Royal Institute of Technology in Stockholm reported research that suggests crude oil and natural gas can be generated outside of the decomposition of flora and fauna fossils. That finding provides support for the idea that petroleum and natural gas can form through more than one method.
How Could the Abiotic Oil Theory Work in Practical Terms?
There are 6 possible mechanisms that could support the processes described in the abiotic oil theory, creating organic matter from inorganic matter.
1. Ancient Deposits.
Crude oil and natural gas could be formed from ancient hydrocarbon deposits that have always been present on our planet. Whether it was supernaturally created or the planet formed through a natural evolutionary process, these hydrocarbons have formed into fuel over the potential of 1 billion years.
2. Mantle Creation.
The hydrocarbon mixes required in the abiotic oil theory may also be created within the natural conditions of the mantle.
3. Hydrogen Generation.
Hydrogen has been found as deep as 20,000 feet below the surface of our planet. Depths of up to 66,000 feet are possible. If hydrogen were present, it could react with water, ferrous oxide, and magnetite to produce crude oil or natural gas.
4. Serpentinite Mechanism.
Another proposed idea is that methane, hydrogen, or carbon dioxide could form petroleum with inorganic carbon when exposed to a high pressure, high temperature environment.
5. Spinel Polymerization Mechanism.
High concentrations of magnetite, ilmenite, and chromite can be found in many rocks. Although chemically reduced rocks would be required to make this mechanism work, the reaction of methane and magnetite with ethane and hematite offers the potential of producing the conditions described by the abiotic oil theory.
6. Carbonate Decomposition.
It is possible for calcium carbonate to decompose at temperatures of over 900F, or 500C. The only problem is that calcium carbonate is not a mineral found within natural rocks, so although this reaction is possible, the plausibility of this method is not practical to the implementation of the theory.
Why Is the Abiotic Theory Important to Study?
Although the origin of petroleum or natural gas seems like a strange debate to have, determining whether this fuel is a fossil fuel or not is important. If these fuels are truly fossil fuels, then they are limited in supply and alternative energy resources would need to be created at some point.
If they are not fossil fuels and are created through some form of abiogenesis, then the need to develop alternative fuels is reduced.
The fact is, however, that no one knows with absolute certainty how oil and natural gas deposits form on our planet. We do know they are not directly associated with tectonic plates and structures, but otherwise, any theory offers potential answers.
The abiotic oil theory comes in and out of preference over the years. At the moment, it may be out of favor for many, but that does not eliminate its potential validity.