MORE FROM THIS SOURCE — NATURE:
https://www.nature.com/articles/news.2008.542
[EXCERPT]
Undersea thermal vents can yield unexpected bounty: natural gas and the building blocks of oil products. In a new analysis of Lost City, a hydrothermal field in the mid-Atlantic, researchers have found that these organic molecules are being created through inorganic processes, rather than the more typical decomposition of once-living material.
Most of the planet’s oil and natural gas deposits were created when decomposing biological matter is ‘cooked’ in high temperatures underground. But non-biological hydrocarbons have also been found deep inside the Earth, where chemical processes create the molecules from inorganic sources such as rock.
Although researchers have seen some evidence for inorganic production of hydrogen in the ocean, Lost City ?is the first really clear example of a marine, deep-sea world where hydrocarbons are being synthesized abiotically,? says Giora Proskurowski of the Woods Hole Oceanographic Institution in Massachusetts, one of the researchers who made the discovery.
The Lost City hydrothermal vents, some of which are 60 metres tall, sit above magnesium- and iron-rich deposits called ‘ultramafic’ rock. The minerals contained in the rocks interact with water to produce an environment with plentiful hydrogen, making it chemically favourable for the creation of the hydrocarbon molecules that make up oil and gas.
The production of hydrocarbons is meaningless. The ONLY question with whether fossil fuels are really from prehistoric life is where is the carbon coming from. To be clear: Producing hydrocarbons out of carbon does increase the amount of energy that can be extracted; that’s why natural gas is “greener” than coal. But if the hydrocarbons are made from coal, they are still fossil fuels.
I see the researchers were from Woods Hole Oceanographic, a group which had previously been investigating abiogenic origins of oil in other locations.