Theoretical origin of life: deep Earth early oxygen supply (Introduction)

by David Turell , Monday, August 08, 2022, 18:55 (628 days ago) @ David Turell

A new study of heat and rocks:

https://www.sciencedaily.com/releases/2022/08/220808085900.htm

"Scientists have shown the importance of hot temperatures in maximizing hydrogen peroxide generation from rocks during the movement of geological faults, and say it may have influenced the early evolution, and feasibly even origin, of life in hot environments on the early Earth prior to the evolution of photosynthesis.

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"The pioneering research project, led by Newcastle University's School of Natural and Environmental Sciences and published today in Nature Communications, uncovered a mechanism that can generate hydrogen peroxide from rocks during the movement of geological faults.

"While in high concentrations hydrogen peroxide can be harmful to life, it can also provide a useful source of oxygen to microbes. This additional source of oxygen may have influenced the early evolution, and feasibly even origin, of life in hot environments on the early Earth prior to the evolution of photosynthesis.

"In tectonically active regions, the movement of the Earth's crust not only generates earthquakes but riddles the subsurface with cracks and fractures lined with highly reactive rock surfaces containing many imperfections, or defects. Water can then filter down and react with these defects on the newly fractured rock.

"In the laboratory, Masters student Jordan Stone simulated these conditions by crushing granite, basalt and peridotite -- rock types that would have been present in the early Earth's crust. These were then added to water under well controlled oxygen-free conditions at varying temperatures.

"The experiments demonstrated that substantial amounts of hydrogen peroxide -- and as a result, potentially oxygen -- was only generated at temperatures close to the boiling point of water. Importantly, the temperature of hydrogen peroxide formation overlaps the growth ranges of some of the most heat-loving microbes on Earth called hyperthermophiles, including evolutionary ancient oxygen-using microbes near the root of the Universal Tree of Life.

"Lead author Jordan Stone, who conducted this research as part of his MRes in Environmental Geoscience, said: "While previous research has suggested that small amounts of hydrogen peroxide and other oxidants can be formed by stressing or crushing of rocks in the absence of oxygen, this is the first study to show the vital importance of hot temperatures in maximising hydrogen peroxide generation.'"

Comment: we know the deep Earth contains extremophiles from deep core studies in mines and under the oceans. This adds to the possibilities of how life started beside deep sea hot vents theory