Discover the source of methane emissions on the ocean floor

Mohammad ALHADDAD

WASHINGTON (Reuters) - A new study by researchers at the Woods Hole Oceanographic Institution (WHOI) in the United States has provided evidence of an abundance of non-bio-methane on Earth. Non-bio-methane is formed by chemical reactions that do not require organic matter.

The study, published August 19 in the Proceedings of the National Academy of Sciences, shows how gases can have an origin similar to those on other planets and moons, even those that no longer have liquid water.

In the deep sea
Researchers have long observed methane release from deep sea vents, but while gas is abundant in the atmosphere where organisms are produced, the source of methane on the seabed has been a mystery.

Geoffrey Seewald, a geochemist who specializes in hydrothermal systems at the Woods Hole Oceanographic Institution and one of the authors, says identifying the non-biological source of deep-sea methane has been a problem that scientists have tackled for years.

In the study, the researchers analyzed 160 rock samples brought from all over the world's oceans and open seas. The results showed that most of these rock samples contained pockets of methane. These oceanic deposits form a reservoir that exceeds the amount of methane in the Earth's atmosphere in the pre-industrial period.

“We were quite surprised to find this huge amount of non-bio-methane in the oceanic crust and the ocean floor mantle,” says marine geology researcher at the Woods Hole Oceanographic Institute and lead author of the study, Friedrich Klein, according to the press release attached to the study.

Extraterrestrial life
Scientists analyzed rocks using the Raman Spectrometer, a laser-based microscope that allows researchers to identify fluids and minerals in a thin layer of rock. According to the results of the analysis, almost every rock sample contained a group of minerals and gases formed when sea water is captured, which moves in the olivine mineral "olivine" through the deep ocean crust.

When the olefin cools, the water trapped inside it undergoes a chemical reaction in a process called "serpentinite" in which the rock of granular sedimentary origin turns into a transformed rock that releases hydrogen and methane.

The study proves that in extreme environments, there are only two components that can form methane, namely water and olefin.

Researchers believe that deep-sea methane could have played an important role in the development of primitive organisms living in thermal seabeds on the seabed. Elsewhere in the solar system, such as Jupiter's Europa and Enceladus around Saturn, methane produced through the process itself can provide an energy source for basic life forms.