Chinese researchers have discovered that the instantaneous chemical energy released by Earth's crustal activity, such as earthquakes, can serve as an "alternative fuel" to sunlight for underground microorganisms.
This latest discovery reveals an important energy source for deep -Earth ecosystems and also helps the search for potential underground life on planets such as Mars and Europa, the sixth moon of Jupiter.
The study, led by researchers from the Guangzhou Institute of Geochemistry under the auspices of the Chinese Academy of Sciences (CAS), was recently published in the journal Science Advances .
In the dark depths beyond human reach live 95 percent of Earth's prokaryotic organisms, accounting for about 19 percent of Earth's total biomass.
According to the researchers, these life forms cannot obtain organic matter synthesized through photosynthesis, and how they obtain energy has long been a mystery in the scientific community.
After simulating fault activity several kilometers underground, the research team found that when rocks fracture and create new surfaces, the newly broken chemical bonds immediately come into contact with water.
This interaction produces large amounts of hydrogen and hydrogen peroxide. This process then triggers a cycle of iron oxidation and reduction, continuously releasing electrons in the process.
These electrons then flow between elements essential for life, such as carbon, sulfur, and nitrogen, forming an invisible “underground electrical network” that provides energy for microorganisms, the research team said.
Based on the study, the researchers said that in future missions to detect life beyond Earth, it is crucial to pay special attention to looking for oxidized and reduced substances near fault zones, which could be crucial conditions for the existence of life.
