The discovery of dark oxygen in the deep ocean, particularly in the Clarion-Clipperton Zone (CCZ), has highlighted the limited knowledge we have of this environment. The CCZ is currently being explored for deep-sea mining of rare metals found in rock nodules that take millions of years to form and are crucial for emerging green technologies.
According to Sweetman, a leader in seafloor ecology and biogeochemistry, the revelation of dark oxygen has reshaped our perception of the deep sea and its potential impact on life on Earth. The finding has raised more questions than answers, prompting a new research initiative to delve deeper into this phenomenon. The primary objective of this project is to investigate whether dark oxygen production occurs in other parts of the CCZ where nodules are present and to understand the mechanisms behind its production.
Moreover, exploring dark oxygen could provide insights for space scientists seeking life beyond Earth. This unexpected discovery challenges the traditional notion that oxygen production is solely reliant on sunlight, as seen in other remote, light-deprived environments where oxygen molecules have been observed.
Research by microbiologist Emil Ruff and his team in Alberta, Canada, uncovered oxygen in groundwater samples isolated from the atmosphere for tens of thousands of years. Despite initial skepticism that the oxygen was a result of contamination, further investigation revealed that microbes in the water were producing oxygen through a unique process involving the breakdown of nitrites. This discovery not only sheds light on the resilience of microbial life but also challenges preconceived notions about oxygen production and its implications for sustaining other organisms.
Ruff’s work demonstrates the complexity of natural processes and the unexpected capabilities of microbial life forms. By studying dark oxygen in various environments, researchers aim to unravel its mysteries and expand our understanding of the interconnectedness of life on Earth.
A team of scientists is conducting a study at a 3-kilometer-deep mine in South Africa, where brines have been isolated in the rock for 1.2 billion years. These brines are full of life, prompting researchers to investigate the production of oxygen in this ancient ecosystem. Scientists are exploring how oxygen molecules in the water were formed, with two hypotheses currently being examined. One theory suggests that oxygen is produced through radiolysis, the splitting of water molecules by radioactivity, while the other hypothesis involves microbial processes similar to those found in Canadian groundwater.
The project also aims to understand if microbial reactions play a role in producing oxygen on the seafloor, particularly examining the release of hydrogen during oxygen production by metallic nodules. Collaboration between scientists is crucial to unraveling the mechanisms behind the production of dark oxygen, a process that has caught the interest of NASA in the search for extraterrestrial life.
Deep-sea mining companies are eyeing the extraction of cobalt, nickel, copper, lithium, and manganese from nodules for green technologies like solar panels and electric car batteries. However, concerns have been raised about the environmental impact of deep-sea mining, with critics warning about potential damage to the ocean ecosystem and the climate crisis.
The Metals Co. has disputed the findings published in Nature Geoscience and is undergoing peer review for their rebuttal. Despite the backlash, researchers remain confident in their work and stress the importance of understanding the seabed ecosystem before further exploitation of resources. Amy Gartman from the US Geological Survey emphasizes the need for a better understanding of the electrical phenomena in ferromanganese nodules before any actions are taken.
Up to this point, she had not participated in the research conducted by Sweetman or Ruff. “Scientists are presently attempting to reproduce the occurrences detailed by Sweetman and other researchers,” she commented. “The pursuit of scientific inquiry is a gradual process, and it could take a while before a definitive conclusion is drawn.” To access further CNN updates and newsletters, please register an account on CNN.com.
