An international team of researchers has made a groundbreaking discovery: oxygen can be generated in total darkness, about 4,000 meters below the ocean surface. This surprising discovery was published in the journal Nature Geosciences Monday and challenges long-held beliefs about the origins of oxygen on Earth.
The discovery focuses on potato-shaped metallic nodules found deep in the Pacific Ocean. These nodules, found at depths of about 13,100 feet, have been shown to produce oxygen through a process that does not require sunlight, overturning the traditional understanding that photosynthesis by plants and algae is the primary source of oxygen on our planet.
Professor Andrew Sweetman, from the Scottish Association for Marine Science, led the research team. He explained: “For aerobic life to have begun on Earth, there had to be oxygen, and it was thought that this oxygen was produced exclusively by photosynthetic organisms. This new discovery shows that oxygen can be produced even in the deep sea, where light cannot penetrate. This may force us to reconsider our theories about the origins of aerobic life.”
The study also raises important questions about the environmental impact of deep-sea mining. These nodules, rich in essential minerals such as cobalt, nickel, copper and manganese, are targeted by mining companies because of their value for technologies such as electric vehicle batteries and renewable energy systems.
During their research in the Clarion-Clipperton Zone, an abyssal plain between Hawaii and Mexico, scientists found that the nodules carried a significant electrical charge. This charge can split seawater into hydrogen and oxygen through seawater electrolysis, a process previously not associated with natural environments.
Sweetman stressed the need for further research, saying, “We've raised many new questions with this discovery. It's critical to understand how mining these nodules, which act as natural batteries, might affect the deep-sea environment.”
The study was funded in part by The Metals Co., a Canadian mining company that plans to begin mining in the Clarion-Clipperton Zone by the end of 2025. Deep-sea mining involves using heavy machinery to extract valuable minerals from the ocean floor, a practice that has raised significant environmental concerns.
Environmental groups say deep-sea mining is unsustainable and poses a significant threat to marine ecosystems. Sofia Tsenikli, the Deep Sea Conservation Coalition’s global campaign manager on deep-sea mining, stressed the urgency of a moratorium on such activities. She said: “This research underscores how much we still need to learn about the deep sea. It highlights the potential risks that deep-sea mining poses to marine life and natural processes.”
This discovery adds to the growing call for caution and further study of the deep-sea environment before proceeding with potentially harmful mining operations.
