Dark Oxygen: A New Discovery in Deep Ocean Science

Dark Oxygen: A New Discovery in Deep Ocean Science

Scientists have recently reported the discovery of “dark oxygen” in the Clarion–Clipperton Zone (CCZ) of the Pacific Ocean at depths of nearly 4,000 metres. The findings, published in the journal Nature Geoscience, challenge the traditional scientific understanding that oxygen is produced only through photosynthesis in the presence of sunlight. Dark oxygen refers to oxygen generated in complete darkness on the deep-sea floor, without the involvement of plants or algae.

The discovery is associated with polymetallic nodules, which are potato-sized mineral deposits rich in manganese, nickel, cobalt, and copper scattered across the seabed. Researchers observed that these nodules can create a small electrical potential difference (around 1.5 volts) when interacting with seawater. This phenomenon, described as the “geobattery effect,” can split seawater molecules through a process similar to electrolysis, releasing oxygen and hydrogen even in the absence of sunlight.