Trillions of polymetallic nodules are scattered across the ocean floor, containing valuable metals such as manganese, nickel, cobalt, and copper. Mining companies argue that extracting these nodules could provide the resources needed to build electric cars, wind turbines, and solar panels, which are crucial to replacing carbon-emitting technologies.
However, other researchers warn that deep-sea mining could have catastrophic consequences for the already stressed and plastic-ridden oceans. The delicate and long-living marine life that inhabits the deep sea could be obliterated by dredging, and plumes of sediments containing toxic metals could poison marine food chains.
The dispute over deep-sea mining is highly polarized, with proponents claiming it could save the world and opponents warning it could unleash fresh ecological mayhem. The Clarion-Clipperton Zone (CCZ), which covers more than 4 million square kilometers of seabed and is particularly rich in nodules, has sparked the interest of mining and dredging companies.
Despite the aeons-long accretion rate of nodules, trillions of them now cover the ocean bed. More than 20 exploration contracts have been awarded by the International Seabed Authority (ISA), the UN body responsible for controlling mining on international waters, with companies hoping to transform their exploration contracts into permits to extract the abyss’s mineral treasures and bring them to the surface.
Mining companies are exploring three key sources in the deepest parts of Earth’s oceans: hydrothermal vents, sea mounts, and polymetallic nodules. Hydrothermal vents are underwater volcanoes that spew sulphur compounds, including sulphides of silver, gold, manganese, cobalt, and zinc. Sea mounts, which are underwater peaks, are known to be rich in cobalt chemicals and have attracted the interest of mining companies.
Polymetallic nodules, which litter the bottom of the deep ocean, have shown the most interest from mining companies due to the relative ease of extraction. The Clarion-Clipperton Zone is the primary target for mining, although some companies have pinpointed other areas. For instance, Florida’s Ocean Minerals wants to mine off the Cook Islands in the Pacific.