Mining

The deep-seabed contains potentially exploitable resources, including minable methane hydrates, manganese crusts, polymetallic sulphides and polymetallic nodules. Mining these resources is technically feasible at present, but legal, environmental and economic factors are delaying any potential extraction for the next 10-20 years. Many current methods of extraction in the deep sea are similar to terrestrial strip mining, removing layers of sediment before extracting the targeted resource and discharging any by-products.

Modern extraction methods would most likely use benthic vehicles and suction extractors rather than the previously used techniques of large-scale dredging. The impacts of this technology could extend over large areas, for example, an individual mining operation for polymetallic nodules was predicted to cover 300-800 kilometres square of seafloor per year, with the impacts of sediment resuspension extending over a much larger area.