Seafloor massive sulfide deposits
Seafloor massive sulfide deposits or SMS deposits, are modern equivalents of ancient volcanogenic massive sulfide ore deposits or VMS deposits. The term has been coined by mineral explorers to differentiate the modern deposit from the ancient.
SMS deposits were first recognized during the exploration of the deep oceans and the mid ocean ridge spreading centers in the early 1960s. Deep ocean bathyspheres and remote operated vehicles have visited and taken samples of black smoker chimneys, and it has been long recognised that such chimneys contain appreciable grades of Cu, Pb, Zn, Ag, Au and other trace metals.
SMS deposits are currently forming in the deep ocean around submarine volcanic arcs, where hydrothermal vents exhale sulfide-rich mineralising fluids into the ocean.
SMS deposits are laterally extensive and consist of a central vent mound around the area where the hydrothermal circulation exits, with a wide apron of unconsolidated sulfide silt or ooze which precipitates upon the seafloor.
Economic extraction of SMS deposits is in the theoretical stage, the greatest complication being the extreme water depths at which these deposits are forming. However, apparent vast areas of the peripheral areas of these black smoker zones contain a sulfide ooze which could, theoretically, be vacuumed up off the seafloor. Nautilus Minerals Inc. (Nautilus) is engaged in commercially exploring the ocean floor for copper, gold, silver and zinc seafloor massive sulphide (SMS) deposits, and mineral extraction from an SMS system. Nautilus' Solwara 1 Project located at 1600 metres water depth in the Bismarck Sea, Papua New Guinea, will be the world’s first deep-sea mining project, with first production expected in 2017.
Known SMS deposits
Deep ocean drilling, seismic bathymetry surveys and mineral exploration deep sea drilling has delineated several areas worldwide with potentially economically viable SMS deposits, including:
- Kermadec Volcanic Arc
- Colville Ridge
- Bismarck Sea
- Okinawa Trough
- Lau Basin
- North Fiji Basin
- Red Sea
List of confirmed SMS: "Mining of deep-sea seafloor massive sulfides: A review of the deposits, their benthic communities, impacts from mining, regulatory frameworks and management strategies". Ocean & Coastal Management 84: 54–67. doi:10.1016/j.ocecoaman.2013.07.005.
- "Solwara 1 Project – High Grade Copper and Gold". Nautilus Minerals Inc. 2010. Retrieved 14 September 2010.
- Hill, Matthew (2010-09-07). "Nautilus says could start undersea mining in 2013". Mining Weekly. Retrieved 14 September 2010.
- The dawn of deep ocean mining, Steven Scott, Feb. 2006
- Bertram C., A. Krätschell, K. O'Brien, W. Brückmann, A. Proelss, K. Rehdanz (2011). Metalliferous sediments in the Atlantis II deep -Assessing the geological and economic resource potential and legal constraints. Resources Policy 36(2011), 315-329.