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 recognised 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
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.
Known SMS deposits
Deep ocean drilling, seismic bathymetry
surveys and mineral exploration deep sea drilling has delineated several areas... Read More