Submarine Volcano

A submarine volcano is an underwater vent or fissure in the surface of the Earth through which magma can erupt. Submarine volcanoes are especially common near tectonic plate boundaries, and mid ocean ridges alone are thought to produce roughly three quarters of all the magma that reaches the surface of the Earth. Scientists estimate that more than a million submarine volcanoes exist across the world oceans, though the great majority are no longer active; about seventy five thousand rise more than a kilometer above the surrounding seafloor, and only around 119 are known to have erupted within the last 11,700 years.