Underwater volcanoes

 Underwater Volcanoes, aka Submarine Volcanoes, are underwater volcanoes or fissures in the planet's surface from which magma can erupt. They are estimated to account for up to 75% of annual magma output. The vast majority are located near areas of tectonic plate movement. Although most are located in the ocean depths, some also exist in shallow water, which can spew material into the air during an eruption. Thermal vents, sites of abundant biological activity, are commonly found near submarine volcanoes.