Underwater volcanism and its hydrothermal activity play an important role in marine biogeochemical cycles, especially the carbon cycle. But the nature of hydrothermal activity at 'petit-spot' volcanoes have not been revealed at all. Now, scientists reveal that petit-spot hydrothermal activity occurs on the deepest seafloor known to date and could release carbon dioxide (CO2) and methane, which may have implications for the global carbon cycle.
