noaa.gov What is a hydrothermal vent? - National Ocean Service black smokers hydrothermal vents hydrothermal vents "A hydrothermal vent forms when seawater meets hot magma" What is a hydrothermal vent? - NOAA's National Ocean Service hydrothermal vents 40 years ago hydrothermal vents hydrothermal vents black smoker hydrothermal vents hydrothermal vents hydrothermal vents hydrothermal vents hydrothermal vent hydrothermal ocean vents "A hydrothermal vent forms when seawater meets hot magma" hydrothermal vents hydrothermal vents "A hydrothermal vent forms when seawater meets hot magma" http://oceanservice.noaa.gov/facts/vents.html 40 years ago