• Although hydrothermal vents have been a wonder of the ocean's floor for thousands--if not millions--of years, they have only recently been brought to the attention of humans. Hydrothermal vents spew mineral-rich water into the ocean, creating new habitats for organisms that often cannot exist in other areas of the ocean. Two types of hydrothermal vents, black smokers and white smokers, have been discovered.
  
  

Black Smokers

• Black smokers are the hotter of the hydrothermal vents, reaching temperatures up to 750 F. They constantly spew out iron and sulfides into the cool ocean water, which appear to humans as a smoke-like substance. Black smokers form chimney structures from which the hot water flows. These chimneys, formed from the mineral deposits in the vented water, often grow up to 10 m in height. The structures, which are not static, grow continuously as long as the vent remains active, eventually collapsing when they reach a height where structural support is lost.
  
  

White Smokers

• White smokers give off cooler water than black smokers and usually form much smaller structures on the ocean floor. These vents give off minerals with a white smoke appearance, because white smoker emissions do not contain the metals found in black smoker emissions. Water leaving white smokers is very acidic due to the particular mineral deposits it contains.
  
  

Discovery

• Hydrothermal vents were first discovered only in 1977. A team from Woods Hole Oceanographic Institute, aboard a three-person submarine operating at a depth of 8,000 feet, was the first to discover a hydrothermal vent. This vent was discovered in the Pacific Ocean.
  
  Although vents located on the bottom of the ocean might seem like a difficult vacation spot, people can experience the same phenomenon in the form of geysers, which spew the same contents as hydrothermal vents. Geysers, though, are found on land and vent their emissions into air instead of water.