A 
black smoker is a hydrothermal vent, a 
geyser on the 
ocean floor. Black smokers are known to exist in the 
Atlantic ocean and the 
Pacific ocean, at an average depth of 2100 
meters. The temperature of the hot water they vent can reach 400 
°C, which does not boil due to the high pressure at that depth. They also vent 
minerals dissolved in the water, often 
iron and 
sulfide[?], which can react to 
iron monosulfide[?], giving the geyser its distinct black color.
 History 
The first black smokers were discovered in 1977.
 Biology 
In spite of the sparse life in these depths, black smokers are the center of whole ecosystems. The heat and sulfur compounds they provide can be used by archaea, extremophile unicellular organisms. Higher lifeforms, like clams and tubeworms[?], can in turn feed on the archaea.
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