hydrothermal vents

A hydrothermal vent, also called a "black smoker", is a fissure in a planet's surface from which geothermally heated water issues. Hydrothermal vents are commonly found near volcanically active places, tectonic plates that are moving apart, ocean basins, and hotspots. Hydrothermal vents are abundant on Earth because it is both geologically active and has large amounts of water on its surface. Common land types include hot springs, fumaroles and geysers. The most famous hydrothermal vent system is probably Yellowstone National Park in the United States.Relative to the majority of the deep sea, the areas around hydrothermal vents are biologically productive, often hosting complex communities fueled by the chemicals dissolved in the vent fluids.  Chemosynthetic archaea form the base of the food chain, supporting diverse organisms, including giant tube worms, clams, and shrimp.
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