Last night I came across a BBC article showing that a team of UK scientists have discovered a field off hydrothermal vents almost 5 km below the ocean surface in the Cayman Trough, part of the Caribbean Sea.
These hydrothermal vents (often known as Black Smokers) are formed on the sea floor near plate boundaries where superheated water escapes from fissures in the Earth’s surfaces. As well as pumping out water they send out significant amounts of metals and gases, including sulfur based compounds. These nutrients have enabled communities of organisms to develop, most of which are chemosynthetic, meaning that they draw their energy from chemicals rather the sun (photosynthesis) like most other organisms on the planet.
Th BBC article has some great video footage of the submersible in action, along with some of the organisms recovered, check it out.