Scientists Looking for Hydrothermal Vents off Antarctic Coast
04.03.2010 - Water & Oceans, Flora & Fauna, Antarctic
As described in the journal Geophysical Research Letters,scienetists have likely discovered new hydrothermal vents off the coast of Antarctica.
While analyzing ocean-helium measurements, scientists at Columbia University's Lamont-Doherty Earth Observatory Laboratory came across a helium plume that looked out of place in the South Pacific Ocean. Suspecting the plume to have its origins in the Pacific Antarctic Ridge - a chain of volcanic undersea mountains with steep peaks, canyons, and fracture zones where the sea floor is spreading - geochemist Gisela Winckler and colelagues compiled a detailed map of ocean-density layers in the region, covering 547 km of ridge line, or about 7% of the length of the ridge.
The hydrothermal vents, which are in a remote part of the South Pacific far from commercial shipping lanes, spew volcanically heated seawater. The chemical elements these vents contain sustain a number network of organisms very much like the sun does on the surface of the Earth. While some 220 of these vents have been found in recent decades, none has been found in the cold waters off Antarctica thus far. While they have not yet been able to find a vent, the scientists have been able to identify six possible spots on the remote Pacific Antarctic Ridge, located some 1600 km off the west coast of Antarctica.
Two indicators in particular are helping scientists pinpoint possible locations for the vents:
- places where the ocean is stratified with layers of lighter water sitting on top of layers of denser water
- places where they find helium-3, an isotope found in earth's mantle, which would be emitted from seafloor vents as they erupt
Finding vents in Antarctica is not easy, as scientists sometimes don’t find the vents they set out to look for, making the process unpredictable. Nonetheless, the map the scientists are producing should greatly improve the chances of actually finding one. These vents, of which the first were found in the late 1970s, have always interested scientists looking for new species and their adaptive patterns in an attempt to find out how species evolved in different spots.
