for National Geographic News
Marine scientists surveying an unexplored mountain range deep beneath the Arctic Ocean have discovered at least nine hydrothermal vents on the Gakkel Ridge, a mid-ocean mountain range that snakes for 1,100 miles (1,770 kilometers) from high above Greenland to Siberia.
Scientists say the underwater hotspots may potentially host unique forms of life previously unknown to science.
"To find as many [hydrothermal vents] as we did was completely unexpected and incredibly exciting," said Henrietta Edmonds, a marine scientist at the University of Texas at Austin and one of the lead researchers that made the discovery. "At first it was difficult to believe, but I soon managed to convince my colleagues."
Scientists have long theorized that only a few vents existed on the ridge and would be difficult to locate.
Edmonds joined a nine-week expedition aboard the US icebreaker Healy and German research vessel Polarstern to map and dredge rocks from the Gakkel Ridge.
To search for the vents, Edmonds attached a recording deviceknown as a miniature autonomous plume recorderto steel cables used by other scientists on the research trip to lower instruments to the seafloor to dredge rocks.
The recording device used by Edmonds measures depth, ocean temperature, and the concentration of suspended particulate matter in the water. Scientists plot such data to identify the signature of a hydrothermal plumea geothermal phenomenon that indicates the presence of an underwater vent.
"Much like the smoke coming out of a house chimney, hydrothermal plumes rise above and spread away from hydrothermal vents, and are much easier to find than an individual vent field," said Edmonds.
By collecting a wide sample of measurements from an area and comparing them, scientists are able to zoom in on the location of vents, which are identified by a high degree of light scattering and warm temperatures.
In addition, the scientists dredged up a fresh sulfide chimney from the ocean floor, which is an indication of active venting.
Edmonds and her colleagues reported their findings in the January 16 issue of the journal Nature.
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