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Ver la versión completa : Scientists searching for deep water caves off Bermuda



SENSACIONES
29th November 2009, 18:02
BERMUDA — A team of underwater explorers is charting new territory in Bermuda's deep ocean and opening a window to the island's distant past.
Using cutting edge technology, the researchers are surveying rugged underwater cliff faces that once formed a spectacular Bermuda coastline - radically different from the one we see today.
Their primary aim is to search for a network of caves that they believe would connect the deep ocean to inland caves - like Crystal and Fantasy.
In the process they are redrawing Bermuda's underwater map and gaining amazing insight into how the island would have looked at the time of the last ice age.
"At that time Bermuda was an extremely large oval shaped island with steep cliffs dropping down into the sea," said Tom Iliffe, professor of Marine Biology at Texas A & M University.
Now submerged under more than 200 feet of water, those cliff-tops have been off limits to researchers - until now.
Mr Iliffe and his team, who have been on the island for the past few weeks, used sonar depth sounders to survey the cliffs and view them using a remote control camera, operated from the boat.
They identified numerous sites that they believe could be caves.
And they plan to return to Bermuda next summer to see them for themselves, using mixed gas rebreathers - hi-tech diving equipment that allows them to plumb depths that have previously been unreachable.
"We are looking at depths of where sea level was during the ice age, between 200 and 600 feet.
"We have mapped more than 100 miles of the edge of the platform -where it (the sea bed) goes from horizontal to vertical escarpments that drop into the deep sea."
Prof. Iliffe, who has done years of research into Bermuda's inland caves, added: "We think there are deeper systems that have yet to be explored that might connect to the interior."
Theoretically, he says, it is possible that a system of tunnels exist that could allow a diver to enter at North Rock and come out at Crystal Caves.
It is more likely, though, that the fissures in the volcano would only be large enough to facilitate the movement of much smaller organisms.
"This is very much an exploration project. We really don't know what we will find - we don't know what's out there. It has never been explored before."
Professor Iliffe's research, supported by the Bermuda Zoological Foundation, could have implications that go far beyond the search for new frontiers.

He believes some of the data they collect could fuel new theories on global climate change.
"Some of the bi product of the research is that we have created a very detailed map of the sea floor.
"We hope to get information about how sea level changed in Bermuda - particularly when it was at its very lowest limits.
"We are going to gain information on what sea level was like at the greatest extremes of climate change during the high point of the ice age about 18,000 years ago.
"We hope to learn more about what happened in the past to potentially look into the future and see the possibility for predicting future climate change."
Prof. Iliffe, who is working with RIkk Kvitek, a seafloor mapping expert from California State University, and a team of grad students on the project, developed a passion for exploring Bermuda's caves during his time working at the Bermuda Institute of Ocean Sciences.
"I've got questions that I would like to have answered. We've been looking at the inland caves for many years. This is the first chance we have had to go out in the deep water."