Surveyors find vast undersea mountain in Arctic depths

[megman]

Canadian and U.S. scientists mapping the Arctic Ocean sea floor to bolster potential territorial claims have made a "remarkable" geological discovery: a previously unknown, underwater mountain peak rising more than a kilometre above the surrounding seabed.

The Aug. 25 discovery of the 1,100-metre-high "seamount" — along with what appears to be an extinct volcano buried in sediments nearby — is being hailed as a "significant" scientific bonus on top of promising data collected for the prime mission of proving Canada and the U.S. deserve extended jurisdiction over undersea Arctic terrain and resources.

The joint Canada-U.S. survey in waters far to the north of the Alaska-Yukon border follows a similar collaborative research expedition last summer in the Beaufort Sea.

As they did in 2008 and plan to do again next year, officials aboard the U.S. Coast Guard cutter Healy and the Canadian Coast Guard icebreaker Louis S. St-Laurent met in the southern Beaufort and travelled north to conduct surveys using sonar and scanning gear aboard the two vessels.

Officials said the sharing of specialized surveying equipment and icebreaking duties allowed each country to map a much greater area of the sea floor than if they'd been working independently.

All five nations with an Arctic Ocean coastline — Canada, the U.S., Denmark (Greenland), Norway and Russia — are working under provisions of the UN Convention on the Law of the Sea to gain control of undersea territory by identifying areas of the seabed that are linked to each country's continental shelf.

Canada's case for an extended continental shelf is due for submission to the UN in 2013.

Jacob Verhoef, the federal geophysicist leading Canada's Arctic mapping efforts, said thick sediments detected at extremely high latitudes during the latest bi-national mission appear likely to support territorial claims much farther north than either country had expected.

During a media conference on Thursday with Natural Resources Minister Lisa Raitt and U.S. oceans ambassador David Balton, scientists refrained from predicting exactly how evidence gathered during the six-week probe at the north end of the Beaufort Sea will help the countries' UN claims.

But Verhoef and his U.S. counterparts said the joint mapping operation "succeeded beyond expectations," covering hundreds of square kilometres more than the research teams had hoped they could.

They said vast areas of the northern Arctic Ocean were, for the first time, surveyed with bathymetric equipment that yields three-dimensional images of the sea floor.

It was during one of those mapping runs that U.S. and Canadian scientists aboard the Healy charted the undocumented seamount, a massive, elongated mountain ridge about 39 kilometres wide at the base and extending nearly 20 kilometres in length.

At its highest point, a plateau 1.1 kilometres above the sea floor, the mountain is still nearly three kilometres below the surface of the ocean.

The drowned mountain lies about 1,300 km north of the Yukon-Alaska border and 550 km west of Ellesmere Island. The peak doesn't appear to be part of the vast Alpha-Mendeleev underwater mountain range that stretches between Ellesmere Island and Siberia.

"What makes it remarkable," said Verhoef, "is that on this planet there are still features never seen before."

[Shirleypal]

"What makes it remarkable," said Verhoef, "is that on this planet there are still features never seen before."

You bet and of course all the things we don't know because they don't tell us.