tattoo empek empek: Huge underwater volcanoes found near Antarctica

Huge underwater volcanoes found near Antarctica - Seattle Post Intelligencer (blog)

Underwater volcanoes

These images of the seafloor landscape around the South Sandwich Islands, in the Southern Ocean, were captured using echo-sounder technology deployed from the Royal Research Ship James Clark Ross. The technique is known as multi-beam swath bathymetry. The area mapped is approximately 600 km long by 150 km wide – almost the length of Britain.

Newly discovered submarine volcanoes in the northern part of the South Sandwich Arc. The 'map' shows volcanoes approximately 50 metres below the sea surface. The volcano in the foreground is thought to be the most active with eruptions in the past few years. (British Antarctic Survey )

Two lines of newly discovered volcanoes surrounding Saunders Island in the South Sandwich arc. (British Antarctic Survey )

The line of underwater volcanoes – this image shows the South Sandwich Islands 'arc' very clearly. (British Antarctic Survey )

As string of massive underwater volcanoes was recently discovered near Antarctica, and some of the mountains tower as high as 10,000 feet above the ocean floor — almost tall enough to break the surface of the ocean.

"That's a big volcano," Phil Leat from the British Antarctic Survey told MSNBC. "That's a very big volcano. If that was on land it would be quite remarkable."

To put that in perspective, 10,000 feet is nearly the elevation of Mount Fuji in Japan.

The 12 volcanoes, at least some of which are active, are located near the South Sandwich Islands in the South Atlantic. That region is known for volcanic activity, but Leat said he didn't expect to find volcanoes this large.

"There is so much that we don't understand about volcanic activity beneath the sea — it's likely that volcanoes are erupting or collapsing all the time," said Leat in a statement. " The technologies that scientists can now use from ships not only give us an opportunity to piece together the story of the evolution of our earth, but they also help shed new light on the development of natural events that pose hazards for people living in more populated regions on the planet."

He told National Geographic the immensity of the underwater mountains was frightening during the expedition:

The volcanoes' immensity sometimes made the researchers' work at sea a bit scary. Two of the features rise within 225 feet (70 meters) of the surface—one in an area where existing charts showed only deep water.

"You can see the surface rising up beneath you, and you don't know how high this thing is going to be," Leat said. "You inch forward.

"But it's also very exciting, because you are discovering not just a volcano nobody knew about but a huge one."

Many of the peaks are visible from the ocean's surface, but 3-D mapping technology was used to measure the enormity of the underwater structures.

British Antarctic Survey described the effort this way:

Using ship-borne sea-floor mapping technology during research cruises onboard the RRS James Clark Ross, the scientists found 12 volcanoes beneath the sea surface — some up to 3km high. They found 5km diameter craters left by collapsing volcanoes and 7 active volcanoes visible above the sea as a chain of islands.

Visit seattlepi.com's home page for more Seattle news. Contact Amy Rolph at amyrolph@seattlepi.com or on Twitter as @amyrolph and @bigblog.