Huge Underwater Volcanoes Discovered Near Antarctica

A string of a dozen volcanoes, several of them active, has been found beneath the frigid seas near Antarctica, the first such discovery in that region. Some of the peaks tower nearly 10,000 feet (3,000 meters) above the ocean floor — nearly tall enough to break the water's surface. "That's a big volcano. That's a very big volcano. If that was on land it would be quite remarkable," said Philip Leat, a vulcanologist with the British Antarctic Survey who led a seafloor mapping expedition to the region in 2007 and 2010.

The group of 12 underwater mountains lies south of the South Sandwich Islands — desolate, ice-covered volcanoes that rise above the southern Atlantic Ocean about halfway between South America and South Africa and which have erupted as recently as 2008. It's the first time such a large number of undersea volcanoes has been found together in the Antarctic region.

Leat said the survey team was somewhat surprised by the find. "We knew there were other volcanoes in the area, but we didn't go trying to find volcanoes," Leat told OurAmazingPlanet. "We just went because there was a big blank area on the map and we had no idea what was there; we just wanted to fill in the seafloor."
The team did so, thanks to ship-borne seafloor mapping technology, and not without a few hair-raising adventures. Leat said the images of the seafloor appear before your eyes on screens as the ship moves through the water. "So it's very exciting," he said. "You go along and suddenly you see the bottom start to rise up underneath you, and you don't know how shallow it's going to get."

At one point, in the dead of night, the team encountered a volcano so large it looked as though the RRS James Clark Ross, the team's research vessel, might actually crash into the hidden summit. "It was quite frightening, actually," Leat said. The researchers stopped the ship and decided to return in daylight. The onboard instruments revealed that some of the peaks rise within 160 feet (50 meters) of the ocean's surface. [Related: The World's Biggest Oceans and Seas]

Though the peaks are largely invisible without the aid of 3-D mapping technology, scientists can tell they're volcanoes. Leat said their conelike silhouette is a dead giveaway. "There's no other way of getting that shape on the seafloor," he said. In addition, the researchers dredged up rocky material from several peaks and found it rife with volcanic ash, lumps of pumice and black lava. The find backed up reports from a ship that visited the area in 1962, which indicated a hidden volcano had erupted in the region.

Leat's biologist colleagues discovered some interesting creatures living in the hot-spring-like conditionsnear the underwater mountains, and news on that will be forthcoming, Leat said. Despite the frozen, isolated conditions, Leat said the expeditions were far from boring. Quite the opposite, in fact. Each moment, a hidden world never before seen by humans unfolded before their eyes. "It's amazing," Leat said, "and you can hardly go to bed at night because you want to see what's happening."

Interesting inhabitants of the Antartic Ocean 

Ice fish

This ghostly-looking fish has no red blood cells. Glycerol in its blood acts as antifreeze, allowing the fish to stay alive in the frigid Antarctic conditions.

Basket star, Gorgonocephalus
This creature was filmed stretching out its curly, branching arms after cuddling with a coral. Posed here, above the seabed, the filter feeder can gobble food that goes floating by.

Sea Spider
Arachnophobes beware: More species of sea spider are found around Antarctica than any other place on the planet. And like many Antarctic species, the sea spiders here grow far larger than their cousins in warmer climes.

These are some progressive spiders: Males of the species carry the developing young. When birthing time arrives, the fully formed baby sea spiders crawl out of their father's leg.

Amphipod
Hello world! A brand new amphipod — a type of tiny crustacean — makes its debut. Huw Griffiths, a marine biologist with the British Antarctic Survey, says at first scientists thought the upper amphipod was a specimen of Epimeria georgiana, the species shown below. DNA barcoding revealed the two are genetically different. The new, golden amphipod has yet to be named.

Polychaete worm, Tomopteris
Some species of this type of transparent swimming worm have bioluminescence, the ability to produce light through chemical reactions.

Sea Cucumber

This cold-loving, deep-sea dweller doesn't share much with its appetizing namesake except, perhaps, an aerodynamic silhouette.

Credit: British Antarctic Survey.