December 18, 2009

Deepest Undersea Volcanic Eruption Caught On Video

Scientists have unveiled video footage of the deepest underwater volcanic eruption, at a site where sweltering 2,500-degree lava explodes into cold water nearly a mile below the ocean surface.

Bob Embley, a marine geologist at NOAA's Pacific Marine Environmental Laboratory in Newport, Oregon, said, "It was very exciting. We've never seen anything like that on the ocean floor."

The West Mata volcano, six miles long and four miles wide, rises one mile from the sea floor and sits 4,000 feet below the ocean's surface.

Last May, scientists on board the research ship Thomas Thompson deployed an underwater robot called Jason to get a close up on the rumbling volcano. Embley described the scene as "an underwater Fourth of July."

Researchers collected samples near the volcano that showed the seawater to be highly acidic, similar to battery or stomach acid. The lava froze almost instantly as it hit the cold sea water, causing black rock to sink to the sea floor.

Scientists also found and photographed a species of shrimp apparently thriving near the volcanic vents.

Joseph Resing, chemical oceanographer for the University of Washington, said, "Nobody would have predicted that things would have survived long enough in water that acidic. It seems like it's too harsh a condition."

The volcano is spewing a type of lava known as Boninite, which until now had only been seen in extinct volcanoes more than a million years old.

Resing, the mission's chief scientist, said, "Most of the eruptions on Earth happen underwater, and you would think by now we would have seen one. It's a very rare thing that we've never seen flowing molten lava until now."

Scientists hope deep-ocean eruptions can tell them more about how the planet recycles heat and matter at the friction points where Earth's tectonic plates meet. They also hope to learn more about how carbon dioxide and sulfur gases cycle through the ocean.

West Mata lies within the Pacific "Ring of Fire", where volcanoes are common.

In the Philippines, authorities are moving 30,000 people away from the danger zone near the erupting Mayon volcano.


Image 1: An explosion at the West Mata Volcano throws ash and rock, with molten lava glowing below. Credit: NSF/NOAA

Image 2: Shrimp congregate near the summit of West Mata Volcano, withstanding hot, acid waters. Credit: NSF/NOAA

Image 3: The orange glow of magma in an eruptive area the length of a football field along the summit. Credit: NSF/NOAA


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