Tuesday, 3 July 2018

Active volcano heat source discovered under fastest-moving and melting glacier in Antarctica


Scientists have discovered active volcano heat source under Antartica's fastest-moving and melting glacier - Pine Island Glacier. The surprising find, published recently in Nature Communications, offers insight into the movement and melting of the Pine Island Glacier. The researchers first noted the volcanic activity in 2007 and verified its existence again in 2014.

A researcher from the University of Rhode Island’s Graduate School of Oceanography (GSO) and five other scientists have discovered an active volcanic heat source beneath the Pine Island Glacier in Antarctica.

Assistant Professor Brice Loose of Newport, a chemical oceanographer at GSO and the lead author, said the paper is based on research conducted during a major expedition in 2014 to Antarctica led by scientists from the United Kingdom. They worked aboard an icebreaker, the RRS James Clark Ross, from January to March, Antarctica’s summer.

"We were looking to better understand the role of the ocean in melting the ice shelf," Loose said. "I was sampling the water for five different noble gases, including helium and xenon. Helium-3, the gas that indicates volcanism, is one of the suite of gases that we obtain from this tracing method."

"We weren’t looking for volcanism, we were using these gases to trace other actions," he said. "When we first started seeing high concentrations of helium-3, we thought we had a cluster of bad or suspicious data."

The West Antarctic Ice Sheet lies atop a major volcanic rift system, but there had been no evidence of current magmatic activity, the URI scientist said. The last such activity was 2 200 years ago, he said. And while volcanic heat can be traced to dormant volcanoes, what the scientists found at Pine Island was new.

"You can’t directly measure normal indicators of volcanism like heat and smoke because the volcanic rift is below many kilometers of ice," Loose said

But as the team conducted its research, it found high quantities of an isotope of helium, which comes almost exclusively from the mantle, Loose said.

"When you find helium-3, it’s like a fingerprint for volcanism. We found that it is relatively abundant in the seawater at the Pine Island shelf.
https://watchers.news/2018/06/29/active-volcano-heat-source-discovered-under-fastest-moving-and-melting-glacier-in-antarctica/

[Posted at the SpookyWeather blog, July 3rd, 2018.]

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