Sunday, September 27, 2020

Nanocrystals can trigger explosive volcanic eruptions


The presence of tiny crystals can make typically peaceful basaltic volcanoes surprisingly explosive, researchers say. Photo by Scot Nelson/Flickr

Sept. 24 (UPI) -- The presence of tiny crystals in magma can cause volcanoes to violently explode, according to a new study published Thursday in the journal Science Advances.

"Exactly what causes the sudden and violent eruption of apparently peaceful volcanoes has always been a mystery in geology research," lead researcher Danilo Di Genova said in a news release.

"Nanogeoscience research has now allowed us to find an explanation. Tiny crystal grains containing mostly iron, silicon, and aluminium are the first link in a chain of cause and effect that can end in catastrophe for people living in the vicinity of a volcano," said Di Genova, a geophysicist at the University of Bayreuth in Germany.

Using a combination of spectroscopic and electron microscopic imaging techniques, researchers were able to identify nano-sized crystals called nanolites in the ashes of active volcanoes.

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In the lab, scientists successfully demonstrated how these tiny crystals, ten thousand times thinner than a human hair, increase the viscosity of volcanic magma, preventing volcanic gasses from bubbling up, escaping and relieving pressure inside magma chambers.

For their experiments, researchers focused on magma with low levels of silicon oxide, the kind of magma that forms basalt when it cools. Low silica magma isn't very viscous; it is typically thin and runny. When low silica magma erupts, it spreads quickly.

"Basaltic volcanoes generally provide a stark contrast to their high-silica cousins, showing relatively low explosivity even if they have a high volatile content," researchers wrote in their paper.

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But the latest research suggests the presence of nanolites can turn low silica magma quite viscous, making it difficult for rising gasses to pass through it. As a result, bubbling gasses accumulate, increasing pressure in a magma chamber until the volcano explodes.

"Constant light plumes of smoke above a volcanic cone need not necessarily be interpreted as a sign of an imminent dangerous eruption," Di Genova said. "Conversely, however, the inactivity of apparently peaceful volcanoes can be deceptive."

In followup studies, researchers plan to use both computer simulations and high-pressure facilities to model the geochemical processes that result in sudden explosive eruptions.

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NANITES VOLCANOLOGY, MICROBIOLOGY IN CURRENT SF ADVENTURE NOVEL
'In The Devil Colony, released in June of 2011, Sigma faces controversy with a local Native American tribe who lay claim on ancient mummified bodies and artifacts deep in the Rocky Mountains


“From the hidden Indian treasure, to the Fort Knox secrets, to the conspiracy at the beginning of the United States The Devil Colony gives you every reason why you’ll want to be a member of Sigma Force.” (Brad Meltzer, New York Times bestselling author of The Inner Circle on The Devil Colony)

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From the Back Cover

The gruesome discovery of hundreds of mummified bodies deep in the Rocky Mountains—along with strange artifacts inscribed with an unfathomable script—stirs controversy and foments unrest. And when a riot at the dig site results in the horrible death of an anthropologist captured by television cameras, the government focuses its attention on an escaped teenage agitator—the firebrand niece of Sigma Force director Painter Crowe.

To protect her, Crowe will ignite a war across the nation's most powerful intelligence agencies. But the dark events have set in motion a frightening chain reaction: a geological meltdown that threatens the entire western half of the U.S. And the unearthed truth could topple governments, as Painter Crowe joins forces with Commander Gray Pierce to penetrate the shadowy heart of a sinister cabal that has been manipulating American history since the founding of the thirteen colonies.



About the Author

James Rollins is the author of international thrillers that have been translated into more than forty languages. His Sigma series has been lauded as one of the “top crowd pleasers” (New York Times) and one of the "hottest summer reads" (People magazine). In each novel, acclaimed for its originality, Rollins unveils unseen worlds, scientific breakthroughs, and historical secrets—and he does it all at breakneck speed and with stunning insight. He lives in the Sierra Nevada mountains.

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