Posted on 10/11/2012 1:43:04 PM PDT by Red Badger
(Phys.org)Scientists at Scripps Institution of Oceanography at UC San Diego have used 20 years of satellite data to reveal a geological oddity unlike any seen on Earth.
At the border of Argentina, Bolivia and Chile sits the Altiplano-Puna plateau in the central Andes region, home to the largest active magma body in Earth's continental crust and known for a long history of massive volcanic eruptions. A study led by Yuri Fialko of Scripps and Jill Pearse of the Alberta Geological Survey has revealed that magma is forming a big blob in the middle of the crust, pushing up the earth's surface across an area 100 kilometers (62 miles) wide, while the surrounding area sinks, leading to a unique geological phenomenon in the shape of a Mexican hat that the researchers have described as the "sombrero uplift." Since the magma motion is happening at a great depth and at a fairly slow ratethe earth's surface rises at about a centimeter per year or roughly the rate fingernails growthere is no immediate danger of a volcanic outpouring, the researchers said. The details of the study, which was funded by the National Science Foundation, are published in the October 12 issue of the journal Science.
"It's a subtle motion, pushing up little by little every day, but it's this persistence that makes this uplift unusual. Most other magmatic systems that we know about show episodes of inflation and deflation," said Fialko, a professor of geophysics in the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics at Scripps.
The researchers have attributed the observed steady motion and sombrero-shaped deflection of the earth's surface to a large blob of magma, called a "diapir" in geological terms, forming on top of the Altiplano-Puna magma body. Diapirs have been studied using geologic records in rocks frozen many millions of years ago, but the new study is the first to identify an active magma diapir rising through the crust at present day.
Fialko said a similar uplift phenomenon is occurring near Socorro, New Mexico, but at a much lower rate.
A numerical model used to investigate a ballooning diapir in the earth's crust. Colors denote temperature. "Satellite data and computer models allowed us to make the important link between what's observed at the surface and what's happening with the magma body at depth," said Fialko. Fialko said the sombrero uplift could provide insights into the initial stages of massive magmatic events leading to the formation of large calderas. Such "super-volcano" events erupt thousands of cubic kilometers of magma into the atmosphere and can affect local and global climates.
Compared with the Icelandic volcano eruption in 2011 that spewed large amounts of ash into the atmosphere and disrupted global air travel, Fialko said, a super-volcano event would be thousands of times greater. "Those were truly disaster-type events," said Fialko. "Fortunately such events haven't happened in human history, but we know they did happen in the Altiplano-Puna area in the past."
Journal reference: Science
Provided by University of California - San Diego
Geography pops are not good
And we can always hope for the Soccoro uplift to angle the blow toward Santa Fe, Rio Arriba and Taos.
It’s not predicted for around December 21st at 11:11 PM is it?
You’re thinking of the Muslim Triangle where Argentina, Brazil and Paraguay join. It’s 2/3 of the way across the continent to the east of this giant diaper.
Send a woman there. We know what to do with diapers.
Altiplano becomes Alti-Volcano in one big bang....
is it really called a diaper?
lolz
I don’t like to panic anyone... but I had a dream a few weeks ago about massive ruptures in the earth spewing lava.
It was disturbing and I thought it was really weird at the time.
But then I forgot about it.
We were eating with our daughter and 2 1/2 year old grandson in a Chinese restaurant last weekend when his diaper suddenly got overloaded. She grabbed him and ran outside to change him and then was too embarrassed to come back in........
December 21, 2012...........or is it the 22nd?............
Look on NASA orbital schematics and you will see outlined over SE S.A. and the South Atlantic something called "SAA," the South Atlantic Anomaly, where Earth's blessed magnetic field lines strangely dip in altitude for no known reason.
The described phenomena might be a deep hot spot, a column of magma slipping under S.A. like Yellowstone or Hawai'i.
Oh, no! She was probably so glad to be going out to dinner, too!
Eet eez a beeg zeet!
12/21, 12/22, whatever it takes...
Too funny!
A planetary zit!!
Nah, we were funnin’ on the correct term that is diapir.
lol (at the sombrero) my sombrero was black, with rhinestones.
Thanks Red Badger and GeronL.
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