In the end it is all about the
potential energy been developed. In this
case, the magma is building up and it is showing this by lifting at least one
thousand times as much rock as Mt St Helens at a rate of around ten feet per
year. If sustained, It will begin breaking up in the next few centuries and
become a super volcano.
More likely it will perhaps burp
a couple of times and then go back to sleep for millennia. It is likely close to the behavior of Yellowstone .
In the meantime we have something
to worry about, but not too much. There
are a number of such volcanoes and most are like Yellowstone . The others however will sometimes ruin
everyone’s day.
Rapidly Inflating Volcano Creates Growing Mystery
Andrea Mustain, OurAmazingPlanet Staff Writer
Date: 24 October 2011 Time: 10:13 AM ET
How long has this been going on? Uturuncu, a Bolivian volcano that is
inflating at an incredible rate.
Should anyone ever decide to make a show called "CSI:
Geology," a group of scientists studying a mysterious and rapidly
inflating South American volcano have got the perfect storyline.
Researchers from several universities are essentially working as geological
detectives, using a suite of tools to piece together the restive peak's past in
order to understand what it is doing now, and better diagnose what may lie
ahead.
It's a mystery they've yet to solve.
Uturuncu is a nearly 20,000-foot-high (6,000 meters) volcano in
southwest Bolivia .
Scientists recently discovered the volcano
is inflating with astonishing speed.
"I call this 'volcano forensics,' because we're using so many
different techniques to understand this phenomenon," said Oregon State
University professor Shan
de Silva, a volcanologist on the research team.
Researchers realized about five years ago that the area below and
around Uturuncu is steadily rising — blowing up like a giant balloon under a
wide disc of land some 43 miles (70 kilometers) across. Satellite data
revealed the region was inflating by 1 to 2 centimeters (less than an inch)
per year and had been doing so for at least 20 years, when satellite
observations began.
"It's one of the fastest uplifting volcanic
areas on Earth," de Silva told OurAmazingPlanet."What we're
trying to do is understand why there is this rapid inflation, and from there
we'll try to understand what it's going to lead to."
The peak is perched like a party hat at the center of the
inflating area. "It's very circular. It's like a big bull's-eye,"
said Jonathan Perkins, a graduate student at the University ofCalifornia, Santa Cruz, who recently presented
work on the mountain at this year's Geological Society of America meeting
in Minneapolis.
Scientists figured out from the inflation rate that the pocket of magma
beneath the volcano was growing by about 27 cubic feet (1 cubic meter)
per second.
"That's about 10 times faster than the standard rate of magma
chamber growth you see for large volcanic systems," Perkins told OurAmazingPlanet.
However, no need to flee just yet, the scientists said.
"It's not a volcano that we think is going to erupt at any moment,
but it certainly is interesting, because the area was thought to be essentially
dead," de Silva said.
Sunset at Uturuncu.
Uber-Uturuncu?
Uturuncu is surrounded by one of the most dense concentrations of
supervolcanoes on the planet, all of which fell silent some 1 million years
ago.
Supervolcanoes get their name because they erupt with such power that
they typically spew out 1,000 times more material, in sheer volume, than
a volcano
like Mount St. Helens. Modern human civilization has never witnessed such
an event. The planet's most recent supervolcanic eruption happened about
74,000 years ago in Indonesia .
"These eruptions are thought to have not only a local and regional
impact, but potentially a global impact," de Silva said.
Uturuncu itself is in the same class as Mount St. Helens in Washington
state, but its aggressive rise could indicate that a new supervolcano
is on the way. Or not.
De Silva said it appears that local volcanoes hoard magma for about
300,000 years before they blow — and Uturuncu last erupted about 300,000 years
ago.
"So that's why it's important to know how long this has been going
on," he said.
To find an answer, scientists needed data that stretch back thousands
of years — but they had only 20 years of satellite data.
Jonathan Perkins, along with his advisor, Noah Finnegan (he's behind
the camera), conduct field work in the barren landscape surrounding the
volcano.
CREDIT: Noah Finnegan
CREDIT: Noah Finnegan
Volcano rap sheet
"So that's where we come in as geomorphologists — to look for
clues in the landscape to learn about the long-term topographic evolution of
the volcano," Perkins said.
Perkins and colleagues used ancient
lakes, now largely dry, along the volcano's flanks to hunt for signs of
rising action.
"Lakes are great, because waves from lakes will carve shorelines
into bedrock, which make lines," Perkins said.
If the angle of those lines shifted over thousands of years — if
the summit of the mountain rose, it would gradually lift one side of the lake —
it would indicate the peak had been rising for quite some time, or at least
provide a better idea of when the movement began.
The local conditions, largely untouched by erosion or the reach of lush
plant and animal life, lend themselves to geological detective work, Perkins
noted.
"It's a really sparse,
otherworldly landscape," Perkins said. "Everything is so well
preserved. There's no biology to get in the way of your observations."
Perkins said that surveys conducted on the lakes last autumn didn't
indicate long-term inflation. However, tilting lakes are only one indicator of
volcano growth, he said.
De Silva said the geological detective team is working to combine data
from a number of sources — seismic data, GPS data, even minute variations in
gravity — to pin down when and why the mountain awoke from its
300,000-year-long slumber, and better predict its next big move.
This story was provided by OurAmazingPlanet, a sister site to
LiveScience. You can follow OurAmazingPlanet staff writer Andrea Mustain on
Twitter: @andreamustain.
Follow OurAmazingPlanet for the latest in Earth science and exploration news on
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