Posted by: "Michael Paulos" westseattlemike@yahoo.com
westseattlemike Date: Tue Feb 15, 2011 11:34 am ((PST))
Gee! Now I can stop worrying and get a good night's sleep!
On Mon Feb 14th, 2011 9:09 PM PST robert-blau@webtv.net wrote:
Glad to hear it . . .
Yellowstone Supervolcano 'Not a Portent of Doom'
The huge volcano under Yellowstone National Park has been rising at an
unprecedented rate during the past several years, according to a new
study. In the ancient past, the Yellowstone volcano produced some of the
biggest-known continental eruptions, but the recent rising doesn't mean
another doomsday eruption is looming, scientists say.
The recent rising is unprecedented for Yellowstone's caldera -- the
cauldron-shaped part of the volcano -- but it's not uncommon for other
volcanoes around the world. The new study has simply revealed a more
active caldera at Yellowstone than scientists realized. In 2004, the
caldera was swelling at 2.8 inches (7 centimeters) per year in some
parts, but the uplift has since slowed to a low of 0.2 inches (0.5 cm)
per year, according to the study, which was published in the December
edition of the journal Geophysical Research Letters.
Calderas rise just like an inflating bubble. The inflating could either
be caused by magma rising and pushing up on the caldera, or the magma
could be heating gases and hydrothermal fluids (the same fluids that
spew from Yellowstone's Old Faithful geyser) and pushing them against
the caldera, Meertens told OurAmazingPlanet. Whatever the exact
mechanism, a rising caldera is not enough to signal an eruption.
"It's not a portent of doom," said Erik Klemetti, a volcanologist at
Denison University in Granville, Ohio, who was not involved with the
study. "It seems like these restless calderas are always sort of rising
and falling, but that by itself doesn't mean it's about to erupt."
Volcanologists look at several indicators when deciding whether an
eruption is looming, Klemetti said. Warning signs typically include an
increase in earthquakes under the volcano, changes in the gases being
emitted, change in the volcano's shape, and steam and heat escaping from
the top.
Read more:
http://ow.ly/3UG7R
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