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Here’s a compilation from two recent articles, one entitled
“Shaky faultline raises the threat
of a super-volcano” written by
Leigh Dayton and
published in
news.com.au;
the other by Roberta Mancuso in the Australian news entitled “Super
volcanoes 'ticking time bomb'.”
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HUGE volcanoes with the potential to kill millions and trigger
catastrophic effects for life on earth are well overdue for an eruption, a
scientist says. Eruptions could be so powerful that huge amounts of rock and
ash could be flung into the atmosphere and there was a risk of tsunamis from
volcanic flows hitting the ocean. The blast
will toss hundreds of thousands of cubic kilometers of rock and ash into the
atmosphere, dwarfing the eruptions of Krakatoa,
Mount St Helens, Pinatubo and any conventional volcanic explosion of the past tens of
thousands of years.
"These super-volcanoes are potentially the
greatest hazard on Earth, the only greater threat being an asteroid impact
from space," said Ray Cas, a vulcanologist with
Monash
University
in
Melbourne. "A super volcano will definitely erupt," said Cas. "It
could be in a few, 50 or another 1000 years but sooner or later one is going
to go off."
Prof Cas, of the university's School
of
Geosciences, said super volcanoes were the largest on Earth and could be found in
Italy
,
New Zealand,
Indonesia, South America and the United States. The largest was
Indonesia
's Lake Toba, which had a crater diameter of 90km.
The last significant eruption from a super volcano, known scientifically
as a caldera, occurred 2000 years ago in
New Zealand, said Cas. The 2000-year eruption cycle of many of these volcanoes had
passed, said Cas, and vulcanologists around the globe were simply watching
and waiting for an imminent disaster. "The potential death toll could
reach the hundreds of thousands to millions," Prof Cas said.
“A super-volcanic eruption might cover an entire
continent with ash that could take decades to erode,” said vulcanologist
Stephen Self of Britain's Open University. "(Such an eruption) could result in the devastation
of world agriculture, severe disruption of food supplies and mass
starvation." http://www.theaustralian.news.com.au/common/story_page/0,5744,12717924%255E30417
,00.html
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