The
volcanoes are waking up and staying active. That point shouldn’t be
missed in all of this. The volcanic belts across the planets are
being energized and are becoming kinetic. This is not just volcanic
activity; this is a geological shift in planetary processes.
===Extinction
Protocol
Ecuador’s
Tungurahua volcano violently explodes: tremors felt for hundreds of
miles
At
least 200 people have been forced to leave their homes after a
volcano in Ecuador erupted and spewed ash miles into the air.
26
January, 2013
The
"strong explosion" at the Tungurahua volcano could be felt
hundreds of miles away, the Geophysics Institute reported.
It
spewed stones, gases and ash more than 5km (3.1 miles) into the sky,
authorities said.
The
clouds of ash and gas could be seen as far away as the capital Quito,
about 153km (95 miles) north of the volcano.
There
were no reported deaths, according to local media.
Authorities
declared an "orange alert", the second highest warning
level after red, following the eruption at 6.47am local time on
Sunday.
Villages
near the volcano on the eastern Andean range were evacuated, said
Lourdes Mayorga from the National Risk Management Secretariat.
Some
residents had problems leaving because of the volcanic rocks and
minor flooding following heavy rains.
After
remaining dormant for eight decades, Tungurahua - which means "throat
of fire" - rumbled back to life in 1999 and has been active ever
since.
http://www.youtube.com/watch?v=1BWosFcDleM
Volcanic
'scream' precedes explosive eruptions
By
Simon Redfern
A
change in the frequency of earthquakes may foretell explosive
volcanic eruptions, according to a new study.
BBC,
15
July, 2013
The
seismic activity changes from steady drum beats to increasingly rapid
successions of tremors.
These
blend into continuous noise which silences just before explosion.
The
study of tremors in the lead up to the 2009 eruption of Redoubt, a
volcano in Alaska, appears in Journal of Volcanology and Geothermal
Research.
Those
quakes continuously rose in pitch like a volcanic glissando - a
musical glide from one pitch to another.
Subterranean
magma plumbing systems sit beneath volcanoes and feed pressurised
molten rock toward the surface before eruptions.
As
the magma flows through deep conduits and cracks, it generates small
seismic tremors and earthquakes.
Scientists
have noted earthquakes preceding volcanic eruptions before, for
example drumbeat earthquakes were the first sign of renewed magmatic
activity in Mount St Helens in April 2005.
But
the new analysis of Alaska's Redoubt volcano shows that the tremor
glided to higher frequencies and then stopped abruptly less than a
minute before eruption.
"The
frequency of this tremor is unusually high for a volcano,"
explained Alicia Hotovec-Ellis, a doctoral student involved in the
study, from the University of Washington.
What
are the four ways volcanoes can kill?
"Because
there's less time between each earthquake, there's not enough time to
build up enough pressure for a bigger one. After the frequency glides
up to a ridiculously high frequency, it pauses and then it explodes."
The
earthquake noise sounds like a scream before eruption when the
seismometer data are speeded up sixty times to make them audible. The
authors suggest a simple model of brittle fracture may explain their
results, although the precise details of what is going on underneath
volcanoes before they erupt remain unclear.
Dr
Marie Edmonds, from the University of Cambridge, who was not involved
in the study, commented: "This work is probably the most
intensive treatment of this phenomenon. If you can get an idea of
what is causing these types of patterns then you have a route to
prediction of volcanic eruptions.
"The
question that arises is whether you can ever get these sorts of
patterns without an eruption following?
"We
had repetitive sequences of volcanic explosions in the Caribbean
island of Montserrat in 1997 and 2003 which were preceded by similar
tremors, with hybrid earthquakes that were periodic and then
recurrence intervals decreased with time before the explosion. People
are converging on a view on how magmas behave."
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