Earthquakes,
The Fuse That Ignites Volcanoes, Have Increased Worldwide
16
December, 2012
Earthquakes
and Volcanic eruptions have always been closely related. For
instance, if you look at a map of quakes worldwide and compare it to
a map of volcanoes, you’ll find that they match closely. Both
earthquakes and volcanoes occur at the boundaries of tectonic plates,
which make up the Earth’s surface. Earthquakes are caused by the
release of pressure built up when the plates spread apart or move
past each or under each other. In slightly more complicated ways,
magma is generated at most plate boundaries, and this magma rises to
the surface to form volcanoes. In recent weeks, earthquakes have
exponentially increased in magnitude worldwide, worrying some
researchers as they provide the fuse that ignites volcanoes.
The
movement of magma within a volcano causes earthquakes, usually small
ones. Earthquakes are also caused by adjustments to the flanks of
volcanoes and the plates under volcanoes.
For
decades, a source of powerful earthquakes and volcanic activity on
the Pacific Rim was shrouded in secrecy, as the Soviet government
kept outsiders away from what is now referred to as the Russian Far
East.
In
the last 20 years research has shown that the Kamchatka Peninsula and
Kuril Islands are a seismic and volcanic hotbed, with a potential to
trigger tsunamis that pose a risk to the rest of the Pacific Basin.
A
magnitude 9 earthquake in that region in 1952 caused significant
damage elsewhere on the Pacific Rim, and even less-powerful quakes
have had effects throughout the Pacific Basin.
“There’s
not a large population in the Russian Far East, but it’s obviously
important to the people who live there. Thousands of people were
killed in tsunamis because of the earthquake in 1952.
Earthquakes
greater than magnitude 8 struck the central Kurils in 2006 and 2007,
and both produced large local tsunamis, up to about 50 feet. Though
the tsunamis that 
crossed
the Pacific were much smaller, the one from the 2006 quake did more
than $10 million in damage at Crescent City, Calif.
In
2009, Sarychev Peak in the Kurils erupted spectacularly, disrupting
air traffic over the North Pacific.
Clearly, determining the
frequency of such events is important to many people over a broad
area, Bourgeois said.
“Let’s
say you decide to build a nuclear power plant in Crescent City. You
have to consider local events, but you also have to consider
non-local events, worst-case scenarios, which includes tsunamis
coming across the Pacific,” she said.
But
that is only possible by understanding the nature of the hazards, and
the historic record for earthquakes, tsunamis and volcanic eruptions
in Kamchatka and the Kurils is relatively short.
In
addition, because the region was closed off from much of the world
for decades, much of the information has started becoming available
only recently.
Much
has been learned in the last 10 years in the examination of tsunami
deposits and other evidence of prehistoric events, but more field
work in the Kamchatka-Kurils subduction zone is required to get a
clearer picture.
For
hazard analysis, you should just assume that a subduction zone can
produce a magnitude 9 earthquake.
So
it is important to “pay attention to the prehistoric record” to
know where, and how often, such major events occur.
It
has been noted that in the last 25 years research in the Cascadia
subduction zone off the coast of Washington, Oregon, northern
California and British Columbia has demonstrated that the historic
record does not provide a good characterization of the hazard.
It
was once assumed the risks in the Northwest were small, but the
research has shown that, before there were any written records,
Cascadia produced at least one magnitude 9 earthquake and a tsunami
that struck Japan.
Alaska’s
Aleutian Islands and the Komandorsky Islands, an extension of the
Aleutians controlled by Russia, are another source of seismic and
volcanic activity that need to be evaluated for their potential risk
beyond what is known from the historical record.
“The
Aleutians are under-studied,” Bourgeois said. “The work in the
Russian Far East is kind of a template for the Aleutians.”
Ideally,
a dedicated boat could ferry researchers to a number of islands in
the Aleutian chain, similar to how Bourgeois and other scientists
from the United States, Japan and Russia have carried out a detailed
research project in the Kuril Islands in the last decade.
Over
the last couple of years researchers have gradually shifted from the
decades old belief that asteroids killed the dinosaurs. As a former
college history professor, I can confirm that almost all text books
claim dinosaurs were killed 65-million-years ago by an asteroid
slamming into the earth.
Today,
research suggests that tens of thousands of years of lava flow from
the Deccan Traps, a volcanic region near Mumbai may have spewed
poisonous levels of sulphur and carbon dioxide into the atmosphere
and caused the mass extinction through the resulting global warming
and ocean acidification.
The
findings are the latest volley in an ongoing debate over whether an
asteroid or volcanism killed off the dinosaurs in the mass die-off
known as the K-T extinction, the ‘Live Science’ reported.
Proponents
of the old hypothesis argue that a giant meteorite impact at
Chicxulub, Mexico, around 65 million years ago released toxic amounts
of dust and gas into the atmosphere, blocking out the Sun to cause
widespread cooling, choking the dinosaurs and poisoning sea life.
The
further point out that the meteorite impact may also have set off
volcanic activity, earthquakes and tsunamis.
In
2009, oil companies drilling off the Eastern coast of India uncovered
eons-old lava-filled sediments buried nearly 3.3 kilometers below the
ocean surface. They contained
plentiful
fossils from around the boundary between the Cretaceous-Tertiary
periods, or K-T Boundary, when dinosaurs vanished.
The sediments
bore layers of lava that had travelled nearly 1,603 km from the
Deccan Traps.
The
volcanic region, today, spans an area as big as France, but was
nearly the area of Europe when it was active during the late
Cretaceous period, said Adatte Thierry, a geologist from the
University of Lausanne in France.
The
idea that volcanic eruption may have terminated life on earth for the
dinosaur, simply wakes you up when you consider the true danger an
eruption poses to civilization. It’s even more daunting when you
grasp the fact that earthquakes are essentially the fuse that sets
them off.
In
recent weeks, worldwide earthquake data indicates an increase in the
magnitude and a significant increase in the frequency (magnitude >
5.5) of earthquakes.
Current
graphs clearly show an alarming worldwide trend of increasing
earthquake strength and frequency. These results are in agreement
with the USGS statistics page, which shows an increase in the
frequency of stronger earthquakes (M > 5.0).
These
trends also show that the depth of earthquakes has diminished, they
occur closer to the Earth’s surface. Shallow earthquakes occur
along fault lines and are due to the accumulation of stress.
Earthquake waves can also propagate far enough to trigger other
earthquakes; this may explain the noted increase in earthquakes.
Certain
scientists have stated that the increased frequency of earthquakes is
due to the increased number of detection instruments installed
worldwide. This would cause more sensitive earthquakes to be
measured. However, these graphs show an increase in stronger
earthquakes; it is also important to note that the earthquake Richter
scale is base-10 logarithmic.
The
fact that the world’s population has increased doesn’t help, more
people are affected by these events.
There
is increased media availability and attention. However, due to recent
events, it is now easy to convince even the average person, that
there are more and more strong earthquakes occurring worldwide:
A
Yellowstone National Park earthquake in Wyoming was felt in sections
of Montana and Idaho. The Wyoming earthquake, which occurred on
December 15, 2012 was centered in the northwest corner of the state.
Though there were no reports of damage we must remember Yellowstone
Caldera is located in the northwest corner of Wyoming.
Here’s
the history lesson. Yellowstone lies over a hotspot of molten mantle
rock that occasionally rises towards the surface.
Over
the past 18 million years, Yellowstone has generated a succession of
violent eruptions; some of them have been classified as
supereruptions.
Volcanic
eruptions can empty their storage of magma so quickly that they can
cause the superimposing land to collapse into a magma chamber,
forming a geographic depression called a caldera. I’m talking about
a lake the size of the state of Texas and perhaps that estimation is
significantly under estimated.
Yellowstone
Caldera is called a Supervolcano because it’s able to produce
extraordinarily huge volcanic explosions.
Because
of the volcanic and tectonic nature of the region, the Caldera
experiences somewhere between 1000 and 2000 earthquakes a year.
The
last supereruption on the Yellowstone volcano occurred approximately
640,000 years ago. The event ejected more than 240 cubic miles of
volcanic ash into the sky and across the plain.
On
Saturday December 15, 2012, shortly after 12:25 p.m. local time, a
light earthquake stuck Yellowstone National Park in Wyoming. The
quake, however, had nominal depth. Officials say the quake was only
six miles below the earth’s surface. As a result, the quake could
be felt across the region.
USGS
indicates that the quake erupted twenty-five miles south of Cooke
City-Silver Gate, Montana. The quake was also forty-four miles
southeast of Gardiner, Montana. Officials tell news the quake was
forty-seven miles west of Cody, Wyoming and roughly two hundred
eighty miles north of Salt Lake City, Utah.
As
I mentioned earlier, quakes visit the area frequently, without
causing major alarm. Nevertheless, the Yellowstone Supervolcano is
amongst the largest in recorded world history, thus it poses a threat
of considerable proportions. Most researchers claim that if it
erupted today, it would come close the obliterating the entire land
area known as the United States. In addition, it would likely have an
enormous consequences on world weather, agriculture and quality of
life.
There
are an estimated 1,500 active volcanoes around the world, 50 to 60
erupt every year, spewing steam, ash, gas and lava. These
reflectively, mild outburst don’t come close to the dangers
Yellowstone present. The fact is, if it were ever to erupt, it would
only take moments to end the life of everyone in close proximity. If
you like in the USA, the idea of escaping its reach is borderline
fantasy. In other words, it would be practically impossible. One can
only hope that it doesn’t blow in our lifetime; but it is certain
to erupt in someone’s lifetime.
All
it takes is a few well placed earthquakes for it to blow.
Technology
certainly has its hands full.
Costa
Rica saw most seismic activity in past 62 years during 2012
31
December, 2012
December
31st, 2012 (InsideCostaRica.com) According to the Costa
Rican Volcanology and Seismology Observatory (OVSICORI), after the
magnitude 7.6 earthquake which occurred on September 5th,
2012, the country registered the highest level of earthquake activity
it has seen in 62 years.
The
strongest earthquakes in Costa Rican history occurred in 1950 in
Nicoya, with a 7.8 magnitude quake, followed by the 2012 earthquake
that occurred in the same area, of a 7.6 magnitude.
After
the September 5th earthquake, OVSICORI reported 75
earthquakes that were felt by residents during the 4 months after the
main event.
2010
saw a total of 6,245 earthquakes, in 2011 there were 5,483, and in
2012 the total was 11,049.
Over
3,000 Noticeable Quakes Hit Japan In 2012
31
December, 2012
Japan
had experienced a little over 3,000 noticeable earthquakes in 2012,
nearly 60 percent of them aftershocks from last year's massive tremor
that devastated the country's northeast, Japanese media reported on
Monday.
Quoting
the Japan Meteorological Agency, the NHK broadcaster reported that a
total of 3,134 quakes had been felt across Japan until Sunday
(December 30) which is about 1,000 more than the annual average from
2001 to 2010.
An
analysis of seismic waves indicates that there were more than 10,000
noticeable quakes in 2011. While the number of quakes decreased from
that of last year, seismologists continue to monitor frequent seismic
activity.
They
urged people to be on the alert for possible strong quakes with a
magnitude of at least 7 or those triggering tsunami.
The
March 11, 2011 quake and the tsunami it triggered had left more than
15,000 people dead or missing besides wreaking havoc in Japan's
northeast, including the meltdown at the Fukushima Daiichi nuclear
power plant that leaked radiation forcing the evacuation of more than
160,000 residents.
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