Earth's Crust

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Earth's Crust
Natural Disasters to Remember.
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Peru Mudslide
Mount Huascaran in 1970 let go of a chunk of ice
measuring 900m wide and 1500m long during an
earthquake. The ice crashed down the mountain
gathering rock, dirt and other debris. It started
to melt and the water mixed with the dirt
creating a mudslide that buried the town of
Yungay killing 20,000. The slide reached speeds
of 210 km/hr. In all nearly 70,000 people lost
their lives.
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Krakatoa
Krakatoa is a volcanic island in the Sunda Strait
between Java and Sumatra in Indonesia. In 1883 an
eruption ejected more than 25 cubic kilometres of
rock, ash, and pumice 1, and generated the
loudest sound ever historically reported.The
explosion was distinctly heard as far away as
Australia (approx. 3100 km, and the island of
Rodrigues near Mauritius (approx. 4800km). Shock
waves reverberated around the world seven times
and were felt for five days. 165 villages and
towns were destroyed and 132 seriously damaged,
at least 36,417 (official toll) people died, and
many thousands were injured by the eruption,
mostly in the tsunamis which followed the
explosion. Tide gauges also recorded the sea
wave's passage far from Krakatau. The wave
"reached Aden in 12 hours, a distance of 3800
nautical miles, usually traversed by a good
steamer in 12 days". The dust that went into the
atmosphere created spectacular suns that appeared
green, and blue , spectacular sunsets occurred
for years as far away as New York. It changed the
climate of the planet for the next year lowering
the temperature by 1.2 degrees CelsiusNew
eruptions at the volcano since 1927 have built a
new island, called Anak Krakatau (child of
Krakatoa).
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Mt.St.Helens
An active stratovolcano, is located in southwest
Washington State, USA approximately a 3 hour
drive from Seattle, WA and a 2 and 1/2 hour drive
from Portland. It was 9,677 feet before the
eruption and 8,363 feet after. The largest
landslide in recorded history swept down the
mountain at speeds of 70 to 150 miles per hour
and buried the North Fork of the Toutle River
under an average of 150 feet of debris.  Some
areas are covered by as much as 600 feet.  The
lateral blast swept out of the north side of MSH
at 300 miles per hour.  Temperatures reached as
high as 660 degrees F .The snow melted and
created mudflows that destroyed 27 bridges, 200
homes, 185 miles of roadway, and 15 miles of
railway .57 people were killed as a result of
the eruption , 7,000 big game animals, 12 million
Chinook and Coho salmon, and millions of birds
and small mammals are believed to have died in
the eruption.
May 18th, 1980
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San Francisco Earthquake (1908)
The California earthquake of April 18, 1906 ranks
as one of the most significant earthquakes of all
time. The quake ruptured the northernmost 477
kilometers of the San Andreas fault. The
earthquake and resulting fire would be remembered
as one of the worst natural disasters in the
history of the United States. About 3000 deaths
occurred. Between 225,000 and 300,000 people were
left homeless out of a population of about
400,000. As damaging as the earthquake and its
aftershocks were, the fires that burned out of
control afterward were much more destructive.
About 90 of the total destruction.,some
initially fueled by natural gas mains broken by
the quake. First recording of a quake with motion
pictures, lots of scientific evidence gathered
for the first time. Seismology emerging as a
field.
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2004 Tsunami
The 2004 Indian Ocean earthquake, known by the
scientific community as the Sumatra-Andaman
earthquake, was an undersea earthquake that
occurred at 005853 UTC (075853 local time) on
December 26, 2004. The earthquake triggered a
series of lethal tsunamis that spread throughout
the Indian Ocean, killing large numbers of
people. The magnitude of the earthquake was
originally recorded as 9.0 but has been upgraded
to between 9.1 and 9.3 Recent analysis indicates
the number of casualties were 186,983 dead and
42,883 missing, for a total of 229,866 affected
This earthquake was also reported to be the
longest duration of faulting ever observed,
lasting between 500 and 600 seconds, and it was
large enough that it caused the entire planet to
vibrate at least half an inch, or over a
centimetre
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Pompeii
On August 24, 79 Mount Vesuvius literally blew
its top, spewing tons of molten ash, pumice and
sulfuric gas miles into the atmosphere. A
"firestorm" of poisonous vapors and molten debris
engulfed the surrounding area suffocating the
inhabitants of the neighboring Roman resort
cities of Pompeii, Herculaneum and Stabiae. The
cities remained buried and undiscovered for
almost 1700 years until excavation began in 1748.
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Chile
1960 May 22 Magnitude 9.5 The Largest
Earthquake in the World A piece of the
Pacific seafloor (the Nazca Plate) about the size
of California slid fifty feet beneath the
continent of South America. Like a spring, the
lower slopes of the South American continent
offshore snapped upwards as much as twenty feet
while land along the Chile coast dropped about
ten feet. The main tsunami ran through the
Pacific Ocean and devastated Hilo, Hawaii, 10,000
kilometers from the epicenter, as well as coastal
regions of Japan. The total number of fatalities
from the earthquake and tsunami was estimated to
6,000 .
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Paricutin (The Birth of a Volcanoe)
On February 20, 1943 a farmer, Dionisio Pulido,
and his wife Paula were burning shrubbery in
their cornfield when they observed the earth in
front of them swell upward and crack to form a
fissure 2-2.5 m across. They heard hissing sounds
and later described the rise of "smoke" from the
fissure, which had the repugnant smell of rotten
eggs. The "rotten egg" smell is a hallmark of H2S
gas, and the crack that opened in front of them
would, within hours, develop into a small
volcano. After roughly one year the volcano had
grown 336 meters tall. For the next eight years
the volcano would continue erupting. It reached a
final height of 424 m.
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Atlantis?
Atlantis has been one of the western world's
favorite legends. Most of the information we have
about Atlantis comes from the ancient Greek
philosopher Plato. The legendOn this huge
island was a "great and wonderful empire" where
brave, virtuous people lived in a kind of
paradise. But this peaceful existence came to an
end when the people of Atlantis began to love
power more than they loved the gods. They waged
war against the rest of the world, but were
ultimately defeated by the wise and moral
Athenians. Then, some 9,000 years before Plato's
own time, or around 9,500 B.C.E., earthquakes
sunk Atlantis into the sea. Some have argued
that Atlantis was in the Americas, or in the
Canary Islands, or in Antarctica. Others think
Atlantis was in fact the Greek island of Thera,
also known as Santorinia theory fed by recent
archaeological discoveries.
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Canary Islands (Future)
One group of scientists believes that conditions
are ideal for a tsunami-producing landslide on
the island of La Palma in the Canaries. The
western flank of the island's active volcano has
the potential to give way in a future eruption.
If it did, a huge mass of rock weighing 500,000
million tons would fall into the Atlantic Ocean.
Experts in Switzerland have simulated the
potential effects of such a collapse. Their model
shows that it could generate a wave capable of
engulfing every port on the east coast of the U.S
and Canada, which they believe may have happened
during a similar tsunami 120,000 years ago.
Volcanism in the region is largely caused by
hotspots in oceanic crust.
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Canadian Earthquakes
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Canadian Volcanoes
Canada has examples of almost every type of
volcano. Although none are erupting now, at least
3 did in the last few hundred years and numerous
others have the potential to erupt in the near
future.