Quake
Moved Japan Coast
8 feet; Shifted Earth's Axis
March 12,
2011
..
Quake moved
Japan coast 8 feet;
shifted Earth's axis
By Kevin Voigt,
CNN
March 12,
2011
(CNN) -- The
powerful earthquake that unleashed a devastating
tsunami Friday appears to have moved the main island
of Japan by 8 feet
(2.4 meters) and shifted the Earth on its axis.
"At this point, we
know that one GPS station moved
(8 feet), and we have seen a map from GSI
(Geospatial Information Authority)
in Japan showing the pattern of shift over a large
area is consistent with
about that much shift of the land mass," said
Kenneth Hudnut, a geophysicist
with the U.S. Geological Survey (USGS).
Reports from the
National Institute of Geophysics and
Volcanology in Italy estimated the 8.9-magnitude
quake shifted the planet
on its axis by nearly 4 inches (10 centimeters).
The temblor, which
struck Friday afternoon near the
east coast of Japan, killed hundreds of people,
caused the formation of
30-foot walls of water that swept across rice
fields, engulfed entire towns,
dragged houses onto highways, and tossed cars and
boats like toys. Some
waves reached six miles (10 kilometers) inland in
Miyagi Prefecture on
Japan's east coast.
The quake was the
most powerful to hit the island nation
in recorded history and the tsunami it unleashed
traveled across the Pacific
Ocean, triggering tsunami warnings and alerts for 50
countries and territories
as far away as the western coasts of Canada, the
U.S. and Chile. The quake
triggered more than 160 aftershocks in the first 24
hours -- 141 measuring
5.0-magnitude or more.
The quake occurred
as the Earth's crust ruptured along
an area about 250 miles (400 kilometers) long by 100
miles (160 kilometers)
wide, as tectonic plates slipped more than 18
meters, said Shengzao Chen,
a USGS geophysicist.
Japan is located
along the Pacific "ring of fire,"
an area of high seismic and volcanic activity
stretching from New Zealand
in the South Pacific up through Japan, across to
Alaska and down the west
coasts of North and South America. The quake was
"hundreds of times larger"
than the 2010 quake that ravaged Haiti, said Jim
Gaherty of the LaMont-Doherty
Earth Observatory at Columbia University.
The Japanese quake
was of similar strength to the 2004
earthquake in Indonesia that triggered a tsunami
that killed over 200,000
people in more than a dozen countries around the
Indian Ocean. "The tsunami
that
it sent out was roughly comparable in terms of
size," Gaherty said. "[The
2004 tsunami] happened to hit some regions that were
not very prepared
for tsunamis ... we didn't really have a very
sophisticated tsunami warning
system in the Indian Ocean basin at the time so the
damage was significantly
worse."
The Japanese quake
comes just weeks after a 6.3-magnitude
earthquake struck Christchurch on February 22,
toppling historic buildings
and killing more than 150 people. The timeframe of
the two quakes have
raised questions whether the two incidents are
related, but experts say
the distance between the two incidents makes that
unlikely.
"I would think the
connection is very slim," said Prof.
Stephan Grilli, ocean engineering professor at the
University of Rhode
Island.
SOURCE: CNN
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