Transcript Earthquake structure

How does the
movement of a plate do
this?
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How do earthquakes happen?
1. Explain how an earthquake occurs (helpful
words might be pressure, tension, breaking crust sudden, release
etc)
2. Draw a diagram to that show the following
features :
Focus
Epicenter
Seismic Waves
( Wider World p270 has diagram and explanation from Kobe which is
helpful)
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How to measure the magnitude
(strength) of an earthquake
•
http://www.schoolportal.co.uk/GroupDownlo
adFile.asp?file=21416
• Richter Scale
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Liquefaction
• Liquefaction happens when an earthquake
shakes wet soil. The water rises to the
surface and turns solid soil into liquid mud.
Buildings then sink into this mud.
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• It was an undignified thing to
happen to a block of flats. Japan
is an earthquake-aware country,
and when apartment complexes
were built in the Kawagishi-cho
area in the city of Niigata, they
were sturdy reinforced concrete.
But after a magnitude 7.5 shock
on 16 June 1964, it was not the
structures that gave way but the
ground beneath them. Hundreds
of buildings tilted like ships
listing in heavy seas, victims of
soil liquefaction. When the time
came for repairs, some of the
buildings were simply winched
back upright.
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Tsunami
• A Tsunami is a large wave of seawater that can
travel for thousands of miles and is triggered by
an underwater earthquake.
• http://news.bbc.co.uk/1/hi/in_depth/world/2004/a
sia_quake_disaster/default.stm
• http://www.bbc.co.uk/schools/gcsebitesize/geogr
aphy/platetectonics/quake_video.shtml
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New Tsunami, Yesterday
• 6.0 magnitude earthquake hits Indonesia
• (AFP) – 2 hours ago
• JAKARTA — A strong 6.0-magnitude earthquake hit Indonesia's
Java island on Tuesday, seismologists said, but no tsunami warning
was issued.
• The quake struck 147 kilometres (91 miles) southeast of Sukabumi
at a depth of 13 kilometres, at 18.59 pm (09:59 GMT), the
Meteorological and Geophysics Agency said.
• "There are no reports on damage or victims so far. We felt the quake
only briefly and there was no panic here," Cianjur police chief
Wibowo said.
• The town of Cianjur is close to Sukabumi.
• "The quake occured on the sea. It's the tsunami we were afraid of.
But there is no tsunami warning," he said.
• Indonesia sits on the Pacific "Ring of Fire", where the meeting of
continental plates causes high volcanic and seismic activity.
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