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Predictability of Earthquakes
►Although some scientists claim ability to
predict earthquakes, the methods are
►Mechanical observation systems make it
possible to issue warnings to nearby
populations immediately after detection of
Measuring Magnitude of
The magnitude of most earthquakes is
measured on the Richter scale, invented
by Charles F. Richter in 1934.
The Richter magnitude is calculated from
the amplitude of the largest seismic wave
recorded for the earthquake, no matter
what type of wave was the strongest.
What to do during
Stay as safe as possible during an
Be aware that some earthquakes are
actually foreshocks and a larger
earthquake might occur.
Minimize your movements to a few steps
to a nearby safe place and if you are
indoors, stay there until the shaking has
stopped and you are sure exiting is safe.
If indoors :
DROP to the ground; take COVER by
getting under a sturdy table or other piece
of furniture; and HOLD ON until the
If there isn’t a table or desk near you,
cover your face and head with your arms
and crouch in an inside corner of the
Stay away from glass, windows, outside doors
and walls, and anything that could fall, such as
lighting fixtures or furniture.
Stay in bed if you are there when the earthquake
strikes. Hold on and protect your head with a
pillow, unless you are under a heavy light fixture
that could fall. In that case, move to the nearest
Use a doorway for shelter only if it is in
close proximity to you and if you know it is
a strongly supported, load bearing
Stay inside until the shaking stops and it is
safe to go outside. Research has shown
that most injuries occur when people
inside buildings attempt to move to a
different location inside the building or try
• Be aware that the electricity may go out or
the sprinkler systems or fire alarms may
Move away from buildings, streetlights and
Once in the open, stay there until the
If in a moving vehicle, stop as quickly as
safety permits and stay in the vehicle.
Avoid stopping near or under buildings,
trees, overpasses, and utility wires.
Proceed cautiously once the earthquake
has stopped. Avoid roads, bridges, or
ramps that might have been damaged by
If trapped under debris, do not light a match, do
not move about or kick up dust, cover your
mouth with a handkerchief or clothing.
Tap on a pipe or wall so rescuers can locate you.
Use a whistle if one is available. Shout only as a
last resort. Shouting can cause you to inhale
dangerous amounts of dust.
Facts of Earthquakes
The largest recorded earthquake in the
United States was a magnitude 9.2 that
struck Prince William Sound, Alaska on
Good Friday, March 28, 1964 UTC.
The largest recorded earthquake in the
world was a magnitude 9.5 (Mw) in Chile
on May 22, 1960.
• The first “pendulum seism scope” to
measure the shaking of the ground during
an earthquake was developed in 1751,
and it wasn’t until 1855 that faults were
recognized as the source of earthquakes.
►It is estimated that there are 500,000
detectable earthquakes in the world each
year. 100,000 of those can be felt, and
100 of them cause damage.
►It is thought that more damage was done
by the resulting fire after the 1906 San
Francisco earthquake than by the
From 1975-1995 there were only four
states that did not have any earthquakes.
They were: Florida, Iowa, North Dakota,
Most earthquakes occur at depths of less
than 80 km (50 miles) from the Earth’s
Florida and North Dakota have the
smallest number of earthquakes in the
It was recognized as early as 350 BC by
the Greek scientist Aristotle that soft
ground shakes more than hard rock in an
In 1663 the European settlers experienced
their first earthquake in America.
Earthquakes are one natural calamity
which isn't dependent on the weather.
Therefore, earthquakes can occur whether
its the cold, hot or rainy season.
Advantages of Earthquakes
Earthquake pushes the land further up,
thus helping vegetation flourish. So it is
part of shaping the earth.
It also loosens and churns the soil, allowing
nutrients and minerals to be deposited evenly,
creating a very fertile soil.