Page 316 - (DK) I Can’t Believe It! 2

314
Earthquakes
TRUE or
FALSE?

are very rare

Untrue—every year there are several million

earthquakes. Most are just gentle wobbles,
while a handful are earth-shattering, causing

widespread devastation.
The rocky plates of Earth’s crust move
Richter scale constantly, and when they meet or slide
6–6.9 = strong, past each other, earthquakes result.
severe, sudden These are usually slight tremors,
movement, on unless the rocks on either side of a
average 120 a year plate boundary lock together, creating
much deeper vibrations. In 1934,
American scientist Charles Richter
designed the Richter scale—a way
to measure earthquakes using
instruments called seismographs.

WAVES OF DESTRUCTION

A huge earthquake on the seabed can
trigger a series of catastrophic waves,
called tsunamis. Traveling at speeds up
to 586 mph (943 km/h), they cause
mass devastation upon reaching land,
bringing down buildings and destroying life.

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