Introduction
One of the most frightening and
destructive phenomena of nature
is a severe earthquake and its
terrible aftereffects.
An earthquake is a sudden movement
of the Earth, caused by the abrupt release
of strain that has
accumulated over a long time. For hundreds
of millions of years, the forces of plate
tectonics have shaped the Earth as the
huge plates that form the Earth's surface
slowly move over, under, and past each other.
Sometimes the movement is gradual.
At other times, the plates are locked
together, unable to release the accumulating
energy. When the accumulated energy grows strong
enough, the plates break free.
If the earthquake occurs in
a populated area, it may cause many
deaths and injuries and
extensive property damage.
Full size image - 155k
Today we are challenging the
assumption that earthquakes must present
an uncontrollable and unpredictable
hazard to life and property.
Scientists have begun to estimate
the locations and likelihoods of future
damaging earthquakes.
Sites of greatest hazard are being
identified, and definite progress
is being made in designing structures
that will withstand the effects of earthquakes.
Many buildings in Charleston, South Carolina, were damaged or destroyed by the large earthquake that occured August 31, 1886. - 87k