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Earthquake's
Earthquakes are probably the most feared disasters of all.They occur completely without warning:
they are terrifying to both humans and animals: and they cause death and destruction on an
unimaginable scale.
In 1999 massive quakes ripped through western Colombia , Turkey (twice) Taiwan and Mexico
killing over 20,000 people ,injured far more and left countless thousands homeless . In a matter of
a few seconds, the victims of an earthquake can have their lives changed forever. Earthquakes,
like volcanoes, result from the shifting and grinding together of "tectonic plates" - great floating
chunks of the earth's mantle - separated by fault lines. The famous California San Andreas Fault
can be clearly seen from the air running from the Mojave Desert in the south to just north of San
Francisco.
But hundreds of other fault lines criss-cross the earth, many far from major plate boundaries.
Sometimes plates will rub together, sometimes they will dive under one another (known as
"subduction"), and in each case can suddenly release enormous amounts of energy. As the
"shock waves" ripple out from the subterranean movement, the earth becomes like the surfaceof
a pond when a stone is thrown into it. The ripples move outwards, often at tremendous speed,
and everything in their paths is shaken like a child's toy.
Scientists are at a total loss to predict the moment and the severity of temblors,and little progress
in prediction is contemplated. Thus preparing for an earthquake is not something one does after
hearing a warning on the radio. It requires constant vigilance. There is never a question of
whether an earthquake will strike, virtually anywhere on earth. The only questions are when and
with what ferocity.
In the Caribbean, earthquakes are actually quite common.Hundreds occur every day, although
almost none is detectable except by sensitive instruments. The North American Plate is
constantly being ground beneath the Caribbean Plate - and along that most of the Caribbean
islands have emerged through volcanic activity.
The most famous Caribbean quake was at the swash-buckling pirate haven of Port Royal in
Jamaica at the end of the 17th century. Thousands died as the entire port town was virtually
dropped into the sea. Big earthquakes have also been recorded in the Eastern Caribbean and in
the southern Windward Islands, some as recently as three years ago. The watchword here is be
prepared.
When the quake hits . . .
· Do not leave your house. More people die from falling debris outside than from any other effect
of an earthquake. Immediately get into a doorway or passageway, which, if the building is
properly constructed, will be secured by a "header," a heavy length of wood that supports the
opening from above. These are the strongest parts of any house.
· Cover your face with your hands. A rocking, twisting building will often "blow out" windows,
sending shards of flying glass.
· If you cannot reach a doorway or passageway, duck under a sturdy table or into a closet, which
will protect you from shifting furniture and flying debris.
· If you are outside, do not try to enter any building. Get as far into the open as you can, well clear
of any falling material. Watch for fissures opening in the earth (these deformations are rare,
regardless of what Hollywood filmmakers tell us, but they are possible). If you are in your car,
stop in an open spot and wait it out. A car is the safest place to be in a quake.
· After the initial shock, be prepared for aftershocks, for they are inevitable. Sometimes, as in the
Big Bear Lake/Landers (California) quakes of 1992, an aftershock can even be a second, larger
quake, triggered by the first. Aftershocks, while usually mild, can topple buildings and other
structures weakened by the main quake - so beware.
After the Big One . . .
· Immediately check for broken gas, sewer, water and electrical lines. Shut off utilities at the
meters should damage be found.
· Check for structural damage. Telltale signs are broken or wrinkled plaster walls, ill-fitting doors,
and foundation cracks. Take photos for insurance purposes.
· Stay away from fallen power lines and stay off the roads.
Earthquake tips . . .
· Certain items of furniture, especially bookshelves and other freestanding units,should be
securely attached to the wall with screws. Much damage and injury can result from things being
"thrown" off shelves and from toppling furniture. Make sure that cupboard and closet latches are
in good order and hold doors closed tightly.
· Secure computers and other electronic equipment with Velcro strips. These are available in
hardware stores. One side glues to the table or desk, and the other to the piece of equipment to
prevent shifting. In a serious quake, whatever is not on the floor before it hits will be on the floor
when it's over.
· Strap water heaters in place with metal or canvas belts. These are also available at hardware
shops, complete with instructions.
· Always have a portable battery-powered radio on hand and fresh replacement batteries.
· Keep a good supply of fresh drinking water stored at all times. Earthquakes can snap sewer
lines like twigs, contaminating water supplies.
· Have enough canned food and drink on hand to last at least two days for everyone in your
household, including pets.
· Keep two or three gallon plastic bottles of frozen water in the freezer to serve as a makeshift
refrigerator during power outages.
· If your house or office is built from stone or concrete or brick - anything but wood - predetermine the safest spot to go to when a quake hits. Earthquakes do not kill; falling buildings do.
· Your cats, and sometimes your dogs, will probably be more terrified than you in a quake. Cats
can be gone for days, and dogs can be spooked for a long time afterwards. Don't worry, they too
will recover.
· Remember, earthquakes - by their suddeness, noise and chaos - can be psychologically
devastating. It is critical that victims stay calm and composed and do not panic into dangerous
behaviour. During a quake a single second can seem like an excruciating hour, and it might take
months to get mentally readjusted after a bad shaker. Bear in mind that things can be replaced,
humans cannot.
Source: http://www.antor.org/earthquakes.html