2. What happens during an earthquake?
• Tectonic plates fold either under or over one another causing the ground
to crack and crumble. They also could start a tsunami.
• An earthquake is the sudden, rapid shaking of the earth, caused by the
breaking and shifting of subterranean rock as it releases strain that has
accumulated over a long time.
3. How it is hazardous to humans
• It could cause lots of damage to their homes, personal items,
pets and their entire cities.
• Serious injury or even dead.
4. In What Areas do Earthquakes Occur
Most Often?
• Earthquakes occur most where there are lots
of plates and plate movement which is mostly
near the mountains.
5. How is an earthquake measured?
• A Richter Scale, (left) developed by Charles F. Richter in 1934, used a formula
based on amplitude showing how powerful the waves are that the shaking
produces.
• Seismometers (right) are instruments that measure motions of the ground.
Records of seismic waves.
6. Devastating Earthquakes 1 of 2
• The 2004 Indian Ocean Earthquake
• Sunday, December 26, 2004.
• It was an undersea earthquake, killing over 230,000 people in fourteen
countries.
• With a magnitude of Mw 9.1–9.3, it is the third largest earthquake ever
recorded on a seismograph.
• The earthquake had the longest duration of faulting ever observed,
between 8.3 and 10 minutes.
7. Devastating Earthquakes 2 of 2
• The 2010 Chile earthquake
• Saturday, February 27, 2010.
• Occurred off the coast of central Chile.
• Magnitude of 8.8 on the moment magnitude scale.
• Intense shaking lasting for about three minutes.
• It ranks as the sixth largest earthquake ever to be recorded
by a seismongraph It was felt strongly in six Chilean regions
that made up about 80 percent of the country's population.
8. Earthquake Protection
• "Drop, Cover, and Hold On" Drop to the floor, take cover under a sturdy desk or
table, and hold on to it firmly. Be prepared to move with it until the shaking stops.
• Build an emergency kit and make a family communications plan.
• Fasten shelves securely to walls. Place large or heavy objects on lower shelves.
Store breakable items such as bottled foods, glass, and china in low, closed
cabinets with latches