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Earthquake topics include here are: Earthquake terminology, earthquakes classification and quake resistant buidings.
What is an earthquake? An earthquake is a sudden release of strain energy in the Earth's crust. This release causes two large pieces of the Earth's crust to slip, which creates shock waves that shake the surface of the Earth.
How do earthquakes happen? The Earth's crust is fractured into tectonic plates that move slowly over the Earth's surface. This movement causes stress on the Earth's crust. When the stress builds up, the rocks slip suddenly, releasing energy in waves that travel through the Earth's crust.
Where do earthquakes occur? Earthquakes usually occur on the edges of large sections of the Earth's crust called tectonic plates.
Aftershocks Aftershocks are earthquakes that usually occur near the mainshock. They represent minor readjustments along the portion of a fault that slipped at the time of the mainshock. The frequency of these aftershocks decreases with time.
Other facts about earthquakes: Half a million occur per year. The largest recorded earthquake was a magnitude 9.5.
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