Earthquake Facts

Earthquakes are the nature's most dangerous calamity. Earthquakes can hit any place, at any time and at any extreme level. The earthquake is caused due to movement of tectonic plates below the Earth's crust when they are pushed, pulled or jostled against each other. When the pressure of this movement becomes unbearable the rocks crack and shifts and the waves of energy produced is an earthquake.

Before electronics allowed recordings of large earthquakes, scientists built large spring-pendulum seismometers in an attempt to record the long-period motion produced by such quakes. The largest one weighed about 15 tons. There is a medium-sized one three stories high in Mexico City that is still in operation.

The largest recorded earthquake in the world was a magnitude 9.5 (Mw) in Chile on May 22, 1960. The largest recorded earthquake in the United States was a magnitude 9.2 that struck Prince William Sound, Alaska on Good Friday, March 28, 1964 UTC.

More about earthquakes.