Many people think that an earthquake is just a simple rattle in the earth the destruction from this type of natural disaster can be devastating. Seismologists have been studying earthquakes for many years to help us to figure out where and when they are going to happen. An earthquake is the trembling of the earth’s surface caused by rapid movement of the earth’s rocky outer layer. They occur when energy stored in the earth, usually in the form of strain in rocks, suddenly releases. This energy is transmitted to the surface of the earth by earthquake waves (known as primary and secondary waves).
The destruction an earthquake causes mainly depends on its magnitude and duration. However, a buildings structural design as well as the materials used in the construction process also effects the amount of damage done when an earthquake hits. Some earthquakes are small and we don’t even notice them, while others can be felt over thousands of kilometers.

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Engr.Aftab