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Natural phenomena like cyclone and thunderstorm can cause large scale destruction to human life and property. But, one can predict this phenomena to some extent. The weather department can warn about a thunderstorm developing in some areas.
 
The weather department cannot predict earthquakes, so there is no time to protect life and property. It can cause damage to life and property.
  
Earthquake:
A sudden shake or trembling of the earth which lasts for a very short time is referred to as an earthquake. A sudden shaking of the earth can cause enormous damage to buildings, dams, etc. They may also cause floods, landslides, tsunami's and loss of life.
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Damaged building due to earthquake
  
Causes of earthquakes:
  • Earthquakes are caused by a sudden disturbance deep inside the earth's crust.
  • The outer layer of the earth is fragmented. Each fragment is called a plate.
  • Earth's plates are in continual motion, so there is a chance of collision between the plates that cause disturbance in the earth's crust.
  • This disturbance in the earth's crust shows up as an earthquake on the earth's surface.
  • The other cause of earthquakes are volcanic eruptions, meteor hits and nuclear explosions.
Even though we know the cause of earthquakes, it is not yet possible to predict when and where the next earthquake might occur.
 
Seismic or fault zones:
The movement of plates causes earthquakes; the plates are weak in their boundaries, so they are referred to as weak zones where earthquakes are more likely to occur. The weak zones are also known as seismic or fault zones.