EARTHQUAKE & TSUNAMI

Earthquake
The surface of the Earth is like a massive jigsaw puzzle made up of huge rocky pieces called tectonic plates. The pieces of this puzzle are constantly moving about very slowly, but with immerse force. If they slide past or crash into each other the Earth shakes and quakes.


Most earthquakes occur at depths of less than 80 km (50 miles) below the Earth’s surface.
According to the United States Geological Survey, there are more than 3 million earthquakes every year. That’s about 8,000 a day, or one every 11 seconds! Most of these are too weak to be noticed.



Tsunami
If an earthquake happens under water it can cause a tsunami  - a serious of powerful and destructive ocean waves. An earthquake in the Indian Ocean on 24 Dec. 2004 triggered a series of tsunamis killing more than 225,000 people in 11 countries !  Recently in Japan, a series of earthquakes accompained by tsunamis has killed thousands of people and destroyed huge amount of  property !