1. © 2014 wheresjenny.com An earthquake also known as a quake, tremor or temblor It is the result of a sudden release of energy in the Earth’s crust that creates seismic waves. What Are Seismic Waves? Seismic waves are the waves of energy caused by the sudden breaking of rock within the earth or an explosion. They are the energy that travels through the earth and is recorded on seismographs. The seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time. Earthquake

2. © 2014 wheresjenny.com Earthquakes are usually caused when rock underground suddenly breaks along a fault. This sudden release of energy causes the seismic waves that make the ground shake. When two blocks of rock or two plates are rubbing against each other, they stick a little. They don't just slide smoothly; the rocks catch on each other. The rocks are still pushing against each other, but not moving. After a while, the rocks break because of all the pressure that's built up. When the rocks break, the earthquake occurs. Why do earthquakes happen?

3. © 2014 wheresjenny.com Earthquakes are caused by disturbances in the interior of the earth and other causes. Tectonic movements: The disturbances inside the earth are called tectonic movements. These forces bring about changes on the earth surface and physical features like mountains, plateaus and rift valleys are formed Most disastrous Earthquakes are caused by Tectonic forces Causes of earthquake

4. © 2014 wheresjenny.com Volcanic Eruptions: The volcanic eruptions are often very violent and cause vibrations in the earth crust Sometimes the vent of a volcano is blocked temporarily and explosive eruption takes place suddenly causing tremors in the earth crust Volcanic eruptions

5. © 2014 wheresjenny.com Other Reasons: The roofs of underground caves sometimes give way and release great force to cause minor tremors in the earth crust. Nuclear explosions also release massive energy to cause tremors in the earth crust. Other reasons for earthquake

6. © 2014 wheresjenny.com Earthquakes are less advantageous and more harmful to man Loss of Property: Severe earthquakes reduces human structures to rubble ranging from huts to palaces and single storey to multi storey buildings. Even pipelines laid under the ground and railway lines are damaged or displaced Loss of Life: Earthquake tremors of a few seconds takes the lives of thousands of people. Many people have been rendered homeless or suffered injuries in various ways. Effects of Earthquake

7. © 2014 wheresjenny.com Tsunamis: The earthquakes in the sea generate massive waves. It causes great damage to life and property of people living in coastal areas as well as to tourists Tsunami caused by an earthquake in the sea near Sumatra on 26th Dec,2004 hit south east Asian countries including India and Sri Lanka.There was heavy damage in these countries and more than 3 lakh people died Effects of Earthquake

8. © 2014 wheresjenny.com Earthquake Safety Measures Drop down; take cover under a desk or table and hold on. Stay indoors until the shaking stops and you're sure it's safe to exit. Stay away from bookcases or furniture that can fall on you. Stay away from windows. In a high-rise building, expect the fire alarms and sprinklers to go off during a quake. If you are in bed, hold on and stay there, protecting your head with a pillow. If you are outdoors, find a clear spot away from buildings, trees, and power lines. Drop to the ground. If you are in a car, slow down and drive to a clear place. Stay in the car until the shaking stops.