An earthquake is a shaking of the ground caused by the sudden breaking and movement of large sections (tectonic plates) of the earth's rocky outermost crust.

Earthquakes happen when the moving tectonic plates that make up the surface of the Earth move apart or bump into each other, or slide under each other.

Within areas of the crust are fractures, known as faults, along which two crustal blocks have slipped or moved against each other.

The ground shakes during an earthquake because the plates underneath are continuously moving at a slow pace, but as they are moving they are rubbing against each other and eventually on plate will slip under another and this sudden 'shift' causes an earth quake.

Aftershocks are lesser earthquakes that occur after a major one, along the same fault.

Earthquakes and tsunamis are alike because an earthquake causes a tsunami wave, as the earthquake creates a force pushing the water to shore.

Scientists normally use something called the Richter scale to measure earthquakes. They measure in magnitude. 1 on the Richter scale would be small vibrations through the earthquake zone where as 10 would be total destruction.

Earthquake prediction is currently not possible. Seismologists will attempt to quantify the risk posed by a particular fault zone rather than state exactly when an earthquake will occur.

Well, earthquakes happen naturally when two tectonic plates grind into each other. But, when it get's too strong, this is when we can feel it. Most people take earthquake in a negative way, but earthquake is one of the proofs that tells us that earth is still active. If there were no earthquakes, we wouldn't have mountains, rivers, and all the other beautiful views. In fact, the earth would be cold and dry as the moon. Even though, earthquake destroys a lot of things and kills a lot of people, it's just the way things are. It tells us that earth is still a planet that we can live in.

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