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Earthquakes happen around the world all the time. Most of them are tiny, and are barely felt although seismologists have ways of tracking and measuring them. Sometimes, big ones strike though. What lies behind - or rather, beneath - earthquakes? Here is a great way to see how an earthquake happens.

• A flexible rubber band
• A stapler or other heavy object
• A carpeted floor or other rough surface

1. Place the rubber band around the stapler. (You should be able to grab the rubber band and pull the stapler)
2. Place the stapler on a rough surface, preferably a carpeted floor and gently pull the rubber band. Make sure not to pull it too fast.
3. As the tension increases, watch the stapler. Eventually, the stapler will slide in the direction you are pulling the rubber band and should stop a few inches away.
4. Keep on pulling the rubber band slowly until the stapler jumps forward again.

What is happening?

When you pull on the rubber band, you are increasing the amount of tension, or pull, on the stapler. Since the stapler is somewhat heavy and since the carpet is rough, the stapler does not move until the tension becomes to great. When this happens, the stapler will jump forward and the tension in the rubber band will decrease. This is what happens to the earth. The earth’s crust is constantly pushing on each other. Since the earth’s crust is rough and heavy, it will not move until the tension becomes to great. Just like the stapler jumped forward, the earth’s crust also jumps forward creating an earthquake.