An earthquake is the trembling of the ground. Plates inside the earth shift and hit each other causing the quake. Most earthquakes take place on the edge of a plate. The begining of the earthquake is called the focus. The shaking is called seismic waves which is the Greek word for earthquake. The tremors that follow the earthquake are called aftershocks. Foreshocks are really small tremors.
Some earthquakes are barely noticeable, others are very violent and destructive. Some people believe that the continents used to be connected, and earthquakes have broken them apart. The Atlantic is widening one inch per year because of earthquakes.
Two scales are used to determine how bad an earthquake is, the Richter scale, and the modified Mercalli scale. The Richter scale is based on the energy from which the earthquake begins, and magnitude based on instrumental records. The Mercalli is based on personal observation.
Earthquakes
Rumble, rumble, rumble,
The earthquake is on its way.
You are going to tumble,
So go away, I say.
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