The earth is broken into giant pieces of rock known as plates. These plates form the earth's crust. The plates are always moving slowly and will sometimes bump into each other. Earthquakes may occur when the plates collide. They may also occur far away from these plates at cracks in the earth's surface. These cracks are known as faults. Earthquakes may also happen along fault lines. There are three types of faults: up, down, and sideways.
An earthquake is a sudden shift in the earth's crust. Most earthquakes occur along faults when large blocks of rock break apart and release huge amounts of energy and pressure. This energy is released as shock waves that ripple across the earth's surface. These waves may be felt and measured. Earthquakes are measured using a Richter Scale, which measures the intensity of the shock waves. While some earthquakes may destroy entire cities, others occur unnoticed.
An earthquake is like a stone thrown into the
water. After the stone hits the water waves move outwards from the center.
