Presentation on theme: "By: Kjerstin Olsen Earthquakes are usually caused when rock underground suddenly breaks along a fault."— Presentation transcript:
By: Kjerstin Olsen
Earthquakes are usually caused when rock underground suddenly breaks along a fault.
This sudden release of energy causes the ground to shake.
When two blocks of rock or two plates are rubbing against each other they stick. The rocks do not slide smoothly, they catch on each other. After a while, the rocks break because of all the pressure built up. When the rocks break, an earthquake occurs.
The spot underground is called the focus of the earthquake.
The plate directly above the focus, the area on the surface, is called the epicenter of an earthquake.