Richter scale-used to measure earthquakes.

Fault-a break in Earth's crust where movement of rock occurs.

Fault zone-a place along plate boundaries where many faults are located.

Focus-the point below Earth's surface where movement of rock produces an earthquake.

Fore shock-a small earthquake that precedes a larger earthquake.

Seismic wave- a vibration that travels through Earth carrying the energy released during an earthquake.