| A | B |
|---|
| Earthquake | a trembling of the Earth caused by a sudden release of stored energy |
| fault | A crack in the Earth's crust along which some movement has occurred |
| epicenter | point on Earth's surface directly above an Earth quake's focus |
| focus | the true location of an earth quake and source of seismic waves...inside the Earth |
| P-wave | seismic waves that cause matter to stretch and compress; fastest seismic waves |
| S-wave | seismic waves that move matter side to side; slower of the two waves |
| seismograph | an instrument that measures and records seismic waves |
| seismic wave | a vibration produced by an earthquake |
