| A | B |
|---|
| epicenter | the point on earth's surface above where an earthquake starts |
| focus | the point where an earthquake starts |
| seismic waves | the energy of earthquakes |
| Primary Wave | seismic wave that compresses and expands the ground |
| Secondary Wave | seismic wave that moves the ground side to side |
| Surface/L Wave | seismic wave that moves in all directions |
| fault | crack within a plate |
| plate boundary | where most earthquakes occur |
| aftershock | an earthquake that occurs after the main quake |
| liquefaction | shaking of soil that brings the water from underground to the surface |
| tsunamis | a wave caused by an earthquake |
