| A | B |
|---|
| earthquakes | the shaking and trembling of the Earth's surface |
| stress | forces that cause rocks to break or bend |
| tension | a force that pulls rock apart |
| compression | a force that pushes rock together |
| shearing | a force that causes rock to push in the opposite directions |
| faults | when rocks break and move along the surface |
| normal fault | rock above the fault line moves down |
| reverse fault | rock below the fault line move up |
| strike-slip fault | rocks slide past one another |
| seismic waveq | energy waves generated by an earthquake |
| focus | point where energy is released by an earthquake |
| epicenter | the point on the Earth's surface directly above the focus |
| primary waves | move from the earthquake focus and travels through solids and liquids |
| secondary waves | only travels through solids |
| surface waves | forms when primary waves and secondary waves reach the surface |
| triangulation | identifies the epicenter of an earthquake |
| seismograph | an instrument to measure earthquake waves |
| transverse waves | another name for secondary waves |
