| A | B |
|---|
| faults | cracks in the Earth's crust |
| earthquakes | vibrations of rocks moving and breaking |
| compression | the type of force that squeezes or compresses |
| tension | the type of force that causes stretching and elongation |
| shear | the type of force that causes slippage as the rocks move past each other |
| normal fault | the type of fault that is caused by tension |
| reverse fault | the type of fault that is caused by compression |
| strike-slip fault | the type of fault that is caused by shearing |
| seismic waves | the type of energy waves that are produced by an earthquake |
| focus | the point in the Earth's interior where the earthquake's energy is released |
| epicenter | the point on the Earth's surface directly above the focus |
| the primary waves | the seismic waves that cause the particles in rocks to move back & forth |
| secondary waves | the seismic waves that cause the particles in rocks to move up & down |
| surface waves | the seismic waves that cause the most destruction |
| crust | the outer layer of the Earth |
| mantle | hot, flowing solid of the Earth |
| outer core | liquid part of the Earth's core |
| inner core | solid part of the Earth's core |
| seismologist | scientist who studies earthquakes & seismic waves |
| seismograph | the instrument that records the waves of earthquakes |
| magnitude | measuring the strength of the earthquake based on the height of the lines on the seismograph |
| Richter scale | the scale used to express the strength of an earthquake |
| tsunamis | ocean waves produced by earthquakes |
