| A | B |
|---|
| seismic waves | waves sent out in all directions from focus |
| focus | point inside the earth where energy is released |
| epicenter | point on Earth's surface directly above the focus |
| earthquakes | when stresses are release & rocks exceed their elastic limit |
| magnitude | measures the energy released by earthquake |
| normal fault | rock slabs are pulling apart |
| reverse fault | rock slabs are pushing together |
| transform fault | rock slabs are moving past each other |
| primary waves-P | waves that move back & forth in same direction |
| secondary waves- S | waves that move up & down in a ropey fashion |
| surface wave-L | most destructive because of up/down & side to side motion |
| seismograph | instrument used to detect vibrations of earthquake |
| seismologist | scientist who study these waves |
| tsunami wave | large sea waves that usually accompany an earthquake at sea |
| faults | slippage of rocks along a fault plane |
| Richter scale | earthquake scale due to the magnitude of earthquake |
| aftershock | shock that occurs after the principle shock of an earthquake |
| tsunami | huge waves that form when earthquakes occur on the ocean floor |
