| A | B |
|---|
| compression | squeezes rock until it folds or breaks |
| moment magnitude scale | measures the total energy released by an earthquake |
| Normal fault | where tension pulls rock apart and the fault is at an angle |
| hanging wall | the block of rock above the fault in a normal fault |
| stress | a force that works on rock to change its shape or volume |
| Shearing | stress that pushes a mass of rock in two opposite directions |
| strike slip fault | a fault where rock moves sideways with little up or down motion |
| tension | stretches rock so that it become thinner in the middle |
| syncline | a downward fold in a rock caused by compression |
| anticline | an upward fold in rock caused by compression |
| plateau | a large area of flat land elvated high above sea level |
| Footwall | the rock that lies below the fault |
| Earthquake | the shaking and trembling that results from rock moving beneath the earth's surface |
| Focus | the point under earth's surface where rocks breaks causing an earthquake |
| epicenter | the point on earth directly above the focus |
| P waves | compressand expand like an accordion |
| S waves | Vibrate side to side and up and down |
| surface waves | can roll earth's surface like an ocean wave |
| mercalli scale | rates an earthquake's damage |
| richter scale | measures an earthquakes magnitude |
| magnitude | a number scientists give an earthquake to measure its size |
| seismograph | measures and records seismic waves |
| reverse fault | where compression pushes rock together |
