| A | B |
|---|
| focus | point beneath Earth's surface where rock breaks under stress and triggers an earthquake |
| plateau | large area of flat land that is elevated above sea level |
| Mercalli Scale | tells how much damage was done |
| compression | produces reverse faults |
| shearing | stress that pushes a mass of rock in opposite directions |
| P Waves | waves that arrive at the surface first and move by compressing and expanding the ground |
| footwall | in a normal fault the part that is below the hanging wall |
| Strike slip fault | rocks slip past each other sideways |
| anticline | fold in rock that bends upward into an arch |
| tension | stress force that pulls two plates apart |
| fault-block mountain | two normal faults drop down on either side of a block of rock |
| S waves | secondary waves |
| seismic waves | vibrations that move through the ground carrying the energy released during an earthquake |
| compression | squeezing together of rocks from stress |
| hanging wall | the block of rock that lies above a fault |
| Moment Magnitude Scale | estimates energy released by an earthquake |
| Surface Waves | move slower than P and S waves |
| Richter Scale | earliest scale for measuring magnitude of an earthquake |
| syncline | layers of rock that bend and form a dowward fold |
| reverse fault | compression causes the hanging wall to move over the foot wall |
