| A | B |
|---|
| Aftershock | An earthquake that occurs after a larger earthquake in the same area |
| Tsunami | A giant wave caused by an earthquake on the ocean floor |
| Liquefaction | The process by which an earthquakes violent movement suddenly turns loose soil into liquid mud |
| Earthquake | Is a shaking and tremblinng that results from the movement of rock beneath Earth's surface |
| Deformation | Any change in the volume or shape of Earth's crust |
| Tension | Pulls on the Earth's crust stretching rocks so that it becomes thinner in the middle |
| P Waves | Earthquake waves that compress and expand the ground like an accordion |
| Focus | Is the point beneath Earth's surface where rock is under stress breaks, triggering an earthquake |
| Epicenter | The point on the surface directly above the focus |
| Geologists use instruments to measure | deformation and stress along faults |
| Scientists determine earthquake risk by | monitering active faults and b studying faults where past earthquakes have occured |
| Plateau | Is a large area of flat land elevated high above sea level |
| Folds | Are bends in rock that form when compression shortens and thickens part of Earth's crust |
| Footwall | The block of rock that forms the lower half of a fault |
| Shearing | Stress that pushes a mass of rock in opposite directions |
| Magnitude | The measure of a earthquakes strength based on seismic waves and movement along faults |
| Anticline | An upword fold in rock formed by compression of Earth's crust |
| S Waves | A type of seismic wave that moves the ground up and down or side to side |
| Richter Scale | A scale that rates seismic waves as measured by a mechanical seismograph |
