| A | B |
|---|
| landform | a natural feature on Earth's surface |
| mountain | an area that is higher than the land around it |
| valley | a lower area with higher land around it |
| canyon | a valley with steep walls |
| topography | the shape of landforms in an area |
| plateau | a flat area higher than the land around it |
| plain | a large flat landform |
| delta | form at the ends of rivers with bits of soil and rock |
| dunes | form in dry areas where wind carries sand |
| coral | islands that form from the remains of tiny sea animals |
| crust | Earth's thin outer layer |
| mantle | the rock layerj below the crust |
| core | the Earth's center |
| volcano | a mountain that forms as lava flows through a crack onto Earth's surface |
| earthquake | the shaking of Earth's surface caused by movement of rock in the crust |
| fault | a break in the crust |
| strike-slip | slabs of rock sliding past eachother |
| deposition | when a river drops bits of rock and soil along the way |
| glacier | a large moving mass of ice |
| fossil | the remains or traces of an organism that lived long ago |
| petrified wood | wood of a tree that has been replaced by rock |
| mold | a shaped hole in rock that forms after an organism decays |
| cast | when a mold filles with minerals |
| fossil record | information about Earth's history that is contained in fossils |
| geologic time scale | a timeline used to understand what was living during each part of history |
| magnitude | the measured strength of an earthquake |
| Richter scale | a number system that is used to measure the strength of an earthquake |
| P-waves | Primary Waves |
| S-Waves | Secondary Waves |
| surface waves | earthquake waves that move along the surface of earth |
| aftershock | a small earthquake that occurs days or even months after a larger quake |
