| A | B |
|---|
| Pangea | super continent that existed 200 million years ago |
| glacier | moving river of ice and snow |
| Alfred Wegener | scientist who thought that the continents were once one super continent |
| fossil | the remains of trace of a living thing that has been preserved |
| sea-floor spreading | theory that new ocean crust is formed at the mid ocean ridges by molten lava |
| continent | a large mass of land |
| lithosphere | crust and upper mantle |
| mantle | warm, flowing layer of the Earth located between the crust and core,the largest layer inside Earth |
| crust | outer most layer of Earth |
| inner core | solid core composed of dense iron and nickel |
| outer core | liquid core composed of iron and nickel |
| asthenosphere | plastic layer below the lithosphere |
| plates | large sections of Earth's crust and upper mantle, lithosphere |
| plate tectonics | theory that Earth's crust and upper mantle are broken into sections |
| continental drift | theory that the continents move |
| divergent boundary | boundary between two plates that are moving apart |
| convergent boundary | boundary where two plates are moving toward each other |
| transform fault boundary | boundary where two plates are moving past each other |
| convection current | cycle of heating, rising, cooling and sinking |
| subduction zone | area where a denser converging plate desends or sinks under a less dense converging plate |
| earthquake | the movement of Earth's crust as a result of the build up of friction between two lithospheric plates |
| mid-ocean ridge | example of a divergent boundary in ocean crust |
| erosion | the process of moving sediment by wind, water, ice, or gravity |
| lava | molten rock that has reached the Earth's surface |
| magma | molten rock inside the earth |
| volcano | vent through which molten rock reaches the earth's surface and the pile of material around the vent |
| weathering | the process of breaking down rocks and minerals |
