| A | B |
|---|
| Earth's Composition | Constructed of crust, mantle and core |
| Density | The 3 layers of the Earth are separated by what |
| Earth's Structure | Composed into 5 layers based on its physical properties |
| Lithosphere | Outermost structural layer of the Earth |
| Asthenosphere | Layer of weak, warm rock that flows slowly |
| Lower Mantle | Lowest portion of the mantle |
| Outer Core | A hot shell of hot, liquid metal beneath the mantle |
| Inner Core | A solid sphere of hot metal, mostly iron |
| Continentl Drift | A hypothesis that states that the world's continents move slowly over the Earth's surface |
| Seafloor Spreading | The process by which new lithosphere is created at midocean ridges |
| Magnet Strips | Evidence for seafloor spreading |
| Plate Tectonics | States that the lithosphere is divided into pieces called tectonic plates that move about on top of th asthenosphere |
| 2nd Law of Thermodynamics | Explains how the Earth's plates move |
| Plate Boundries | Three types: divergent, convergent and transform |
| Earthquake | When stressed rock breaks loose |
| Tsumani | Huge sea wave caused by plate movement |
| Volcano | A mountain that forms where lava or magma pile up arount a vent |
