| A | B |
|---|
| Trench | A V-shape valley on the ocean floor where old ocean floor is subducted |
| Convection Current | A movement of material caused by differences in temperature |
| Ocean Floor Spreading | The process in which old ocean floor is pushed away from a midocean ridge by the formation of new ocean floor |
| Mantle | the layer of the Earth that extends from the bottom of the crust to the core |
| Ring of Fire | The earthquake and volcano zone that encircles the Pacific Ocean |
| Fault | A break or crack along which rocks move |
| Pangaea | the single giant landmass that existed more than 200 million years ago and that gave rise to the present-day continents |
| Convergent | A plate boundary at which plates come together |
| Divergent | A plate boundary at which plates move apart |
| Magma | Molten rock beneath the Earth's surface |
