| A | B |
|---|
| core | area at the center of the Earth, which includes a solid inner core and a hot liquid outer core |
| mantle | layer of hot, dense rock about 1,770 miles (2,850 km) thick between the Earth's core and crust |
| magma | hot, melted rock that sometimes flows to the earth's surface in a volcanic eruption |
| crust | Earth's upper layer; a thin rocky shell that forms the surface of the Earth |
| continents | seven large land areas |
| plate tectonics | theory that explains how continents were formed and why they move |
| earthquake | sudden and violent movements of the Earth's crust |
| tsunami | huge sea wave caused by an earthquake on the ocean floor |
| faults | cracks in the Earth's crust |
| weathering | when water, ice, chemicals and/or plants break rocks into smaller pieces |
| erosion | when water, wind, and/or ice move away weathered material |
| glacier | giant slow-moving sheets of ice |
| accumulate | to increase in amount; to collect or gather |
| release | set free; relieve or reduce pressure |
| constant | happening a lot or all of the time |
