| A | B |
|---|
| Landform | Landscapes that form over millions of years. |
| Core | Central layer of the earth, probably composed of hot iron and nickel, solid in the inner core and molten in the outer. |
| Mantle | Middle layer of the earth, composed of thick hot rock. |
| Crust | Outer layer of the earth. |
| Magma | Melted rock within the earth's mantle. |
| Continent | One of the major land areas of the earth. |
| Plate Tectonics | A theory in geology that the earth's crust is made up of huge, moving plates of rock. |
| Fault | Crack in the rocks of the earth's crust along which movement occurs. |
| Earthquake | Violent jolting or shaking of the earth caused by movement of rocks along a fault. |
| Tsunami | Huge sea wave caused by an earthquake on the ocean floor. |
| Weathering | A process by which surface rocks are broken down into smaller pieces by water, chemicals, or frost. |
| Erosion | Wearing away of the earth's surface, mainly by water, wind, or ice. |
| Plateau | A flat landform whose surface is raised above the surrounding land, with a steep cliff on one side. |
| Isthmus | A narrow piece of land connecting two larger pieces of land. |
| Peninsula | A piece of land surrounded by water on three sides. |
| Strait | A narrow body of water lying between two pieces of land. |
| Atmosphere | A thick cushion of gases surrounding the earth, made up mainly of the gases nitrogen and oxygen. |
