1. Changes to Land

2. Landforms Features on the surface of the earth such as mountains, hills, dunes, oceans and rivers

3. Delta A triangle shaped landform at the mouth of a river as it empties into another body of water

4. Canyon A deep gorge in the surface of Earth formed by the erosion of moving water and sand

5. Sand Dune Hills formed by the wind blowing sand

6. Mountain Very large rock formation with peak at top

7. Hill A large land formation of rocks, dirt, and grass that has rounded at the top

8. Valley The flat area between two mountains or hills

9. Glacier Slowly moving river of ice

10. Plain A large area of land that is flat with no mountains, hills, or valleys

11. Erupt To break open suddenly

12. Volcano A mixture of hot rocks, ash, and gases that blows through a crack in the Earth’s surface

13. Landslide The rapid downward slide of rocks and mud

14. Earthquake A sudden release of energy under the Earth's surface that makes the ground shake or crack

15. Channel the bed where a natural stream of water runs; the deeper part of a river or harbor; a narrow sea between two close landmasses.

16. Basin a hollow or depression in the earth’s surface, wholly or partly surrounded by higher land (such as a river basin).

17. Plateau a raised area of land that is relatively flat on top but is higher than the surrounding land.