Across

1. 3noun A large area covered with trees. (6)
2. 6noun A large, slow river of ice. (7)
3. 8verb To make air, water or soil dirty. (7)
4. 10noun The wearing away of rock and soil by wind or water. (7)
5. 13noun A sudden shaking of the ground. (10)
6. 15noun A mountain that can throw out lava. (7)
7. 16adjective Describes energy that will not run out, like solar. (9)

Down

1. 1noun The remains of an ancient plant or animal in rock. (6)
2. 2noun Sand and mud that settle at the bottom of water. (8)
3. 4noun A very large body of salt water. (5)
4. 5verb To explode and throw out lava or ash. (5)
5. 7noun The usual weather of a place over many years. (7)
6. 9verb To turn from a liquid into a gas. (9)
7. 11noun A long period without rain. (7)
8. 12verb To use materials again to make new things. (7)
9. 14adjective Describes air with a lot of water vapor. (5)