Across
- 5. To plant different crops from year to year.
- 6. A substance in the earth that has never been alive.
- 8. Large mass of moving rock or soil from a mountain or cliff
- 9. A natural formation of rock or soil on the earth's surface is called a ...
- 10. Hot, liquid rock found in the earth's mantle.
- 11. The loss of topsoil by water and wind.
- 14. The first layer of the earth is the ...
- 15. Material in the soil that is made from living things that are broken down or decayed is...
- 16. There are ... continents on the earth.
- 18. The place where a river begins, usually high in the mountains.
- 21. The coldest part of the earth are the...
- 22. Precipitation on land that eventually trickles into streams
- 23. The outer layer of the earth is the...
- 24. The third layer of the earth is the...
Down
- 1. A ditch formed where soil washed away
- 2. The very center of the earth.
- 3. Matter that settles at the bottom of a liquid.
- 4. A place in the earth where magma can erupt as lava.
- 7. The shaking of the earth's crust.
- 12. Water, the right kind of air, and good soil are examples of natural...
- 13. The second layer of the earth is...
- 17. The imaginary line around the earth halfway between the North and South Poles is the...
- 19. The top layer of the earth's crust.
- 20. Soil in which plants grow well
- 22. Seventy percent of the earth is covered by water.