Across
- 6. a supercontinent that existed long ago
- 7. the center of earth
- 8. the hard oter layer of earth
- 10. cycle, when continents join together and break apart over time
- 11. ocean the middle part of the oceanic crust cycle, when continents join together and
- 13. when new ocean crust forms and moves outward
- 16. the huge ocean that surrounded Pangaea
- 17. apart over time
- 20. whens earths crust pulls apart and cracks
Down
- 1. boundaries a plpace where plates move toward each other
- 2. long mountains found on the ocan floor
- 3. the theroy that earths surface is made of moving plates
- 4. when new ocean floor forms at ridges
- 5. Magnetic clues in rocks that show how earth changed
- 9. the idea that continets move slowy
- 12. a flat step like area of land
- 14. the thin outer layer of earth
- 15. a place where plates slide past each other
- 18. the soft layer under earths plates
- 19. the thick layer of rock under the crust