Across
- 3. how much mass there is in a given amount of volume
- 4. a mountain that erupts
- 7. underwater ocean ranges
- 9. pieces of earth separated by cracks
- 11. german scientist who discovered that the continents were together at one point
- 14. the uppermost part of the mantle
- 15. plates collide
- 17. plates slip past eachother
- 18. a large body of water
- 19. forms when pieces of earth's crust diverge on land
- 21. a process where the ocean floor sinks in the mantle
Down
- 1. a supercontinent that existed 2 million years ago
- 2. any trace of an ancient organism preserved in rock
- 5. - an idea that continents slowly move
- 6. earth's plates that are in slow constant motion
- 8. plates come together
- 10. a process that adds new material to the ocean floor
- 12. a layer of hot rock
- 13. deep underwater canyons
- 16. heat transfer from air currents
- 20. breaks in the earth's crust