Across
- 2. when the ocean floor sinks beneath a deep-ocean trench
- 3. of rock that builds earth's outer skin
- 7. earth's solid outer shell like an egg shell
- 8. 300 million year old supercontinent.
- 10. layer of hot rock
- 12. mountain ranges that ran along the middle of some ocean floors.
- 15. layer of molten metal surrounding the inner core
- 17. adding new material to to the ocean floor.
- 18. a theory that what made in the mid-1960s
- 19. what it's called when plates move apart or diverge
- 20. where earth's crust diverge on land
Down
- 1. what it's called when plates come together or converge
- 4. device that uses sound waves to measure distance to an object.
- 5. scientists idea that continents slowly moved over earth's surface.
- 6. breaks in earth's crust where rocks have slipped past each other
- 9. dense ball of solid metal
- 11. old rock
- 13. deep underwater canyons like what the grand canyon was like long long ago.
- 14. german scientist
- 16. when plates slip past each other