Plate Tectonics
Across
- 1. supercontinent formed 300 million years ago
- 9. the continents have moved over earth’s surface
- 12. theory of the slow, constant motion of Earth’s plates
- 13. seperating plates
- 14. 3,000 meters of hot, solid rock
- 16. higher density crust sinks beneath a deep-ocean trench
- 17. where the Earth’s crust has broken
- 18. forms when crust diverges on land
- 20. new crust pushes old rock further from mid-ocean ridges
Down
- 2. theorized that the continents slowly moved over the surface of Earth
- 3. underwater mountain range
- 4. remnant of something that existed long ago; preserved in rock
- 5. forms faults
- 6. plates come together
- 7. causes the Earth’s plates to move
- 8. when molten material hardens quickly, these form
- 10. mass divided by volume
- 11. where oceanic crust bends downward
- 15. outer shell of the lithosphere
- 19. measures distance to an object through sound waves