Across
- 2. how old an object is compared to another
- 4. where tectonic plates slide past each other
- 5. where tectonic plates pull apart
- 6. an unstable form of an element
- 8. the use of isotopes to find the absolute age of an object
- 9. an area of the ocean where oceanic plates collide
- 11. what drives the cycling of material in the mantle
- 16. where tectonic plates collide with each other
- 20. a giant wave caused by an earthquake
- 21. the remains or traces of an organism
- 23. between the crust and the core
- 24. the process by which a plate is shoved back into the mantle
- 25. consists of the crust and upper mantle
Down
- 1. the uppermost layer of Earth
- 3. deepest layer of Earth
- 7. a theory that explains that Earth's plates are in constant motion
- 10. the location on Earth's surface above an earthquake
- 12. a break in the Earth's crust
- 13. the exact age of an object
- 14. an area surrounding the Pacific where most volcanoes and earthquakes are located
- 15. the supercontinent that existed long ago
- 17. molten rock
- 18. layer beneath the lithosphere that is semi-solid
- 19. a ridge of undersea mountains
- 22. liquid layer of Earth