Across
- 2. contain large areas of stable rock
- 4. boundary boundary in which two plates slide past each other horizontally
- 6. single large ocean that covered earths surface during the time the supercontinent
- 7. cycle form an break apart over time
- 8. the study of magnetic properties of rock
- 10. boundary 2 plates move away from each other
- 12. drift a germen scientist names Alfred Wegener proposed a hypothesis
- 15. terranes may be small volcanic or underwater valcaones
- 17. rigid upper part of the mantle form a layer of earth
- 18. process in which continents break apart
- 19. ridge undersea mountain range through the center of which run steep, narrow valleys
Down
- 1. exposed at earths surface
- 2. boundaries plate boundaries that form where 2 plate collide
- 3. piece of lithosphere that has a unique geologic history that differs from the history of the surrounding lithosphere
- 5. continents arranged into large landmasses
- 9. layer of plastic rock just below the lithosphere
- 11. terrane becomes part of a continent
- 13. form on top of seamounts
- 14. formed over 30 million years ago
- 16. spreading new ocean floor forms when magma rises to earths surface and solidifies at a mid ocean ridge