Plate Tectonics
Across
- 2. most layer of earths surface
- 5. layer of earths surface, composed mostly of silicon, oxygen, magnesium, and iron
- 7. ridges/where new ocean crust is formed
- 9. sea trenches/where ocean crust is destroyed
- 10. magma forced upward mantle at mid-ocean ridges produce seafloor
- 12. boundary/place where two plates move together
- 13. tectonics/theory that states that earths crust and upper mantle are broken into sections, which move around on a special layer of the mantle
- 14. large landmass hypothesized to have broken apart about 200 million years ago into continents
- 15. layer of earths surface made up of the crust and a part of the upper mantle
- 16. people to consider the moving of landmasses
- 17. rate that south america is moving away from Africa
- 19. current/cycle of heating, rising, cooling, and sinking
Down
- 1. valley/long, narrow depression
- 2. drift/hypothesis that the continents have moved slowly to their current locations
- 3. wegner/his hypothesis was the continental drift
- 4. the earth/pangaea means
- 6. layer of earth's surface below the lithosphere
- 8. boundary/boundary between two plates that are moving apart
- 11. boundary/plate boundary that occurs when two plates slide past one another
- 13. of earths crust and upper mantle
- 18. Hess/proved Alferd Wegners hypothesis