Across
- 3. What machine measures and records earthquakes?
- 6. What is a substance composed of two or more elements?
- 7. waves/ What kind of waves are produced during an earthquake?
- 10. Wegener/ Who was the scientist who created the hypothesis of continental drift?
- 11. tectonics/ What is they theory that the Earth's lithosphere is divided into tectonic plates that move on top of the asthenosphere?
- 13. What is the solid, outer layer of the Earth that consists of the crust and the rigid, upper mantle?
- 18. spreading/ the process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies?
- 19. Pangaea split in two big pieces called Gondwana and what?
- 20. What layer of the Earth is 5-100 kilometers thick?
Down
- 1. reversals/ When the Earth's magnetic poles change places, what is the change called?
- 2. layer of the Earth is made of solid rock that flows very slowly?
- 4. What layer of the Earth is 2,550 kilometers thick?
- 5. drift/ What is the hypothesis that states the continents once formed a single landmass, broke apart, and drifted to their present location?
- 8. What layer of the Earth is mainly iron?
- 9. What layer of the Earth is the largest?
- 12. boundary/ Which boundary is formed by the collision of two lithospheric plates?
- 14. What was the name of the landmass that was made of all of our present day continents?
- 15. plate/ What is a block of lithosphere that consists of the crust and the outer most part of the mantle?(hint: floats on top of the astenosphere)
- 16. positioning unit/ What system is used for measuring the rate of tectonic plate movement?
- 17. ridge/Where is the place where sea-floor spreading takes place?