Chapter 7 Crossword

5. Who was the scientist who created the hypothesis of continental drift?
6. What is the solid, outer layer of the Earth that consists of the crust and the rigid, upper mantle?
7. What layer of the Earth is made of solid rock that flows very slowly?
8. What is they theory that the Earth's lithosphere is divided into tectonic plates that move on top of the asthenosphere?
10. When the Earth's magnetic poles change places, what is the change called?
11. Which boundary is formed by the collision of two lithospheric plates?
13. the process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies?
15. 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)
18. What is a substance composed of two or more elements?

1. Where is the place where sea-floor spreading takes place?
2. What layer of the Earth is 2,550 kilometers thick?
3. What kind of waves are produced during an earthquake?
4. What system is used for measuring the rate of tectonic plate movement?
9. What layer of the Earth is 5-100 kilometers thick?
11. What is the hypothesis that states the continents once formed a single landmass, broke apart, and drifted to their present location?
12. What layer of the Earth is the largest?
13. What machine measures and records earthquakes?
14. What was the name of the landmass that was made of all of our present day continents?
16. What layer of the Earth is mainly iron?
17. Pangaea split in two big pieces called Gondwana and what?