plate tectonics

2. the theory that explains how large pieces of the earths crust move and change shape
4. the sinking of regions of the earths crust to lower elevations
7. soft plastic-like layer of the mantle on which the tectonic plates move
8. a break in a body of rock along which one block slides relative to another
9. the thickest layer of the earth
10. the inner most layer of the earth
11. these make a new seafloor, rift-valleys, etc.
14. strong, lower part of the mantle between the asthenosphere and the outer core
16. the layer of the earth that we live on
18. alfred wegner
20. this creates mountains, treches, earthquakes, etc.

1. tectonic plates slide past each other resulting in earthquakes
3. solid outer layer that consists of the crust and the rigid upper part of the mantle
5. stress that occurs when the forces act to squeeze an object
6. properties that involve a reaction to an applied load strength, ductility, hardness, impact resistance, and toughness
12. Harry Hess came up with this idea
13. this layer of the earth takes up 33% of the the earth
15. core the only liquid layer of the earth
17. the nature of somethings ingredients
19. plate there are 10 of these on earth