TECTONIC PLATES

3. A section of the lithosphere that slowly moves over the asthenosphere carrying pieces of continental and oceanic crust.
5. A layer of molten iron and nickel that surrounds the inner core of Earth. (2 words)
7. At or near the middle.
8. The point or line where one region ends and another begins.
10. Continents moving over Earth's surface. (2 words)
15. The layer of hot solid material between Earth's crust and core.
16. Move together.
18. A rigid layer made up of the uppermost part of the crust.
19. Under or below.
20. The outer layer of Earth.

1. Move apart.
2. The supercontinent that was pulled apart by continental drift.
4. A large piece of land.
6. The process by which the ocean floor sinks beneath a deep ocean trench and back into the mantle.
9. An undersea mountain chain where new ocean floor is produced. (3 words)
11. Part of Earth's lithosphere that surfaces in ocean basins. (2 words)
12. The soft layer of the mantle on which the lithosphere floats.
13. A dense sphere of solid iron and nickel at the center of the Earth (2 words)
14. The scientist who discovered continental drift.
17. The study of physical Earth, the rocks of which it is composed and the process by which they change.