Tectonic Plates

4. a landform that rises at least 1,000 feet (300 meters) or more above its surrounding area.
6. when the continents were arranged together as a single supercontinent
8. The man who said that Earth's land masses are in constant motion.
10. a rigid layer of the Earth's crust that is believed to drift slowly
12. the mostly solid bulk of Earth's interior.
15. thin shell on the outside of Earth
17. relating to the ocean.
18. massive slab of solid rock made up of Earth's lithosphere
19. of or relating to the earliest known rocks formed during the Precambrian Eon
20. the movement of continents resulting from the motion of tectonic plates.

1. openings, or vents where lava, tephra (small rocks), and steam erupt onto the Earth's surface.
2. pertaining to the structure or movement of the earth's crust
3. It forms part of the tectonic boundary between the Pacific Plate and the North American Plate.
5. the earliest eon in the history of the Earth from the first accretion of planetary material (around 4,600 million years ago)
7. the chemistry of the earth's crust
9. the denser, weaker layer beneath the lithospheric mantle.
11. subject to or caused by an earthquake or earth vibration
13. the shaking of the Earth's surface resulting from a sudden release of energy
14. the process of covering the earth with glaciers or masses of ice
16. the solid, outer part of Earth.