Plate Tectonics

3. the direct transfer of energy through space by electromagnetic waves
4. the hypothesis that the continent slowly move across Earth's surface
5. the force exerted on a surface divided by the total area over which the force is exerted
9. the amount of mass of a substance in a given volume; mass per unit volume
11. the process by which molten material adds new oceanic crust to the ocean floor
13. a rigid layer made up of the uppermost part of the mantle and the crust
15. Vibrations that travel through Earth carrying the energy released during an earthquacke
17. the layer of rock that forms Earth's outer surface
18. a dark, dense, igneous rock with a fine texture, found in oceanic crust
19. a break or crack in Earth's lithosphere along which the rocks move
20. a usually light-colored rock that is found in continental crust
21. the layer of hot, solid material between Earth's surface and core

1. the theory that pieces of Earth's lithosphere are in constant motion, driven by continental currents in the mantle
2. a large stream of moving water that flows through the oceans
6. a well-tested concept that explains a wide range of observations
7. a plate boundary where two plates move past each other in opposite directions
8. a plate boundary where two plates move toward each other
10. the soft layer of the mantle on which the lithosphere floats
12. a plate boundary where two plates move away
14. the name of the single landmass that broke apart 200 million years ago and broke into today's continents
16. the direct transfer of thermal energy from one substance to another substance that it's touching