Plate Tectonics

3. Long crack in the surface of the Earth. Where earthquakes usually occur. San Andreas Fault.
6. When two tectonic plates move toards each other and collide. Equal density.
7. 1st theory describing the history of Earth's surface. States that the continents were once connected and have drifted apart.
9. When 2 plates slide past each other. Fault lines
10. Tectonic plates that are at the bottom of the ocean.
14. South America matches up with this continent.
15. scrapes across rocks where a glacier once was.
16. Parallel pattern of rock material found at indetical locations across the Mid-Atlantic Ridge. Reveals rock of the same geological age.
18. huge pieces of lithosphere that slowly move on the asthenosphere. Consists of crusts and uppermost part of mantle.
19. The scietist who is generally credited with the continental drift theory.
20. When two plates move away from each other. Continental = rift valley. Ocean = mid ocean ridge.

1. When a denser plate is pushed down and beneath a less dense plate. Occurs at a convergent boundary. Creates volcanoes and trenches.
2. 2nd theory describing the history of Earth's surface. States that the lithosphere is divided into plates that are moving on top of the asthenosphere.
4. rock formations, rivers, and lakes appear to match up on different continents due to this piece of evidence.
5. seafloor mountain system formed by divergent boundaries
8. The amount of matter in a given space of volume. Oceanic crust is thinner and denser than continental crust.
11. Tectonic plates that lie under surface land masses.
12. super continent that had most of the land masses before it seperated.
13. evidence of dead plants and animals
17. Circular movement of fluids caused by the rising of hotter, less dense fluid and the falling of cooler, denser fluid.