Plate Tectonics
Across
- 5. innermost layer of Earth
- 8. When two plates come together
- 9. liquid layer made of iron and nickel
- 13. Thin shell on the outside of Earth.
- 14. Earth's layer of silicate rock between the crust and the outer core
- 16. when two tectonic plates move away from each other
- 17. On Earth, it is composed of the crust and the portion of the upper mantle
- 18. the outermost layer of Earth's lithosphere that makes up the planet's continents
- 19. proposed "Continental Drift" in 1912
- 20. quantity per unit volume
Down
- 1. His theroy was that sedimentary layers are deposited in a time sequence with the oldest on the bottom and youngest on the top.
- 2. A supercontinent that existed around 310 million years ago
- 3. motion is predominantly horizontal
- 4. a revolutionary theory explaining that continents shift position on Earth's surface
- 6. His theory was that the states were once together, but they were spread apart by the earthquakes and floods
- 7. the outermost layer of Earth's lithosphere that is found under the oceans
- 10. a seafloor mountain system formed by plate tectonics
- 11. a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity
- 12. region of the upper mantle of Earth. It lies below the lithosphere
- 15. lowland region that forms where Earth's tectonic plates move apart, or rift