plate tectonics

3. a continuous underwater mountain range on the ocean floor formed where tectonic places spread apart
5. earths magnetic field preserved in rocks, sediments, and archaeological materials
12. study of earth
13. thickest layer of the earth
14. new ocean floors being created at mid-ocean ridges
15. massive super continent that existed millions of years ago
16. theory that Earth’s continents slowly move over time
17. two tectonic plates move toward each other
18. splitting apart a single tectonic plate into two or more plates separated by divergent plate boundaries
20. who proposed the seafloor spreading hypothesis

1. earth’s continental crust repeatedly assembles into a single supercontinent and then breaks apart and disperses over hundreds of millions of years
2. where plate tectonics are located
4. who proposed the continental drift hypothesis in the early 1900s
6. two tectonic plates slide horizontally past each other
7. molten rock inside of the earths mantle
8. two tectonic plates pull apart
9. thinnest layer of the earth
10. massive slab of rock
11. an area of volcanic activity
19. how many major tectonic plates are there