Plate Tectonics

5. These are created when magma cools immediately once erupted from the ridge.
9. Movement in a gas or liquid in which the warmer parts move up and the cooler parts move down.
12. The remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.
16. What landform is made when two continental plates collide?
17. This part of the Earth contains our crust and the upper part of the mantle.
18. ________ theorized the continents moved.
19. What did scientists use to map out the sea floor?

1. A break in the Earth's crust.
2. ______ dense materials rise.
3. Stitched looking mountain ranges on the seafloor.
4. This boundary slides.
6. Changes in what affect the ocean floor?
7. The ocean floor is brand new every 200 _____ years.
8. The supercontinent that formed about 200 million years ago.
9. Subduction and seafloor spreading act like a ______.
10. Energy caused by the sudden breaking of rock within the earth or an explosion.
11. The _______ has convection currents which cause continental drift.
13. The crust is ________ dense farther from the mid- ocean ridge.
14. Where does oceanic crust bend downward in the ocean floor?
15. This boundary divides.