Plate Tectonic

3. Wegener's hypothesis that Earth's continents were joined as a single land mass about 200 million years ago.
6. Device used to map the ocean floor that detects small changes in magnetic fields.
8. States that Earth's crust and upper mantle are broken into plates.
11. A person who introduced a plate tectonic theory.
12. It is the rigid, outermost shell of a rocky planet
15. Ancient landmass made up of all the continents that began to break apart about 200 million years ago.
16. It is a layer at the top of the Earth's surface.
17. The weight of the uplifted ridge is thought to push an oceanic plate toward the trench formed at the subduction zone.
18. Study of Earth's magnetic record using data gathered from iron-bearing minerals in rocks.

1. a vent in the earth's crust through which lava, steam, ashes, etc., are expelled
2. where new crust is generated as the plates pull away from each other.
4. Line on a map that connects points of the same age.
5. a series of vibration induced in the Earth's cru
6. Changes in Earth's magnetic field over geologic time.
7. It is hot regions of Earth's mantle where high-temperature plumes of mantle material rise toward the surface.
9. where crust is neither produced nor destroyed as the plates slide horizontally past each other.
10. Hess's theory that new ocean crust is formed at mid-ocean ridges and destroyed at deep-sea trenches
13. process by which one tectonic plate slips beneath another tectonic plate.
14. The weight of a subducting plate helps pull the trailing lithosphere into subduction zone.
19. It is a layer under the crust.