Taylor Dunivan

3. spreading=states that new ocean crust is formed at ocean ridges and destroyed at deep sea trenches.
6. =the study of Earth's magnetic field
8. pull=the weight of a subduction plate helps pull the trailing lithosphere into the subduction zone.
12. push=the weight of the uplifted ridge is thought to push and oceanic plate toward the trench formed in the subduction zone.
13. drift=proposed that Earth's continents had once been joined as a single landmass.
14. boundary=places where two tectonic plates are moving apart.

1. of plot tectonics=which states that Earth's crust and rigid upper mantle are broken into enormous slabs called plates.
2. valley=when continental crust begins to separate, the stretched crust forms a long, narrow depression.
3. of the two plates is descending beneath the other
4. boundary=a place where two plates slide horizontally past each other
5. Greek word that means "all the Earth."
7. a device that can detect small changes in the magnetic field
9. line on a map that connects point that have the same age
10. boundary=places where two tectonic plates are moving towards each other.
11. reversal= a change in Earth's magnetic field