Plate Tectonics

5. one of the two plates is descending beneath the other
6. a Greek word that means "all the Earth."
8. the study of Earth's magnetic field
9. boundary places where two tectonic plates are moving apart.
13. of plot tectonics which states that Earth's crust and rigid upper mantle are broken into enormous slabs called plates.
14. boundary places where two tectonic plates are moving towards each other.

1. pull the weight of a subduction plate helps pull the trailing lithosphere into the subduction zone.
2. drift proposed that Earth's continents had once been joined as a single landmass.
3. boundary a place where two plates slide horizontally past each other.
4. push the weight of the uplifted ridge is thought to push and oceanic plate toward the trench formed in the subduction zone.
5. spreading states that new ocean crust is formed at ocean ridges and destroyed at deep sea trenches.
7. a device that can detect small changes in the magnetic field
10. a line on a map that connects point that have the same age
11. reversals change in Earth's magnetic field
12. valley when continental crust begins to separate, the stretched crust forms a long, narrow depression.