Plate Tectonics

2. The supercontinent that existed during the late Paleozoic and early Mesozoic eras.
3. A tectonic plate that lies beneath a continent.
6. The sideways and downward movement of the edge of a plate of the Earth's crust into the mantle beneath another plate.
8. A boundary where two tectonic plates slide past each other horizontally.
9. A tectonic plate that lies beneath an ocean.
11. Spreading: The process by which new oceanic lithosphere forms as magma rises to the surface and solidifies.
14. An underwater mountain range, part of the global oceanic ridge system.
15. The theory that the Earth's continents have moved over time.

1. A boundary where two tectonic plates move toward each other.
4. The rigid outer part of the Earth, consisting of the crust and upper mantle.
5. A boundary where two tectonic plates move away from each other.
7. Tectonics: The theory that Earth's outer shell is divided into several plates that glide over the mantle.
10. An opening in the seafloor from which geothermally heated water discharges.
12. This scientist proposed the theory of continental drift.
13. A long, narrow, steep-sided depression in the ocean floor.