Plate Tectonics

4. a plate boundary where tow plates move away from each other
5. a plate boundary where two plates move past each other in opposite directions
7. the hypothesis that the continents slowly move across Earth's surface
8. the name of the single landmass that broke apart 200 million years ago and gave rise to today's continents
10. a deep valley that forms where two plates move apart

1. a plate boundary where two plates move toward each other
2. the process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
3. a deep valley along the ocean floor through which oceanic crust slowly sinks towards the mantle
6. a rigid layer made up of the uppermost part of the mantle and the crust
9. a break in Earth's crust where slabs of rock slip past each other