Science Vocabulary

6. boundary A plate boundary where two plates move away from each other
9. The preserved remains or traces of an organism that lived in the past
10. drift The hypothesis that the continents slowly move across Earth's surface
11. The super continent that broke apart 200 million years ago

1. A break in Earth's crust along which rocks move
2. The process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
3. boundary A plate boundary where two plates move toward each other
4. ridge An undersea mountain chain where new ocean floor is produced
5. spreading The process where molten material adds new oceanic crust to the ocean floor
7. boundary A plate boundary where two plates move past each other in opposite directions
8. valley A deep valley that forms where two plates move apart
11. tectonics The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle