CH 9 ES

3. The study of the record of Earth’s magnetic field preserved in rocks, providing evidence for plate movement.
5. A long chain of underwater mountains where new oceanic crust is formed as plates move apart.
7. A system that uses sound waves to measure water depth and map the ocean floor.
9. The process by which new ocean crust forms at mid-ocean ridges and moves outward as plates diverge.
11. A chain of volcanoes that forms on a continent near a subduction zone where an oceanic plate sinks beneath a continental plate.
13. A plate boundary where two plates slide past each other horizontally without creating or destroying crust.

1. A supercontinent that contained all of Earth’s landmasses before they broke apart and drifted to their current locations.
2. A plate boundary where two plates move toward each other, often resulting in subduction or mountain building.
3. One of the large, rigid pieces of Earth’s lithosphere that move over the asthenosphere.
4. A plate boundary where two plates move away from each other, allowing magma to rise and create new crust.
6. A valley that forms on land or along the ocean floor where tectonic plates are pulling away from each other.
8. The theory that Earth’s lithosphere is broken into plates that move and interact, causing earthquakes, volcanoes, and mountain formation.
10. A long, narrow, deep depression in the ocean floor formed where one tectonic plate sinks beneath another.
12. The process in which a denser tectonic plate sinks beneath a less dense plate and returns to the mantle.