Plate Tectonics

3. The point on the surface of the Earth directly above the focus of an earthquake.
5. The place within the crust where the energy of an earthquake is centred.
6. A place where extremely hot material from within the Earth erupts to the surface.
8. The process whereby continents break up, subside, and eventually form a new sea.
9. The crust that forms the continents.
11. A transverse seismic wave that fails to pass through the outer-core of the Earth.
12. A seismic wave that travels along the surface of the Earth.
16. Molten rock that has erupted onto the surface of the Earth.
17. Where plates are sliding parallel to each other.
19. Molten rock below the surface of the Earth.
21. The separating and combining of continents by movement across the surface of the Earth.
22. A chain of islands formed at the edges of colliding plates where one plate subducts.
23. A deep channel in the ocean floor where crust is forced downwards.
25. The theory that the crust of the Earth exists as many large pieces that move on the asthenosphere.
26. A layer of plastic semi-solid rock in the lower mantle.
28. The movement of kinetic energy through the Earth.

1. An instrument that measures the seismic waves.
2. The process by which new crust forms to give ocean ridges.
4. Where plates are moving apart from each other.
7. A longitudinal seismic wave that travels fast through the Earth.
10. Isolated areas away from plate boundaries where magma collects within the upper crust.
13. The rapid back-and-forth movement of the ground.
14. Where plates are colliding with each other.
15. A receiver that can detect satellite signals and calculate its position on the Earth's surface.
18. Alternating patterns of magnetism set within rocks.
20. When one plate is forced below another plate during a collision.
24. The crust that forms the ocean floor.
27. A huge wave in the ocean caused by the sudden movement of the sea floor.