PLATE TECTONICS

3. An opening in earths surface where magma and other materials are released.
8. The point on earths surfaces above where an earthquake starts.
9. Mountain ridges run along the seafloor.
10. A layer of earth between the crust and outer core, which is divided into upper and lower sections.
14. An instrument that measures and records ground vibration.
15. WAVES The vibration caused by the release of energy during an earthquake.
18. The process of denser crust of a tectonic plate sliding beneath less dense crust of another plate; occurs at convergent plate boundaries and produces deep sea trenches.
21. The process by which magma rises to the surface at mid-ocean ridges and forms new ocean crust.
22. For earthquakes, a number that represents strength.
23. The lithosphere is divided into large plates that interact with one another and cause geological activity.
24. is the gravitational and subduction-induced pulling of a tectonic plate.

1. Is the point at which two tectonic plates collide.
2. Is the separation of two tectonic plates.
4. Occurs when two rocks are pressed together and one block rides up to overlay the other.
5. Two tectonic plates slide horizontally past each other.
6. Is a current in the mantle that occurs when cooler, denser material sinks and warmer, less dense material rises.
7. In mid ocean ridges a valley that runs along the centre of the ridge.
11. The belief that the Earth's continents have been in the same place since the Earth's formation.
12. A ground-shaking release of energy caused by a break in the crust.
13. A devastating catastrophe caused by geological processes
16. In earth science, the location within earth where an earthquake starts.
17. A large break in a rock.
19. Deep valleys on the seafloor.
20. When new material at mid-ocean ridges pushes older material aside, tectonic plates shift.