Earth Science

2. Earth's thickest layer
4. Molten rock beneath the Earth's surface
8. A theory explaining the structure of the Earth's crust
13. Earth's outermost layer
15. Earth's solid center
16. The layer below Earth's mantle
17. A deep valley that is formed when an oceanic plate collides with a continental plate
19. An opening in the Earth's surface
20. The region where magma breaks through the surface
21. Made up of crust and uppermost mantle

1. Sudden ground-shaking release of built up energy
3. When magma rises to the Earth's surface, pushing rock aside
5. Areas of subduction typically experience large earthquakes
6. Large breaks in rocks
7. Forms the lithosphere
9. Area where molten rock rises to the Earth's surface
10. Volcanoes that occur where magma erupts through long cracks in the lithosphere
11. The region where two tectonic plates are in contact
12. Point on Earth's surface directly above the focus where earthquakes form
14. Partly molten layer in the Earth's upper mantle
18. Steep sided valley formed on land