D Atkinson

3. The inner most layer of the Earth
4. Rocks formed from sediment
6. Vibrations in the Earth's crust and mantle
12. When continental tectonic plates collide
14. The process of sorting different materials based upon density.
16. 1000 meters
19. When tectonic plates push each other apart
20. Magnetic sphere surrounding the Earth
21. When continental crust and oceanic crust collide and the denser plate subducts

1. The theory for which all contemporary understanding of tectonic plates is based
2. To bend
5. The thickest layer of the earth under the crust
6. A device that measures seismic activity
7. wind Ions from the sun
8. The rise of warmer material and the fall of cooler material
9. The outer most and thinnest layer of the Earth
10. Rock formed by heat and pressure.
11. rock formed via volcanic activity
13. zone of charged particles
15. A weak area in Earth's crust can form islands
17. Study of the Earth's crust
18. When two tectonic plates move past each other horizontally