Across
- 3. volcanoes allow ....... to escape the magma chamber
- 5. includes both the crust and upper mantle (uppermost layer of the earth)
- 6. objective measure of the strength of an earthquake
- 7. scientist who studies earthquakes
- 10. places where plates slide sideways past each other
- 12. who proposed the theory of plate tectonics
- 13. instrument that plots the intensity of earthquake waves
- 15. type of volcano named for their broad shield-like profiles
- 16. theory that explains how Earth's continents float slowly on the surface
Down
- 1. places where one plate slides beneath the other
- 2. break or separation in rock
- 4. rupture on crust of Earth
- 8. layer beneath the crust
- 9. point directly above the source of the earthquake
- 11. places where plates pull apart from each other
- 14. amount of energy released from an earthquake