Across
- 4. earth's outermost layer
- 7. 90% of earthquakes occur inside of this ring
- 8. an instrument used to record the motion of the ground during an earthquake
- 10. there are this many major tectonic plates
- 13. a weaker layer of earth that is beneath the lithosphere
- 14. Alfred Wegener suggested that this was happening to the continents
- 15. a phenomenon caused by the slipping of tectonic plates
- 18. when crust is destroyed as one plate goes under another
- 20. super continent that existed hundreds of millions of years ago
Down
- 1. the solid outer part of earth. It includes the upper part of the mantle and the crust
- 2. when new crust is created as two plates pull away from each other
- 3. when crust is not created or destroyed, as the plates slide past each other horizontally
- 5. last name of the person who proposed "continental drift"
- 6. large pieces of earth's crust and mantle
- 9. a split between two bodies (ex: two plates)
- 11. the centre of the earth
- 12. the proper term for molten rock
- 16. last name of the person who invented the seismic magnitude scale
- 17. formed when lava flows through cracks in the earth
- 19. earthquakes and volcanoes occur along the _____ of plates