Across
- 3. a number of rigid but moving pieces of the Earth's surface
- 4. forms when two plates slide past each other
- 5. a theory suggesting that continents move
- 8. zone of weak, plastic like material in the mantle
- 9. forms when two plates come together
- 13. slippage along a fault
- 15. theory that explains changes in Earth's crust by internal forces
- 16. movement along break in rock
- 17. states that youngest rocks of ocean floor are at diverging boundaries, moving outward
- 20. force behind earthquakes
Down
- 1. rigid blocks of Earth's crust and upper mantle
- 2. forms when two plates move apart
- 6. produced as a plate moves deeper into the mantle
- 7. boundaries at which plates move past one another horizontally
- 10. point directly above an earthquake
- 11. slow-moving seismic action
- 12. energy of motion
- 14. region where a plate descends
- 18. area of rigid blocks of Earth's crust and upper mantle
- 19. fast-moving seismic wave