Across
- 5. / molten rock beneath the earth's surface
- 6. / A shaking or sliding of the ground. It is caused by the sudden movement of masses of rock along a fault or by changes in the size and shape of masses of rock far beneath the earth's surface.
- 8. Boundary / The boundary between two tectonic plates that are moving away from each other
- 10. / extremely deep areas in the ocean that are created by a subducting plate
- 11. Boundary / The boundary formed by the collision of two plates
- 12. / process in which two plates collide and the denser ocean plate descends below the other
- 16. current / this type of energy transfer is believed to drive plate movement
- 18. / The solid, outer layer of the Earth that consists of the the crust and the rigid upper part of the mantle
- 21. spreading / The process by which new oceanic crust forms as magma rises towards the surface and solidifies
- 22. of Fire / a major belt of volcanoes that rims the Pacific Ocean
Down
- 1. / Magma that flows onto Earth's surface; the rock that forms when lava cools and solidifies
- 2. Tectonics / The theory that the earth is broken into plates and are in motion due to convection currents in the asthenosphere
- 3. ridge / an underwater mountain range made at divergent plate boundaries
- 4. Spot / An area where magma from deep within the mantle melts through the crust above it
- 7. / The soft layer of the mantle on which the tectonic plates move
- 9. valley / long, narrow depression formed at divergent boundaries
- 13. Drift / The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations
- 14. / the term for the supercontinent which contained all the plates together
- 15. / A weak spot in the crust where magma has come to the surface
- 17. Boundary / The boundary between tectonic plates that are sliding past each other horizontally
- 19. / The thin and solid outermost layer of the Earth above the mantle
- 20. Wegener / Proposed the continental drift theory in the 1900s