Across
- 4. A device used to record earthquake waves.
- 5. A boundary in which two plates move toward each other, causing one of the slabs of the lithosphere to subduct beneath an overriding plate.
- 8. The rigid outer part of the earth, consisting of the crust and upper mantle.
- 11. A sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action
- 14. The thick part of the Earth’s crust, not located under the ocean.
- 17. A region where the crustal plates are moving apart.
- 19. A large natural elevation of the earth's surface rising abruptly from the surrounding level; a large steep hill.
- 20. Valley A large elongated depression with steep walls formed by the downward displacement of a block of the earth's surface between nearly parallel faults or fault systems.
Down
- 1. The thin part of the Earth’s crust located under the oceans.
- 2. Soft, weak upper portion of the mantle where the lithospheric plates float and move around.
- 3. A depression in the seafloor produced by subduction process.
- 6. A break in a rock along which movement has occurred.
- 7. The sideways and downward movement of the edge of a plate of the earth's crust into the mantle beneath another plate.
- 9. Spot A concentration of heat in the mantle capable of creating magma.
- 10. tectonic A theory which suggests that Earth’s crust is made up of plates that interact in various ways, thus producing earthquakes, mountains, volcanoes, and other geologic features.
- 12. Rigid sections of the lithosphere that move as a unit.
- 13. A mountain or hill, typically conical, having a crater or vent through which lava, rock fragments, hot vapor, and gas are being or have been erupted from the earth's crust.
- 15. A boundary produced when two plates slide past to each other.
- 16. The outer portion of the Earth.
- 18. The science that studies Earth.