Plate Tectonics
Across
- 4. a theory that the middle of the ocean is spreading apart, forming new oceanic crust
- 9. a deep valley that forms as a result of tectonic plates moving apart on land
- 10. two plates moving apart
- 14. tiny currents that carry thermal energy
- 17. an instrument that records the motions of the Earth, especially earthquakes
- 18. relating to earthquakes
- 19. the maximum height of a wave crest or depth of a trough
- 20. an area in the middle of a lithospheric plate where magma rises from the mantle and erupts at the Earth's surface
- 22. an abrupt movement of soil and bedrock downhill in response to gravity
- 23. the opening at the Earth's surface through which volcanic materials erupt
- 25. rock that in its molten form issues from volcanos
- 27. the supercontinent that existed 335 million years ago
- 30. the place where two or more plates in the Earth's crust meet
- 31. a sudden violent shaking of the ground
- 32. a scientist who studies earthquakes
- 36. a written record of an earthquake, recorded by a siesmograph
- 37. the man who established the theory of continental drift
- 38. semiliquid rock found beneath the earth's surface
- 39. a deep ditch under the ocean along a tectonic plate boundary
- 42. two plates moving towards each other
- 44. a geologist that uses physical principles to study the properties of the earth
- 45. a fracture in rock where movement has occurred
- 46. the gradual movement of the continents across the earth's surface as a result of the movement of the plates they lie on
Down
- 1. the layer of the earth below the crust
- 2. an exceptionally large ocean wave, especially one caused by an underwater earthquake or volcanic eruption
- 3. one plate sliding against another
- 5. a region in which earthquakes are known to occur
- 6. the regions of the Earth where living organisms exist
- 7. stream of molten rock that erupts relatively nonexplosively from a volcano and moves slowly downslope.
- 8. the system used to measure the strength of an earthquake
- 11. the movement of one tectonic plate under another tectonic plate
- 12. underwater cliffs between the beach and ocean
- 13. relating to eruptions of gas and lava from the Earth's crust
- 15. one of the large landmasses of the earth
- 16. a single thickness of some substance or material
- 21. an active volcano that is in repose but is expected to erupt in the future.
- 24. the degree of hotness or coldness
- 26. an underwater earthquake
- 28. the strength of an earthquake
- 29. outer layer of the earth
- 33. a landform where molten rock erupts through the surface of the planet
- 34. a risk
- 35. pieces of the earth's crust
- 40. the centre of the earth
- 41. a measure of the effects of an earthquake at a particular place on humans, structures and (or) the land itself
- 43. a series of underwater mountains that form as a result of tectonic plates moving apart and allowing magma to rise to the surface