Across
- 3. Unit of geologic time into which a period is divided
- 4. Opening on Earth's surface where magma is forced up and out
- 5. Liquid core that surrounds Earth's solid inner core
- 7. Sea floor spreading causes a ________ inthe ocean floor
- 8. Measure of earthquake's energy
- 10. Unit of geologic time that includes 2 or more periods
- 11. Layer below lithosphere
- 12. Bits of rock dropped from the air
- 15. Device used to measure earthquake waves
- 20. An ordered arrangement of rock layers bases on their ages
- 23. 146 Ma means 146 ______ years ago
- 25. Largest layer inside earth
- 26. Boundary formed when plates move away from each other, causing mid-ocean ridges
- 28. Vibrations caused by breaking rocks along faults
- 31. Area where two plates meet
- 32. Powerful sea wave that begins over an earthquake focus
- 33. Boundary formed when plates slide past each other
- 35. The point below Earth's surface in earthquake where energy release occurs
- 36. Number of plates on earth
- 37. Large pieces of rock in earth's outer shell
- 38. Large area of exposed Precambrian fossil
Down
- 1. Steep-walled depression around a volcano vent
- 2. Unit of geologic time into which an era is divided
- 6. Point directly above earthquake's focus
- 9. The study of magnetism inside rock's minerals
- 11. Soft, flexible upper layer of mantle
- 13. Who created the theory of plates
- 14. One super-continent when all landmasses were formed together
- 15. Scientist that studies earthquakes
- 16. Mid-Ocean ________ is an elevated portion of the ocean floor
- 17. One large ocean before continental drift
- 18. Boundary formed when plates move towards each other
- 19. Outside part of earth
- 21. Transfer of heat by movement of fluid
- 22. Middle part of earth
- 24. Geologic time is divided into 4 eons
- 27. Hawaiian Islands are _________________ in nature
- 29. A crack on Earth's crust
- 30. Location in mantle that melts rock into magma
- 34. One piece of evidence that proves the theory of continental drift