Across
- 1. the rule that a fault or intrusion is younger than the rock it cuts through
- 4. an opening in Earth’s crust where magma, ash, and gases can escape
- 6. the process in which new ocean crust forms at a mid-ocean ridge
- 8. the layers of rock, fossils, and other evidence that show Earth’s history
- 11. melted rock beneath Earth’s surface
- 15. a place where magma rises through a plate and can form volcanoes away from boundaries
- 20. a valley formed when land pulls apart at a divergent boundary
- 21. a large ocean wave caused by undersea plate movement or earthquakes
- 22. a sudden shaking of Earth caused by movement of tectonic plates or faults
- 27. the shape and elevation features of Earth’s surface
- 28. the age of a rock or fossil compared with another, not the exact age
- 31. a plate boundary where two plates move apart
- 34. a geologic process that wears away or breaks down Earth’s surface
- 35. a plate boundary where two plates slide past each other
- 37. a fossil used to match rock layers because it is widespread but found in only one time period
- 38. a break in Earth’s crust where movement has occurred
- 39. the circular movement of heated material that helps move tectonic plates
- 40. Earth’s thin outer solid layer
- 41. a deep valley in the ocean floor usually formed at a convergent boundary
- 42. the rigid outer layer made of the crust and uppermost mantle
- 43. the liquid layer of Earth that surrounds the inner core
Down
- 2. the rule that in undisturbed rock layers, the oldest layer is on the bottom
- 3. preserved remains or evidence of an organism from the past
- 5. the process in which denser materials sink and lighter materials rise, forming layers
- 7. a wave of energy that travels through Earth and helps scientists study Earth’s interior
- 9. the idea that geologic processes happening now also happened in the past
- 10. the idea that continents were once joined and slowly moved apart over time
- 12. the breakdown of rock into smaller pieces at Earth’s surface
- 13. the process in which sediment is dropped and builds up in a new place
- 14. how much mass is packed into a certain amount of space
- 16. the soft, flowing layer of the upper mantle where convection currents move
- 17. a large moving mass of ice that shapes Earth’s surface
- 18. magnetic evidence in rocks that supports seafloor spreading and plate tectonics
- 19. the actual age of a rock or fossil, often determined by radiometric dating
- 23. the thick middle layer of Earth between the crust and core
- 24. a depositional landform formed where a river slows and drops sediment
- 25. a plate boundary where two plates move toward each other
- 26. the center layer of Earth made of the outer core and inner core
- 29. a geologic process that builds up Earth’s surface, such as deposition
- 30. the movement of weathered rock and sediment from one place to another
- 32. the solid innermost layer of Earth
- 33. the theory that Earth’s lithosphere is broken into plates that move
- 36. an underwater mountain chain formed at a divergent boundary