Across
- 4. Dissociation of molecules into ions
- 5. Include geological phenomena and processes that originate externally.
- 7. Eon where it’s anaerobic
- 8. Caused by the effects of changing temperature on rocks
- 11. Recognized the utility of fossils in subdividing geologic time
- 12. Plates sliding pass each other
- 15. One of the first to recognize the correspondence between rocks and time
- 16. Eon of visible life
- 19. plants and animals as agents of mechanical weathering
- 20. Divided the rock record into primary, secondary, tertiary, and quaternary
- 21. Associated with energy originating in the interior of the solid earth.
- 22. Wearing away of rocks by constant collision of loose particles
- 23. Alternate freezing and thawing.
- 24. Caused by rain water reacting with the rocks to form new minerals
Down
- 1. Age of reptiles
- 2. Change in the composition of minerals when they react with water
- 3. Plates moving away from each other
- 6. plates moving into each other
- 8. Formation of the protective ozone layer
- 9. Advanced the theory of seafloor spreading.
- 10. The breakdown of rocks at the Earth’s surface, by the action of rainwater
- 13. Observed that each layer contains a distinct assemblage of fossils
- 14. Chaotic time because of several meteorite bombardment
- 17. Age of mammals
- 18. Age of ancient life