Across
- 3. and their decay products
- 5. Dating any method of measuring the age of an object or event in
- 7. and pressure
- 8. a type of rock that forms from the cooling of molten rock
- 11. fossils a fossil known to have lived in a particular geologic age
- 12. dating the process of measuring the absolute age of geologic
- 13. or younger than other events or objects
- 14. a crack in the Earth's crust
- 15. by measuring the concentrations of radioactive
- 17. by geologists and paleontologists
Down
- 1. or ice sheets
- 2. Rocks that undergo a physical change due to extreme
- 4. can be used to date the rock layer in which it is found
- 6. Time Scale the categories of time into which Earth's history is usually
- 9. study of earth history
- 10. or below the surface
- 12. dating any method of determining whether an event or object is
- 16. core A long cylinder of ice obtained from drilling through ice