Across
- 3. The time it takes for half of the specimen to decay.
- 7. mesozoic
- 8. All fragments are older than the rock that they are included in.
- 9. Sections of an eon
- 10. cutting across sediments.
Down
- 1. an estimate of age.
- 2. the oldest layer on bottom
- 4. An old organizam
- 5. The age in years
- 6. a tool used for relative dating