Across
- 3. and assumption of a rocks age
- 6. shows the events of earth's history
- 8. give the exact year of a rocks age
- 10. sequence of sedimentary rock layers
Down
- 1. product decay turn into daughter products
- 2. radioactive decay of in isotopes
- 4. subdivision of geologic time
- 5. useful for dating strata that is found
- 7. rocks found inside other rocks are older than the other two
- 9. long period of time