Across
- 7. States the in an undisturbed sequence of rocks the oldest are at the bottom
- 9. the comparison of younger rocks to older rocks.
- 10. States that any rock or fragments that is included inside another rock mens that the fragments are older than the bigger rock.
Down
- 1. Assigning actual dates to rocks, from looking at decay.
- 2. Any feature that cuts across a feature of rocks is younger than what they cut through.
- 3. the eon where earth formed its magnetic field to protect us from UV rays.
- 4. in this eon the first animals and plants appeared. The first creatures were like lizards.
- 5. How long it takes for a material to return to half the radiation it usually is.
- 6. The remains of animals that lived long ago
- 8. a fossil that is useful for dating and correlating the strata in which it is found.