Across
- 5. deeper layers are older
- 7. any feature that cuts through a sequence of rocks, it's younger
- 8. provides the exact age of a rock
- 9. modern era
Down
- 1. always younger than the surrounding rocks
- 2. hardened remains of an extinct species
- 3. first glaciers formed
- 4. Dinosaurs, intense climate
- 6. a fossil that's age is determined based off of the layer it's in
- 8. Earth forming, very chaotic