Across
- 8. Fossilized dung
- 9. Holes made by animals in sediment
- 10. Preserved remains or traces of ancient life
- 11. Hollow imprint of an organism
- 13. Age compared to other rocks or fossils
- 14. Organism turns to stone
- 19. Layered structures made by cyanobacteria
- 20. Evidence of an organism’s activity (like footprints)
- 21. Older rocks lie beneath younger rocks
Down
- 1. Fossil formed when minerals fill tissues
- 2. Timeline of Earth’s history
- 3. Exact age in years
- 4. Original material of an organism is replaced by minerals
- 5. Fossil retains only carbon residue
- 6. History of life preserved in fossils
- 7. Hardened tree sap that can trap organisms
- 12. Rocks formed from compacted sediments
- 15. Extinct marine mollusks with coiled shells
- 16. Fossil used to date rock layers
- 17. Scientist who studies fossils
- 18. 3D copy of an organism formed in sediment