Across
- 3. The preserved remains or traces of an ancient organism
- 4. A fossil of an organism that only lived for a short time period
- 6. A fossil that displays the behavior of an organism such as footprints
- 7. A piece of an older rock becomes part of a newer rock
- 10. Theory that states that changes to Earth are a slow and gradual process
- 13. Two or more forms of an element found in a rock or fossil
- 14. The time it takes for half of an isotope to decay
Down
- 1. Matching rocks and fossils from separate locations
- 2. Theory that states that Earth was shaped by natural disasters such as volcano eruptions and floods
- 5. A principle that states that younger rocks lie above older rocks
- 8. A gap in the geologic record created when a rock layer is eroded and missing
- 9. The age of a rock compared to other rock layers
- 11. The spontaneous decay of an isotope found inside a rock or fossil
- 12. The age of a rock in years