Geologic Time Scale
Across
- 4. Used for Absolute Dating
- 7. In an undisturbed sequence of rocks, the oldest rocks are on the bottom and the youngest rocks are on the top
- 9. Layers
- 10. Comparing ages to determine order of Earth Events
Down
- 1. Any feature that cuts across a sequence of rocks, is younger than everything it cut
- 2. Amount of time it takes for half an isotope to decay to a daughter product
- 3. Any rock or fragment that’s included inside of another rock is older than the rock in which it is included
- 5. Lived 251-65 million years ago
- 6. Believed to be the first life form on Earth
- 8. Finding the exact age of something