Across
- 4. branch of geology dealing wiith rock strata
- 7. name of an era when Pangaea existed
- 8. name of an era when flowering plants started to appear
- 10. type of fossil indicating certain time periods that species lived in
- 12. scientist who studies fossils
- 14. what was probably the last straw for the dinosaur extinction
Down
- 1. law stating older rock layers are on the bottom
- 2. preserved remains of organisms
- 3. end of what period did 82% of marine invertebrate go extinct
- 5. scientist who studies the Earth
- 6. how many large mass extinctions have happened on Earth
- 9. what the “m” stands for in m.y.
- 11. what uranium turns into as it decays
- 13. name of an era that humans are living in