Across
- 2. wiped out by meteor.
- 4. rocks are mostly made of this
- 5. changes by different forms of pressure and friction
- 7. a type of energy output
- 9. disappearance of 96% of marine species and 75% of land species.
- 13. death of 70% of marine species
- 14. generates lots of ash
- 18. name for a kind of grouping of organisms
- 20. someone who studies fossils
- 22. preserved remains
- 23. identification of a time period
Down
- 1. layers of minerals
- 3. make up our skeleton
- 6. appearance of dinosaurs
- 8. layers stacked on eachother
- 10. this is what pushes the layers together
- 11. the reason we survive on earth (takes a long time)
- 12. this happend to the dinosaurs
- 15. appearance of plants
- 16. the change from bone to mineral
- 17. the ending of an organism
- 19. heats the earths surface to this day
- 21. death of 50% of animal species