Across
- 1. used by organisms for energy before oxygen
- 4. two minerals in banded iron formations
- 5. chemicals for life from meteorites
- 8. how deep did banded iron rocks form
- 13. middle layer of the earth
- 14. stromatolites are made of this bacteria
- 16. transfer of thermal energy thru fluid
- 17. age of stream deposits
- 18. organism that produced first oxygen
- 20. where banded iron formation rocks formed
- 21. happened to mars sized planet after collision
Down
- 2. caused earth to heat up to 2000 degrees
- 3. type of experiment that proved clumping
- 6. rocks that fall to earth from outer space
- 7. type of experiment to prove planet formation
- 9. type of force that caused clumping
- 10. surface of the earth
- 11. distance across a planet
- 12. area in Arizona where a meteorite fell
- 15. center of earth
- 19. a poison gas expelled from volcanoes