Geological Time Review

2. The study of rock strata
4. Produces geological structures such as folds, joints, faults
8. Cenozoic Era is also known as the age of the ______
9. This Eon is divided into 3 eras
10. This era is divided into the Tertiary and Quaternary periods
11. Ancient cores of the continents
13. When rock layers are located in different places, they are matched up by _________
15. A gap between rocks of very different ages, often marked by an erosional surface
17. Earth's history is recorded on the _____Time Scale
19. The comparison of one rock or fossil to another to determine which one is older or younger is called ______age.
21. This era is divided into the Triassic, Jurassic, and Cretaceous periods

1. The lowest layers are the oldest and the higher layers are the youngest
3. Cyanobacteria, responsible for adding oxygen to the atmosphere
5. The earliest crust was probably made from this
6. One of the eras in the Phanerozoic eon
7. One of the eras in the Phanerozoic eon
11. This is the era we live in now
12. Common index fossils
14. This mass extinction occurred 65 mya in the Mesozoic Era
16. Longest portions of geological time
18. _____ beds is an example of the iridium layer that was deposited at the time of the Cretaceous-Tertiary extinctions
20. This type of fossil must be distinctive, widespread, and short-lived