Study guide on Archean

1. Know the duration of Precambrian, and Archean (also in term of 24 hours) Why is the only possibility for timing is the absolute age?

2. What pregeologic history means? Know the different kind of meteorites, how the asteroid zone formed, and when? How old is the oldest crustal rock?

3. How did the differentiation of the earth happen?

4. What could be the composition of the earliest crust? Understand how granitic crust evolved by partial melting?

5. What are the meaning of the following terms: Shield, platform, craton. Be able to explain each of them. (Best way, to practice with girl/boyfriend around midnight, to keep your partner excited). The area of Canadian shield.

6. Typical Archean rocks: Greenstone, gneiss. You must know which is which, how did they form, what is their composition?

7. Kenoran orogenesis. What is the importance of this orogen? How about the plate tectonics in the Archean?

8. Evoluion of atmosphere! Know the formation, does the earth have its original atmosphere? Why or why not? How the atmosphere formed, what was its composition, how is it different or similar to the present day one?