G103/203                                                                      Objective Chapter 19 Precambrian Earth

 

1)  What is the solar nebular hypothesis

 

2)  What are the three divisions of the Precambrian eon and what times do each encompass?

 

3)  Be able to discuss what the earth was believed to be like during the earliest stages of it’s existence and cite evidence used to indicate when the atmosphere had “free” oxygen and when the first crustal rocks were formed.

 

4)  Why are Zircons so great for determining the age of crustal development?

 

5)  What is believed to be the composition of the early crust on earth like and what was plate tectonics believe to be like on the early earth?

 

6)  Explain the idea of partial melting and how this process eventually created oceanic and continental crust on earth.

 

7)  What are the components of a continent and a craton?

 

8)  Where is the oldest crust on earth found and what is it?

 

9)  What type of rocks are found that date to the Archean?’

 

10)  What makes up greenstone belts and why are they called this?

 

11)  Approximately when did an atmosphere develop on earth, where did it come from, and what is believed to be the general composition of the early atmosphere?

 

12)  What is believed to be the source of oceans on earth and about when did they develop

 

13)  Explain the two processes that puts oxygen into the atmosphere.

 

14)  What is a stromatolite and how are they important in the development of oxygen in the earth’s atmosphere?

 

15)  Explain the difference between a heterotrophic and an autotrophic organism

 

16)  What does anaerobic mean?

 

17)  What is the difference between prokaryotic cells and eukaryotic cells and which came first?

 

18)  How is the continents different in the Proterozoic and the Archean?

 

19)  What is the Grenville orogeny?

 

20)  How many supercontinents existed in the Proterozoic and what were their names?

 

21)  What are the banded Iron Formations and red beds and what do the represent?  How are they economically important today?

 

22)  What is the Ediacarian Fauna, what are the characteristics of these organisms and when did they exist?