quote:
Yes, there is evidence.
http://volcano.und.nodak.edu/vwdocs/Gases/origin.html
"Perhaps the best geologic evidence for the composition of the early atmosphere is the presence and abundance of Banded Iron Formations. These rocks are made of layers of sulfide minerals (evidence for a reducing environment) and chert or fine-grained quartz. These rocks are not present in rocks younger than 1.8 - 2.5 billions of years ago, when oxygen starting becoming more abundant."
Not that I disagree about the then state of the atmosphere, but I think arguement may be flawed. Perhaps I am wrong, but I believe that the Banded Iron Formation (BIF) deposited at that 1.8-2.5 bya time boundry was deposited as carbonates, sulfides, and oxides. The oxide deposition
may very well be the result of a more oxygenic atmosphere - The oxides being deposited in a shallower, more oxygenic sea, and the sulfide being deposited in a deeper, more reducing environment.
Regardless, this BIF timeline marks some sort of significant environmental change.
Moose
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Old Earth evolution - Yes
Godly creation - Maybe
Edit note: Deleted #17, which was a duplicate of #16
[This message has been edited by minnemooseus, 01-09-2002]
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