Results for: Proterozoic

What do Proterozoic-aged red beds and banded iron formations tell us about the Earth's early atmosphere?

Banded iron formations indicate that there were oxygen-rich and oxygen-poor episodes during Earth's early atmosphere. Banded iron formations first appear in the Archean, 3 bil (MORE)

Did oxygen exist in the atmosphere during the Proterozoic?

Certain minerals oxidize, or rust, in the presence of free oxygen. Proterozoic red beds are sedimentary rocks deposits that contain oxidized iron. They are the evidence that t (MORE)