Sentences with phrase «ancient oceans oxidized»

Oxygen present in ancient oceans oxidized dissolved iron, which precipitated out of solution onto the ocean floors.

Not exact matches

This research not only provides the first clear evidence that microorganisms were directly involved in the deposition of Earth's oldest iron formations; it also indicates that large populations of oxygen - producing cyanobacteria were at work in the shallow areas of the ancient oceans, while deeper water still reached by the light (the photic zone) tended to be populated by anoxyenic or micro-aerophilic iron - oxidizing bacteria which formed the iron deposits.