When did Lake Superior-type banded iron formations form?

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mineral deposit The relationship between hot springs and epithermal veins.

Lake Superior-type banded iron formations (BIFs) formed during a specific metallogenic epoch between 2.7 and 1.8 billion years ago.12

This narrow time frame suggests that the Earth's atmosphere and oceans possessed a unique chemical composition during this period that allowed for the transport and precipitation of iron, a process that is not possible in today's oxidizing environment. These deposits, which are found in shallow waters of continental shelves or ancient sedimentary basins, are characterized by their significant lateral continuity and are mined globally, including in the Lake Superior region, the Hamersley Basin of Australia, and the Labrador Trough in Canada.12