Orosirian Period

Extensive mountain building

The Orosirian is the third period of the Paleoproterozoic Era, occurring after Rhyacian, and before the Statherian.

Geologic Age

Eon / Era

What happened during this time?

Geological

Vredefort Crater

Sudbury Crater

Above: Continent placement during the Orosirian Period

Below: Figure 1 from Allen et al. 2022 showing the Vredefort crater

Biological

Gunflint Biota

Grypania spiralis

Above: An early eukaryotic algae, Grypania

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