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Nachusa Formation
Stratigraphic range: Ordovician
Type	Formation
Location
Region	Illinois
Country	United States

The Nachusa Formation is a geologic formation in Illinois. It preserves fossils dating back to the Ordovician period.

• List of fossiliferous stratigraphic units in Illinois

• Various Contributors to the Paleobiology Database. "Fossilworks: Gateway to the Paleobiology Database". Retrieved 17 December 2021.

This article about a specific stratigraphic formation in Illinois is a stub. You can help Wikipedia by expanding it.

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