Stonington Formation

Stonington Formation Stratigraphic range: Late Ordovician
Type	Formation
Unit of	Richmond Group
Sub-units	Ogontz Member and Bay de Noc Member
Underlies	Big Hill Formation
Overlies	Bill's Creek Shale
Location
Region	Michigan
Country	United States

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