Galena Group
From Wikipedia, the free encyclopedia
From Wikipedia, the free encyclopedia
The Galena Group or Galena Limestone refers to a sedimentary sequence of Ordovician limestone that was deposited atop the Decorah Shale. It is part of the Ordovician stratigraphy of the Upper Midwestern United States. It was deposited in a calm marine environment, and is fossiliferous.[2]
Galena Group | |
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Stratigraphic range: Darriwilian-Sandbian | |
![]() Unidentified Trochonema from the Galena Group | |
Type | Group |
Sub-units | Decorah Shale, Dunleith Formation, Wise Lake Formation, Dubuque Formation[1] |
Underlies | Maquoketa Group |
Overlies | Platteville Limestone |
Location | |
Country | United States |
Extent | Minnesota, Wisconsin and Illinois |