| Galena Group | |
| Type: | Group |
| Age: | Darriwilian-Sandbian |
| Period: | Ordovician |
| Country: | United States |
| Subunits: | Decorah Shale, Dunleith Formation, Wise Lake Formation, Dubuque Formation[1] |
| Underlies: | Maquoketa Group |
| Overlies: | Platteville Limestone |
| Extent: | Minnesota, Wisconsin and Illinois |
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]