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