The Girkin Formation is a geologic formation located in the Chester Escarpment of central Kentucky, USA. It comprises a level of Mammoth Cave and lies above the Ste. Genevieve Limestone and St. Louis Limestone and below the Big Clifty Sandstone in that area. The Girkin is a limestone Mississippian in age.
Members of the Girkin are as follows in descending order:
References
Girkin Formation Wikipedia(Text) CC BY-SA