Girkin Formation

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:

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