St. Marks Formation


The St. Marks Formation is a Miocene geologic formation in the eastern Florida Panhandle.

Age

Period: Neogene
Epoch: Miocene ~23.03 to 5.33 mya, calculates to a period of
Faunal stage: Arikareean through Hemphillian

Location

The St. Marks Formation is exposed in Wakulla [County, Florida|Wakulla], southern Leon and southern Jefferson County, Florida on the northwestern flank of the Ocala Platform and along with Suwannee Limestone and Ocala Limestone makes up the upper part of the Floridan Aquifer in the eastern panhandle.

Composition

The St. Marks Formation consists of a white to yellowish gray, poorly to moderately hard, sandy, fossil bearing rock in molds and casts within packstone to wackestone.

Fossils

The fossils are in molds and casts and include: