[1][2] Its marine fossils notably include Michigan's state stone, the Petoskey stone (the extinct coral Hexagonaria percarinata), among other corals and records of ancient marine life.

[3] The Traverse Group outcrops in Emmet and Charlevoix counties along the northwestern shore of Michigan's lower peninsula.

Its formations are Gravel Point, Charlevoix Limestone, Petoskey, and Whiskey Creek.

[4] The Gravel Point Formation consists of a lithographic gray to brown limestone with shale beds up to 0.5 meters thick; it also includes chert nodules and bioherms (fossilized reef mounds).

The Traverse Group formed as a shallow carbonate shelf during the Devonian period (~419 to 359 Ma), when the most recent supercontinent, Pangea, was just beginning to take shape.