Reassigned as the upper (of 3 members) member of Pinicon Ridge Formation (new) of Wapsipinicon Group (rank raised). Overlies Spring Grove Member, newly assigned to Pinicon Ridge Formation. Consists mostly of dense limestone, dolomitic limestone, and dolomite. The limestones are partly laminated, pelletal, oolitic, intraclastic, and have birdseye fabric. Usually unfossiliferous. Some ostracodes, burrows, and stromatolites. Scattered shale partings and lenses. Extensively brecciated. Breccias have angular clasts and blocks of carbonate in a matrix of limestone or dolomite. Is evaporite dominated in parts of northern IA. Breccias interpreted to have formed by evaporite solution collapse during open marine deposition of overlying Cedar Valley Group. Some clasts were derived from overlying Solon Member of Little Cedar Formation (new) of Cedar Valley Group (rank raised). Nomenclature charts. Graphic sections. Ranges between 6 to 10 m in northeastern IA and as much as 31 m in southern IA on the Iowa shelf. Of Middle Devonian, Givetian age.

Source: GNU records (USGS DDS-6; Denver GNULEX).