Name McMicken introduced for highly calcareous and extremely fossiliferous shales and limestones composing upper third of Eden formation. Thickness 60 ft. Contains abundant bryozoan DEKAYELL ULRICHI. Age is Late Ordovician. [Wilmarth (1938, US geologic names lexicon, USGS Bull. 896) states that unit is currently treated as upper member of Latonia shale of Eden group (reference(s) not given).]
Source: GNU records (USGS DDS-6; Reston GNULEX).
Pl. 1. McMicken formation of Eden group. Shown on generalized stratigraphic column of Ordovician and Silurian rocks exposed in Jefferson and Switzerland Counties, [eastern] Indiana (J.J. Galloway, J.B. Patton, and T.G. Perry, compilers, April 1953). Consists of blue- or greenish-gray, soft shale and drab-gray, irregularly bedded, impure limestone. Thickness 60 to 80 feet. Is top formation of Eden group; overlies Southgate formation. Underlies Mount Hope formation of Maysville group. Fossils [listed]. Age is Late Ordovician (Cincinnatian).
Source: Publication; US geologic names lexicon (USGS Bull. 1200, p. 2309).
Stratigraphic column illustrates continued usage of McMicken Member of Latonia Formation. Overlies Southgate Member of Latonia and underlies Mount Hope Member of Fairview Formation. Age is Late Ordovician (Cincinnatian).
Source: GNU records (USGS DDS-6; Reston GNULEX).
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