Named as part of Late Pennsylvanian (Missourian and Virgilian?) South Bend Limestone Member of Stanton Formation (both revised). Named for Gretna Fish Hatchery (now Schramm Park) where exposed in NE1/4SW1/4 sec 12, T12N, R10E, Springfield quad, Sarpy Co, lower Platte River valley, southeastern NE. Traceable throughout outcrop areas and in subsurface, the Gretna is identified in southeastern KS as well. Measured section at type reveals shale to shaly limestone, light gray-brown, light green, and contains conodonts. Also described as a transgressive facies, an offshore shale, dark gray-brown and silty to clayey (figs. 2, 4, 21, appendix). Thickness at type is about 0.5 ft (0.15 m). Conformably overlies Late Pennsylvanian (Missourian and Virgilian?) Little Kaw Limestone bed (revised) in South Bend Limestone Member. Conformably underlies Late Pennsylvanian (Virgilian?) Kitaki Limestone bed (new) of the South Bend. Age is Late Pennsylvanian (Virgilian?) probably based on fossils. Report includes measured sections and correlation charts.

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