Pg. 526. Nebraska City ledge. Ledge of limestone and sandstone that weather into irregular slabs with a rough granular surface. Not named in Condra and Bendston's [1915] Nebraska report. I suggest name Nebraska City ledge for this double ledge. Upper 2 feet is dark-bluish limestone of fine texture along some layers and along other seams almost wholly made up of very small and thin shell fragments, lying flat; this is underlain by 1 foot of shaly silt; followed below by 0.75 foot of dark-gray limestone, in places brownish; basal 2.5 feet is arenaceous and calcareous rock of fine texture and bluish color, consisting of a siliceous, well-assorted silt or sand embedded in calcareous material. This ledge is not a constant horizon. In passing south it grades into sandstone and cannot be recognized a few miles south of State line in Missouri.
Type section: upper strata in brickyard shale pit, 0.25 mi south of Missouri River bridge at Nebraska City, Otoe Co., southeastern NE.

Source: US geologic names lexicon (USGS Bull. 896, p. 1470-1471).

Pg. 116. Nebraska City limestone in Pony Creek shale bed of McKissick Grove shale member of Wabaunsee formation. Dark bluish-gray massive, hard, somewhat sandy and pebbly, in large rectangular blocks, weathering buff to brownish and slabby, 2 feet 10 inches thick in bluff and clay pits southeast of Nebraska City. Fossils. Top bed of Pony Creek shale, which is top unit of McKissick Grove shale.

Source: US geologic names lexicon (USGS Bull. 896, p. 1470-1471); GNC KS-NE Pennsylvanian Corr. Chart, sheet 1, Oct. 1936; supplemental information from GNU records (USGS DDS-6; Denver GNULEX).

Nebraska City limestone member of McKissick Grove shale underlies Pony Creek shale and overlies Frenck [French] shale (redefined).

Source: US geologic names lexicon (USGS Bull. 896, p. 1470-1471); GNC KS-NE Pennsylvanian Corr. Chart, sheet 2, Oct. 1936.

Pg. 9-10. Nebraska City limestone member of Pony Creek shale formation. Changed last definition [Moore and Condra, Oct. 1932 Kansas and Nebraska revised classification chart]. Thickness 2+/- feet. Overlies French Creek shale member; underlies Caneyville shale member. Age is Late Pennsylvanian (Virgil).
See "Modern classifications of the Pennsylvanian rocks of eastern Kansas and southeastern Nebraska," compiled by M.G. Wilmarth, Secretary of Committee on Geologic Names, USGS unpub. corr. chart, Oct. 1936, sheet 2.

Source: US geologic names lexicon (USGS Bull. 896, p. 1470-1471, Jim Creek entry p. 1046); GNC KS-NE Pennsylvanian Corr. Chart, sheet 2, Oct. 1936.

Pg. 2274 (fig. 1), 2275. Nebraska City limestone member of Wood Siding formation. Basal unit of Wood Siding formation. Underlies Plumb shale member (new); overlies French Creek shale member of Root shale (new). Age is Late Pennsylvanian (Virgilian).

Source: US geologic names lexicon (USGS Bull. 1200, p. 2697-2698).