Named as uppermost of three formations of Pleasanton Group for hill north of Utica, southwest Livingston Co, MO. Type section is in shale pit of Midland Brick and Tile Company in NE1/4 SE1/4 sec 18, T57N, R24W, Livingston Co, Forest City basin. Outcrop extends from Bates Co northeastward to Adair and Putnam Cos, MO and into southern IA which includes Lincoln anticline and Iowa shelf. Divided into three members which are, in ascending order: Weldon River Sandstone Member (new) consisting of sandstone, shale, and a basal limestone conglomerate; Knobtown Limestone Member consisting of sandy limestone and fossiliferous calcareous sandstone; and Blue Mound Shale Member (new) consisting of a lower coal bed, Locust Creek coal bed (new), and an upper part of sandstone and shale. Thickness ranges from a few tens of ft in Kansas City area to over 100 ft where relief of basal unconformity is a maximum. Unconformably overlies Unity Farm Shale Member (new) of Lees Summit Formation (new) of Pleasanton. Disconformably underlies Critzer Limestone Member of Hertha Formation of Kansas City Group. Correlation chart. Measured sections. Fossil list. Lower member correlates with Trivoli Sandstone in western IL. Correlates with upper part of Tacket Formation in KS and lower part of Coffeyville Formation in northern OK. Late Pennsylvanian (Missourian) age.

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