Horseshoe Formation (ID)
(alphabetical) --all in ID: Blacksmith coal bed (informal), Boise coal bed (informal).
Late Cretaceous
Composite section (surface and subsurface): four sections in the Horseshoe Creek area, including a measured surface section on the ridge north of Horseshoe Creek, and 2 subsurface sections from the Philips Horseshoe No. 1 well and the Sunmark-Supron Miner Estate 4-34 well, Big Hole Mountains, T. 5 N., R. 44 E., Garns Mountain 7.5-min quadrangle, Teton Co., ID (Entzminger, 1979).
Idaho Mountains province
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