Named as a member of Haystack Mountains Formation (new) of Mesaverde Group (new rank) for Tapers Ranch in S1/2 min. quad, Carbon Co., WY. Type section selected and measured in NE1/4 NE1/4 sec 22, NE1/4 sec 23 and SE1/4 SE1/4 sec 14, T22N, R86W, Carbon Co., in Green River basin. Composed mostly of sandstone and is 275 ft thick at type. Sandstone beds may be yellowish-or greenish-gray to dark-gray; some are glauconitic, calcareous, thin bedded, cross bedded, and range from coarse grained to very fine grained. Rests conformably on Steele Shale at type. Underlies lower unnamed member of Haystack Mountains. Assigned to the early Campanian of the Late Cretaceous. Probably originated in a marine environment of probably deeper water than either the Hatfield or O'Brien Spring Members. Correlation with other Cretaceous units in south-central WY shown on Table 1.

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