Pg. 58, 59 (fig. 5), 60 (fig. 6), 62. Bear Gulch limestone lentil of Tyler formation; Bear Gulch limestone member of Tyler formation. Overlain by Amsden sandstone. Removal of soluble beds (Heath gypsum) beneath this unit has caused a remarkable series of solution slump blocks in this area worthy of special study. [Age is Mississippian.]
Named from exposures in Bear Gulch [Bear Creek, in T. 14 N., R. 21 E.], Fergus Co., central MT; composite section in secs. 32 and 33, T. 14 N., R. 21 E., south of Forestgrove.
[Called Bear Creek on USGS Forestgrove 7.5-min quadrangle (Maughan, 1984).]

Source: Publication; US geologic names lexicon (USGS Bull. 1200, p. 250).

Pg. 1942 (fig. 2), 1953, 1954. Bear Gulch tongue of Cameron Creek member of Tyler formation. Bear Gulch referred to as tongue in Cameron Creek member. Consists of medium-bedded black dense limestone with a marine fauna. Age is Early Pennsylvanian (Morrow).

Source: Publication; US geologic names lexicon (USGS Bull. 1200, p. 250).

Pg. 180 (fig. 2), 183 (fig. 4), 185, 187. Bear Gulch Member of Tyler Formation of Amsden Group adopted by the USGS. Chiefly medium-gray to dark-gray, laminated to thin-bedded argillaceous limestone and very calcareous mudstone. Thickness up to 210 feet (subsurface). Intertongues with Stonehouse Canyon Member of Tyler; Maughan and Roberts (1967) included these rocks in Stonehouse Canyon at Potter Creek dome where it is a thin limestone bed about 160 feet (50 m) above base of Tyler. Fossiliferous. Age is Early Pennsylvanian (Morrowan).
Type locality: along Bear Creek, in sec. 21, T. 14 N., R. 21 E., [approx. Lat. 46 deg. 57 min. 15 sec. N., Long. 109 deg. 03 min. 30 sec. W.], Forestgrove 7.5-min quadrangle, Fergus Co., central MT.

Source: Publication.