Applied Brereton limestone to basal beds of McLeansboro formation of Fulton County, central western Illinois, and called overlying beds Copperas Creek shale and sandstone. Age is Pennsylvanian. Thickness and origin of name not stated, but probably named from the town in Fulton County.

Source: US geologic names lexicon (USGS Bull. 896, p. 259).

Chart no. 6 (column 25, Indiana, collated by H.R. Wanless and J.M. Weller). Brereton limestone [unranked]. Shown on Pennsylvanian correlation chart as limestone in Petersburg formation in Indiana. The Brereton is basal limestone of McLeansboro formation in central, western, and northern Illinois (columns 28-30, collated by H.R. Wanless and J.M. Weller). Age is [Middle Pennsylvanian]; Desmoinesian; Westphalian D.
[Shown on chart correlative with Providence limestone (unranked) in Carbondale formation in western Kentucky (col. 26), and with Herrin limestone (unranked) at base of McLeansboro formation in southern Illinois (col. 27).]

Source: Publication; US geologic names lexicon (USGS Bull. 1200, p. 468-469).

Pg. 50 (fig. 22), 107, 111-112, 195 (geol. sec. 16). Brereton limestone. Included in Brereton cyclothem, [Carbondale] group. Overlain and underlain by unnamed shale units. Stratigraphically below Sheffield shale (new). Age is Pennsylvanian.
Type locality: east bank of Middle Copperas Creek, in SE/4 NE/4 sec. 1, T. 7 N., R. 4 E., Glasford 15-min quadrangle, Fulton Co., central western IL. Named from nearby town of Brereton, Fulton Co., central western IL.

Source: US geologic names lexicon (USGS Bull. 1200, 468-469).

Pg. 34, 35, 48 (table 1), 65, pl. 1. Brereton limestone member of Carbondale formation of Kewanee group (new). Carbondale redefined as formation and includes Brereton limestone member. Name Brereton is extended to caprock of No. 6 coal in southern Illinois to replace name Herrin, now restricted to Herrin (No. 6) coal member. Underlies Jamestown coal member in southern Illinois and Lawson shale member (new) in western and northern Illinois. Thickness 3.5 feet. Age is Pennsylvanian. Report presents new rock-stratigraphic classification of Pennsylvanian strata in Illinois. Cyclical classification retained but is entirely independent of rock-stratigraphic classification.
Type locality: east bank of Middle Copperas Creek, in SE/4 NE/4 sec. 1, T. 7 N., R. 4 E., Glasford 15-min quadrangle, Fulton Co., west-central IL. Named from town of Brereton, IL (Wanless, 1957).

Source: Publication; US geologic names lexicon (USGS Bull. 1200, 468-469).