Pg. 356-368. Beloit formation. Name proposed for the beds beneath Galena limestone, which in previous reports have been called Trenton limestone but which are now considered to probably be older than Trenton limestone of New York; the Galena probably being = New York Trenton. The Beloit includes beds which in previous reports have been called Blue limestone and Buff limestone. Age is Middle Ordovician.
[Named from exposures at Beloit, Rock Co., eastern WI. Extends into subsurface of northeastern IL.]
[GNC remark (ca. 1936, US geologic names lexicon, USGS Bull. 896, p. 157): The Beloit dolomite overlies St. Peter sandstone, and includes equivalents of Decorah shale (of Trenton age) and Platteville limestone (of Black River age).]

Source: US geologic names lexicon (USGS Bull. 896, p. 157).

Pg. 262-264. Beloit dolomite. In eastern part of zinc-lead mining district and farther east, strata of Platteville, Decorah, and Galena age are dolomite, and gross lithology of the three formations is somewhat similar. This eastern area is the type for Sardeson's (1896) Beloit formation. However since term Beloit has been virtually forgotten and terms Platteville and Decorah have been used consistently since 1906, they are retained in this report.

Source: US geologic names lexicon (USGS Bull. 1200, p. 294).