First published use of name in the Sierra Madre, Carbon Co, WY in the Northern Rocky Mountain region. Shown on several tables but no detailed description, discussion of source of name, nor designation of type included. Is one of 7 formations assigned to the Deep Lake Group assigned to the Early Proterozoic. Overlies Vagner Formation of Deep Lake Group. Underlies Slaughterhouse Formation, uppermost formation of Deep Lake. Consists of white, massive to mylonitized recrystallized quartzite (fig 2) or sandstone (fig 4). Thickness not stated. Of shallow marine origin.

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

An Early Proterozoic formation recognized in the Sierra Madre, Carbon Co, WY in the Northern Rocky Mountain region. Name changed from Copperton Quartzite to Copperton Formation because of presence of thick phyllite within it. Consists of a lower coarse-grained, highly sheared, kyanite-bearing quartzite, ferruginous phyllite (a few hundred meters thick) and an upper sheared quartzite. Copperton is at least 1,070 m thick. Considered similar in origin to the deltaic rocks of the Medicine Peak Quartzite, Lookout Schist, and Sugarloaf Quartzite of the lower part of the Libby Creek Group of the Medicine Bow Mountains.

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

An Early Proterozoic formation (one of six) assigned to Snowy Pass Group (defined) in Sierra Madre, Carbon Co, WY, Northern Rocky Mountain region. Is separated from the older Bottle Creek Formation (new) and from the younger Slaughterhouse Formation, both of the Snowy Pass Group, by thrust faults. Divisible into: a lower kyanitic quartzite (correlated with Medicine Peak Quartzite of Libby Creek Group of Snowy Pass Supergroup of Medicine Bow Mountains) that is 640 m thick, coarse grained and in sheared sections has ribbon quartz stringers; middle laminated phyllite (correlated with the Lookout Schist of Libby Creek Group of Snowy Pass Supergroup of Medicine Bow Mountains) that is about 285 m thick and has alternating quartz- and mica-rich layers; and upper orthoquartzitic quartzite (correlated with Sugarloaf Quartzite of Libby Creek Group of Snowy Pass Supergroup of Medicine Bow Mountains) that is white, massive and 145 m thick. Is about 1,070 m thick. Type section designated from SW1/4 sec 31 to S1/2 sec 29, T14N, R86W; this section is incomplete--lower and upper parts removed by major thrust faults. Named for village of Copperton. Geologic map; stratigraphic charts.

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