Named as upper formation, of five formations, of Libby Creek Group. Is well exposed in area of Slaughterhouse Gulch north of the Encampment River, Carbon Co, WY in the Northern Rocky Mountain region. No type locality designated. The marble consists of fine- to medium-grained calcite, interlayered calcite, dolomite, and quartz. Includes interbedded chlorite-calcite and biotite-calcite schists with accessory hornblende, magnetite, and pyrite. Probably 300 m thick. Conformably overlies Quartzite Peak Quartzite (new) of the Libby Creek Group. Has an irregular top bounded by low angle faults. Geologic map; mapped with other formations of Libby Creek Group. Assigned to the Proterozoic. Columnar section.

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

Name changed from Slaughterhouse Marble to Slaughterhouse Formation, and assigned as the upper formation of the Deep Lake Group on figure 1 and as the lower formation of the Libby Creek Group unconformably above the Deep Lake on figure 4. Used in the Sierra Madre, Carbon Co, WY in the Northern Rocky Mountain region. Unconformably overlies Copperton Quartzite of Deep Lake Group. Composed of thick calc-silicate and calcareous phyllite, and buff to tan, arenaceous, silica-seamed metadolomite. Is of carbonate bank origin. Correlated with upper part of Rock Knoll Formation in the Medicine Bow Mountains. Correlation chart. Early Proterozoic age.

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

Name applied to the upper formation in the upper part of the Snowy Pass Group (defined) in the Sierra Madre of Carbon Co, WY in the Northern Rocky Mountain region. Type locality designated in sec 26 and W1/2 sec 25, T14N, R86W; section is incomplete; is about 500 m thick. Correlated with the Nash Fork Formation of Libby Creek Group of Snowy Pass Supergroup in Medicine Bow Mountains. Nash Fork may have been deposited on a carbonate platform whereas Slaughterhouse deposited on basin slope of platform. Is separated from the older Copperton Formation of the middle part of the Snowy Pass by a thrust fault. Placement within the sequence remains uncertain. Upper contact may be a thrust fault. Basal part consists of fine-grained yellow, red, and green metalimestone that has layers of buff metadolomite, quartzite, and dark-green phyllite. Basal part grades upward (in sequence) into dark-gray graphitic phyllite, and fine-grained chlorite, calc-schist. Of Early Proterozoic age. Geologic map; stratigraphic charts.

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