Name derived from Headquarters Park, T16N, R80W, Carbon Co, WY, Northern Rocky Mountain region. No type locality designated. Consists of greenish-gray chloritic phyllite or schist with several beds of metaquartzite, glacial metaconglomerate, metadolomite, and schistose basic pyroclastics. Section near Twin Lakes 2,770 ft thick described. Is younger than Deep Lake metaquartzite (new); the contact is a probable unconformity. Is older than Heart metagraywacke (new); the contact is conformable. Is of pre-Cambrian age, probably early Algonkian or Proterozoic. Glacial origin suggested--the pebbles thought to be a tillite; some of the silts are varved (banded beds 1-5 mm in regular widths).

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

Revised in that Headquarters Formation is assigned (1 of 6 formations) to the lower part of the Libby Creek Group of the Snowy Pass Supergroup (first used) in the Medicine Bow Mountains of south-central WY in the Northern Rocky Mountain region. Divided into lower member of lenticular paraconglomerate, quartzite, and schist 350 m thick, and an upper member of laminated schists and phyllites 300 m thick. In the lower member, the paraconglomerates have granite, quartzite, and schist clasts (avg 4-6 cm but can be 1 m in diameter) in poorly sorted matrix of sand- and silt-sized quartz, plagioclase, K-feldspar, rock fragments, and micas, and occur as lenses. The quartzites are plagioclase-rich arkoses. In the upper member, a biotite, chlorite, quartz phyllite is laminated by quartz-rich and mica-rich layers. Sedimentary structures include small-scale planar and trough cross beds, laminations, climbing ripples. Considered to be a prodelta and delta-front deposit of Proterozoic age. Geologic map; stratigraphic chart.

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

Lower contact revised in the Medicine Bow Mountains, Albany and Carbon Cos, WY in the Northern Rocky Mountain region in that the Headquarters Formation of Libby Creek Group unconformably overlies the newly named Rock Knoll Formation of the Deep Lake Group (raised in rank from Deep Lake Metaquartzite). The Headquarters is divided into: a lower member, 1,120 ft thick, probably deposited in a glacio-marine environment; and an upper member, 980 ft thick, deposited either in a large lake or in a marine environment. Overlying parts of Libby Creek not described. Headquarters mapped in central Medicine Bow Mountains. Libby Creek is of Early Proterozoic age. Geologic map; stratigraphic charts.

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

Assigned in the Medicine Bow Mountains, Carbon and Albany Cos, WY, Northern Rocky Mountain region, as one of six formations of the lower part of the Libby Creek Group of the newly defined Snowy Pass Supergroup. Unconformably overlies Rock Knoll Formation, formerly assigned to Deep Lake Group but reassigned to lower part of Libby Creek. Underlies Heart Formation of lower part of Libby Creek. Divided into a lower diamictite member 350 m thick and an upper phyllite member 300 m thick. Correlated with part of Bottle Creek Formation (new) of Snowy Pass Group of Sierra Madre. Correlation chart. Geologic map; mapped as an undivided unit. Of Early Proterozoic age.

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