Name applied to sequence on west knob of Leonard Mountain about 1 mi west-northwest of Benchmark 5860, Hess Canyon and Altuda 15 min quads, Brewster Co, TX in the Permian basin. These exposures measured and designated the type section. Overlies Lenox Hills Formation. Underlies Cathedral Mountain Formation. Is 509 ft thick at its type where it consists of (ascending): biohermal limestone; coarsely granular massive, conglomeratic limestone; thick-bedded limestone and yellow sandy shale; biohermal limestone and calcarenite with pink-brown chert; limestone conglomerate; dark limestone separated by thin shale; coarsely granular thick-bedded limestone; light gray-weathering massive limestone. Can be divided into three members between the southern Lenox Hill and Hill 5300 named Decie Ranch (base), Poplar Tank, and Sullivan Peak (top) Members. East of Hill 5300, the Poplar Tank tongues out into the Skinner Ranch and the formation is not divided. East of Leonard Mountain, Skinner Ranch tongues into the Hess Formation. Contains numerous fossils--brachiopods and fusulinids. Is correlated with the lower massive part of Bone Spring Formation of Sierra Diablo. Cross section. Of Leonardian, Early Permian age.

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

Skinner Ranch revised--includes newly named Dugout Mountain Member above the Sullivan Peak Member and below the lowest beds of the overlying Cathedral Mountain Formation (revised) west of the Lenox Hills on Dugout Mountain (vicinity of the Glass Mountains, Brewster Co, TX in Permian basin). This newly named interval includes the "Second" through "Fourth" limestone members of the old Leonard Formation (King, 1931), and the shaly intervals between them. The limestones on Dugout Mountain do not at all correspond with those in Lenox Hills (except for the first, the Sullivan Peak Member); the three limestone beds appear to thin and perhaps converge northeastward along the back of Dugout Mountain. They pinch out somewhere in the covered valley between Dugout Mountain and the Lenox Hills, and the shaly Dugout Mountain Member above the Sullivan Peak Member is only tentatively identified in the Lenox Hills. Skinner Ranch is undifferentiated in the middle of the Glass Mountains front. About a mi east of the Hess Ranch house it merges laterally into Hess Formation, and west of hill 5021 it splits into three members: basal Decie Ranch member ["western facies of the Hess" (King, 1931)], Poplar Tank Member, and the uppermost Sullivan Peak Member ["First Limestone" member of Leonard (King, 1931)]. Skinner Ranch overlies Lenox Hills Formation of Ross (1959); underlies Cathedral Mountain Formation (revised). Is of Permian (Leonardian) age.

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

Age of Skinner Ranch Formation in Glass Mountains (Brewster Co, TX in Permian basin) modified--removed from the lower Leonardian Series and placed in the Wolfcamp Series (Early Permian age). Overlies Wolfcampian Lenox Hills Formation; underlies Leonardian Cathedral Mountain Formation. In western part of report area, from Dugout Mountain through the Lenox Hills to hill 5021, three members are clearly defined (ascending): Decie Ranch, Poplar Tank, and Sullivan Peak Members. A fourth member, the Dugout Mountain Member, is recognized in Dugout Mountain. To east, Skinner Ranch interfingers with Hess Formation. Authors state that the Skinner Ranch Formation "contains many fossils related to the Wolfcamp below and some that link it to the upper part of the Pennsylvanian Gaptank Formation as well." Age based on preponderance of faunal evidence as indicated by the brachiopods. Fossils listed and discussed. Measured sections. Correlation chart.

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