Spruce Mountain SM-393 (Permian of the United States)

Where: Elko County, Nevada (40.5° N, 114.8° W: paleocoordinates 14.5° N, 36.6° W)

• coordinate based on nearby landmark

• local area-level geographic resolution

When: Gerster Formation (Park City Group), Wuchiapingian (259.9 - 254.2 Ma)

• 393 feet above base of Gerster Fm.

•Gerster Formation is correlated with the upper Phosphoria Formation (Rex Chert, Retort, Tosi) and other upper units in the Park City Group (Franson, Ervay). Those units are now Lopingian in age, following a latest Capitanian U/Pb age of 260.57 Ma in the upper Meade Peak Member. The upper age of the Gerster is unclear, and it may span much of the Lopingian, although the top is unconformable (overlying units are Smithian) so some or all of the Changhsingian may be missing. For now, all collections are assigned a Wuchiapingian age.

• group of beds-level stratigraphic resolution

Environment/lithology: marine; limestone

Size class: macrofossils

Preservation: replaced with silica

Collection methods: bulk, chemical,

Primary reference: B. R. Wardlaw. 1977. The biostratigraphy and paleoecology of the Gerster Limestone (Upper Permian) in Nevada and Utah. U.S.G.S. Open File Report 77(470):1-125 [D. Bottjer/M. Clapham/M. Clapham]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 39512: authorized by David Bottjer, entered by Matthew Clapham on 30.05.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

Anthozoa
 Rugosa -
Rugosa indet. horn coral
"Horn corals"
Bivalvia
 Pectinida -
Pectinoidea indet. Rafinesque 1815 scallop
Strophomenata
 Productida - Productidae
 Productida - Linoproductidae
cf. Grandaurispina "n. sp. A" Muir-Wood and Cooper 1960
Written "Grandaurispina" n. sp. A
 Productida - Aulostegidae
Ctenalosia fixata Cooper and Stehli 1955
Rhynchonellata
 Spiriferinida - Pennospiriferinidae
 Athyridida - Neoretziidae
Hustedia elongata Cooper 1953
"n. ssp."
 Athyridida - Athyrididae
Composita mira Girty 1899
 Terebratulida - Dielasmatidae