Retort Phosphatic Shale Member, Phosphoria Formation of Wyoming (Permian of the United States)

Where: Wyoming (43.0° N, 106.8° W: paleocoordinates 13.1° N, 30.2° W)

• coordinate based on political unit

• basin-level geographic resolution

When: Retort Phosphatic Shale Member (Phosphoria Formation), Lopingian (259.9 - 252.2 Ma)

• Davydov et al. 2017 dated an ash bed in the upper Meade Peak Member at 260.57 ± 0.07 / 0.14 / 0.31 Ma, indicating that the Meade Peak is as young as uppermost Capitanian.

• member-level stratigraphic resolution

Environment/lithology: marine; claystone and black limestone

• Very few of the individual phosphatic shales actually contain fossils, indicating a low oxygen/reducing envirnment.
• Alternation of claystone and dark, fine grained Limestone.

Size classes: macrofossils, mesofossils

Primary reference: E. L. Yochelson and D. H. Van Sickle. 1968. Biostratigraphy of the Phosphoria, Park City, and Shedhorn Formations; Geology of Permian Rocks in the Western Phosphate Field. United States Geological Survey Professional Paper 313(D):572-660 [A. Miller/C. Ferguson/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 11224: authorized by Arnold Miller, entered by Chad Ferguson on 26.07.2001

Creative Commons license: CC BY (attribution)

Taxonomic list

• Some fossils on this list are thought to be assigned to the wrong formation (probably Ervay): Composita cf. mira, Composita sp., ?Liosotella sp.. Others show evidence of wear/reworking.
Lingulata
 Lingulida - Discinidae
 Lingulida - Lingulidae
Lingula sp. Bruguiére 1797
Strophomenata
 Productida - Paucispiniferidae
? Liosotella sp. Cooper 1953
 Productida - Echinoconchidae
 Productida - Linoproductidae
Rhynchonellata
 Spiriferida - Trigonotretidae
Neospirifer sp. Fredericks 1919
 Spiriferinida - Spiriferinidae
Spiriferina sp. d'Orbigny 1847
 Athyridida - Athyrididae
Composita sp. Brown 1849
Composita cf. mira Girty 1899
Stenolaemata
 Fenestrata -
Fenestrata indet. Elias and Condra 1957
 Trepostomata -
Trepostomata indet. Ulrich 1882
entered as "Terpostomata"
Bivalvia
 Nuculanida - Polidevciidae
Polidevcia sp. Tschernyschev 1943 clam
Polidevcia cf. obesa White 1879 clam
Polidevcia bellistriata Stevens 1858 clam
 Nuculida - Nuculidae
Nuculopsis sp. Girty 1912 nut clam
Nuculopsis poposiensis Branson 1930 nut clam
 Pholadomyida - Edmondiidae
Cephalopoda
 Belemnoidea -
Belemnitida indet. Zittel 1895 belemnite
Gnathostomata
  -