Franson Member, Park City Formation of Montana (Permian of the United States)

Where: Montana (47.1° N, 109.4° W: paleocoordinates 17.9° N, 29.5° W)

• coordinate based on political unit

• basin-level geographic resolution

When: Franson Member (Park City Formation), Wuchiapingian (259.9 - 254.2 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; lime mudstone and grainstone

Size class: macrofossils

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 11279: authorized by Arnold Miller, entered by Chad Ferguson on 30.07.2001, edited by Matthew Clapham and Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

Anthozoa
 Rugosa -
Rugosa indet. horn coral
unclassified
  -
Porifera indet. Grant 1836
Scaphopoda
 Dentaliida - Prodentaliidae
"Plagioglypta canna" = Prodentalium canna
"Plagioglypta canna" = Prodentalium canna White 1874 tusk shell
 Dentaliida - Dentaliidae
Plagioglypta sp. Pilsbry 1898 tusk shell
Gastropoda
  - Turritellidae
Bellerophontoidea indet.2, "Knightites (Retispira) eximia" = Yochelsonellisa eximia
Bellerophontoidea indet.2 M'Coy 1851 horn snail
"Knightites (Retispira) eximia" = Yochelsonellisa eximia Yochelson 1960 horn snail
Bivalvia
 Nuculanida - Polidevciidae
Polidevcia cf. obesa White 1879 clam
 Trigoniida - Schizodidae
Schizodus sp. King 1844 clam
 Pholadomyida - Edmondiidae
 Cardiida - Kalenteridae
Permophorus albequus Beede 1907 clam
 Pectinida - Heteropectinidae
Heteropecten cf. vanvleeti1 Beede 1902 scallop
 Pectinida - Aviculopectinidae
Aviculopecten sp. M'Coy 1851 scallop
Stenolaemata
 Fenestrata -
Fenestrata indet. Elias and Condra 1957
 Trepostomata -
Trepostomata indet. Ulrich 1882
entered as "Terpostomata"
Rhynchonellata
 Athyridida - Athyrididae
Composita sp. Brown 1849
 Rhynchonellida - Wellerellidae
Wellerella cf. osagensis Shumard and Swallow 1858
 Spiriferida - Spiriferellidae
"Neospirifer pseudocameratus" = Timaniella pseudocamerata
"Neospirifer pseudocameratus" = Timaniella pseudocamerata Girty 1920
 Spiriferida - Trigonotretidae
Neospirifer sp. Fredericks 1919
Strophomenata
 Productida - Aulostegidae
Sphenosteges sp. Muir-Wood and Cooper 1960
 Productida - Productidae
Lingulata
 Lingulida - Lingulidae
Lingula sp. Bruguiére 1797
 Lingulida - Discinidae