Rex Chert Member, Phosphoria Formation of Utah (Permian of the United States)

Where: Utah (39.6° N, 110.8° W: paleocoordinates 12.1° N, 34.4° W)

• coordinate based on political unit

• basin-level geographic resolution

When: Rex Chert Member (Phosphoria 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; chert and limestone

• Limestone present as lenses in the chert bed.

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 11233: authorized by Arnold Miller, entered by Chad Ferguson on 27.07.2001

Creative Commons license: CC BY (attribution)

Taxonomic list

Stenolaemata
 Trepostomata -
Trepostomata indet. Ulrich 1882
entered as "Terpostomata"
Rhynchonellata
 Rhynchonellida - Rhynchoporidae
Rhynchopora sp. King 1865
Lingulata
 Lingulida - Discinidae
Orbiculoidea sp. d'Orbigny 1847
Bivalvia
 Cardiida - Kalenteridae
Pseudopermophorus annettae Ciriacks 1963 clam
Gnathostomata
  -