UM Collections (unlisted numbers - Univ. MO, Columbia) (Carboniferous to of the United States)

Also known as Sando et al. Amsden Hill Loc.24

Where: Fremont County, Wyoming (42.6° N, 108.7° W: paleocoordinates 0.8° N, 39.5° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Anthracospirifer welleri-shawi zone, Horseshoe Member (Amsden Formation), Chesterian to Chesterian (339.4 - 314.6 Ma)

• Purple limestone float below red shale in lower part of Amsden Fm. "Late Mississippian (Chesterian)."

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified, red, silty, sandy, calcareous shale and gypsiferous, shelly/skeletal limestone

• horseshoe: predominantly fissile, platy or blocky siltstone, shale, and mudstone. weathers bright red to grayish red or purple. thin beds and lenses of platy, white to red, fine grained, commonly calcareous quartz sandstone occur sporadically throughout member. thin beds of silty, sandy, or argillaceous limestone are rare in central wy, significant proportion in western wy. dolomite is a rare constituent. limestone beds are either fine grained and unfossiliferous or fine to medium grained and contain a shelly fauna. anhydrite and gypsum present at several localities. represents offshore marine facies of the transgressing amsden sea.

Collection methods: "Fossils listed by Morey, 1935, p474-482."

Primary reference: W. J. Sando, M., J.r. Gordon, and J. T. Dutro. 1975. Stratigraphy and geologic history of the Amsden Formation (Mississippian and Pennsylvanian) of Wyoming. United States Geological Survey Professional Paper 848A:1-83 [J. Alroy/M. Sommers/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 5689: authorized by John Alroy, entered by Mike Sommers on 15.11.1999

Creative Commons license: CC BY (attribution)

Taxonomic list

unclassified
  -
Ostracoda
 Palaeocopida - Amphissitidae
 Palaeocopida - Kirkbyidae
 Platycopida - Sansabellidae
 Platycopida - Paraparchitidae
 Podocopida - Bairdiocyprididae
 Podocopida - Acratiidae
 Beyrichicopida - Aechminellidae
"Balantoides quadrilobatus" = Aechminella
"Balantoides quadrilobatus" = Aechminella ostracod