YPM 5154a-u, 20103, 20106 (Yale Peabody Museum) (Carboniferous to of the United States)

Also known as Sando et al. Horse Creek Loc.44

Where: Fremont County, Wyoming (43.7° N, 109.6° W: paleocoordinates 2.0° N, 39.2° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Anthracospirifer welleri - shawi zone, Horseshoe Member (Amsden Formation), Chesterian to Chesterian (335.5 - 321.8 Ma)

• Float probably about 90 ft above base of Amsden Fm. "Late Mississippian (Chesterian)."

• group of beds-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.

Reposited in the YPM

• "Collected by J.D. Love, 1937."

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 5718: authorized by John Alroy, entered by Mike Sommers on 17.11.1999

Creative Commons license: CC BY (attribution)

Taxonomic list

Rhynchonellata
 Athyridida - Athyrididae
Cleiothyridina hirsuta Hall 1857
ssp. darwinensis
Composita sigma Gordon 1975
 Spiriferida - Spiriferidae
Anthracospirifer shawi Gordon 1975
ssp. shawi
Strophomenata
 Productida - Productidae
 Productida - Productellidae