USGS Mesozoic Loc. 28644 - Twin Creek Limestone (Jurassic of the United States)

Where: Rich County, Utah (41.5° N, 111.3° W: paleocoordinates 33.5° N, 51.7° W)

• coordinate estimated from map

When: Sliderock Member (Twin Creek Limestone Formation), Bajocian (170.3 - 168.3 Ma)

• Upper part from 62 ft of medium- to thin-bedded limestone

Environment/lithology: marine; limestone

• medium- to thin-bedded limestone

Size class: macrofossils

Preservation: mold/impression

Collected by R.W. Imlay in 1962; reposited in the USNM

Primary reference: R. W. Imlay. 1967. Twin Creek Limestone (Jurassic) in the Western Interior of the United States. United States Geological Survey Professional Paper 540:1-105 [S. Holland/P. Monarrez]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 167101: authorized by Steven Holland, entered by Pedro Monarrez on 07.03.2015

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Bivalvia
 Cardiida - Arcticidae
Pronoella sp.
Pronoella sp. Fischer 1887 clam
 Cardiida - Anthracosiidae
"Pleuromya subcompressa" = Myacites (Pleuromya) subcompressa
"Pleuromya subcompressa" = Myacites (Pleuromya) subcompressa Meek 1873 clam
 Trigoniida - Trigoniidae
"Myophorella (Promyophorella) montanaensis" = Trigonia montanaensis
"Myophorella (Promyophorella) montanaensis" = Trigonia montanaensis Meek 1873 clam
 Ostreida - Gryphaeidae
Gryphaea planoconvexa fraterna
Cephalopoda
 Ammonitida - Otoitidae
Megasphaeroceras cf. rotundum
Megasphaeroceras cf. rotundum Imlay 1961 ammonite
 Ammonitida - Stephanoceratidae
Stemmatoceras aff. albertense
 Ammonitida - Sphaeroceratidae
? Eocephalites sp., Eocephalites primus
? Eocephalites sp. Imlay 1967 ammonite
indet. sp. B and C
Eocephalites primus Imlay 1967 ammonite