Also known as Cedar Mountain Formation

Where: Emery County, Utah (39.1° N, 111.0° W: paleocoordinates 40.3° N, 73.0° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Mussentuchit Member (Cedar Mountain Formation), Early/Lower Cenomanian (99.6 - 93.5 Ma)

• Kirkland et al. 2016 stated that Tempskya are only known from the Mussentuchit Member within the Cedar Mountain Formation. This is recently believed to be Cenomanian in age according to Tucker et al. 2020.

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•A radiometric age of 98.37 ± 0.07 Ma was obtained by the OMNH from volcanic ash within the Mussentuchit Member (Cifelli and others, 1997, 1999). Additional ages by Garrison and others (2007) ranging from 96.7 ± 0.5 to 98.2 ±0.6 Ma indicate that the Mussentuchit Member was deposited over an interval of 1.5 Ma during the early Cenomanian and supports a correlation with the siliceous marine Mowry Shale to the north, which is well-constrained from 40Ar/39Ar sanidine ages obtained from bentonite beds that bracket the Mowry in Wyoming; the basal Arrow Creek Bentonite is 98.5 ± 0.5 Ma and the capping Clay Spur Bentonite is 97.2 ± 0.7 Ma (Obradovich, 1993; Ogg and Hinnov, 2012; Sprinkel and others, 2012) near the base of the Upper Cretaceous. Tucker et al. 2020 also suggested a likely depositional age of ~96-94Ma for the Musseuntuchit member.

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• formation-level stratigraphic resolution

Environment/lithology: fluvial-lacustrine; sandstone and gray, green shale

Size class: mesofossils

Preservation: original carbon

Collection methods: bulk,

Primary reference: W. D. Tidwell and G. F. Thayn. 1985. Flora of the Lower Cretaceous Cedar Mountain Formation of Utah and Colorado, Part IV. Palaeopiceoxylon thinosus (Protopinaceae). The Southwestern Naturalist 30(4):525-532 [B. Tiffney/J. Fosdick/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 31193: authorized by Bruce Tiffney, entered by Julia Fosdick on 22.04.2003, edited by Matthew Carrano

Creative Commons license: CC BY (attribution)