Castle Dale, Jensen Locality 1 (Cretaceous of the United States)

Also known as Red Seeps, BYU Loc. 664, UCM Loc. 83288; Jensen's Egg Site

Where: Emery County, Utah (39.2° N, 110.9° W: paleocoordinates 40.4° N, 72.9° W)

• coordinate estimated from map

• small collection-level geographic resolution

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

• Exact horizon could not be determined but it appears that the eggshells originated directly below the channel sands and so would occur in the uppermost Cedar Mountain beds.

•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.

• group of beds-level stratigraphic resolution

Environment/lithology: terrestrial; shale

• "Rocks are nearly horizonal, with channel sands occurring at random in soft shales of the fossiliferous area"

Size class: macrofossils

Collected by Jones & Jensen in 1965–1966

Collection methods: quarrying, surface (float),

Primary reference: R. P. Ratkevich. 1967. Fossil department. Rocks and Minerals 42(4):282-283 [M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 52973: authorized by Matthew Carrano, entered by Kaitlin Maguire on 30.08.2005

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Dinosauria -
 Theropoda - Elongatoolithidae
"Oolithes carlylensis n. sp." = Macroelongatoolithus carlylei
"Oolithes carlylensis n. sp." = Macroelongatoolithus carlylei Jensen 1970 theropod
BYU-E 200-201, BYU-VP 3699-3706; UCM 82008