Cifelli #2 Eolambia caroljonesa Quarry (22.2) (Cretaceous of the United States)

Also known as CEUM locality 42em432v, Eolambia II, Eo2

Where: Emery County, Utah (38.7° N, 111.3° W: paleocoordinates 40.0° N, 73.4° W)

• coordinate stated in text

• small collection-level geographic resolution

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

• 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.

• bed-level stratigraphic resolution

Environment/lithology: channel lag; pebbly, carbonaceous mudstone

• a "mudflat-transgressive lag deposition system" with local conditions suggestive of lacustrine final deposition as a regressive lag

Size classes: macrofossils, mesofossils

Preservation: replaced with calcite, replaced with silica, replaced with pyrite

Collection methods: quarrying, surface (in situ), mechanical,

Primary reference: J. R. Garrison, Jr., D. B. Brinkman, D. J. Nichols, P. Layer, D. L. Burge and D. Thayn. 2007. A multidisciplinary study of the Lower Cretaceous Cedar Mountain Formation, Mussentuchit Wash, Utah: a determination of the paleoenvironment and paleoecology of the Eolambia caroljonesa dinosaur quarry. Cretaceous Research 28:461-494 [M. Carrano/M. Carrano]more details

Purpose of describing collection: taphonomic analysis

PaleoDB collection 73612: authorized by Matthew Carrano, entered by Matthew Carrano on 21.06.2007, edited by Philip Mannion

Creative Commons license: CC BY (attribution)

Taxonomic list

unclassified
  -
Actinopteri
 Neopterygii -
 Lepisosteiformes - Lepisosteidae
Lepisosteus sp. Agassiz 1843 gar
 Lepisosteiformes -
cf. Lepidotes sp. Agassiz 1832 gar
 Holostei -
Amiiformes indet. Hay 1929 bowfin
Reptilia
 Theropoda - Dromaeosauridae
Dromaeosauridae indet. Colbert and Russell 1969 maniraptoran
listed as Dromaeosaurinae in Fig. 14
Richardoestesia cf. isosceles Sankey 2001 maniraptoran
 Theropoda -
cf. Paronychodon sp. Cope 1876 maniraptoran
 Ornithischia -
Eolambia caroljonesa Kirkland 1998 ornithopod
 Ornithischia - Hypsilophodontidae
Hypsilophodontidae indet. hypsilophodontid
 Loricata -
Mesoeucrocodylia indet. Whetstone and Whybrow 1983 crocodilian
Bernissartia "sp. 1" Dollo 1883 crocodilian
Eusuchia indet. Huxley 1875 crocodilian