Where: Washington County, Utah (37.3° N, 113.8° W: paleocoordinates 42.4° N, 80.4° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Iron Springs Formation, Coniacian (89.8 - 86.3 Ma)

• "About 2500 feet above the base of a section of undifferentiated Colorado and Montana beds" according to Brown. Given the section is about 1000 m thick, this places the locality near the top of the formation (Iron Springs Formation based on geological map). Base of Iron Springs Formation at Gunlock constrained by 101.7 +/- 0.42 Ma 40Ar/39Ar laser fusion dating of sanidine crystals from a bentonite bed (Dyman et al., 2002). Palynomorph assemblage from shale in the lower Iron Springs indicates a Cenomanian-Turonian age. Can be correlated to Baseline Sandstone in Muddy Mountains, which contain tuffs dated by K-Ar biotite at 96.9 and 95.8 Ma (lower white member) and 93.1 Ma (upper red member) (Fillmore, 1991). Top is Coniacian or Santonian (Eaton, 1999).

• bed-level stratigraphic resolution

Environment/lithology: terrestrial; lithified, concretionary, ferruginous, yellow sandstone

Size class: macrofossils

Preservation: mold/impression, trace

Collected by J.B. Reeside, C.E. Dobbin in 1936

Primary reference: R. W. Brown. 1941. The comb of a wasp nest from the Upper Cretaceous of Utah. American Journal of Science 239:54-56 [M. Clapham/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 127633: authorized by Matthew Clapham, entered by Amy Delelli on 19.05.2012

Creative Commons license: CC BY (attribution)