Also known as Loc. 6 (of Kennedy et al. 2000)
Where: Carter County, Montana (45.8° N, 105.1° W: paleocoordinates 51.9° N, 72.0° W)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: Didymoceras cheyennense ammonoid zone, Pierre Shale Formation, Late/Upper Campanian (83.5 - 70.6 Ma)
• STRATIGRAPHIC RELATIONS: From the Pierre Shale, for which lithostratigraphic relations are not discussed. AGE: Late Campanian, on the basis of ammonoid biostratigraphy; Didymoceras cheyennense zone. STRATIGRAPHIC POSITION: From limestone concretions 45 m below base of the Monument Hill Bentonitic Mbr.
• bed-level stratigraphic resolution
Environment/lithology: marine; lithified, concretionary, gray, calcareous shale
Size class: macrofossils
Preservation: mold/impression, concretion
Collected by Cobban in 1950; reposited in the USNM
Collection methods: surface (in situ),
• COLLECTOR: Cobban, 1950. REPOSITORY: USNM.
Primary reference: W. J. Kennedy, N. H. Landman, W. A. Cobban and G.R. Scott. 2000. Late Campanian (Cretaceous) heteromorph ammonites. Bulletin of the American Museum of Natural History 251:1-88 [A. Hendy/A. Hendy]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 88470: authorized by Austin Hendy, entered by Austin Hendy on 12.04.2009
Creative Commons license: CC BY (attribution)
Taxonomic list
Cephalopoda | |
Didymoceras cheyennense Meek and Hayden 1856 ammonite |