Where: Hempstead County, Arkansas (33.7° N, 93.7° W: paleocoordinates 37.8° N, 65.4° W)
• coordinate based on nearby landmark
• outcrop-level geographic resolution
When: Nostoceras hyatti ammonoid zone, Saratoga Chalk Formation (Navarro Group), Late/Upper Campanian (83.5 - 70.6 Ma)
• STRATIGRAPHIC RELATIONS: From the Saratoga Chalk, which regionally overlies the Marlbrook Marl, and is overlain by the Nacatoch Sand Fm, all of the Navarro Gp. AGE: Late Campanian on the basis of ammonite biostratigraphy; Nostoceras hyatti zone. STRATIGRAPHIC POSITION: From 6.1-7.6 m (20-25 ft) above base.
• bed-level stratigraphic resolution
Environment/lithology: lithified lime mudstone and lithified, calcareous sandstone
Size class: macrofossils
Preservation: cast, mold/impression
Collected by Cobban in 1973; reposited in the USNM
Collection methods: surface (in situ),
• COLLECTOR: W.A. Cobban, 1973. REPOSITORY: USNM, Washington DC.
Primary reference: W. J. Kennedy and W. A. Cobban. 1993. Ammonites from the Saratoga Chalk (Upper Cretaceous), Arkansas. Journal of Paleontology 67(3):404-434 [A. Hendy/A. Hendy]more details
Purpose of describing collection: taxonomic analysis
PaleoDB collection 83044: authorized by Austin Hendy, entered by Austin Hendy on 06.08.2008
Creative Commons license: CC BY (attribution)
Taxonomic list
Cephalopoda | |
Pachydiscus (Pachydiscus) arkansanus Stephenson 1941 ammonite | |
"Nostoceras (Nostoceras) pauper" = Nostoceras pauper, Nostoceras (Nostoceras) helicinum
"Nostoceras (Nostoceras) pauper" = Nostoceras pauper Whitfield 1892 ammonite
Nostoceras (Nostoceras) helicinum Shumard 1861 ammonite |