USGS 9732, Saratoga: Late/Upper Campanian, Arkansas
collected by Stephenson 1916

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Echinoidea - Spatangoida - Micrasteridae
Micraster americanus (Stephenson 1941)
Cephalopoda - Ammonitida - Scaphitidae
Hoploscaphites pumilis (Stephenson 1941)
Kennedy and Cobban 1993
recombined as Hoploscaphites pumilus
Cephalopoda - Ammonitida - Baculitidae
Baculites ovatus (Say 1820)
Kennedy and Cobban 1993
Cephalopoda - Ammonitida - Nostoceratidae
Nostoceras (Nostoceras) hyatti (Stephenson 1941)
Kennedy and Cobban 1993
original and current combination Nostoceras hyatti
Nostoceras (Nostoceras) approximans (Conrad 1855)
Kennedy and Cobban 1993
Didymoceras navarroense (Shumard 1861)
Kennedy and Cobban 1993
synonym of Cirroceras conradi
see common names

Geography
Country:United States State/province:Arkansas County:Howard
Coordinates: 33.8° North, 93.9° West (view map)
Paleocoordinates:37.9° North, 65.6° West
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period:Cretaceous Epoch:Late/Upper Cretaceous
Stage:Campanian 10 m.y. bin:Cretaceous 7
Key time interval:Late/Upper Campanian Ammonoid zone: Nostoceras hyatti
Age range of interval:83.60000 - 72.10000 m.y. ago
Stratigraphy
Geological group:Navarro Formation:Saratoga Chalk
Stratigraphic resolution:bed
Stratigraphy comments: 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 unknown position within formation of 6-16 m in thickness.
Lithology and environment
Primary lithology: lithified lime mudstone
Secondary lithology: lithified calcareous sandstone
Includes fossils?Y
Includes fossils?Y
Lithology description: SPECIFIC LITHOLOGY: Chalk and calcareous sand. LITHIFICATION: Lithified, on the basis of figured specimens.
Environment:carbonate indet.
Geology comments: ENVIRONMENT: Shallow marine cabonate setting.
Taphonomy
Modes of preservation:cast,mold/impression
Size of fossils:macrofossils
Preservation of anatomical detail:good
Collection methods and comments
Collection excludes:some macrofossils
Collection methods:surface (in situ),field collection
Reason for describing collection:taxonomic analysis
Museum repositories:USNM
Collectors:Stephenson Collection dates:1916
Collection method comments: COLLECTOR: L.W. Stephenson. REPOSITORY: USNM, Washington DC.
Taxonomic list comments:COVERAGE: Exhaustive for ammonoids, other groups may be present, but are not listed. NOMENCLATURE: An authoritative publication, with modern nomenclature and species-resolution identifications.
Metadata
Database number:83037
Authorizer:A. Hendy, M. Clapham Enterer:A. Hendy, M. Clapham
Modifier:M. Clapham Research group:marine invertebrate
Created:2008-08-06 09:05:59 Last modified:2018-11-23 01:03:42
Access level:the public Released:2008-08-06 09:05:59
Creative Commons license:CC BY
Reference information

Primary reference:

26335.1% 20600C. W. Cooke. 1953. American Upper Cretaceous Echinoidea. United States Geological Survey Professional Paper 254-A:1-44 [W. Kiessling/U. Merkel/M. Clapham]

Secondary references:

27893 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]