USGS D9239, Milwood Lake [Saratoga Chalk]: Late/Upper Campanian, Arkansas
collected by Clardy et al. 1974
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
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Cephalopoda
- Ammonitida
- Scaphitidae
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Hoploscaphites pumilis
(Stephenson 1941)
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| recombined as Hoploscaphites pumilus | |||||||
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Cephalopoda
- Ammonitida
- Nostoceratidae
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Nostoceras (Nostoceras) colubriformis
(Stephenson 1941)
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| original and current combination Nostoceras colubriformis | |||||||
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Nostoceras (Nostoceras) helicinum
(Shumard 1861)
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Nostoceras (Nostoceras) approximans
(Conrad 1855)
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Nostoceras (Nostoceras) pauper
(Whitfield 1892)
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| recombined as Nostoceras pauper | |||||||
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Nostoceras (Nostoceras) hyatti
(Stephenson 1941)
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| original and current combination Nostoceras hyatti | |||||||
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Didymoceras navarroense
(Shumard 1861)
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| synonym of Cirroceras conradi | |||||||
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Cephalopoda
- Ammonitida
- Baculitidae
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Baculites ovatus
(Say 1820)
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| see common names | |||||||
Geography
| Country: | United States | State/province: | Arkansas | County: | Hempstead |
| Coordinates: | 33.7° North, 94.0° West (view map) | ||||
| Paleocoordinates: | 37.8° North, 65.7° 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 basal 1.2 m (4 ft) of formation. | |||||
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: | Clardy et al. | Collection dates: | 1974 |
| Collection method comments: COLLECTOR: B.F. Clardy R.E Burkholder, and W.A. Cobban, 1974. 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: | 83051 | ||
| Authorizer: | A. Hendy | Enterer: | A. Hendy |
| Modifier: | J. Sessa | Research group: | marine invertebrate |
| Created: | 2008-08-06 09:59:16 | Last modified: | 2013-11-25 13:37:23 |
| Access level: | the public | Released: | 2008-08-06 09:59:16 |
| Creative Commons license: | CC BY |
Reference information
Primary reference:
| 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] |