Drakes Creek, USGS 1386: Morrowan, Arkansas
List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Cephalopoda
- Nautilida
- Koninckioceratidae
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Knightoceras oxylobatum
Miller and Downs 1948
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Cephalopoda
- Nautilida
- Ephippioceratidae
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Ephippioceras ferratum
(Cox 1857)
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Cephalopoda
- Bactritida
- Bactritidae
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? Bactrites redactus
Gordon 1964
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Cephalopoda
- Goniatitida
- Delepinoceratidae
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Proshumardites morrowanus
Gordon 1964
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Cephalopoda
- Pseudorthocerida
- Pseudorthoceratidae
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Mooreoceras normale
Miller et al. 1933
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synonym of Pseudorthoceras knoxense | |||||||
see common names |
Geography
Country: | United States | State/province: | Arkansas | County: | Madison |
Coordinates: | 36.0° North, 93.9° West (view map) | ||||
Paleocoordinates: | 8.7° South, 31.5° West | ||||
Basis of coordinate: | based on political unit | ||||
Geographic resolution: | small collection |
Time
Period: | Carboniferous | Epoch: | Pennsylvanian |
Stage: | Bashkirian | 10 m.y. bin: | Carboniferous 4 |
Key time interval: | Morrowan | ||
Age range of interval: | 323.20000 - 318.40000 m.y. ago |
Stratigraphy
Formation: | Hale | Member: | Prairie Grove | ||
Stratigraphic resolution: | group of beds | ||||
Stratigraphy comments: The type locality of the Hale formation is Hale Mountain in wester Washington County where it is relatively thick. Recent work has shown that two mappable members, the Cane Hill below and the Prairie Grove member above, can be recognized in Washington County. The Cane Hill member is as much as 65 feet in thickness and is composed largely of silt, silty sandstone, and fine-grained sandstone; locally there are beds of fossiliferous crossbedded limestone in the lower part. In the Harrison quadrangle, in Carroll and Boone Counties, the Hale formation as mapped by Purdue and Miser (1916) is overlain by the Atoka formation and contains a considerable amount of shale, particularly the lower part, which may either represent the Cane Hill member, or include the Imo formation and upper shale member of the Pitkin limestone, or parts of all three. The two members of the Hale formation can be recognized in Washington and Madison Counties, as well as in adjacent parts of Crawford County. In this region the Cane Hill member rests unconformably on the Pitkin limestone, or on the Fayetteville shale where the Pitkin has been cut out by erosion prior to Morrow deposition. The Prarie Grove member is overlain conformmably by the Bloyd shale. |
Lithology and environment
Primary lithology: | shelly/skeletal lithified "limestone" |
Secondary lithology: | "cross stratification",fine,medium lithified calcareous sandstone |
Includes fossils? | Y |
Lithology description: The Prairie Grove member,...,ranges in thickness from 600 to 200 feet and is composed almost entirely of fine- to medium-grained calcareous sandstone, commonly lamellar crossbedded or a honeycomb structure emphasized differentially on weathered surfaces. Lenses of fossiliferous, crinoidal, and oolitic limestone are rather common in the upper and, locally, in the lower parts. At some places Henbest (1953, p.1940,1941) has noted a basal conglomerate commonly made of pebbles and cobbles of quartzitic sandstone. This unit is quite fossiliferous, particularly where the limestone content is high and cephalopods are fairly common locally. | |
Environment: | shallow subtidal indet. |
Taphonomy
Modes of preservation: | body |
Size of fossils: | macrofossils |
Collection methods and comments
Collection methods: | field collection |
Reason for describing collection: | taxonomic analysis |
Museum repositories: | USGS |
Metadata
Also known as: | Locality H 12; Miser, Sept. 9, 1914 | ||
Database number: | 43374 | ||
Authorizer: | J. Alroy | Enterer: | C. Simpson |
Modifier: | C. Simpson | Research group: | marine invertebrate |
Created: | 2004-08-12 14:53:12 | Last modified: | 2004-08-12 17:53:12 |
Access level: | the public | Released: | 2004-08-12 14:53:12 |
Creative Commons license: | CC BY |
Reference information
Primary reference:
11419. | M. Gordon. 1964. Carboniferous Cephalopods of Arkansas. United States Geological Survey Professional Paper 460:1-322 [J. Alroy/C. Simpson/M. Clapham] |