Thompson, USGS 14390: Morrowan, Arkansas

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Cephalopoda - Prolecanitida - Pronoritidae
Stenopronorites arkansiensis (Smith 1896)
recombined as Pseudopronorites arkansiensis
Cephalopoda - Goniatitida - Reticuloceratidae
Pygmaeoceras pygmaeum (Mather 1915)
recombined as Verneuilites pygmaeus
Cephalopoda - Goniatitida - Glaphyritidae
Glaphyrites globosus (Easton 1943)
recombined as Syngastrioceras globosum
Bisatoceras paynei Gordon 1964
recombined as Schartymites paynei
(1 measurement)
Cephalopoda - Goniatitida - Bisatoceratidae
Homoceratoides cracens Gordon 1964
Cephalopoda - Goniatitida - Wiedeyoceratidae
Gordonites matheri Gordon 1964
Cephalopoda - Pseudorthocerida - Pseudorthoceratidae
Pseudorthoceras knoxense (McChesney 1859)
Cephalopoda - Bactritida - Bactritidae
? Bactrites gaitherensis Gordon 1964
see common names

Geography
Country:United States State/province:Arkansas County:Madison
Coordinates: 35.9° North, 93.9° West (view map)
Paleocoordinates:8.8° South, 31.6° West
Basis of coordinate:stated in text
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:bed
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
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 11; Gordon, Payne, and Lewandoski, Apr. 23, 1953
Database number:43386
Authorizer:J. Alroy Enterer:C. Simpson
Modifier:C. Simpson Research group:marine invertebrate
Created:2004-08-12 17:52:37 Last modified:2004-08-12 20:52:38
Access level:the public Released:2004-08-12 17:52:37
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]