USGS 16215-PC: Morrowan, Wyoming

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Stacheiinae indet.
marine alga
Conodonta - Ozarkodinida - Idiognathodontidae
Streptognathodus parvus
Idiognathoides corrugata
Idiognathoides sinuata
Strophomenata - Productida - Productellidae
Antiquatonia cf. coloradoensis
Rhynchonellata - Athyridida - Athyrididae
Composita ovata Mather 1915
Rhynchonellata - Orthida - Schizophoriidae
Schizophoria cf. texana
unclassified
cf. Palaeonubecularia sp. Reitlinger 1950
Palaeotextulariidae
Palaeotextularia ex gr. consobrina
Palaeotextularia ex gr. longiseptata
Biseriamminidae
Lipinella sp.
(nom. nud.)
Biseriella moderata
Biseriella parva (Chernysheva 1948)
Globivalvulina sp. Schubert 1921
Eostaffellidae
Eostaffella sp. Rauser-Chernousova 1948
Tuberitinidae
Eotuberitina sp.
Tuberitina sp.
Earlandiidae
Earlandia sp.
Archaediscidae
Asteroarchaediscus bachkiricus
Asteroarchaediscus sp.
Neoarchaediscus sp.
Endothyridae
Endothyra sp.
Globoendothyra sp.
Archaesphaeridae
Diplosphaerina sp. Derville 1952
see common names

Geography
Country:United States State/province:Wyoming County:Sheridan
Coordinates: 44.9° North, 107.3° West (view map)
Paleocoordinates:4.5° North, 34.3° West
Basis of coordinate:estimated from map
Geographic resolution:small collection
Time
Period:Carboniferous Epoch:Pennsylvanian
Stage:Bashkirian 10 m.y. bin:Carboniferous 4
*Period:Late/Upper Carboniferous *Epoch:Bashkirian
*Local age/stage:Morrowan
Key time interval:Morrowan
Age range of interval:323.20000 - 318.40000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Amsden Member:Ranchester
Stratigraphic resolution:bed
Stratigraphy comments: Limestone about 100 ft above base of Amsden Fm. "Pennsylvanian (Morrowan)."
Lithology and environment
Primary lithology:lenticular,concretionary,gray,yellow lithified sandy,carbonaceous dolomite
Secondary lithology:green,red "shale"
Includes fossils?Y
Lithology description: ranchester: heterogenous sequence of interbedded cherty dolomite and limestone, sandstone, and shale. carbonate rocks predominate; thin- to thick-bedded, fine grained to coarsely crystalling, yellowish-gray weathering dolomite and dolomitic limestone are generally much more abundant than thin-bedded, fine- to medium-grained, light-gray to purple weathering limestone. carbonate beds, particularly dolomites, contain abundant gray, brown or jasperoid chert in small nodules, irregular lenses and irregular networks. red and green shale in thin beds and partings are commonly interbedded with the carbonate rocks, particularly in the upper half, and may compose significant thicknesses of the member at some localities. thin beds of fine- to medium-grained, white to pink sandstone occur throughout the member but are most abundant in the upper half. quartz sand is also a minor constituent of some of the carbonate beds. anhydrite was reported as a minor constituent of some dolomite beds.
Environment:offshore shelf Tectonic setting:cratonic basin
Taphonomy
Modes of preservation:body
Collection methods and comments
Collection methods:field collection,survey of museum collection
Reason for describing collection:biostratigraphic analysis
Museum repositories:USGS
Collection method comments: "Collected by M. Gordon, Jr. and others, 1955."
Metadata
Also known as:Sando et al. Amsden Creek Loc.67
Database number:5731
Authorizer:J. Alroy Enterer:M. Sommers
Modifier:C. Visaggi Research group:marine invertebrate
Created:1999-11-17 15:52:22 Last modified:2004-03-11 16:25:11
Access level:the public Released:1999-11-17 15:52:22
Creative Commons license:CC BY
Reference information

Primary reference:
349. W. J. Sando, M., J.r. Gordon, and J. T. Dutro. 1975. Stratigraphy and geologic history of the Amsden Formation (Mississippian and Pennsylvanian) of Wyoming. United States Geological Survey Professional Paper 848A:1-83 [J. Alroy/M. Sommers/P. Wagner]