USGS D1958: Maastrichtian, Wyoming

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Polychaeta - Serpulimorpha
? Diploconcha sp.
originally entered as "? Diploconcha sp."
Cephalopoda - Ammonitida - Scaphitidae
Discoscaphites sp. Meek 1870
sp. nov.
Cephalopoda - Ammonitida - Baculitidae
Baculites grandis Hall and Meek 1854
Gastropoda - Naticidae
Euspira obliquata
Gastropoda - Neogastropoda - Fasciolariidae
Graphidula culbertsoni
Gastropoda - Neogastropoda - Melongenidae
Serrifusus dakotensis (Meek and Hayden 1856)
Gastropoda - Aporrhaidae
Drepanocheilus evansi
originally entered as "Drepanochilus evansi"
Gastropoda - Opisthobranchia - Scaphandridae
Ellipsoscapha occidentalis
Gastropoda - Opisthobranchia - Bullidae
Bullopsis aff. cretacea Conrad 1858
originally entered as "Bullopsis aff. cretacea"
Bivalvia - Nuculanida - Nuculanidae
Nuculana evansi
Bivalvia - Nuculida - Nuculidae
Nucula planimarginata Meek and Hayden 1857
Bivalvia - Myalinida - Inoceramidae
Inoceramus incurvus
? Inoceramus cf. fibrosus (Meek and Hayden 1857)
originally entered as "? Inoceramus cf. fibrosus"
Bivalvia - Pectinida - Oxytomidae
Oxytoma nebrascana (Evans and Shumard 1857)
Bivalvia - Pectinida - Anomiidae
Anomia sp. Linnaeus 1758
Bivalvia - Arcida - Cucullaeidae
Idonearca shumardi
spelled with current rank as Cucullaea (Idonearca)
see common names

Geography
Country:United States State/province:Wyoming County:Niobrara
Coordinates: 43.3° North, 104.3° West (view map)
Paleocoordinates:49.8° North, 78.5° West
Basis of coordinate:estimated from map
Geographic resolution:small collection
Time
Period:Cretaceous Epoch:Late/Upper Cretaceous
Stage:Maastrichtian 10 m.y. bin:Cretaceous 8
*Epoch:Senonian
Key time interval:Maastrichtian Ammonoid zone: Baculites eliasi
Age range of interval:72.10000 - 66.00000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Lewis Shale Member:Kara Bentonitic
Regional section:member Regional bed:137 - 189 ft
Regional order:top to bottom
Stratigraphic resolution:bed
Stratigraphy comments: Pierre shale, from ferro-calc concretions 137 - 189' below top of Kara member. Was upper unnamed shale of Pierre Shale, bed 95.
Lithology and environment
Primary lithology:gray lithified "shale"
Secondary lithology: "limestone"
Environment:offshore Tectonic setting:cratonic basin
Geology comments: "Shale. dark gray; weathers light medium gray; contains some brown weathering ls concretions 6 in thick and 9 in diam, which in upper few ft and at base are very fossiliferous."
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Collection methods:mechanical,field collection
Reason for describing collection:biostratigraphic analysis
Museum repositories:USGS
Collection method comments: "[collected] from upper few feet"
Taxonomic list comments:"The fossils are ordinarily well-preserved. Most of the cephalopod shells and the inner nacreous layer of Inoceramus are aragonitic, especially specimens from above the Red Bird Silty Member. Shell material and specimens from the Red Bird member and the upper 50' of the underlying Mitten Member is partially transformed to calcite...Ammonites...of the [mid-upper third] of the Mitten Member are...entirely aragonite whereas shell material [of underlying material] is completely transformed to calcite."
Metadata
Also known as:Pierre Shale (USGS D1958)
Database number:1583
Authorizer:J. Alroy Enterer:M. Sommers
Modifier:P. Wagner Research group:marine invertebrate
Created:1999-05-17 16:51:24 Last modified:2024-03-17 14:47:15
Access level:the public Released:1999-05-17 16:51:24
Creative Commons license:CC BY
Reference information

Primary reference:
45. J. R. Gill, W. A. Cobban, and P. M. Kier. 1966. The Red Bird Section of the Upper Cretaceous Pierre Shale in Wyoming. United States Geological Survey Professional Paper 393-A:1-73 [J. Alroy/M. Sommers/A. Clement]