Shell Oil Co. Pine Field 43-22A, 9478'-9481' (Ordovician of the United States)

Where: Wibaux County, Montana (47.2° N, 110.2° W: paleocoordinates 7.4° S, 75.6° W)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Hintzeia celsaora trilobite zone, Deadwood Formation, Tulean (485.4 - 471.8 Ma)

• "L. Ord.. upper Arenig"

•Zone G

• group of beds-level stratigraphic resolution

Environment/lithology: lagoonal; fine-grained, micaceous, brown, gray limestone

• "sh, ls and congl., some ss. shelf lagoon, near shoreface. BA2. Cratonic shelf"
• dark gray-brown, fine-grained limestone with patches of sparry calcite, small (1 to 2 mm) lenses of green greasy micaceous clay with scattered carbonate rhombs; small pyrite blebs; very abundant trilobite pieces, about half showing wear

Size class: macrofossils

Primary reference: C. Lochman. 1966. Lower Ordovician (Arenig) faunas from the Williston Basin, Montana and North Dakota. Journal of Paleontology 40(3):512-548 [P. Wagner/P. Wagner/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 174361: authorized by Pete Wagner, entered by Pete Wagner on 10.11.2015

Creative Commons license: CC BY (attribution)

Taxonomic list

 Aulacopleurida - Hystricuridae
Psalikilus paraspinosum Hintze 1952 trilobite
Hystricurus "sp. A" Raymond 1913 trilobite
 Proetida - Bathyuridae
Licnocephala "sp. A" Ross 1951 trilobite
 Asaphida - Asaphidae
 Asaphida - Remopleurididae
Apatokephalus "sp. indet." Brögger 1896 trilobite
 Orthida - Plectorthidae
Nanorthis putilla Walcott 1924
 Lingulida - Obolidae
 Euomphalina - Macluritidae
"Lecanospira (Barnesella) aff. affinis" = Teiichispira affinis
"Lecanospira (Barnesella) aff. affinis" = Teiichispira affinis Billings 1865 snail
 Eogastropoda - Sinuopeidae
"Rhombella aff. umbilicata" = Euconia umbilicata
"Rhombella aff. umbilicata" = Euconia umbilicata Dake and Bridge 1932 snail
 Murchisoniina - Hormotomidae
Plethospira "sp. indet." Ulrich and Scofield 1897 snail