Amerada, Herman-May No.1 Fryburg Area 13,231'-13,235' ft (Ordovician of the United States)

Where: Billings County, North Dakota (48.0° N, 102.9° W: paleocoordinates 11.9° S, 74.5° W)

• coordinate based on political unit

• outcrop-level geographic resolution

When: Tesselacauda trilobite zone, Deadwood Formation, Stairsian (485.4 - 478.6 Ma)

• "L. Ord. m. Arenig"; Zone E

• bed-level stratigraphic resolution

Environment/lithology: transition zone or lower shoreface; limestone and shale

• "sh., ls and ss. ? lower shoreface or nearshore shelf lagoon. cratonic shelf"
• dense, gray-brown limestone in roller-shaped pebbles in medium-grained limestone, large grains and patches of glauconite abundant; some lenses of fine carbonaceous shales in the glauconite patches, pyrite very rare

Size classes: macrofossils, mesofossils

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 414: authorized by Jack Sepkoski, entered by Mike Sommers on 03.12.1998

Creative Commons license: CC BY (attribution)

Taxonomic list

• "Lochman-Balk and Wilson, 1967. Biostrat. lists"
Trilobita
 Corynexochida - Leiostegiidae
Lloydia (Evansaspis) formosa trilobite
originally Lloydia
 Aulacopleurida - Hystricuridae
Hystricurus sp. Raymond 1913 trilobite
Rhynchonellata
 Pentamerida - Clarkellidae
 Orthida - Plectorthidae
Nanorthis putilla Walcott 1924
originally Nanorthis
Lingulata
 Lingulida - Obolidae
Gastropoda
 Euomphalina - Raphistomatidae
"Raphistomina cf. sinclairensis" = Ceratopea sinclairensis
"Raphistomina cf. sinclairensis" = Ceratopea sinclairensis Kobayashi 1955 snail
originally Raphistomina
 Bellerophontida - Bucanellidae
Bucanella aff. nana Meek 1871 snail
originally Bucanella
 Bellerophontida - Tropidodiscidae
Tropidodiscus sp. Meek and Worthen 1866 snail
Conodonta
 Protopanderodontida - Protopanderodontidae
Drepanodus sp. Pander 1856 conodont
Eocrinoidea
  -
Eocrinoidea indet. Jaekel 1918
eocrinoids