D 828 CO (Ordovician of the United States)

Also known as Ninemile Shale, Bed D828CO; USGS D 828-CO

Where: Nevada (37.0° N, 116.0° W: paleocoordinates 5.8° S, 85.2° W)

• coordinate estimated from map

• hand sample-level geographic resolution

When: Pseudocybele nasuta trilobite zone, Ninemile Formation (Pogonip Group), Blackhillsian (474.9 - 470.0 Ma)

• Listed as Lower Arenig; local series:Zone J; C28

• group of beds-level stratigraphic resolution

Environment/lithology: slope; poorly lithified, green shale and lithified, concretionary, silty limestone

• Environment listed as upper slope, Zone 5
• Papery shale, weathers olive green, interlayered in equal parts with nodular silty limestone

Size classes: macrofossils, mesofossils

Preservation: trace

Primary reference: R. J. Ross, Jr. and C. R. Longwell. 1964. Middle and Lower Ordovician Formations in Southernmost Nevada and Adjacent California. United States Geological Survey Bulletin 1180-C:C1-C101 [S. Finnegan/S. Finnegan/J. Marcot]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 77181: authorized by Phil Novack-Gottshall, entered by Paul Hearn on 28.12.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

• Dominant taxa?; probably zone J age (Pseudocybele nasuta zone); approx. equivalent to Didymograptus protobifidus age
Show authors, comments, and common names
Trilobita
 Proetida - Dimeropygidae
Dimeropygiella sp., Ischyrotoma sp.
Dimeropygiella sp. Ross 1951 trilobite
Ischyrotoma sp. Raymond 1925 trilobite
 Proetida - Telephinidae
Carolinites sp.
Carolinites sp. Kobayashi 1940 trilobite
 Asaphida - Asaphidae
Lachnostoma sp., "Kirkella sp." = Ptyocephalus, Protopresbynileus sp.
Lachnostoma sp. Ross 1951 trilobite
"Kirkella sp." = Ptyocephalus Agassiz 1843 trilobite
Protopresbynileus sp. Hintze 1954 trilobite
 Trinucleida - Raphiophoridae
Ampyx sp.
Ampyx sp. Dalman 1827 trilobite
Rhynchonellata
 Orthida - Hesperonomiidae
Hesperonomia sp.
Hesperonomia sp. Ulrich and Cooper 1936