Mackenzie, Trail River Section Unit 4 Road River Fm, Crepicephalus Fauna (Cambrian of Canada)

Where: Northwest Territories, Canada (66.4° N, 135.5° W: paleocoordinates 5.3° N, 60.0° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Road River Formation, Dresbachian (497.0 - 485.4 Ma)

• Collection taken from 1087 feet 0-1 in above base.

• formation-level stratigraphic resolution

Environment/lithology: deep subtidal; gray, argillaceous limestone and gray shale

• "Limestone, some argillaceous, very finely crystalline, grey, weathers grey, dark bluish grey, yellowish grey, bedding 2 to 24 inches; about 20% shaly argillite and shale, limy, dark grey, weather dark grey, yellowish grey. At 1,084-1,087, several thin bioclastic limestone beds, lenticular, bedding 2 to 6 inches, mostly composed of trilobite and brachiopod debris."

Size class: macrofossils

Collection methods: Collection also includes inarticulate brachiopod and trilobites. Probabaly Crepicephalus fauna.

Primary reference: B. S. Norford. 1963. Reconnaissance of the Ordovician and Silurian rocks of Northern Yukon Territory. Geological Survey of Canada Department of Mines and Technical Surveys, Paper 63(39):1-139 [S. Holland/T. Hanson/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 25605: authorized by Steven Holland, entered by Tori Hanson on 18.09.2002, edited by Austin Hendy

Creative Commons license: CC BY (attribution)

Taxonomic list

Trilobita
 Corynexochida - Illaenuridae
cf. Minicephalus sp. Lochmann and Lu 1960 trilobite
 Ptychopariida - Crepicephalidae
Crepicephalus sp. Owen 1852 trilobite
 Ptychopariida - Marjumiidae
? Shickshockia sp. Rasetti 1946 trilobite
 Ptychopariida - Tricrepicephalidae
Tricrepicephalus sp. Kobayashi 1935 trilobite
 Ptychopariida - Lonchocephalidae
? Lonchocephalus sp. Owen 1852 trilobite
 Ptychopariida - Kingstoniidae
Kingstonia sp. Walcott 1924 trilobite
 Olenida - Cedariidae
Cedaria cf. prolifica Walcott 1924 trilobite