District of Mackenzie, Esbataottine Mountain Isotelus Biofacies (P-1585) (Ordovician of Canada)

Also known as P 1585, GSC loc. no. C-26314

Where: Northwest Territories, Canada (61.7° N, 125.9° W: paleocoordinates 7.0° N, 58.0° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Esbataottine Formation, Blackriveran (457.3 - 449.6 Ma)

• formation-level stratigraphic resolution

Environment/lithology: deep subtidal; argillaceous, silty limestone

• "[H]omogeneous, probably soft bottom, carbonate and mud substrate, deposited under quiet water conditions on a wide shelf ranging from the littoral to, possibly, deep sub-littoral zones."
• "[H]omogeneous sequence of micrites and microbiosparites, commonly silty and argillaceous. The bedding is regular to nodular and generally thin (3-8 cm) to medium (8-20 cm), rarely thickly bedded. Sand-size components are absent and more common biotic contributors to skeletal sands (pelmatozoans, heavy-shelled brachiopods, algae, corals, or stromatoporioids) are rare or absent."

Size classes: macrofossils, microfossils

Collection methods: Also includes leperditellid and oepikellid ostracods and bryozoans.

Primary reference: B. D. E. Chatterton and R. Ludvigsen. 1976. Silicified Middle Ordovician trilobites from the South Nahanni River Area, District of Mackenzie, Canada. Palaeontographica Abteilung A 154(1-3):1-106 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 25931: authorized by Steven Holland, entered by Tori Hanson on 28.09.2002, edited by Melanie Hopkins

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Ostracoda
 Palaeocopida - Leperditellidae
Leperditella mundula
 Hollinocopida - Oepikellidae
Oepikella cf. labrosa
Trilobita
 Corynexochida - Illaenidae
Nanillaenus sp., Nanillaenus mackenziensis, Bumastoides sp.
Nanillaenus sp. Jaanusson 1954 trilobite
Nanillaenus mackenziensis Chatterton and Ludvigsen 1976 trilobite
Bumastoides sp. Whittington 1954 trilobite
 Asaphida - Asaphidae
Isotelus sp., Isotelus parvirugosus, Nahannia sp., Nahannia humilisulcata
Isotelus sp. Dekay 1824 trilobite
Isotelus parvirugosus Chatterton and Ludvigsen 1976 trilobite
Nahannia sp. Chatterton and Ludvigsen 1976 trilobite
Nahannia humilisulcata Chatterton and Ludvigsen 1976 trilobite
 Phacopida - Cheiruridae
Ceraurinella nahanniensis
Ceraurinella nahanniensis Chatterton and Ludvigsen 1976 trilobite
Strophomenata
 Strophomenida - Strophomenidae
Strophomena sp.
Strophomena sp. Rafinesque and De Blainville 1824