District of Mackenzie, Sunblood Mountain Bathyurus Biofacies (A-220) (Ordovician of Canada)

Also known as A 220

Where: Northwest Territories, Canada (61.6° N, 125.7° W: paleocoordinates 6.8° N, 58.0° W)

• coordinate estimated from map

• outcrop-level geographic resolution

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

• bed-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

Preservation: replaced with silica

Collection methods: Also includes gastropods, 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 25925: 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
Rhynchonellata
 Rhynchonellida - Trigonirhynchiidae
Rostricellula sp.
Rostricellula sp. Ulrich and Cooper 1942
 Pentamerida - Camerellidae
Camerella sp.
Camerella sp. Billings 1859
Trilobita
 Lichida - Lichidae
Amphilichas sp.
Amphilichas sp. Raymond 1905 trilobite
 Proetida - Bathyuridae
Bathyurus sp.
Bathyurus sp. Billings 1859 trilobite
 Phacopida - Pterygometopidae
Calyptaulax sp.
Calyptaulax sp. Cooper 1930 trilobite