District of Mackenzie, Sunblood Mountain (A-160) (Ordovician of Canada)

Also known as A 160

Where: Northwest Territories, Canada (61.6° N, 125.8° W: paleocoordinates 5.5° N, 59.9° W)

• coordinate stated in text

• outcrop-level geographic resolution

When: Esbataottine Formation, Chazyan (468.1 - 460.9 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 class: macrofossils

Preservation: replaced with silica

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 26056: authorized by Steven Holland, entered by Tori Hanson on 01.10.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

 Corynexochida - Styginidae
Failleana calva Chatterton and Ludvigsen 1976 trilobite
 Corynexochida - Illaenidae
Nanillaenus mackenziensis, "Bumastus (Bumastoides) lenzi" = Bumastoides lenzi
Nanillaenus mackenziensis Chatterton and Ludvigsen 1976 trilobite
"Bumastus (Bumastoides) lenzi" = Bumastoides lenzi Chatterton and Ludvigsen 1976 trilobite
 Phacopida - Pterygometopidae
Calyptaulax callirachis Cooper 1953 trilobite
 Phacopida - Cheiruridae
Ceraurinella nahanniensis Chatterton and Ludvigsen 1976 trilobite
Ceraurinella kingstoni Chatterton and Ludvigsen 1976 trilobite
 Asaphida - Asaphidae
Isotelus parvirugosus Chatterton and Ludvigsen 1976 trilobite
 Asaphida - Remopleurididae
Remopleurides pattersoni Chatterton and Ludvigsen 1976 trilobite