MMMN 1-2653. Hecla Beds, Victoria Beach (Ordovician of Canada)

Where: Manitoba, Canada (50.7° N, 96.6° W: paleocoordinates 12.4° S, 59.8° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Dog Head Member (Red River Formation), Edenian (451.0 - 450.2 Ma)

• Hecla Beds, at the very base of Red River formation

• group of beds-level stratigraphic resolution

Environment/lithology: deep subtidal; bioturbated, dolomitic, argillaceous, calcareous mudstone

• Interestingly, small- and thin-shelled brachiopods (e.g., T clarksvillensis) are most abundant in the Dog Head Member but become increasingly scarce up-section in the Cat Head Member and even more so in the Selkirk Member, where large and gigantic forms predominate. A similarly low diversity and general scarcity are also observed

•in corals from the Dog Head and Cat Head members (Elias 1991). This indicates that the carbonate sediments of these two members may have accumulated in relatively deep waters during the early stages of the Tippecanoe transgression, when the rate of sediment accumulation lagged behind the rate of sea-level rise.

• Generally, the basal Red River Formation contains argillaceous interbeds of Winnipeg-type lithology, termed Hecla Beds by Fuller (1961 ), and represents a transitional zone between the two formations (McCabe, 1978).

•

•Jin & Zhan: The Dog Head and Cat Head members consist mainly of relatively dense, argillaceous, bioturbated mudstone, which is largely calcareous with some degree of dolomitization in the Winnipeg - southern Lake Winnipeg area but completely dolomitized in south-central Manitoba

Size class: macrofossils

Reposited in the GSC

Primary reference: J. Jin and R.-b. Zhan. 2001. Late Ordovician Articulate Brachiopods from the Red River and Stony Mountain Formations, Southern Manitoba. 1-117 [P. Wagner/P. Wagner/P. Wagner]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 166421: authorized by Pete Wagner, entered by Pete Wagner on 12.02.2015

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Rhynchonellata
 Orthida - Platyorthidae
Diceromyonia storeya
Diceromyonia storeya Okulitch 1943