A0439. Junction Cliff (Ordovician of Canada)

Where: Quebec, Canada (49.8° N, 64.4° W: paleocoordinates 22.7° S, 39.0° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Hercochitina crickmayi other zone, Grindstone Member (Vaureal Formation), Richmondian (449.6 - 445.5 Ma)

• Collection A439 of Dewing 1999. Same collection names are used by Jin 1989, Jin and Zhan 2008, and Li and Copper 2006. Paraorthograptus pacificus zone.

•

•The collection is noted by Dewing to be from the Grindstone to Velleda mbrs. We marked here the lowest Mbr. because we do not know which one the fossils came from.

• bed-level stratigraphic resolution

Environment/lithology: lithified, bioturbated, coarse-grained, sandy, calcareous lime mudstone

• Member description taken from 2007 Long. Tempestite frequency curves: a key to Late Ordovician and Early Silurian subsidence, sea-level change, and orbital forcing in the Anticosti foreland basin, Quebec, Canada. Can. J. Earth Sci. Vol. 44, 413-431. "The Grindstone Member, at its type section on the north-east coast of Anticosti Island, consists of >14 m of lami-nated to thin-bedded, very fine sandstones (subfeldspathic to feldspathic bioarenites) and minor laminated calcareous mudstones. These mixed siliciclastic–carbonate sandstones appear to be restricted to the east end of the island; within 15 km of the type section they pass into sandy limestones. To the west, at Vauréal Falls, they are dominated by highly bioturbated thin-bedded micrites, interbedded with thin to thick beds of calcarenite of coarse sand to granule grade. At the west end of the island the member consists of 21 m of predominantly laminated to thin-bedded planar to wavy laminate (irregular, subnodular) micrites, with abundant bioturbation. Grainstones are rare and are typically discontinuous lenticular."

Size classes: macrofossils, mesofossils

Preservation: original calcite

Collected by P. Copper

Collection methods: bulk,

Primary reference: K. Dewing. 1999. Late Ordovician and Early Silurian strophomenid brachiopods of Anticosti Island, Quebec, Canada. In A. D. McCracken (ed.), Palaeontographica Canadiana 17:1-143 [S. Finnegan/S. Finnegan]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 158581: authorized by Seth Finnegan, entered by Seth Finnegan on 21.07.2014, edited by Pete Wagner

Creative Commons license: CC BY (attribution)

Taxonomic list

• Brachiopods only.
Show authors, comments, and common names
Strophomenata
 Orthotetida - Chilidiopsidae
Coolinia gamachiana
Coolinia gamachiana Twenhofel 1928
This occurrence is not recorded in Dewing 1999.
 Strophomenida - Sowerbyellidae
Eochonetes glabra, Sowerbyella (Eochonetes) sp.
Eochonetes glabra Shaler 1865
Rhynchonellata
 Athyridida - Meristellidae
Hindella umbonata
Hindella umbonata Billings 1862
 Orthida - Platystrophiidae
Vinlandostrophia regularis
 Orthida - Plaesiomyidae
Plaesiomys anticostiensis
 Orthida - Hesperorthidae
Ptychopleurella lamellosa, Barbarorthis laurentina
Barbarorthis laurentina Billings 1857
 Orthida - Dalmanellidae
Onniella tricapitata
Onniella tricapitata Jin and Zhan 2008
1 shell.
 Orthida - Rhipidomellidae
Mendacella uberis
Mendacella uberis Billings 1866
3 conjoined shells, 1 dorsal valve in A439a; >30 conjoined shells, ventral valves, and dorsal valve in A439b.
 Pentamerida - Parastrophinidae
Parastrophinella reversa
Parastrophinella reversa Billings 1857
This occurrence is not recorded in Dewing 1999.