Lake Simcoe Area, Ontario, Georgian Bay Formation, Upper Member (Ordovician of Canada)

Where: Ontario, Canada (43.7° N, 79.4° W: paleocoordinates 24.2° S, 51.9° W)

• coordinate estimated from map

• local area-level geographic resolution

When: upper Member (Georgian Bay Formation), Ashgill (449.5 - 443.7 Ma)

• member-level stratigraphic resolution

Environment/lithology: shallow subtidal; gray limestone

• Grey limestone, varying from calcarenite to crystalline limestone. Bedding thicknesses range from several inches to a foot and uppermost strata weather a rusty colour. Shale partings ranging from half an inch to 3 inches in thickness.

Size class: macrofossils

Primary reference: B. A. Liberty. 1969. Palaeozoic geology of the Lake Simcoe Area, Ontario. Geological Survey of Canada Memoirs (355)1-201 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 26304: authorized by Steven Holland, entered by Tori Hanson on 11.10.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Tetradium
  -
Tetradium approximatum
Bivalvia
 Ostreida - Pterineidae
Pterinea demissa
Pterinea demissa Conrad 1842 oyster
 Myalinida - Ambonychiidae
Byssonychia grandis
Byssonychia grandis Ulrich 1893 clam
 Modiomorphida - Modiomorphidae
"Whiteavesia pholadiformis" = Pholadomorpha pholadiformis
"Whiteavesia pholadiformis" = Pholadomorpha pholadiformis Hall 1851 clam
 Modiomorphida - Allodesmatidae
Ischyrodonta misneri
Cephalopoda
 Orthocerida - Orthoceratidae
Orthoceras lamellosum
 Pseudorthocerida - Spyroceratidae
Spyroceras parksi
Gastropoda
 Murchisoniina - Lophospiridae
"Lophospira tropidophora" = Paupospira tropidophora
"Lophospira tropidophora" = Paupospira tropidophora Meek 1873 snail
 Euomphalina - Platyceratidae
Cyclonema bilix
Cyclonema bilix Conrad 1842 snail
Strophomenata
 Strophomenida - Strophomenidae
Strophomena varsensis, Strophomena planumbona
Strophomena planumbona Hall 1847
S. planumbona erindalensis
Rhynchonellata
 Orthida - Plectorthidae
Hebertella occidentalis
 Atrypida - Anazygidae
Zygospira modesta, Catazyga headi
Catazyga headi Billings 1862
Stenolaemata
 Trepostomata - Batostomellidae
Bythopora meeki, Bythopora vacua, Bythopora similis
 Trepostomida - Monticuliporidae
Atactoporella densa, Homotrypella hospitalis, Homotrypa streetsvillensis
Stromatoporoidea
 Labechiida - Stromatoceriidae
Stromatocerium huronense
Stromatocerium huronense Billings 1865 stromatoporoid sponge
Anthozoa
 Stauriida - Stauriidae
Favistella calicina
 Stauriida - Streptelasmatidae
"Streptelasma rusticum" = Helicelasma rusticum
"Streptelasma rusticum" = Helicelasma rusticum Billings 1858 horn coral
 Stauriida - Columnariidae
Favistella ("Columnaria") alveolata
Favistella ("Columnaria") alveolata Goldfuss 1826 horn coral
 Sarcinulida - Syringophyllidae
"Calapoecia cribriformis" = Calapoecia huronensis
"Calapoecia cribriformis" = Calapoecia huronensis Billings 1865 tabulate coral