Portage Chute Formation, Member 2 (South Knife River Exposure) (Ordovician to of Canada)

Where: Manitoba, Canada (58.5° N, 95.0° W: paleocoordinates 7.4° S, 52.2° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: 2 Member (Portage Chute Formation), Edenian to Edenian (451.0 - 445.5 Ma)

• member-level stratigraphic resolution

Environment/lithology: dolomitic, gray limestone

• Environmental call by T. Hanson
• "Gray- to buff-weathering, light-gray, microcrystalline, slightly dolomitic limestone in beds 1 inch to 2 feet thick. Fragmental organic material is common. Closely-spaced, rusty-weathering, anastamosing laminae within the limestone are characteristic and in many places give the member a nodular appearance upon weathering."

Primary reference: S. J. Nelson. 1963. Ordovician paleontology of the Northern Hudson Bay lowland. Geological Society of America Memoir 90:1-152 [S. Holland/T. Hanson/T. Hanson]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 13656: authorized by Steven Holland, entered by Tori Hanson on 16.04.2002

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Chlorophyceae
  - Receptaculitidae
Receptaculites sp.
Receptaculites sp. Defrance 1827
Cephalopoda
 Discosorida - Westonoceratidae
Westonoceras nelsonense, Winnipegoceras dowlingi, Winnipegoceras laticurvatum
 Discosorida - Cyrtogomphoceratidae
Cyrtogomphoceras turgidum, Cyrtogomphoceras rotundum, Cyrtogomphoceras foerstei
 Multiceratoidea - Clinoceratidae
Whiteavesites winnipegensis
 Oncocerida - Oncoceratidae
Digenuoceras latum
 Multiceratoidea - Apsidoceratidae
Charactoceras manitobense n. sp.
 Actinocerida - Gonioceratidae
Lambeoceras landerense, Lambeoceras baffinense
Lambeoceras baffinense Miller et al. 1954
Gastropoda
 Euomphalina - Macluritidae
"Maclurites manitobensis" = Maclurina manitobensis, Maclurites altus
"Maclurites manitobensis" = Maclurina manitobensis Whiteaves 1890 snail
Maclurites altus Wilson 1931 snail
 Euomphalina - Holopeidae
Holopea gigantea n. sp.
Holopea gigantea n. sp. Nelson 1963 snail
 Murchisoniina - Hormotomidae
Hormotoma winnipegensis
Hormotoma winnipegensis Whiteaves 1897 snail
 Murchisoniina - Subulitidae
Fusispira gigantea
Fusispira gigantea Wilson 1938 snail
 Murchisoniina - Trochonematidae
Trochonema coxi
Trochonema coxi Wilson 1938 snail
Rhynchonellata
 Orthida - Platyorthidae
Diceromyonia sp.
Diceromyonia sp. Wang 1949
Strophomenata
 Strophomenida - Sowerbyellidae
"Thaerodonta sp." = Eochonetes
"Thaerodonta sp." = Eochonetes Reed 1917
Anthozoa
 Stauriida - Streptelasmatidae
Grewingkia robusta
Grewingkia robusta Whiteaves 1896 horn coral
 Stauriida - Stauriidae
Palaeophyllum stokesi
 Favositida - Favositidae
? Saffordophyllum portagechutense n. sp.
? Saffordophyllum portagechutense n. sp. tabulate coral
 Heliolitida - Halysitidae
Manipora amicarum, Manipora feildeni, Catenipora agglomeratiformis, Catenipora robusta, Catenipora aequabilis
Manipora amicarum tabulate coral
Manipora feildeni tabulate coral
Catenipora agglomeratiformis Hall 1900 tabulate coral
Catenipora robusta Wilson 1926 tabulate coral
Catenipora aequabilis Teichert 1937 tabulate coral
 Heliolitida - Plasmoporidae
Plasmopora lambei
Plasmopora lambei tabulate coral
 Sarcinulida - Syringophyllidae
Calapoecia arctica
Calapoecia arctica tabulate coral
Calapoecia arctica Troedsson(?)