| Attawapiskat Formation | |
|---|---|
| Stratigraphic range: Silurian | |
| Type | Geological formation |
| Location | |
| Region | Ontario |
| Country |  Canada |
The Attawapiskat Formation is a geologic formation in Ontario. It preserves fossils dating back to the Silurian period.
| Attawapiskat Formation | |
|---|---|
| Stratigraphic range: Silurian | |
| Type | Geological formation |
| Location | |
| Region | Ontario |
| Country | Canada |
The Attawapiskat Formation is a geologic formation in Ontario. It preserves fossils dating back to the Silurian period.
The Attawapiskat Formation encompasses a large portion of the Hudson Bay Basin. The formation remains visible from northern Ontario. A small portion of the formation does extend onto Nunavut territory.
It is widely believed that the formation originally deposited on a shallow rimmed shelf, followed by the development of barrier reefs into an nonlinear and uncoordinated "belt" around the Hudson Basin. Within the Hudson Bay Lowlands, the formation consists of dolomite and limestone rich in both coral and sponge. The formation is a haven for lithotopes, or media for sediments to deposit, with various types including:
The formation's depth reaches 62 meters at its deepest.
Color key
| Notes Uncertain or tentative taxa are in small text; |
| Brachiopods | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Eocoelia | E. akimiskii | Inter-reef beds of the formation, on Akimiski Island. [1] | Over 300 specimens. [1] | ||
| Erilevigatella | E. euthylomata | [2] | |||
| Gypidula | G. akimiskiformis | [2] | |||
| Meristina | M. expansa | Ekwan River. [3] | Now deemed a junior synonym of Pentameroides septentrionalis. | ||
| Pentameroides | P. septentrionalis | Ekwan River and Attawapiskat River. [3] | |||
| Protanastrophia | P. repanda | [4] | |||
| Reticularia | R. septentrionalis | Ekwan River. [3] | Now deemed a junior synonym of Pentameroides septentrionalis. | ||
| Sapelnikovia | S. (=Reveroides) norfordi | Attawapiskat River. [3] | Now deemed a junior synonym of Pentameroides septentrionalis. | ||
| Trilobites | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Acidaspis | A. sp. | Ekwan River at portage at Strong Rapids. [5] | |||
| Chiozoon | C. cf. cowiei | Ekwan River at portage at Strong Rapids. [5] | |||
| Dicranopeltis | D. sp. | Ekwan River at portage at Strong Rapids. [5] | |||
| Ekwanoscutellum | E. ekwanensis | Limestone Island, Severn River. [5] | "Nested stacks of mostly inverted (concave-up) large sclerites, the majority of which are pygidia". [6] | A scutelluine. | |
| Meroperix | M. aquilonarius | Ekwan River at portage at Strong Rapids. [5] | [6] | A scutelluine. | |
| Opoa | O. sp. | Ekwan River at portage at Strong Rapids. [5] | |||
| Perryus | P. severnensis | Limestone Island, Severn River. [5] | Several cranidia, pygidia and disarticulated exoskeletons. [5] | An encrinurid. |  |
| Stenopareia | S. sp. | Ekwan River at portage at Strong Rapids. [5] | [6] | An illaenid. | |
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Hudson Bay, sometimes called Hudson's Bay, is a large body of saltwater in northeastern Canada with a surface area of 1,230,000 km2 (470,000 sq mi). It is located north of Ontario, west of Quebec, northeast of Manitoba and southeast of Nunavut, but politically entirely part of Nunavut. It is an inland marginal sea of the Arctic Ocean. It drains a very large area, about 3,861,400 km2 (1,490,900 sq mi), that includes parts of southeastern Nunavut, Alberta, Saskatchewan, Ontario, Quebec, all of Manitoba, and parts of the U.S. states of North Dakota, South Dakota, Minnesota, and Montana. Hudson Bay's southern arm is called James Bay.
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The Thunder Bay Limestone is a geologic formation in Michigan. It preserves fossils dating back to the Devonian period.
The Georgian Bay Formation is a geologic formation in Michigan and Ontario. It preserves fossils dating back to the Ordovician period. The type locality of the formation is on East Meaford Creek, south shore of Nottawasaga Bay, Georgian Bay.
The Merrimack Formation is a geologic formation in Quebec. It preserves fossils dating back to the Silurian period.
The Gun River Formation is a geologic formation in Quebec. It preserves fossils dating back to the early Silurian period.
The Jupiter Formation is a geologic formation in Quebec, well-exposed in the southern third of Anticosti Island and lying in the St Lawrence River Valley. It preserves fossils dating back to the Silurian period.
The Becscie Formation is a geologic formation in Quebec. It preserves fossils dating back to the early Silurian period.
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