Perdrix Formation
{{Short description|Geologic formation}}
{{Infobox rockunit
| name = Perdrix Formation
| image =
| caption =
| type = Formation
| age = {{Fossil range|Frasnian}}
| prilithology = Shale
| otherlithology = Limestone
| namedfor = Roche à Perdrix
| namedby = P.E. Raymond, 1930Raymond, P.E. 1930. The Paleozoic Formations in Jasper Park, Alberta. American Journal of Science, 5th series, vol. 20, p. 289-300.
| region = Alberta
| country = Canada
| coordinates =
| unitof = Fairholme Group
| subunits =
| underlies = Mount Hawk Formation
| overlies = Maligne Formation, or Flume Formation
| thickness = Up to {{convert|140|m|ft}}
| extent =
| area =
| map =
| map_caption =
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The Perdrix Formation is a geologic formation of Late Devonian (Frasnian) age in the Western Canada Sedimentary Basin.{{Cite web|url=http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch12/ch_12.html|title=The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 12: Devonian Woodbend-Winterburn strata of the Western Canada Sedimentary Basin|author=Mossop, G.D. and Shetsen, I., (compilers), Canadian Society of Petroleum Geologists and Alberta Geological Survey|year=1994|accessdate=2014-10-17|url-status=dead|archiveurl=https://web.archive.org/web/20141018110640/http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch12/ch_12.html|archivedate=2014-10-18}} It named for Roche à Perdrix in Jasper National Park, Alberta, by P.E. Raymond in 1930. It includes fossils of marine animals.
Lithology
The Perdrix Formation was deposited in a marine basin and consists primarily of black, bituminous shales. The upper portion includes nodules and thin nodular beds of argillaceous limestone that increase in frequency upwards and laterally toward the reefs of the Cairn Formation.Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba, p. 925-926. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. {{ISBN|0-920230-23-7}}.
Thickness and Distribution
The Perdrix Formation is present as outcrops in the front and main ranges of the Canadian Rockies from the Kakwa Lakes area in northeastern British Columbia to the Ram River area of Alberta. It is also recognized in the subsurface immediately adjacent to the mountain front. Thicknesses range from about {{convert|80|m|ft}} to {{convert|140|m|ft}}.
Relationship to Other Units
The Perdrix Formation overlies the Maligne Formation or, where the Maligne is absent, the Flume Formation. It is conformably overlain by the Mount Hawk Formation and the contact is gradational. Laterally it interfingers with the Peechee Formation and the reefs of the Cairn Formation.
Paleontology
Tentaculids are common throughout the Perdrix Formation, and brachiopods and pelecypods are present in the more limestone-rich portions.
See also
{{Portal|Earth sciences|Canada|Paleontology}}
References
{{Reflist}}
- {{cite web|title= Fossilworks: Gateway to the Paleobiology Database|author= ((Various Contributors to the Paleobiology Database))|url= https://www.fossilworks.org|access-date= 17 December 2021}}
{{Western Canadian Sedimentary Basin|Canadian Rockies=yes}}
Category:Devonian southern paleotropical deposits
Category:Geologic formations of Alberta
Category:Western Canadian Sedimentary Basin
Category:Fossiliferous stratigraphic units of North America
Category:Paleontology in Alberta