{{Short description|Stratigraphic unit of Permian age in Canada}} {{Infobox rockunit | name = Ishbel Group | image = Johnston cascade.JPG | imagesize = 180px | caption = Calcareous siltstone exposed along the Johnston Creek west of Banff | type = Group | age = {{Fossil range|Permian|Permian|Permian}} | period = Permian | prilithology = Limestone, dolomite, sandstone | otherlithology = Chert, siltstone | namedfor = Mount Ishbel | namedby = A. McGugan | year_ts = 1963 | region = Alberta, British Columbia | country = Canada | coordinates = | unitof = | subunits = | underlies = Spray River Group | overlies = Tunnel Mountain Formation, Kananaskis Formation | thickness = Up to about {{convert|425|m|ft|abbr=on}}<ref name=lexicon/> | extent = Western Canadian Sedimentary Basin | area = | map = | map_caption = }}
The '''Ishbel Group''' is a stratigraphic unit of Permian age in the Western Canadian Sedimentary Basin. It is present in the Canadian Rockies of Alberta and British Columbia. First defined by A. McGugan in 1963,<ref>McGugan, A., 1963. A Permian brachiopod and fusulinid fauna from Elk Valley, British Columbia, Canada. Journal of Paleontology, v. 37, p. 621-627.</ref> it is named for Mount Ishbel of the Sawback Range in Banff National Park, and parts of the group were first described in the vicinity of the mountain at Ranger Canyon and Johnston Canyon.<ref name=Glass>Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. {{ISBN|0-920230-23-7}}.</ref>
==Lithology== The Ishbel Group is composed of carbonate rocks (limestone and dolomite) and sandstone, with minor chert and siltstone. <ref name=lexicon>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:007039 |title=Ishbel Group |author=Lexicon of Canadian Geologic Units |access-date=2010-01-01 }}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref><ref name=Glass /> Depositional conditions were similar to those of the Phosphoria Formation to the south in United States.<ref name=Glass />
==Paleontology== Among the fossils that have been found in the Ishbel Group are corals, bryozoa, crinoids, and conodonts,<ref name=Glass /> as well as productid, chonetid and spiriferid brachiopods, omphalotrochid gastropods, and edestid elasmobranch fish.<ref name=paleo>{{Cite web|url=http://jpaleontol.geoscienceworld.org/cgi/content/abstract/42/5/1123|title=Biostratigraphy and faunas of the Permian Ishbel Group, Canadian Rocky Mountains |author=Journal of Paleontology|access-date=2010-01-10}}</ref>
==Distribution== The Ishbel Group reaches a maximum thickness of up to about 425 metres (1400 ft). It is present in the front ranges of the Canadian Rockies as far north as the Peace River.<ref name=lexicon/><ref name=Glass />
==Subdivisions==
{|class="wikitable" |- ! Sub-unit !! Age !! Lithology !! Max.<br>Thickness !! Reference |- |Kindle Formation || Asselian to early Artinskian || siltstone, shale || {{convert|200|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:007624|title=Kindle Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Belloy Formation || Permian || limestone, dolomite, and sandstone || {{convert|274|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:001143|title=Belloy Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09|archive-url=https://archive.today/20120708060843/http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:001143|archive-date=2012-07-08|url-status=dead}}</ref> |- |Fantasque Formation || Permian || spicular chert, shale, and siltstone || {{convert|55|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:004826|title=Fantasque Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Mowitch Formation || Roadian to Wordian || sandstone with gypsum || {{convert|76|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:010334|title=Mowitch Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Ranger Canyon Formation || Roadian to Wordian || dark chert, silicified sandstone, evaporite minerals || {{convert|30|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012488|title=Ranger Canyon Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Ross Creek Formation || late Sakmarian to Artinskian || shaly siltstone, calcareous siltstone, silty carbonate, phosphatic coquinas || {{convert|143|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012974|title=Ross Creek Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Telford Formation || Asselian to Sakmarian || sandy limestone and dolomite || {{convert|259|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:015017|title=Telford Formation|author=Lexicon of Canadian Geologic Units |access-date=2010-01-09}}</ref> |- |Johnston Canyon Formation || late Sakmarian to Artinskian || phosphatic siltstone, calcareous siltstone, and silty limestone and dolomite || {{convert|57 |m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:007213|title=Johnston Canyon Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |- |Belcourt Formation || Asselian to Sakmarian || silty dolomite with chert || {{convert|130|m|ft|-1|abbr=on}} |<ref>{{Cite web|url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:001090|title=Belcourt Formation|author=Lexicon of Canadian Geologic Units|access-date=2010-01-09}}{{Dead link|date=January 2026 |bot=InternetArchiveBot }}</ref> |}
==Relationship to other units== The Ishbel Group is disnconformably overlain by the Spray River Group and unconformably overlies the Tunnel Mountain Formation and the Kananaskis Formation.<ref name=lexicon/> It is partly equivalent to the Phosphoria Formation of Montana, Idaho, Wyoming, and Utah.<ref name=Glass />
==References== {{reflist}}
{{Western Canadian Sedimentary Basin|Liard_River=yes|Canadian Rockies=yes}}
Category:Geologic groups of British Columbia Category:Geologic groups of the Northwest Territories Category:Geologic groups of Alberta Category:Permian northern paleotemperate deposits Category:Permian British Columbia Category:Permian Alberta Category:Limestone groups of Canada Category:Dolomite formations of Canada Category:Sandstone groups of Canada Category:Chert groups Category:Siltstone groups