{{Short description|Geological formation in Canada}} {{Use mdy dates|date=June 2025}} {{Infobox Rockunit | name = Rundle Group | image = MountRundle.jpg | caption = The massive limestone beds form outcrops at the top of Mount Rundle. | type = Geological formation | age = {{Fossil range|Middle Mississippian|Late Mississippian|Middle to Late Mississippian}} | period = Mississippian | prilithology = Limestone | otherlithology = Chert | namedfor = Mount Rundle | namedby = R.J.W. Douglas, 1953 | region = Alberta, British Columbia | country = Canada | coordinates = {{coord|51.15|N|115.50|W|display=inline,title}} | unitof = | subunits = Debolt, Shunda, Pekisko, Mount Head, Livingstone, Turner Valley, Prophet | underlies = Fernie Formation, Belloy Formation | overlies = Banff Formation | thickness = up to {{cvt|741|m|ft|-1}}<ref name=lexicon>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:013065 |title=Rundle Group |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 |archive-date=February 22, 2013 |archive-url=https://archive.today/20130222015657/http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:013065 |url-status=dead }}</ref> | extent = | area = | map = | map_caption = }} The '''Rundle Group''' is a stratigraphic unit of Mississippian age in the Western Canadian Sedimentary Basin.
It takes the name from Mount Rundle (itself taking the name from Robert Terrill Rundle), and was first described in outcrops at the northern side of the mountain in Banff National Park by R.J.W. Douglas in 1953.<ref>Douglas, R.J.W., 1953b. Carboniferous stratigraphy in the southern Foothills of Alberta; Alberta Soc. Petrol. Geol., 3rd Ann. Field Conf. Guidebook, p. 66–88.</ref>
==Lithology== The Rundle Group consists of massive limestone interbedded with dark argillaceous limestone. Chert nodules are observed in the shaley beds, and crinoids and brachiopods are observed in the clean massive beds.<ref name=lexicon/> Dolimitization is observed in the Elkton Member of the Turner Valley Formation.
==Distribution== The Rundle Group reaches a maximum thickness of {{convert|741|ft|m|-1}} at Tunnel Mountain. It thins out toward east and north and is completely eroded or absent in east central and only the lower part occurs in southern Alberta.<ref name=lexicon/>
==Relationship to other units==
The Rundle Group is disconformably overlain by the Rocky Mountain Formation in the front ranges of the Canadian Rockies and by the Fernie Formation in the foothills and by Cretaceous beds in the prairies. It conformably overlies the Banff Formation.<ref name=lexicon/>
The Rundle Group can be correlated with the Mission Canyon Formation in southern Saskatchewan, northeastern Montana and North Dakota.
===Subdivisions=== The Rundle Group includes the Mount Head Formation and Livingstone Formation in the Rocky Mountains; by the Turner Valley Formation, Shunda Formation and Pekisko Formation in the foothills and plains. It is equivalent to the Debolt Formation and Prophet Formation in north-eastern British Columbia and west-northern Alberta.<ref name="lexicon" /> Debolt, Shunda and Pekisko formations are staked in the Fort Nelson area.
====Canadian Rockies==== {|class="wikitable" |- ! Sub-unit !! Age !! Lithology !! Max.<br>Thickness !! Reference |- |Mount Head Formation || Visean ||Wileman Member - silty dolomite<br>Baril Member - ooid grainstone, dolomite<br>Salter Member - dolomite, boundstone and wackestone, ooid grainstone, anhydrite chert<br>Loomis Member - massive grainstone<br>Marston Member - microcrystalline dolomite, boundstone, breccia, ooid limestone, shale, marlstone<br>Opal Member - grainstone, subordinate marlstone, chert packstone and wackestone, shale, marlstone, breccia<br>Carnarvon Member - wackestone to packstone, shale interbeds|| {{cvt|7.6|m|ft|-1}}<br>{{cvt|39|m|ft|-1}}<br>{{cvt|67|m|ft|-1}}<br>{{cvt|101|m|ft|-1}}<br>{{cvt|68|m|ft|-1}}<br>{{cvt|161|m|ft|-1}}<br>{{cvt|90|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:010227 |title=Mount Head Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 }}</ref> |- |Livingstone Formation || Tournaisian to Visean || crinoidal limestone, massive limestone, thin argillaceous limestone beds, dolomite || {{cvt|452|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:008601 |title=Livingstone Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 |archive-date=July 7, 2012 |archive-url=https://archive.today/20120707092317/http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:008601 |url-status=dead }}</ref> |- |}
====Foothills and plains==== {|class="wikitable" |- ! Sub-unit !! Age !! Lithology !! Max.<br>Thickness !! Reference |- | Turner Valley Formation || Visean || crinoidal limestone and crystalline dolomite; two porous intervals are separated by a middle tight unit; diagenetically dolomitized in west southern Alberta; Lower porous zone is defined as Elkton Member || {{cvt|110|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:015517 |title=Turner Valley Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 }}</ref> |- | Shunda Formation || Tournaisian to Visean || argillaceous limestone and dolomite, siltstone, sandstone, shale, breccia, anhydrite || {{cvt|122 |m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:013726 |title=Shunda Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 }}</ref> |- | Pekisko Formation || Tournaisian || Upper Pekisko - lithographic limestone<br>Lower Pekisko - massive crinoidal limestone || {{cvt|134|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:011645 |title=Pekisko Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 }}</ref> |- |}
====Deep basin==== {|class="wikitable" |- ! Sub-unit !! Age !! Lithology !! Max.<br>Thickness !! Reference |- | Debolt Formation || Meramecian || Upper Debolt - crystalline dolomite, anhydrite, micritic limestone<br>Lower Debolt - cherty bioclastic (crinoidal) limestone, argillaceous in the north || {{cvt|366|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:003842 |title=Debolt Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 |archive-date=July 11, 2012 |archive-url=https://archive.today/20120711082741/http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:003842 |url-status=dead }}</ref> |- | Prophet Formation || middle Tournaisian to late Visean || chert, skeletal to ooid limestone, shale, marlstone, dolomite || {{cvt|760|m|ft|-1}} |<ref>{{Cite web |url=http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012238 |title=Prophet Formation |author=Lexicon of Canadian Geologic Units |access-date=February 12, 2009 }}</ref> |- |}
==References== {{reflist}} {{WCSB|Northwest_Plains=yes|South AB=yes|Canadian Rockies=yes}}
Category:Geologic groups of Alberta Category:Geologic groups of British Columbia Category:Carboniferous Alberta Category:Carboniferous British Columbia Category:Limestone groups of Canada Category:Chert groups