Fernie Formation

Fernie Formation
Fernie Formation (Group)
Stratigraphic range: Jurassic

Fernie shales exposed in the mountains near Fernie
Type Geological formation
Sub-units Nordegg Member, Red Deer Member, Poker Chip Shale, Lille Member, Rock Creek Member, Highwood Member, Pigeon Creek Member, Ribbon Creek Member
Underlies Weary Ridge Member, Nikanassin Formation, Monteith Formation
Overlies Schooler Creek Group, Montney Formation, Rundle Group
Thickness up to 400 metres (1,310 ft)[1]
Lithology
Primary Shale
Other Sandstone, siltstone, limestone
Location
Named for Fernie, British Columbia
Named by Leach, 1914.
Coordinates 49°33′N 115°10′W / 49.55°N 115.16°W / 49.55; -115.16 (Fernie Formation)Coordinates: 49°33′N 115°10′W / 49.55°N 115.16°W / 49.55; -115.16 (Fernie Formation)
Region  Alberta,  British Columbia
Country  Canada

The Fernie Formation is a stratigraphical unit of Jurassic age in the Western Canadian Sedimentary Basin. In some interpretation it has Group status.

It takes the name from the town of Fernie, British Columbia, and was first defined by Leach in 1914.[2]

Contents

Lithology

The Fernie Formation is composed of brown and dark gray and black shale which can be fractured of papery. Phosphatic sandstone and limestone, as well as cherty limestone occur locally in the lower parts of the formation; siltstone, sandstones, coquinas and oolitic limestone interbeds can occur in the middle; glauconitic sandstone and siltstone can be present in the upper parts. The facies becomes transgressional at the top towards the eastern reaches of the formation, the direction from where most of the sediments originated. Five depositional cycles can be recognized within the formation.[1]

Distribution

The Fernie Formation reaches a maximum thickness of 400 metres (1,310 ft) near Mount Allan, and typically has 70 to 150m. It thins out toward the east, and disappears at the longitude of Calgary.[1] The formation is exposed in outcrops in south-eastern British Columbia in the Kootenays region, in the foothills and front ranges of the Canadian Rockies in southern Alberta and as far north as the Peace River Country in north-western British Columbia

Relationship to other units

The Fernie Formation is conformably overlain by the Weary Ridge Member of the Morrissey Formation in the south, by the Nikanassin Formation in central Alberta and by the Monteith Formation in north-eastern British Columbia.[1] It disconformably overlays the Triassic of upper Paleozoic units such as the Schooler Creek Group or the Montney Formation.

Subdivisions

The Fernie Group has the following sub-divisions from top to base:

Sub-unit Age Lithology Reference
Passage Beds Oxfordian to Portlandian dark grey splintery shale, silty beds [3]
Ribbon Creek Member Bathonian silty shale [4]
Green Beds Oxfordian glauconitic sandstone and siltstone, calcareous concretions, various fossils [5]
Grey Beds shale
Gryphaea Bed Bathonian coquina with Gryphaea impressimarginata, ammonites and belemnites, calcareous siltstone [6]
Corbula munda Beds Bathonian silty shale, calcareous sandstone [7]
Pigeon Creek Member Callovian calcareous siltstone and grey shale [8]
Highwood Member Bajocian dark grey shale, bioturbated sandstone [9]
Rock Creek Member Bajocian also called "Belemnite zone" - sandstone which may contain commercial gas reserves [10]
Lille Member Bajocian coquina with Gryphaea and Ostrea [11]
Poker Chip Shale Toarcian papery shale [12]
Red Deer Member Pliensbachian black shale, black laminated limestone [13]
Oxytoma Bed Sinemurian [14]
Nordegg Member Sinemurian dark chert, phosphate limestone, silty shale [15]

References

  1. ^ a b c d Lexicon of Canadian Geologic Units. "Fernie Formation". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:004906. Retrieved 2009-02-10. 
  2. ^ Leach, W.W., 1914. Blairmore map-area, Alberta; Geological Survey of Canada, Summary Report 1912, p. 234. with Map 107A, Blairmore, Alberta, Scale: 1 inch to 2 miles
  3. ^ Lexicon of Canadian Geologic Units. "Passage Beds". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:011576. Retrieved 2009-02-11. 
  4. ^ Lexicon of Canadian Geologic Units. "Ribbon Creek Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012726. Retrieved 2009-02-11. 
  5. ^ Lexicon of Canadian Geologic Units. "Green Beds". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:005908. Retrieved 2009-02-11. 
  6. ^ Lexicon of Canadian Geologic Units. "Gryphaea Bed". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:006023. Retrieved 2009-02-11. 
  7. ^ Lexicon of Canadian Geologic Units. "Corbula munda Beds". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:003356. Retrieved 2009-02-11. 
  8. ^ Lexicon of Canadian Geologic Units. "Pigeon Creek Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:011826. Retrieved 2009-02-11. 
  9. ^ Lexicon of Canadian Geologic Units. "Highwood Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:006578. Retrieved 2009-02-11. 
  10. ^ Lexicon of Canadian Geologic Units. "Rock Creek Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012885. Retrieved 2009-02-11. 
  11. ^ Lexicon of Canadian Geologic Units. "Lille Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:008464. Retrieved 2009-02-11. 
  12. ^ Lexicon of Canadian Geologic Units. "Poker Chip Shale". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012002. Retrieved 2009-02-11. 
  13. ^ Lexicon of Canadian Geologic Units. "Red Deer Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:012563. Retrieved 2009-02-11. 
  14. ^ Lexicon of Canadian Geologic Units. "Oxytoma Bed". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:011446. Retrieved 2009-02-11. 
  15. ^ Lexicon of Canadian Geologic Units. "Nordegg Member". http://cgkn1.cgkn.net/weblex/weblex_litho_detail_e.pl?00053:010885. Retrieved 2009-02-11. 

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