Palliser Formation

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Palliser Formation
Stratigraphic range: Famennian
Lake Minnewanka in 1902.jpg
Type section near Lake Minnewanka
Type Geological formation
Sub-units Moro Member, Costigan Member
Underlies Exshaw Formation
Overlies Alexo Formation
Thickness up to 580 metres (1,900 ft)[1]
Lithology
Primary Limestone, dolostone
Other Anhydrite
Location
Coordinates 51°16′08″N 115°16′30″W / 51.26877°N 115.27490°W / 51.26877; -115.27490 (Palliser Formation)Coordinates: 51°16′08″N 115°16′30″W / 51.26877°N 115.27490°W / 51.26877; -115.27490 (Palliser Formation)
Region  Alberta
Country  Canada
Type section
Named for Palliser Range
Named by H.H. Beach, 1943[2]

The Palliser Formation is a stratigraphic unit of Late Devonian (Famennian) age in the Western Canada Sedimentary Basin.[3] It is a thick sequence of limestone and dolomitic limestone that is present in the Canadian Rockies and foothills of western Alberta. Tall cliffs formed of the Palliser Formation can be seen throughout Banff and Jasper National Parks.

The formation was named for the Palliser Range in Banff National Park (which in turn took its name from John Palliser, the leader of the 1850s Palliser Expedition), by H.H. Beach in 1943.[2] The type locality was defined in 1994 by Meijer Drees and Johnston in the "Devil's Gap" section south of Mount Costigan of the Palliser Range, north of Lake Minnewanka.[4]

Lithology and paleontology[edit]

The Palliser Formation was deposited in a marine environment as an extensive carbonate shelf.[5] It is subdivided into the Morro Member (the lower part) and the Costigan Member (the upper part).[6] The Morro Member consists of massive, fine-grained limestone and dolomitic limestone. It contains remains of brachiopods, crinoids, gastropods, ostracods and conodont elements. The Costigan is less dolomitic, more argillaceous, and more fossiliferous than the Morro. It contains remains of brachiopods, crinoids, conodont elements, nautiloids, bryozoans, stromatoporiods and stromatolites.[4][1] Anhydrite beds can occur in both members.[7]

Distribution and thickness[edit]

The Palliser Formation is present throughout the main and front ranges of the Canadian Rockies, where it reaches a maximum thickness of 580 metres (1,900 ft), as well as in the subsurface in the foothills, where it is up to 240 metres (790 ft) thick.[1]

Relationship to other units[edit]

The Palliser Formation is disconformably overlain by the Exshaw Formation and conformably underlain by the Alexo Formation. It is equivalent to the Wabamun Group in central Alberta, to the middle part of the Three Forks Formation in Saskatchewan and Montana and to the Tetcho Formation and Kotcho Formation in the Fort Nelson area of British Columbia.[1][7]

References[edit]

  1. ^ a b c d Lexicon of Canadian Geologic Units. "Palliser Formation". Retrieved 2009-03-01. 
  2. ^ a b Beach, H.H., 1943. Moose Mountain and Morley map-areas, Alberta; Geological Survey of Canada, Memoir 236, 74 p.
  3. ^ Mossop, G.D. and Shetsen, I., (compilers), Canadian Society of Petroleum Geologists and Alberta Geological Survey (1994). "The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 13: Devonian Wabamun Group of the Western Canada Sedimentary Basin". Retrieved 2014-10-18. 
  4. ^ a b Meijer Drees, N.C. and Johnston, D.I. 1994. Type Section and conodonts biostratigraphy of the Upper Devonian Palliser Formation, southwestern Alberta. Bulletin of Canadian Petroleum Geology. 42:1. P 55-62.
  5. ^ Beales, F.W. 1954. The Palliser Banks in the Late Devonian seas of southwestern Alberta. Alberta Society of Petroleum Geologists Bulletin, vol. 2, no. 10, p. 1-5.
  6. ^ DeWit, R.W., and McLaren, D.J. 1950. Devonian Sections in the Rocky Mountains between Crowsnest Pass and Jasper, Alberta. Geological Survey of Canada, Paper 50-23.
  7. ^ a b 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.