Perdrix Formation

From Wikipedia, the free encyclopedia
Perdrix Formation
Stratigraphic range: Frasnian
TypeFormation
Unit ofFairholme Group
UnderliesMount Hawk Formation
OverliesMaligne Formation, or Flume Formation
ThicknessUp to 140 metres (460 ft)
Lithology
PrimaryShale
OtherLimestone
Location
Region Alberta
Country Canada
Type section
Named forRoche à Perdrix
Named byP.E. Raymond, 1930[1]

The Perdrix Formation is a geologic formation of Late Devonian (Frasnian) age in the Western Canada Sedimentary Basin.[2] It named for Roche à Perdrix in Jasper National Park, Alberta, by P.E. Raymond in 1930.[1] It includes fossils of marine animals.[3]

Lithology[edit]

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.[3]

Thickness and Distribution[edit]

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 80 metres (260 ft) to 140 metres (460 ft).[3]

Relationship to Other Units[edit]

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.[3]

Paleontology[edit]

Tentaculids are common throughout the Perdrix Formation, and brachiopods and pelecypods are present in the more limestone-rich portions.[3]

See also[edit]

References[edit]

  1. ^ a b Raymond, P.E. 1930. The Paleozoic Formations in Jasper Park, Alberta. American Journal of Science, 5th series, vol. 20, p. 289-300.
  2. ^ 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 12: Devonian Woodbend-Winterburn strata of the Western Canada Sedimentary Basin". Archived from the original on 2014-10-18. Retrieved 2014-10-17.{{cite web}}: CS1 maint: multiple names: authors list (link)
  3. ^ a b c d e 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.