Unit Name: Crowfoot Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Frasnian (385.3 - 374.5 ma)
Province/Territory: Alberta
Originator: Belyea, H.R. and McLaren, D.J., 1957.
Type Locality:
Royalite Crowfoot No. 2, in 4-4-21-19W4M Alberta, between 1,658.4 and 1,662.4 m (5,441 and 5,454 ft). Supplementary section in Socony Craigmyle No. 1, in 12-32-32-16W4M, between 1,452.4 and 1,490.5 m (4,765 and 4,890 ft).
Distribution:
Locally absent, 3.9 m (13 ft) thick at the type section, ranging up to 38 m (125 ft). The Crowfoot is equivalent to the Calmar and part of the Graminia fommations. It locally includes evaporite facies of the upper part of the Nisku Formation. To the south and east of the type area (in northern Montana, southern Saskatchewan and southwestern Manitoba) Crowfoot equivalents are present in the Torquay Formation.
Lithology:
Anhydrite, light grey to brown and red, grey silty dolomite, with thin siltstone lenses; green, grey and brown shale, in places containing coarse sand grains. In places consists of interbedded siltstone and green shale.
Relationship:
In the type area in southern Alberta the Crowfoot is overlain by the Stettler Formation and overlies the Arcs Member of the Southesk Formation.
Other Citations:
Belyea, in: McCrossan and Glaister (Eds.), 1964; Belyea and McLaren, 1957; Douglas, et al., 1970; Woodhead, 1960.
Source: CSPG Lexicon of Canadian Stratigraphy, Volume 4, western Canada, including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba; D.J. Glass (editor)
Contributor: H.R. Balkwill
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 29 Apr 2003