Unit Name: Clausen Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Early Mississippian (359.2 - 345.3 ma)
Province/Territory: Northwest Territories
Originator: Harker, 1961; more complete description and type section in Harker, 1963.
Type Locality:
West side of Yohin Ridge, about 19 km (12 mi) south of South Nahanni River and about 35 km (22 mi) west of South Nahanni. Map 95G, 61 deg 06'N, 123 deg 55'W.
Distribution:
Recognition of the formation as defined is restricted to the area of distribution of the overlying Flett Fm and the underlying Yohin Fm; the latter unit in particular is limited to a relatively small area straddling the Yukon-British Columbia boundary. Within this limited area, measured thickness variations of the Clausen range from 152 to 172 m (550-565 ft). Equivalent shales of Kinderhook age are, however, widely distribution throughout Western Canada. The Clausen corresponds to map-unit 6 of Douglas and D.K. Norris (1959) and map-unit 31 of Douglas and D.K. Norris (1960) and map-unit 2 of Patton (1958).
Lithology:
Thinly laminated black shales, with a few calcareous layers and some beds of more resistant black mudstone. Shales are non-calcareous in type section, but elsewhere are variably calcareous and may contain interbedded siltstones.
Relationship:
Conformably overlies the Yohin Fm and is conformably overlain by the Flett Fm. Both formation boundaries appear to be transitional in character and may therefore be variable from point to point. The Yohin Fm equates to map-unit 5 of Douglas and D.K. Norris (1959), map-unit 30 of Douglas and D.K. Norris (1960), and to Unit 1 of Patton (1958). In age, the unit would appear to equate at least in part with the Banff Fm of Alberta. It is equivalent to the Etanda and Besa River formations.
Other Citations:
Bamber and Mamet, 1978; Douglas and D.K. Norris, 1959, 1960; Harker 1961, 1963; Patton, 1958; Pelzer, 1966.
Source: CSPG Lexicon of Canadian Stratigraphy, Volume 2, Yukon Territory and District of Mackenzie; L.V. Hills, E.V. Sangster and L.B. Suneby (editor)
Contributor: E.E. Pelzer; P.A. Monahan; L.V. Hills
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 29 Apr 2003