Unit Name: Fort Vermilion Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: Middle Devonian (397.5 - 385.3 ma)
Province/Territory: Alberta
Originator: Law, J., 1955, p. 1927-1978.
Type Locality:
California Standard Steen River well in, Lsd. 2, Sec. 22, Twp. 117, Rge. 5W6M. between 1,350 and 1,357 m (4,429 and 4,452 ft).
Distribution:
The Fort Vermilion Formation reaches a maximum thickness of 37 m (120 ft) at the Hudson's Bay Fort Vermilion No. 1 well in Sec. 32, Twp. 104, Rge. 8W5M. It thins westward to a zero edge just west of the 6th Meridian, and also thins southward toward the Swan Hills area, where it is 8 m (25 ft) thick in the type Swan Hills well (Home Regent "A" Swan Hills, in Lsd. 10, Sec. 10, Twp. 67, Rge. 10W5M).
Lithology:
In the type well the Fort Vermilion consists of brown to white anhydrite with interbeds of dolomite or limestone; a thin bed of dolomite is some places separates the Fort Vermilion evaporites from the more open marine limestones of the Slave Point Formation.
Relationship:
The Fort Vermilion Formation is underlain by Watt Mountain shales of the Elk Point Group and is overlain conformably by basal calcarenites of the Slave Point (or lower Swan Hills) Formation. To the west the Fort Vermilion consists of open marine carbonates that are indistinguishable from the overlying Slave Point Formation.
History:
Law (1955) introduced the term Fort Vermilion Member of the Slave Point Formation for 7 m (23 ft) of anhydrite and dolomite at the base of the Slave Point Formation. Norris (1963) erected the Fort Vermilion Formation for a sequence of evaporites underlying the Slave Point Formation in Gypsum Cliffs area. Murray (1965) extended the use of the term Fort Vermilion Formation to the Swan Hills area, and Leavitt and Fischbuch (1968) included the Fort Vermilion Formation in the Beaverhill Lake Group.
Other Citations:
Law, 1955, p. 1927-1974; Leavitt and Fischbuch, 1968, p. 292; Murray, 1965; Norris, 1963, p. 59.
Source: CSPG Lexicon of Canadian Stratigraphy, Volume 4, western Canada, including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba; D.J. Glass (editor)
Contributor: N.R. Fischbuch
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 29 Apr 2003