Unit Name: Doig Formation
Unit Type: Lithostratigraphic
Rank: Formation
Status: Formal
Usage: Currently in use
Age Interval: middle Anisian - Ladinian (244.1 - 228.7 ma)
Province/Territory: Alberta; British Columbia; Yukon Territory

Originator: Armitage, J.H., 1962.

Type Locality:
Peace River Area, in Texaco N.F.A. Buick Creek No. 7 well, in 6-26-8721W6M, 41.6 km (26 mi) northwest of Fort St. John, British Columbia, between 1,634 and 1,715 m (5,360 and 5,625 ft).

Distribution:
From a maximunn thickness of 190 to 364 m (623 to 1,194 ft) south of the Sukunka foothills the Doig Formation thins to 150 m (492 ft) in the subsurface basin, and ultimately to an erosional subcrop limit to the eastward, in western Alberta. The formation extends as a fan from 53 deg N in northwestern Alberta, through northeastern British Columbia to the Yukon, and east-west from the disturbed belt to the 6th meridian.

Lithology:
Mainly fine-grained, grey, argillaceous siltstone and dark calcareous shale. Numerous bitumen stained areas, and interbedded nodular phosphates increasing near base. Sand content increases in a north-northwesterly direction. Anomalously thicker, fine-grained, porous sands occur locally as 'bars' or 'channel' fills in the upper units of the formation.

Relationship:
The top of the Doig is taken at the base of the Halfway Formation and is defined by the higher radioactivity of the Doig lithologies compared to those of the Halfway. This contact is disconformable. The base of the formation is placed at the base of the phosphate pellet beds of the lower Black Shale Member, and is conformable with the underlying Montney Formation. At its erosional sub-crop limit the Doig may be overlain by Jurassic or Cretaceous beds. Laterally the Doig correlates to the lower part of the Llama Member of the Sulphur Mountain Formation of the southern Rocky Mountains and foothills, the Whistler Member of the Whitehorse Formation, and the Toad Formation.

Other Citations:
Armitage, 1962; A.S.P.G.. 1964; Hunt and Ratcliffe, 1959; Miall, 1976; Mothersill, 1968; Pelletier, 1960, 1961.

Source: CSPG Lexicon of Canadian Stratigraphy, Volume 4, western Canada, including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba; D.J. Glass (editor)
Contributor: C. Dawes
Entry Reviewed: Yes
Name Set: Lithostratigraphic Lexicon
LastChange: 05 Jul 2004