Doig Formation
The Doig Formation is a geologic formation of middle Triassic age in the Western Canadian Sedimentary Basin. It takes the name from Doig River, a tributary of the Beatton River, and was first described in the Texaco N.F.A. Buick Creek No. 7 well by J.H. Armitage in 1962..
Lithology
The Doig Formation is composed of fine grained, grey argillaceous siltstone and dark calcareous shale.Phosphate nodules occur at the base of the formation. Anomalously thicker, porous sandstone channels and bars are present locally in the upper units of the formation. The formation has provided fossils of various species of conodonts; Magnigondolella alexanderi, M. cyri, M. julii, M. nebuchadnezzari, M. salomae, Neogondolella curva,
N. hastata, N. panlaurentia and N. ex gr. shoshonensis.
Distribution
The Doig Formation reaches a maximum thickness of in the Canadian Rockies foothills it thins towards the north and east. It occurs in the subsurface in north-western Alberta, north-eastern British Columbia and southern Yukon, from 53°N and 118°W to the Canadian Rockies.Relationship to other units
The Doig Formation is unconformably overlain by the Halfway Formation of the Schooler Creek Group; the contact is marked by a dolomitic bed and a chert and quartz conglomerate bed. To the west it is overlain by younger Jurassic beds. It conformably overlies the Montney Formation and the contact is marked by a phosphate pellet bed in the base of the Doig.The formation correlates with the lower Llama Member of the Sulphur Mountain Formation in the southern ranges of the Canadian Rockies, with the Whistler Member of the Whitehorse Formation in the Muskwa Ranges, and with the Toad Formation in the upper Liard River area.