Type Locality:

Peace River Plains of west-central Alberta, with good sections on the Smoky, Spirit and Pouce Coupe rivers.

Distribution:

The Kaskapau Shale is 477 m (1,565 ft) thick near the Pouce Coupe River, thinning to 160 m (525 ft) on the Smoky River. The Bad Heart Sandstone ranges from 1.5 to 8 m (5 to 26 ft) thick. The Puskaskau is 200 m (656 ft) thick near Pouce Coupe and thins to 123 m (403 ft) in the Spirit River and Smoky River area. The gross thickening of the Smoky Group, from 290 m (951 ft) on the Smoky River to 677 m (2,221 ft) on the Pouce Coupe River continues in northeastern British Columbia to somewhat more than 1,100 m (3,608 ft) along the foothills. The Smoky Group is found throughout the Peace River area of Alberta and in northeastern British Columbia south of the Peace River.

Locality Data:

Thickness(m): Minimum 290, Maximum 677.

Lithology:

Marine, thinly bedded, dark silty shale with occasional ironstone and claystone nodules and thin bentonite streaks, divided into a lower shale units the Kaskapau Formation, a middle sandstone, the Bad Heart Formation and an upper shale unit, the Puskwaskau Formation carrying fewer concretions than the Kaskapau Formation. Extra sand tongues appear in beds transitional with the underlying Dunvegan Sandstone Formation, viz: the Doe Creek and Pouce Coupe sandstones along the Pouce Coupe River, and a somewhat higher sand, the Howard Creek Sandstone in the Spirit River area. In the Pouce Coupe area the Baytree Conglomerate is a coarse clastic member introduced on an incipient unconformity within the Kaskapau Formation, and approximately equivalent to the Cardium Formation of the foothills of Alberta. Where the Cardium Sandstone is present the term Kaskapau is confined to pre-Cardium beds and the shale between the Cardium and the Bad Heart sandstones is referred to as the Muskiki Formation. The Chinook Sandstone occurs in the upper Puskwaskau, marking the transition with the overlying Wapiti in the British Columbia-Alberta boundary region. An oolitic iron formation is developed within the Bad Heart interval in the Clear Hills region north of the Peace River.

Relationship:

The Smoky Group is conformable with the underlying Dunvegan Sandstone, and the basal part interfingers with the top of the Dunvegan Formation in northeastern British Columbia near the foothills. The basal Dunveganoceras Zone is missing south of Watino, Alberta, suggesting a local disconformity. The Smoky Group is conformably overlain by, and transitional to the Wapiti continental sequence. The Smoky Group is approximately equivalent to all but the lower portion of the Blackstone, Cardium, and Wapiabi formations of the Alberta Group of the foothills of Alberta, to the Lea Park and the upper pare of the Colorado Group above the base of the Second White Specks marker bed in the central and southern plains of Alberta to the upper portion of the Labiche Formation of northeastern Albertar and, in part to the Kotaneelee Formation of the Liard River area.

History:

"Smoky River Group" was originally used by Dawson (1881) to describe 107 m (350 ft) of nodular shales and sandstone along the Smoky River. The name was shortened to "Smoky Group" by Russell (1943) and McLearn and Henderson (1944).

Other Citations:

Dawson, 1881; Gleddie, 1944; McLearn, 1918, 1926; McLearn and Henderson, 1944; Russell, 1943; Rutherford, 1930; Stelck, 1962; Stelck and Wall, 1954, 1955; Stott, 1960; Wall, 1960.

References:

Dawson, G.M., 1881. Report on the exploration from Port Simpson on the Pacific Coast to Edmonton on the Saskatchewan River, Embracing a portion of the northern part of British Columbia and the Peace River country, with Maps 150 and 152; Geological Survey of Canada, Report of Progress 1879-1880, Part B, p. 1-77.

McLearn, F.H. and Henderson, J.F., 1944. Geology and oil prospects of the Lone Mountain area, British Columbia; Geological Survey of Canada, Paper 44-2.

Russell, L.S., 1943b. Sexsmith-Bison Lake, Alberta; Geological Survey of Canada, Prelim. Map.