The Smoky Group is a

stratigraphic unit A stratigraphic unit is a volume of rock of identifiable origin and relative age range that is defined by the distinctive and dominant, easily mapped and recognizable petrographic, lithologic or paleontologic features ( facies) that characteriz ...

of Late Cretaceous

age Age or AGE may refer to: Time and its effects * Age, the amount of time someone has been alive or something has existed ** East Asian age reckoning, an Asian system of marking age starting at 1 * Ageing or aging, the process of becoming older ...

in the

Western Canadian Sedimentary Basin The Western Canada Sedimentary Basin (WCSB) underlies of Western Canada including southwestern Manitoba, southern Saskatchewan, Alberta, northeastern British Columbia and the southwest corner of the Northwest Territories. This vast sedimentary b ...

. It takes the name from the

Smoky River The Smoky River is a river in western Alberta, Canada. It is a major tributary of the Peace River (Canada), Peace River. The name refers to the presence of "smouldering beds of coal in the riverbank" noted by the Cree people, an Indigenous peop ...

and was first described in outcrops along the banks of the Smoky River, Spirit River and

Pouce Coupe River The Pouce Coupe River is a major tributary of the Peace River (Canada), Peace River in Alberta and British Columbia, Canada. Its name is officially spelled ''Pouce Coupé River'', but it is commonly written without the acute accent. Originating i ...

s by

George Mercer Dawson George Mercer Dawson (August 1, 1849 – March 2, 1901) was a Canadian geologist and surveyor. He performed many early explorations in western North America and compiled numerous records of the native peoples. Biography He was born in ...

in 1881.Dawson, G.M., 1881. Report on the exploration from Port Simpson on the Pacific Coast to Edmonton on the North 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 The Geological Survey of Canada (GSC; , CGC) is a Canadian federal government agency responsible for performing geological surveys of the country developing Canada's natural resources and protecting the environment. A branch of the Earth Science ...

, Report of Progress 1879-1880, Part B, p. 1-77.

Lithology

The Smoky Group is represented by marine silty

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...

with

ironstone Ironstone is a sedimentary rock, either deposited directly as a ferruginous sediment or created by chemical replacement, that contains a substantial proportion of an iron ore compound from which iron (Fe) can be smelted commercially. Not to be c ...

and

bentonite Bentonite ( ) is an Absorption (chemistry), absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelli ...

streaks.

Sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

occurs at the base and is transitional to the Dunvegan Formation.

Hydrocarbon production

Gas Gas is a state of matter that has neither a fixed volume nor a fixed shape and is a compressible fluid. A ''pure gas'' is made up of individual atoms (e.g. a noble gas like neon) or molecules of either a single type of atom ( elements such as ...

is produced from the

Cardium Formation The Cardium Formation is a stratigraphic unit of Late Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the fossilized heart-shaped cockle shells in the family Cardiidae (from Greek ''kardiā'', "heart") present. It ...

in the southern reaches of the Group, in

central Alberta Central Alberta is a region located in the Canadian province of Alberta. Central Alberta is the most densely populated rural area in the province. Agriculture and energy are important to the area's economy. Geography Central Alberta is bordered ...

and

northern Alberta Northern Alberta is a geographic region located in the Canadian province of Alberta. An informally defined cultural region, the boundaries of Northern Alberta are not fixed. Under some schemes, the region encompasses everything north of the ce ...

Distribution

The Kaskapau Shale reaches 477m in the

area and thins towards the east in the

area. The

Bad Heart Formation The Smoky Group is a stratigraphic unit of Late Cretaceous Geochronology, age in the Western Canadian Sedimentary Basin. It takes the name from the Smoky River and was first described in outcrops along the banks of the Smoky River, Spirit River a ...

sandstone is up to 8m thick, while the

Puskwaskau Formation The Smoky Group is a stratigraphic unit of Late Cretaceous Geochronology, age in the Western Canadian Sedimentary Basin. It takes the name from the Smoky River and was first described in outcrops along the banks of the Smoky River, Spirit River a ...

ranges from 200m in the Pouce Coupe Prairie to 123m in the Spirit River area. The entire group measures up to in the Pouce Coupe Prairie and can reach in the

Canadian Rockies The Canadian Rockies () or Canadian Rocky Mountains, comprising both the Alberta Rockies and the British Columbian Rockies, is the Canadian segment of the North American Rocky Mountains. It is the easternmost part of the Canadian Cordillera, w ...

foothills of northeast

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

Relationship to other units

The Smoky Group is conformably and transgressively followed by the Wapiti Group and rests conformably on the Dunvegan Formation sandstone. The Cardium sandstone and Muskiki shale are replacing the upper parts of the

Kaskapau Formation The Kaskapau Formation is a geological formation in North America whose strata date back to the Late Cretaceous. The name derives from ''kaskapahtew'' (ᑲᐢᑲᐸᐦᑌᐤ), the Cree word for "smoky". It was first described on the banks of the ...

in the south-east of the distribution area. The entire group correlates with the Blackstone Formation,

and

Wapiabi Formation The Alberta Group is a stratigraphic unit of Cenomanian to early Campanian Geochronology, age in the Lewis Overthrust, Lewis overthrust in the Western Canadian Sedimentary Basin. It takes the name from the province of Alberta, and was first descr ...

of the Alberta Group in the southern foothills. The equivalent stratigraphic sequence in

consists of the Lea Park Formation and the upper

Colorado Group Colorado is a geologic name applied to certain rocks of Cretaceous age in the North America, particularly in the western Great Plains. This name was originally applied to classify a group of specific marine formations of shale and chalk known ...

, in north-eastern Alberta it correlates with Labiche Formation, and with the Kotaneelee Formation in the

Liard River The Liard River of the Boreal forest of Canada, North American boreal forest flows through Yukon, British Columbia and the Northwest Territories, Canada. Rising in the Saint Cyr Range of the Pelly Mountains in southeastern Yukon, it flows sout ...

area.

Subdivisions

The Smoky Group has the following sub-divisions from top to bottom: The Kaskapau Formation is equivalent to the sum of Blackstone Formation,

and Muskiki Formation. File:Paskwaskau.JPG, Paskwaskau Shale File:Badheart Sand.JPG, Bad Heart Sandstone File:Kaskapau Shale.JPG, Kaskapau Shale

References

{{WCSB, Northwest_Plains=yes Geologic groups of Alberta Geologic groups of British Columbia Cretaceous Alberta Cretaceous British Columbia Shale groups of Canada Sandstone groups of Canada Siltstone groups