The Alberta 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 ...

Cenomanian The Cenomanian is, in the International Commission on Stratigraphy's (ICS) geological timescale, the oldest or earliest age (geology), age of the Late Cretaceous epoch (geology), Epoch or the lowest stage (stratigraphy), stage of the Upper Cretace ...

to early

Campanian The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campa ...

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

Lewis overthrust The Lewis Overthrust is a geologic thrust fault structure of the Rocky Mountains found within the bordering national parks of Glacier in Montana, United States and Waterton Lakes in Alberta, Canada. The structure was created due to the collision o ...

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 province of

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

, and was first described in outcrops along the

Highwood River The Highwood River is a tributary of the Bow River in southwestern Alberta, Canada. Course The Highwood originates in the Canadian Rockies in Peter Lougheed Provincial Park, in the Highwood Pass below Mount Arethusa. It flows south and is paral ...

southern Alberta Southern Alberta is a region located in the Canadian province of Alberta. In 2016, the region's population was approximately 291,112. The primary cities are Lethbridge and Medicine Hat. The region is known mostly for agricultural production, but o ...

by G.S. Hume in 1930.Hume, G.S., 1930. The Highwood-Jumpingpound Anticline, with Notes on Turner Valley, New Black Diamond and Priddis Valley Structures, Alberta;

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 ...

, Summary Report 1929, Part B, pp. 1-24.

Lithology

The Alberta Group is composed of 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 ...

for the most part. Two thick

deposits (Blackstone Formation and Wapiabi Formation) are present above and below a

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 ...

sequence (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 ...

). Sideritic concretions and thin argillaceous

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

beds are present within the shale stacks.

Oil/gas 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

Yellowhead County Yellowhead County is a municipal district in west central Alberta, Canada. It is the only municipal district within Alberta census division No. 14. History *1994: Established as a ''Municipal District of Yellowhead No. 94'' on January 1. ...

Distribution

The Alberta Group occurs along 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 from the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

border to the

Athabasca River The Athabasca River (French: ''Rivière Athabasca'') in Alberta, Canada, originates at the Columbia Icefield in Jasper National Park and flows more than before emptying into Lake Athabasca. Much of the land along its banks is protected in nationa ...

. In its type locality along the

Southern Alberta Southern Alberta is a region located in the Canadian province of Alberta. In 2016, the region's population was approximately 291,112. The primary cities are Lethbridge and Medicine Hat. The region is known mostly for agricultural production, but o ...

, the group has a thickness of . It reaches a maximum of north of the

North Saskatchewan River The North Saskatchewan River is a glacier-fed river that flows from the Canadian Rockies continental divide east to central Saskatchewan, where it joins with the South Saskatchewan River to make up the Saskatchewan River. Its water flows event ...

Relationship to other units

The Alberta Group is conformably overlain by the

Belly River Formation The Belly River Group is a stratigraphic unit of Late Cretaceous age in the Western Canadian Sedimentary Basin. It takes the name from the Belly River, a tributary of the Oldman River in southern Alberta, and was first described in outcrop on t ...

and rests

unconformably An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval o ...

on deposits of the

Blairmore Group The Blairmore Group, originally named the Blairmore Formation, is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in southwestern Alberta and southeastern British Columbia. It is subdivided into fo ...

and

Luscar Group The Luscar Group is a geologic unit of Early Cretaceous age in the Western Canadian Sedimentary Basin, Western Canada Sedimentary Basin that is present in the foothills of southwestern Alberta. It is subdivided into a series of formation (stratigr ...

in the

foothills and on the volcanic

Crowsnest Formation The Crowsnest Formation, also called the Crowsnest Volcanics, is a geological formation in southwestern Alberta, Canada, on the southwestern margin of the Western Canadian Sedimentary Basin, Western Canada Sedimentary Basin. It was named for the Cr ...

's west. The group is equivalent with the

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 ...

and Lea Park Formation in southern Alberta's prairies, and with the

Smoky Group The Smoky Group is a stratigraphic unit of Late Cretaceous 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 and Pouce Coupe ...

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 ...

and north-east

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 ...

. The Wapiabi Formation is equivalent to the upper

shales and Lea Park Formation 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 the sum of

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 ...

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 ...

and Muskiki Formation in the west part of

Subdivisions

The Alberta Group has the following sub-divisions from top to base:

References

{{Western Canadian Sedimentary Basin, Canadian Rockies=yes Geologic groups of Alberta Cretaceous Alberta Shale groups of Canada Sandstone groups of Canada Siltstone groups Limestone groups of Canada