Alberta Group | |
---|---|
Stratigraphic range: | |
Type | Geological formation |
Sub-units | Wapiabi Formation, Chungo Member, Cardium Formation, Blackstone Formation, Jumping Pound Member |
Underlies | Belly River Formation |
Overlies | Blairmore Group, Luscar Group, Crowsnest Formation |
Thickness | up to 1,219 feet (370 m) [1] |
Lithology | |
Primary | Shale, sandstone |
Other | Siltstone, siderite, limestone |
Location | |
Region | Alberta |
Country | Canada |
Type section | |
Named for | Alberta |
Named by | G.S. Hume, 1930 |
The Alberta Group is a stratigraphical unit of Cenomanian to early Campanian age in the Lewis overthrust in the Western Canadian Sedimentary Basin. [2]
It takes the name from the province of Alberta, and was first described in outcrops along the Highwood River in southern Alberta by G.S. Hume in 1930. [3]
The Alberta Group is composed of silty shale for the most part. Two thick shale deposits (Blackstone Formation and Wapiabi Formation) are present above and below a sandstone sequence (the Cardium Formation). Sideritic concretions and thin argillaceous limestone beds are present within the shale stacks. [1]
Gas is produced from the Cardium Formation in Yellowhead County.
The Alberta Group occurs along the Canadian Rockies foothills from the United States-Canada border to the Athabasca River. In its type locality along the Highwood River in Southern Alberta, the group has a thickness of 610 feet (190 m). It reaches a maximum of 1,219 feet (370 m) north of the North Saskatchewan River. [1]
The Alberta Group is conformably overlain by the Belly River Formation and rests unconformably on deposits of the Blairmore Group and Luscar Group in the Canadian Rockies foothills and on the volcanic Crowsnest Formation in southern Alberta's west. The group is equivalent with the Colorado Group and Lea Park Formation in southern Alberta's prairies, and with the Smoky Group in northern Alberta and north-east British Columbia. [1]
The Wapiabi Formation is equivalent to the upper Colorado Group shales and Lea Park Formation in central Alberta and the sum of Puskwaskau Formation, Bad Heart Formation and Muskiki Formation in the west part of northern Alberta. [4]
The Alberta Group has the following sub-divisions from top to base:
Sub-unit | Age | Lithology | Max Thickness | Reference |
---|---|---|---|---|
Wapiabi Formation | Campanian | marine shale, which sideritic concretions, siltstone, sandstone and limestone *contains the Chungo Member sandstone | 640 m (2,100 ft) | [4] |
Cardium Formation | Turonian to Coniacian | marine sandstone | 108 m (350 ft) | [5] |
Blackstone Formation | Cenomanian to Turonian | marine shale and siltstone with minor limestone, sandstone and bentonite *contains the Jumping Pound Member sandstone | 426 m (1,400 ft) | [6] |
The Kaskapau Formation is a geological formation in North America whose strata date back to the Late Cretaceous.
The Belly River Group is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.
The Nikanassin Formation is a stratigraphic unit of Late Jurassic (Portlandian) to Early Cretaceous (Barremian) age. It is present along the western edge of the Western Canada Sedimentary Basin in western Alberta and northeastern British Columbia. Its name was first proposed by D.B. Dowling in 1909 (Coal Fields South of Grand Trunk Pacific Railway, in the foothills of the Rocky Mountain, Alberta Page 140 paragraph 4 " to this it is proposed to give the name Nikanassin, from the Cree word meaning outer range" Also it is noted on the map by D.B. Dowling.(Geological Survey of Canada. Incorrect info follows: It was named by B.R. MacKay in 1929 for the Nikanassin Range of the front-central ranges of the Canadian Rockies. Mackay did not designate a type locality for the formation, although he described outcrops near the hamlet of Brûlé, north of the Yellowhead Highway outside of Jasper National Park.
Gething Formation is a stratigraphic unit of Lower Cretaceous (Aptian) age in the Western Canada Sedimentary Basin. It is present in northeastern British Columbia and western Alberta, and includes economically important coal deposits.
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 present. It was first described along the Bow River banks by James Hector in 1895. It is present throughout western Alberta and in northeastern British Columbia, and it is a major source of petroleum and natural gas.
Bullhead Group is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin of northeastern British Columbia and western Alberta. It was first defined by F.H. McLearn in 1918 as the Bullhead Mountain Formation, but later was upgraded to group status. It consists of the Cadomin and Gething Formations, although some early workers included the Bluesky Formation and others in the group.
The Fernie Formation is a stratigraphic unit of Jurassic age. It is present in the western part of the Western Canada Sedimentary Basin in western Alberta and northeastern British Columbia. It takes its name from the town of Fernie, British Columbia, and was first defined by W.W. Leach in 1914.
The Fort St. John Group is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the city of Fort St. John, British Columbia and was first defined by George Mercer Dawson in 1881.
The Peace River Formation is a stratigraphical unit of middle Albian age in the Western Canadian Sedimentary Basin.
The Smoky Group is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.
The Dunvegan Formation is a stratigraphical unit of Cenomanian age in the Western Canadian Sedimentary Basin.
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 for their importance in Eastern Colorado. The surface outcrop of this group produces distinctive landforms bordering the Great Plains and it is a significant feature of the subsurface of the Denver Basin and the Western Canadian Sedimentary Basin. These formations record important sequences of the Western Interior Seaway. As the geology of this seaway was studied, this name came to be used in states beyond Colorado but later was replaced in several of these states with more localized names.
The Mannville Group is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.
The Exshaw Formation is a stratigraphic unit in the Western Canada Sedimentary Basin. It takes the name from the hamlet of Exshaw, Alberta in the Canadian Rockies, and was first described from outcrops on the banks of Jura Creek north of Exshaw by P.S. Warren in 1937. The formation is of Late Devonian to Early Mississippian age as determined by conodont biostratigraphy, and it straddles the Devonian-Carboniferous boundary.
The Muskiki Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.
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..
The Lea Park Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin, Canada.
The Joli Fou Formation is a allostratigraphical unit of middle Albian age in the Western Canadian Sedimentary Basin. It takes the name from the Joli Fou Rapids on the Athabasca River, and was first described in an outcrop along the river, 8 kilometers (5.0 mi) downstream from Joli Fou Rapids, by RTD Wickenden in 1949.
The Ellis Group is a stratigraphical unit of Bajocian-Oxfordian age in Alberta, Saskatchewan, Montana and Wyoming in the Western Canadian Sedimentary Basin. It takes the name from Fort Ellis, Montana, and was first described in outcrop in the Rocky Creek Canyon by A.C. Peale in 1893.
The geology of Alberta encompasses parts of the Canadian Rockies and thick sedimentary sequences, bearing coal, oil and natural gas, atop complex Precambrian crystalline basement rock.