Bullhead Group

Last updated
Bullhead Group
Stratigraphic range: Barremian–Albian
Type Geological formation
Sub-units Gething Formation
Cadomin Formation
Underlies Fort St. John Group
Overlies Nikanassin Formation, Fernie Group, Minnes Group, Kootenay Group
Thicknessup to 900 metres (2,950 ft) [1]
Lithology
Primary Conglomerate, sandstone, siltstone and mudstone
Other Coal
Location
Coordinates 56°01′N122°08′W / 56.01°N 122.14°W / 56.01; -122.14 (Bullhead Group)
RegionFlag of British Columbia.svg  British Columbia
Flag of Alberta.svg  Alberta
CountryFlag of Canada (Pantone).svg  Canada
Type section
Named byF.H. McLearn [2]

Bullhead Group is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin of northeastern British Columbia and western Alberta. [3] It was first defined by F.H. McLearn in 1918 as the Bullhead Mountain Formation, [2] 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. [4]

Contents

Lithology

Bullhead Group includes the conglomerate and quartzose sandstones of the Cadomin Formation at the base, and grades to sandstone, siltstone, mudstone, shale and coal seams of the overlying Gething Formation. Those sediments were deposited in alluvial fan, braided river, deltaic and coastal plain environments. [4]

Distribution

The Bullhead Group is present in the foothills of the Northern Rocky Mountains and the adjacent plains, extending from the Tuchodi River of British Columbia in the north to the Smoky River of Alberta in the south. It thins eastward from about 900 meters (3,000 ft) in the western foothills of northeastern British Columbia to about 100 meters (330 ft) in the Peace River plains, reaching zero near Fort St. John. The most complete section is found in the type locality of the Gething Formation in the Peace River Canyon immediately downstream from the W. A. C. Bennett Dam. [1]

Relationship to other units

The Bullhead Group overlies a major regional unconformity caused by pre-Bullhead erosion. [4] It rests unconformably on the Fernie Formation, the Nikanassin Formation, the Minnes Group or the Kootenay Group, depending on the location and the extent of the erosion. It is overlain conformably by the glauconitic sandstones and marine shales at the base of the Fort St. John Group. [1]

Related Research Articles

<span class="mw-page-title-main">Nikanassin Formation</span>

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.

<span class="mw-page-title-main">Cadomin Formation</span>

The Cadomin Formation is a stratigraphic unit of Early Cretaceous age in the western part of the Western Canada Sedimentary Basin. It is extends from southeastern British Columbia through western Alberta to northeastern British Columbia, and it contains significant reservoirs of natural gas in some areas. It was named after the mining town of Cadomin, which is an acronym of "Canadian Dominion Mining".

<span class="mw-page-title-main">Bluesky Formation</span>

The Bluesky Formation is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the hamlet of Bluesky, and was first described in Shell's Bluesky No. 1 well by Badgley in 1952.

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.

<span class="mw-page-title-main">Cardium Formation</span> Stratigraphic range in western Canada

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.

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.

<span class="mw-page-title-main">Dunvegan Formation</span> Stratigraphical unit in the Western Canadian Sedimentary Basin

The Dunvegan Formation is a stratigraphical unit of Cenomanian age in the Western Canadian Sedimentary Basin.

The Schooler Creek Group is a stratigraphic unit of Middle to Late Triassic age in the Western Canadian Sedimentary Basin. It is present in northeastern British Columbia. It was named for Schooler Creek, a left tributary of Williston Lake, and was first described in two oil wells northwest of Fort St. John, by F.H. McLearn in 1921. Exposures along Williston Lake serve as a type locality in outcrop.

The Mist Mountain Formation is a geologic formation of latest Jurassic to earliest Cretaceous age in the Western Canada Sedimentary Basin that is present in the southern and central Canadian Rockies. It was named for outcrops along the western spur of Mist Mountain in Alberta by D.W. Gibson in 1979. The Mist Mountain Formation contains economically important coal seams that have been mined in southeastern British Columbia and southwestern Alberta.

<span class="mw-page-title-main">Edmonton Group</span> Stratigraphic unit in central Alberta, Canada

Within the earth science of geology, the Edmonton Group is a Late Cretaceous to early Paleocene stratigraphic unit of the Western Canada Sedimentary Basin in the central Alberta plains. It was first described as the Edmonton Formation by Joseph Burr Tyrrell in 1887 based on outcrops along the North Saskatchewan River in and near the city of Edmonton. E.J.W. Irish later elevated the formation to group status and it was subdivided into four separate formations. In ascending order, they are the Horseshoe Canyon, Whitemud, Battle and Scollard Formations. The Cretaceous-Paleogene boundary occurs within the Scollard Formation, based on dinosaurian and microfloral evidence, as well as the presence of the terminal Cretaceous iridium anomaly.

The Elk Formation is a stratigraphic unit of the Western Canada Sedimentary Basin that is present in southeastern British Columbia and southwestern Alberta. It is probably of Early Cretaceous age, but in some areas its strata could be as old as Late Jurassic. It includes minor thin coal beds and was named for outcrops near the now-abandoned Elk River coal mine east of Fernie, British Columbia.

The Minnes Group, originally named the Minnes Formation, is a geologic unit of latest Jurassic to earliest Cretaceous age in the Western Canada Sedimentary Basin. It is present in the northern foothills of the Canadian Rockies and the adjacent plains in northeastern British Columbia and west-central Alberta. Its strata include natural gas reservoirs and minor coal deposits. Fossil dinosaur tracks have been described from one of its formations.

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 four formations: Cadomin Formation, Gladstone, Beaver Mines and Ma Butte, all of which are defined by type sections, most of which contain plant fossils. In some areas the Blairmore contains significant reservoirs of natural gas.

The Monach Formation is a geologic formation of Early Cretaceous (Valanginian) age in the Western Canada Sedimentary Basin that consists primarily of sandstone. It is present in the northern foothills of the Canadian Rockies and the adjacent plains in northeastern British Columbia.

The Hulcross Formation is a geologic formation in the Western Canada Sedimentary Basin in northeastern British Columbia that was deposited in marine environments during the late Albian stage of the Early Cretaceous period. At one time considered to be a member of the Commotion Formation, it was elevated to formation status by D.F. Stott in 1982. It preserves ammonites and other fossils.

The Boulder Creek Formation is a geologic formation in northeastern British Columbia. It was named for a tributary to Commotion Creek in the Pine Pass area by E.M. Spieker in 1921. At one time considered to be a member of the Commotion Formation, it was elevated to formation status by D.F. Stott in 1982.

The Gorman Creek Formation is a geologic formation of Early Cretaceous (Valanginian) age in the Western Canada Sedimentary Basin that consists primarily of nonmarine sediments. It is present in the northern foothills of the Canadian Rockies and the adjacent plains in northeastern British Columbia. Plant fossils and dinosaur tracks have been described from its strata.

The Bickford Formation is a geologic formation of Early Cretaceous (Valanginian) age in the Western Canada Sedimentary Basin that consists primarily of nonmarine sediments. It is present in the northern foothills of the Canadian Rockies in northeastern British Columbia.

The Luscar Group is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in the foothills of southwestern Alberta. It is subdivided into a series of formations, some of which contain economically significant coal deposits that have been mined near Cadomin and Luscar. Coal mining in those areas began in the early 1900s and continues near Luscar as of 2016.

The Gladstone Formation is a stratigraphic unit of Early Cretaceous (Aptian) age in the Western Canada Sedimentary Basin. It is present in the foothills of southwestern Alberta and is named for outcrops along Gladstone Creek, a tributary of the Castle River south of the Crowsnest Pass.

References

  1. 1 2 3 Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. ISBN   0-920230-23-7.
  2. 1 2 McLearn, F.H., 1923. Peace River Canyon Coal Area, British Columbia; Geological Survey of Canada, Summary Report 1922, Part B, pp. 1-46.
  3. Canadian Society of Petroleum Geologists and Alberta Geological Survey (1994). "The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 19: Cretaceous Mannville Group of the Western Canada Sedimentary Basin". Compiled by Mossop, G.D. and Shetsen, I. Archived from the original on 2016-07-01. Retrieved 2016-06-20.
  4. 1 2 3 Stott, D.F. 1965. Lower Cretaceous Bullhead and Fort St John Groups, between Smoky and Peace Rivers, Rocky Mountain foothills, Alberta and British Columbia. Geological Survey of Canada, Bulletin 152, 279 p. ISBN   0-660-10208-0.