The Woodbend 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 ...

Frasnian The Frasnian is one of two faunal stages in the Late Devonian Period. It lasted from million years ago to million years ago. It was preceded by the Givetian Stage and followed by the Famennian Stage. Major reef-building was under way during ...

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 was first described in the ''British American Pyrcz No. 1'' well by

Imperial Oil Imperial Oil Limited () is a Canadian petroleum company. It is Canada's second-largest integrated oil company. It is majority-owned by American oil company ExxonMobil, with a 69.6% ownership stake in the company. It is a producer of crude oil, ...

geological staff in 1950.

Lithology

The Formation is composed of crystalline and

dolomitized Dolomitization is a geological process where magnesium ions replace calcium ions in the mineral calcite, resulting in the formation of dolomite. Dolomitization conditions are present in Abu Dhabi, the Mediterranean Sea, and some Brazilian hype ...

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) ...

( Cooking Lake Formation) in off-reef areas,

bituminous Bitumen ( , ) is an immensely viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American English, the m ...

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 ...

and argillaceous limestone, detrital limestone (reef fallout),

stromatoporoid Stromatoporoidea is an extinct clade of sea sponges common in the fossil record from the Middle Ordovician to the Late Devonian.Stock, C.W. 2001, Stromatoporoidea, 1926–2000: ''Journal of Paleontology'', v. 75, p. 1079–1089. They can be cha ...

calcarenite Calcarenite is a type of limestone that is composed predominantly, more than 50 percent, of detrital (transported) sand-size (0.0625 to 2 mm in diameter), Carbonate rock, carbonate grains. The grains consist of sand-size grains of either cor ...

(

Duvernay Formation The Duvernay Formation is a stratigraphic unit of Frasnian Geochronology, age in the Western Canadian Sedimentary Basin. It was first described in well Anglo Canadian Beaverhill Lake No. 2 in Alberta Township System, LSD 11-11-50-17W4M by Imperi ...

), gray shale, argillaceous limestone, argillaceous dolomite, crystalline dolomite ( Ireton Formation). In reef build-ups, it consists of massive limestone and dolomite with porosity (

Leduc Formation The Leduc Formation is a stratigraphic unit of Late Devonian (Frasnian) age in the Western Canada Sedimentary Basin. It takes its name from the city of Leduc, and it was formally described from the B.A. Pyrz No. 1 well in central Alberta, between ...

Hydrocarbon production

Oil An oil is any nonpolar chemical substance that is composed primarily of hydrocarbons and is hydrophobic (does not mix with water) and lipophilic (mixes with other oils). Oils are usually flammable and surface active. Most oils are unsaturate ...

is produced from the

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 ...

since the early 1950s. Shale gas and liquids are extracted from the

using horizontal drilling and multi-stage

hydraulic fracturing Fracking (also known as hydraulic fracturing, fracing, hydrofracturing, or hydrofracking) is a well stimulation technique involving the fracturing of Formation (geology), formations in bedrock by a pressurized liquid. The process involves the ...

. Several project test the economic viability of extracting

bitumen Bitumen ( , ) is an immensely viscosity, viscous constituent of petroleum. Depending on its exact composition, it can be a sticky, black liquid or an apparently solid mass that behaves as a liquid over very large time scales. In American Engl ...

from the Grosmont Formation.

Distribution

The Woodbend Group reaches a maximum thickness of in

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 ...

(where

reef A reef is a ridge or shoal of rock, coral, or similar relatively stable material lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic component, abiotic (non-living) processes such as deposition (geol ...

s were developed), and has typical thickness of in southern and

. It extends laterally from north-eastern

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 ...

through

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 into southern

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

and southern

Manitoba Manitoba is a Provinces and territories of Canada, province of Canada at the Centre of Canada, longitudinal centre of the country. It is Canada's Population of Canada by province and territory, fifth-most populous province, with a population ...

. Reef build-ups range in size from small mounds to pinnacle

s and large

atoll An atoll () is a ring-shaped island, including a coral rim that encircles a lagoon. There may be coral islands or cays on the rim. Atolls are located in warm tropical or subtropical parts of the oceans and seas where corals can develop. Most ...

size reefs and bank developments.

Subdivisions

;Central Alberta In

the following formations are recognized, from top to bottom: ;Northeast Alberta In northeast Alberta the following formations are recognized, from top to bottom:

Relationship to other units

The Woodbend Group is conformably overlain by the Winterburn Group and conformably overlays the Beaverhill Lake Group. It is

transgressive Transgressive may mean: *Transgressive art, a name given to art forms that violate perceived boundaries *Transgressive fiction, a modern style in literature *Transgressive Records, a United Kingdom-based independent record label *Transgressive (l ...

in the

Peace River Arch Peace is a state of harmony in the absence of hostility and violence, and everything that discusses achieving human welfare through justice and peaceful conditions. In a societal sense, peace is commonly used to mean a lack of conflict (such a ...

and Tathlina uplift. Newer deposits rest on the Woodbend group upon an erosional surface in eastern

, south-central

and

. It is equivalent to the Birdbear Formation and Duperow Formation in northern

Montana Montana ( ) is a landlocked U.S. state, state in the Mountain states, Mountain West subregion of the Western United States. It is bordered by Idaho to the west, North Dakota to the east, South Dakota to the southeast, Wyoming to the south, an ...

, southern

and southwestern

, as well as parts of the Fort Simpson Formation and

Muskwa Formation The Muskwa Formation is a stratigraphic unit of Frasnian age in the Western Canadian Sedimentary Basin. It takes the name from Muskwa River, and was first described in the Western National Gas Fort Nelson a-95-J/94-J-10 well by F.F. Gray and J.R ...

of northeastern

and southern

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

, while it corresponds to the Tathlina Formation, Twin Falls Formation and

Hay River Formation The Hay River Formation is a geologic formation in Northwest Territories. It preserves fossils dating back to the Devonian period. See also * List of fossiliferous stratigraphic units in Northwest Territories This is a list of fossiliferous ...

in the

Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...

References

{{Western Canadian Sedimentary Basin, Northeast_Plains=yes, Northwest_Plains=yes, South AB=yes Devonian Alberta Devonian British Columbia Devonian Saskatchewan Devonian Manitoba Devonian Northwest Territories Western Canadian Sedimentary Basin Devonian System of North America Geologic groups of Alberta Geologic groups of British Columbia Geologic groups of Saskatchewan Geologic groups of Manitoba Geologic groups of the Northwest Territories Devonian southern paleotropical deposits Frasnian Stage Geologic groups of Yukon Limestone groups of Canada Dolomite formations of Canada Shale groups of Canada