The Winterburn Group is a

stratigraphical Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostrati ...

unit of

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 th ...

age Age or AGE may refer to: Time and its effects * Age, the amount of time someone or something has been alive or 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. It takes the name from Winterburn area located west of Edmonton, and was first described in well ''P.A. Pyrcz No. 1'' by

Imperial Oil Limited Imperial Oil Limited (French: ''Compagnie Pétrolière Impériale Ltée'') is a Canadian petroleum company. It is Canada's second-biggest integrated oil company. It is majority owned by American oil company ExxonMobil with around 69.6 percent o ...

in 1950.Geological Staff, Imperial Oil Limited, Western Division, 1950. Devonian Nomenclature in Edmonton Area, Alberta, Canada. Bulletin of the

American Association of Petroleum Geologists The American Association of Petroleum Geologists (AAPG) is one of the world's largest professional geological societies with more than 40,000 members across 129 countries as of 2021. The AAPG works to "advance the science of geology, especially as ...

, Vol. 34, No. 9, pp. 1807-1825.

Lithology

The Winterburn Group is composed of silty

dolomite Dolomite may refer to: *Dolomite (mineral), a carbonate mineral *Dolomite (rock), also known as dolostone, a sedimentary carbonate rock *Dolomite, Alabama, United States, an unincorporated community *Dolomite, California, United States, an unincor ...

, evaporite, argillaceous limestone, red and green

siltstone Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt. It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility.Blatt ''et al.'' 1980, p ...

, anhydrite, silty

and

. Pinnacle reefs develop in the Nisku Formation.

Hydrocarbon production

Oil is produced from the Nisku Formation in the Pembina oil field.

Distribution

The Winterburn Group reaches a maximum thickness of west of the Leduc reef system. In central Alberta it is 30 to 70m thick. It thins out over the

Peace River Arch Peace is a concept of societal friendship and harmony in the absence of hostility and violence. In a social sense, peace is commonly used to mean a lack of conflict (such as war) and freedom from fear of violence between individuals or groups. ...

, and disappears in north-eastern British Columbia.

Subdivisions

The Winterburn Group is composed, from bottom to top, of the Nisku, Calmar and Graminia Formations. The Graminia Formation includes the carbonate Blue Ridge Member west of the Rimbey-Meadowbrook reef trend.

Relationship to other units

The Winterburn Group is conformably overlain by the

Wabamun Group The Wabamun Formation is a stratigraphic unit of Late Devonian (Famennian) age in the Western Canada Sedimentary Basin. It takes the name from Wabamun Lake and was first described in the ''Anglo Canadian Wabamun Lake No. 1'' well (located between ...

and overlays the Ireton Formation, except in the Peace River Arch, where it rests on the

Precambrian The Precambrian (or Pre-Cambrian, sometimes abbreviated pꞒ, or Cryptozoic) is the earliest part of Earth's history, set before the current Phanerozoic Eon. The Precambrian is so named because it preceded the Cambrian, the first period of the ...

basement A basement or cellar is one or more floors of a building that are completely or partly below the ground floor. It generally is used as a utility space for a building, where such items as the furnace, water heater, breaker panel or fuse box, ...

. It is correlated with the Birdbear Formation and part of the Three Forks Group in Saskatchewan, with the Southesk Formation and

Alexo Formation The Alexo Formation a stratigraphic unit of Late Devonian (late Frasnian to early Famennian) age. It is present on the western edge of the Western Canada Sedimentary Basin in the central Rocky Mountains and foothills of Alberta. The formation cons ...

in the

Canadian Rockies The Canadian Rockies (french: Rocheuses canadiennes) 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 ...

and with the

Redknife Formation The Redknife Formation is a stratigraphical unit of Devonian age in the Western Canadian Sedimentary Basin. It takes the name from Redknife River, a tributary of the Mackenzie River, and was first described in the banks of the Trout River, nor ...

and

Kakisa Formation The Kakisa Formation is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin. It takes the name from the Kakisa River, a tributary of the Mackenzie River, and was first described in outcrop on the banks of the Trout ...

in north-eastern British Columbia.

References

{{Western Canadian Sedimentary Basin, Northeast_Plains=yes, Northwest_Plains=yes, Central_Plains=yes Stratigraphy of Alberta Devonian southern paleotropical deposits