The Winterburn 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 ...
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 ...
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 takes the name from Winterburn area located west of
Edmonton
Edmonton is the capital city of the Provinces and territories of Canada, Canadian province of Alberta. It is situated on the North Saskatchewan River and is the centre of the Edmonton Metropolitan Region, which is surrounded by Central Alberta ...
, and was first described in well ''P.A. Pyrcz No. 1'' by
Imperial Oil Limited 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 about 17,000 members across 129 countries. The AAPG works to "advance the science of geology, especially as it relates to ...
, Vol. 34, No. 9, pp. 1807-1825.
Lithology
The Winterburn Group is composed of silty
dolomite,
evaporite
An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as oce ...
, 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) ...
, 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.
Although its permeabil ...
,
anhydrite
Anhydrite, or anhydrous calcium sulfate, is a mineral with the chemical formula CaSO4. It is in the orthorhombic crystal system, with three directions of perfect cleavage parallel to the three planes of symmetry. It is not isomorphous with the ...
, silty
dolomite and
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.
Although its permeabil ...
. Pinnacle
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 develop in the Nisku Formation.
[
]
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 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
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 ...
it is 30 to 70m thick. It thins out over 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 disappears in 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 ...
.
[
]
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
Rimbey is a town in central Alberta, Canada. It is located at the junction of Alberta Highway 20, Highways 20 and Alberta Highway 53, 53 in the Blindman River valley area approximately northwest of Red Deer, Alberta, Red Deer and southwest of ...
-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 pC, 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 t ...
basement
A basement is any Storey, floor of a building that is not above the grade plane. Especially in residential buildings, it often is used as a utility space for a building, where such items as the Furnace (house heating), furnace, water heating, ...
.[
It is correlated with the ]Birdbear Formation
The Saskatchewan Group is a stratigraphical unit of Frasnian age in the Western Canadian Sedimentary Basin.
It takes the name from the province of Saskatchewan, and was first described in the ''Mobil Oil Woodley Sinclair Cantuar X-2-21'' well by ...
and part of the Three Forks Group
The Three Forks Group is a stratigraphic unit of Famennian age in the Williston Basin.
It takes the name from the city of Three Forks, Montana, and was first described in outcrop near the city by A.C. Peale in 1893 (for the Three Forks Shale).
L ...
in 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 ...
, with the Southesk Formation and Alexo Formation in 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 ...
and with the Redknife Formation and Kakisa Formation in 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 ...
.
References
{{Western Canadian Sedimentary Basin, Northeast_Plains=yes, Northwest_Plains=yes, Central_Plains=yes
Devonian southern paleotropical deposits
Geologic groups of Alberta
Devonian Alberta
Dolomite groups
Limestone groups of Canada
Siltstone groups
Shale groups of Canada