The Banff Formation is a stratigraphical unit of

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, whe ...

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 The Western Canadian 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 ...

. It takes the name from the town of

Banff, Alberta Banff is a town within Banff National Park in Alberta, Canada. It is located in Alberta's Rockies along the Trans-Canada Highway, approximately west of Calgary and east of Lake Louise. At above Banff is the community with the second highest e ...

, and was first described on the north-west slope of

Mount Rundle Mount Rundle is a mountain in Canada's Banff National Park overlooking the towns of Banff and Canmore, Alberta. The Cree name was ''Waskahigan Watchi'' or house mountain. In 1858 John Palliser renamed the mountain after Reverend Robert Rundle ...

, near Banff by E.M. Kindle in 1924.Kindle, E.M., 1924b. Standard Paleozoic section of Rocky Mountains near Banff, Alberta; Pan-American Geologist, vol. 42, no. 2 (September), pp. 113-124.

Lithology

The Banff Formation is composed of

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...

and

marlstone Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. Marl makes up the lower part ...

in the base,

chert Chert () is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a prec ...

and

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

in the middle,

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

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 ...

and

at the top.

Distribution

The Banff Formation extends from the 49th parallel in southern

Alberta Alberta ( ) is one of the thirteen provinces and territories of Canada. It is part of Western Canada and is one of the three prairie provinces. Alberta is bordered by British Columbia to the west, Saskatchewan to the east, the Northwest Ter ...

and the

Kootenays The Kootenays or Kootenay ( ) is a region of southeastern British Columbia. It takes its name from the Kootenay River, which in turn was named for the Kutenai First Nations people. Boundaries The Kootenays are more or less defined by the Kootenay ...

region of

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

to north-eastern British Columbia,

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 cent ...

and the

District of Mackenzie The District of Mackenzie was a regional administrative district of Canada's Northwest Territories. The district consisted of the portion of the Northwest Territories directly north of British Columbia, Alberta, and Saskatchewan on Canada's main ...

in the

Northwest Territories The Northwest Territories (abbreviated ''NT'' or ''NWT''; french: Territoires du Nord-Ouest, formerly ''North-Western Territory'' and ''North-West Territories'' and namely shortened as ''Northwest Territory'') is a federal territory of Canada. ...

. In its southern area, the thickness ranges from in the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...

to in the sub-surface of the prairies. In the north, it ranges from in the

Peace River Country The Peace River Country (or Peace Country; french: Région de la Rivière-de-la-paix) is an aspen parkland region centring on the Peace River in Canada. It extends from northwestern Alberta to the Rocky Mountains in northeastern British Columbia, ...

to in northern Alberta. The age of the formation ranges from late

Famennian The Famennian is the latter of two faunal stages in the Late Devonian Epoch. The most recent estimate for its duration estimates that it lasted from around 371.1 million years ago to 359.3 million years ago. An earlier 2012 estimate, still used b ...

Tournaisian The Tournaisian is in the ICS geologic timescale the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. The Tournaisian age lasted from Ma to Ma. It is preceded by the Famennian (the uppermost stage ...

Relationship to other units

The Banff Formation is overlies the

Palliser Formation The Palliser Formation is a stratigraphic unit of Late Devonian (Famennian) age in the Western Canada Sedimentary Basin. It is a thick sequence of limestone and dolomitic limestone that is present in the Canadian Rockies and foothills of west ...

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 ...

, the

Wabamun Formation 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 betw ...

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 bordere ...

, the Exshaw Formation in

southern Alberta Southern Alberta is a region located in the Canadian province of Alberta. In 2004, the region's population was approximately 272,017.Fort Nelson area. It is overlain by the

Pekisko Formation The Rundle Group is a stratigraphical unit of Mississippian age in the Western Canadian Sedimentary Basin. It takes the name from Mount Rundle (itself taking the name from Robert Terrill Rundle), and was first described in outcrops at the north ...

and the Livingstone Formation in north-central and southern Alberta respectively, and it is followed by the Shunda Formation in north-eastern British Columbia. An

unconformity An unconformity is a buried erosional or non-depositional surface separating two rock masses or strata of different ages, indicating that sediment deposition was not continuous. In general, the older layer was exposed to erosion for an interval o ...

is observed between Banff and the Rundle Group in

outcrop An outcrop or rocky outcrop is a visible exposure of bedrock or ancient superficial deposits on the surface of the Earth. Features Outcrops do not cover the majority of the Earth's land surface because in most places the bedrock or superficial ...

. The Banff Formation is equivalent to the Lodgepole Formation in

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...

. It can be correlated with the

Besa River Formation The Besa River Formation is a stratigraphical unit of Devonian age in the Western Canadian Sedimentary Basin. It takes the name from Besa River, a tributary of the Prophet River, and was first described in outcrop near the Muskwa River, in th ...

in north-eastern British Columbia. In the southeastern

, part of the formation passes laterally into the

References

{{Authority control Geologic formations of Alberta Stratigraphy of British Columbia Devonian Alberta Devonian British Columbia Western Canadian Sedimentary Basin Carboniferous southern paleotropical deposits