The Slave Point Formation 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 ...

Middle Devonian In the geological timescale, the Middle Devonian epoch (from 393.3 ± 1.2 million years ago to 382.7 ± 1.6 million years ago) occurred during the Devonian period, after the end of the Emsian age. The Middle Devonian epoch is subdivided into two ...

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 Slave Point, a promontory on the north-west shore of the

Great Slave Lake Great Slave Lake is the second-largest lake in the Northwest Territories, Canada (after Great Bear Lake), List of lakes by depth, the deepest lake in North America at , and the List of lakes by area, tenth-largest lake in the world by area. It ...

, and was first described in outcrop on the southern shore of the lake and along the Buffalo River by A.E. Cameron in 1918. It was subsequently defined in the subsurface by J. Law in 1955,Law, James, 1955. Geology of northwestern Alberta and adjacent areas;

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 ...

(AAPG), Bulletin of the AAPG, vol. 39, no. 10 (October), pp. 1927-1975. based on

lithology The lithology of a rock unit is a description of its physical characteristics visible at outcrop, in hand or core samples, or with low magnification microscopy. Physical characteristics include colour, texture, grain size, and composition. Lit ...

encountered in the ''California Standard Steen River 2-22-117-5W6M'' well in

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 ...

Lithology

The Slave Point Formation is composed of brown

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) ...

, crystalline dolomite and

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 ...

laminae. It contains

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 ...

s 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 ...

and southern

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 ...

and 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 ...

Distribution

The Slave Point Formation has a thickness ranging from to . It occurs in southern

, northeastern

and

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 ...

Relationship to other units

The Slave Point Formation is

unconformably 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 ...

overlain by the Beaverhill Lake Group or

Waterways Formation The Beaverhill Lake Group is a geologic unit of Middle Devonian to Late Devonian (late Givetian to Frasnian) age in the Western Canada Sedimentary Basin that is present in the southwestern Northwest Territories, northeastern British Columbia an ...

and by the Otter Park Member or

Muskwa Member 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 the

Horn River Formation The Horn River Formation (also ''Horn River Shale'') is a stratigraphic unit of Devonian (early Givetian to late Frasnian) age in the Western Canadian Sedimentary Basin. It is a thick sequence of marine sediments that was first described in outc ...

in north-eastern British Columbia. It conformably overlays the Fort Vermilion Formation (or is

overlain by the Watt Mountain Formation) in northern Alberta, and it is conformably overlain by the Sulphur Point Formation or Presqu'ile Formation in north-eastern British Columbia. It is equivalent to the lower Swan Hills Formation and partly to the Livock River Formation.

References

{{Western Canadian Sedimentary Basin, Fort_Nelson=yes, Northwest_Plains=yes Geologic formations of Alberta Geologic formations of British Columbia Geologic formations of the Northwest Territories Devonian southern paleotropical deposits Middle Devonian Series Devonian Alberta Devonian British Columbia Devonian Northwest Territories Limestone formations of Canada Dolomite formations of Canada Shale formations of Canada