The Kaskapau Formation is a geological formation in North America whose strata date back to the Late Cretaceous

Late Cretaceous

The Late Cretaceous is the younger of two epochs into which the Cretaceous period is divided in the geologic timescale. Rock strata from this epoch form the Upper Cretaceous series...

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The name derives from kaskapahtew (ᑲᐢᑲᐸᐦᑌᐤ), the Cree

Cree language

Cree is an Algonquian language spoken by approximately 117,000 people across Canada, from the Northwest Territories and Alberta to Labrador, making it the aboriginal language with the highest number of speakers in Canada. It is also spoken in the U.S. state of Montana...

 word for "smoky".. It was first described on the banks of the Smoky River

Smoky River

Smoky River is a river in western Alberta, Canada. It is a major tributary of the Peace River. The descriptive name refers to the presence of "smouldering beds of coal in the riverbank" noted by the Cree Indians....

, close to the confluence with the Puskwaskau River

Puskwaskau River

Puskwaskau River is a short river in Northern Alberta, Canada. It is a tributary of the Smoky River flowing westwards in the Peace River Country. Its waters flow through the Smoky River, Peace River, Slave River, Great Slave Lake and Mackenzie River into the Arctic Ocean.The name of the river...

 by F.H. McLearn in 1926.

Geographical distribution

The formation is 170 metres (557.7 ft) thick in the Peace River

Peace River (Canada)

The Peace River is a river in Canada that originates in the Rocky Mountains of northern British Columbia and flows to the northeast through northern Alberta. The Peace River flows into the Slave River, a tributary of the Mackenzie River. The Mackenzie is the 12th longest river in the world,...

 and Smoky River

Smoky River

Smoky River is a river in western Alberta, Canada. It is a major tributary of the Peace River. The descriptive name refers to the presence of "smouldering beds of coal in the riverbank" noted by the Cree Indians....

 area, and thickens up to 900 metres (2,952.8 ft) in the foothills of the Northern Rocky Mountains

Northern Rocky Mountains

The Northern Rocky Mountains, usually referred to as the Northern Rockies, are a subdivision of the Canadian Rockies comprising the northern half of the Canadian segment of the Rocky Mountains...

 in British Columbia

British Columbia

British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

. It is exposed along the Peace River near Dunvegan

Dunvegan, Alberta

Dunvegan is an unincorporated community within the Municipal District of Fairview No. 136 in northern Alberta, Canada. It is located south of the town of Fairview on the northern bank of the Peace River at the mouth of the Dunvegan Creek....

, as well as in the Smoky River area.

The formation is part of the Smoky River Group, and is conformably overlain by the Bad Heart Formation in the western area, and unconformably

Unconformity

An unconformity is a buried erosion 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 of time before deposition of the younger, but the term is used to describe...

 by the Cardium Formation

Cardium Formation

The Cardium Formation is a stratigraphical unit of Upper Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Cockle shells, and was first described along the Bow River banks by James Hector in 1895.-Lithology:...

 in the Pouce Coupe River

Pouce Coupe River

Pouce Coupe is a river in Alberta and British Columbia, Canada. It is a major tributary of the Peace River.Originating in Alberta's Saddle Hills County, it flows into British Columbia's Peace River Regional District, then returns in Alberta in Clear Hills County, where it empties into the Peace...

 area. It is conformable underlain by the Dunvegan Formation

Dunvegan Formation

The Dunvegan Formation is a stratigraphical unit of Cenomanian age in the Western Canadian Sedimentary Basin.It takes the name from the settlement of Dunvegan, Alberta, and was first described in an outcrop on Peace River near Dunvegan by George Mercer Dawson in 1881.-Lithology:The Dunvegan...

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The Kaskapau Formation is equivalent to the Colorado Group

Colorado Group

The Colorado Group, also called the Colorado shale, is a stratigraphical unit of Cretaceous age in the Western Canadian Sedimentary Basin.It was first described in the Rocky Mountains front ranges of Colorado by A. Hague and S.E...

 shale in central Alberta

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...

. It is equivalent to the upper Blackstone Formation, the Cardium Formation

Cardium Formation

The Cardium Formation is a stratigraphical unit of Upper Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from the Cockle shells, and was first described along the Bow River banks by James Hector in 1895.-Lithology:...

, and the Muskiki Formation

Muskiki Formation

The Muskiki Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin.It takes the name from Muskiki Lake and Muskiki Creek, a tributary of the Cardinal River, and was first described in an outcrop along the Thistle Creek, north of Muskiki Lake, in the...

 in the Canadian Rockies

Canadian Rockies

The Canadian Rockies comprise the Canadian segment of the North American Rocky Mountains range. They are the eastern part of the Canadian Cordillera, extending from the Interior Plains of Alberta to the Rocky Mountain Trench of British Columbia. The southern end borders Idaho and Montana of the USA...

 foothills in western Alberta

Alberta

Alberta is a province of Canada. It had an estimated population of 3.7 million in 2010 making it the most populous of Canada's three prairie provinces...

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Lithology

The Kaskapau Formation is represented mostly by dark grey shale

Shale

Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...

, with sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 tongues and lentils at the base (Doe Creek Member, Pouce Coupe Member). Thin volcanic ash

Volcanic ash

Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...

 layers may occur in the British Columbia foothills.

Paleontology

Oyster

Oyster

The word oyster is used as a common name for a number of distinct groups of bivalve molluscs which live in marine or brackish habitats. The valves are highly calcified....

 fossils are encountered at the base of the formation, and Inoceramus

Inoceramus

Inoceramus is an extinct genus of fossil marine pteriomorphian bivalves that superficially resembled the related winged pearly oysters of the extant genus Pteria....

 fragments (such as I. labiatus) are found throughout the entire stack. Ammonite

Ammonite

Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct subclass within the Molluscan class Cephalopoda which are more closely related to living coleoids Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct...

s are also present in the sand beds, genus encountered include Dunveganoceras and Watinoceras in the lower part and Scaphites

Scaphites

Scaphites is a genus of extinct cephalopod belonging to the family of heteromorph ammonites . They were a widespread genus that thrived during the Cretaceous period....

 in the upper part. Microfauna include benthonic

Benthic zone

The benthic zone is the ecological region at the lowest level of a body of water such as an ocean or a lake, including the sediment surface and some sub-surface layers. Organisms living in this zone are called benthos. They generally live in close relationship with the substrate bottom; many such...

 (and fewer planktonic) foraminifera

Foraminifera

The Foraminifera , or forams for short, are a large group of amoeboid protists which are among the commonest plankton species. They have reticulating pseudopods, fine strands of cytoplasm that branch and merge to form a dynamic net...

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