The Kaskapau Formation is a geological

formation Formation may refer to: Linguistics * Back-formation, the process of creating a new lexeme by removing or affixes * Word formation, the creation of a new word by adding affixes Mathematics and science * Cave formation or speleothem, a secondar ...

in North America whose strata date back to the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

. The name derives from ''kaskapahtew'' (ᑲᐢᑲᐸᐦᑌᐤ), the

Cree The Cree ( cr, néhinaw, script=Latn, , etc.; french: link=no, Cri) are a Indigenous peoples of the Americas, North American Indigenous people. They live primarily in Canada, where they form one of the country's largest First Nations in Canada ...

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

Smoky River The 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. It drains an area of . Fro ...

, close to the confluence with the

Puskwaskau River The 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 (Canada), Peace River, Slave River, Great Sla ...

by F.H. McLearn in 1926.

Geographical distribution

The formation is thick in the

Peace River The Peace River (french: links=no, rivière de la Paix) 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 joins the Athabasca River in th ...

and

area, and thickens up to in the foothills of the

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. While their northward limit is easily defined as the ...

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, ...

. It is exposed along the Peace River near

Dunvegan Dunvegan ( gd, Dùn Bheagain) is a village on the Isle of Skye in Scotland. It is famous for Dunvegan Castle, seat of the chief of Clan MacLeod. Dunvegan is within the parish of Duirinish, and Duirinish Parish Church is at Dunvegan. In 2011 it ...

, 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 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 ...

by the

Cardium Formation The Cardium Formation is a stratigraphic unit of Late Cretaceous age in the Western Canada Sedimentary Basin. It takes the name from the fossilized heart-shaped cockle shells in the family Cardiidae (from Greek ''kardiā'', "heart") present. It ...

in the

Pouce Coupe River The Pouce Coupe River is a major tributary of the Peace River (Canada), Peace River in Alberta and British Columbia, Canada. Its name is officially spelled ''Pouce Coupé River'', but it is commonly written without the acute accent. Originating i ...

area. It is conformable underlain by the Dunvegan Formation. The Kaskapau Formation is equivalent to the

Colorado Group Colorado is a geologic name applied to certain rocks of Cretaceous age in the North America, particularly in the western Great Plains. This name was originally applied to classify a group of specific marine formations of shale and chalk kn ...

shale 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 bordere ...

. It is equivalent to the upper Blackstone Formation, the

, and the

Muskiki Formation The Muskiki Formation is a stratigraphical unit of Late Cretaceous age in the Western Canadian Sedimentary Basin. The formation is named after Muskiki Lake and Muskiki Creek, a tributary of the Cardinal River, and was first described in an outcrop ...

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 ...

foothills in western

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 ...

Lithology

The Kaskapau Formation is represented mostly by dark grey

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 ...

, with

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) ...

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

volcanic ash Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcano, volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used t ...

layers may occur in the British Columbia foothills.

Paleontology

Oyster Oyster is the common name for a number of different families of salt-water bivalve molluscs that live in marine or brackish habitats. In some species, the valves are highly calcified, and many are somewhat irregular in shape. Many, but not al ...

fossils are encountered at the base of the formation, and

Inoceramus ''Inoceramus'' (Greek: translation "strong pot") is an extinct genus of fossil marine pteriomorphian bivalves that superficially resembled the related winged pearly oysters of the extant genus '' Pteria''. They lived from the Early Jurassic ...

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

Ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

s are also present in the sand beds, genus encountered include Dunveganoceras and

Watinoceras ''Watinoceras'' is a genus of acanthoceratid ammonite that lived during the early Turonian stage of the Late Cretaceous. Description Early whorls are compressed, finely ribbed with inner and outer ventrolateral and siphonal tubercles as in ...

in the lower part and

Scaphites ''Scaphites'' is a genus of heteromorph ammonites belonging to the Scaphitidae family. They were a widespread genus that thrived during the Late Cretaceous period. Morphology ''Scaphites'' generally have a chambered, boat-shaped shell. The init ...

in the upper part. Microfauna include benthonic (and fewer

planktonic Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...

)

foraminifera Foraminifera (; Latin for "hole bearers"; informally called "forams") are single-celled organisms, members of a phylum or class of amoeboid protists characterized by streaming granular Ectoplasm (cell biology), ectoplasm for catching food and ot ...

. An indeterminate hadrosaurid and a possible nodosaurid are known from Quality Creek.

References

{{WCSB, Northwest_Plains=yes Stratigraphy of Alberta Stratigraphy of British Columbia Upper Cretaceous Series of North America Cretaceous Alberta Cretaceous British Columbia Coniacian Stage Turonian Stage