The Paskapoo Formation is a

stratigraphic Stratigraphy is a branch of geology concerned with the study of rock layers (strata) and layering (stratification). It is primarily used in the study of sedimentary and layered volcanic rocks. Stratigraphy has three related subfields: lithostra ...

unit of Middle to Late Paleocene

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 Canada 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 ...

. The Paskapoo underlies much of southwestern

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 takes the name from the

Blindman River The Blindman River is in south-central Alberta. It forms south of Winfield and flows southeastward before joining the Red Deer River near Red Deer. The Blindman is bridged by Alberta Highway 20 a number of times in its upper reaches, before passi ...

(''paskapoo'' means "blind man" in

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 ...

). It was first described from

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 ...

s along that river, near its confluence with the

Red Deer River The Red Deer River is a river in Alberta and a small portion of Saskatchewan, Canada. It is a major tributary of the South Saskatchewan River and is part of the larger Saskatchewan-Nelson system that empties into Hudson Bay. Red Deer River ...

north of the city of

Red Deer The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Iran, and parts of wes ...

, by J.B. Tyrrell in 1887.Tyrrell, J.B., 1887. ''Report on a part of northern Alberta and portions of adjacent Districts of Assiniboia and Saskatchewan;''

Geological Survey of Canada The Geological Survey of Canada (GSC; french: Commission géologique du Canada (CGC)) is a Canadian federal government agency responsible for performing geological surveys of the country, developing Canada's natural resources and protecting the en ...

, Annual Report 1886, v.11, Part E, p.1-176 It is important for its freshwater

aquifers An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials (gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characterist ...

, its

coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal is formed when dea ...

resources, and its

fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

, as well as having been the source of sandstone for the construction of fire-resistant buildings in

Calgary Calgary ( ) is the largest city in the western Canadian province of Alberta and the largest metro area of the three Prairie Provinces. As of 2021, the city proper had a population of 1,306,784 and a metropolitan population of 1,481,806, makin ...

during the early 1900s.

Lithology and environment of deposition

The Paskapoo Formation is of fluvial origin and consists primarily of

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 ...

s and

mudstone Mudstone, a type of mudrock, is a fine-grained sedimentary rock whose original constituents were clays or muds. Mudstone is distinguished from '' shale'' by its lack of fissility (parallel layering).Blatt, H., and R.J. Tracy, 1996, ''Petrology. ...

s, with lesser amounts of pebble-conglomerate and

, and minor

bentonite Bentonite () is an absorbent swelling clay consisting mostly of montmorillonite (a type of smectite) which can either be Na-montmorillonite or Ca-montmorillonite. Na-montmorillonite has a considerably greater swelling capacity than Ca-mon ...

. The sediments were derived from the

Canadian Cordillera The Pacific Cordillera, also known as the Western Cordillera or simply The Cordillera, is a top-level physiographic region of Canada, referring mainly to the extensive cordillera system in Western and Northwestern Canada that constitutes the north ...

during tectonic uplift and erosion in the late stages of the

Laramide Orogeny The Laramide orogeny was a time period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the o ...

. They were transported eastward by river systems and deposited in fluvial and

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...

environments. The sandstones were deposited in river channels. They are cross-bedded, medium- to coarse-grained, and locally conglomeratic. The siltstones and mudstones represent

crevasse splay A crevasse splay is a sedimentary fluvial deposit which forms when a stream breaks its natural or artificial levees and deposits sediment on a floodplain. A breach that forms a crevasse splay deposits sediments in similar pattern to an alluvial f ...

overbank An overbank is an alluvial geological deposit consisting of sediment that has been deposited on the floodplain of a river or stream by flood waters that have broken through or overtopped the banks. The sediment is carried in suspension, and be ...

and shallow

pond A pond is an area filled with water, either natural or artificial, that is smaller than a lake. Defining them to be less than in area, less than deep, and with less than 30% emergent vegetation helps in distinguishing their ecology from th ...

environments. They include plant fossils, rooted horizons and

paleosols In the geosciences, paleosol (''palaeosol'' in Great Britain and Australia) is an ancient soil that formed in the past. The precise definition of the term in geology and paleontology is slightly different from its use in soil science. In geol ...

.Hoffman, G.L. and Stockey, R.A., 1999. Geological setting and paleobotany of the Joffre Bridge Roadcut fossil locality (Late Paleocene), Red Deer Valley, Alberta. Canadian Journal of Earth Science, 36: 2073-2084. Carbonaceous mudstones and coaly beds that represent oxygen-poor, swampy settings are thin and discontinuous, but common. Thick coal seams that formed in well-developed

swamps A swamp is a forested wetland.Keddy, P.A. 2010. Wetland Ecology: Principles and Conservation (2nd edition). Cambridge University Press, Cambridge, UK. 497 p. Swamps are considered to be transition zones because both land and water play a role in ...

are present only in the youngest portion of the formation, which is preserved near Hinton.

Stratigraphy

Although some early workers included the underlying

Scollard Formation The Scollard Formation is an Upper Cretaceous to lower Palaeocene stratigraphic unit of the Western Canada Sedimentary Basin in southwestern Alberta. Its deposition spanned the time interval from latest Cretaceous to early Paleocene, and it inclu ...

as the lower part of the Paskapoo, the two are now treated separately. The base of the Paskapoo Formation, designated the Haynes Member, consists primarily of cliff-forming sandstones and pebble-conglomerates, interbedded with lesser amounts of siltstone and mudstone. In the overlying Lacombe Member, siltstones and mudstones are dominant, with interbeds of fine-grained sandstone, carbonaceous mudstones, paleosols, and thin coals. The Dalehurst Member at the top of the formation consists of the Obed coal zone.Demchuk, T.D. and Hills, L.V., 1991. A re-examination of the Paskapoo Formation in the central Alberta Plains: the designation of three new members. Canadian Journal of Earth Science 27: 1263-1269. The Dalehurst strata are similar to those of the Lacombe Member, but the Dalehurst sequence includes up to six coal seams, with individual seams up to thick. Blindman River Mouth

Distribution

The Paskapoo Formation underlies much of southwestern Alberta. It is thickest in the foothills of 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 ...

, and thins eastward to the

112th meridian west The meridian 112° west of Prime Meridian, Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole. The 112th meridian wes ...

in the plains. The formation is more than thick in the foothills, and about near Calgary.Glass, D.J. (editor) 1997. Lexicon of Canadian Stratigraphy, vol. 4, Western Canada including eastern British Columbia, Alberta, Saskatchewan and southern Manitoba. Canadian Society of Petroleum Geologists, Calgary, 1423 p. on CD-ROM. . It is assumed that it originally reached thicknesses as great as in some areas prior to erosion. The formation is exposed at the surface along a trend that extends from Calgary to west of

Edmonton Edmonton ( ) is the capital city of the Canadian province of Alberta. Edmonton is situated on the North Saskatchewan River and is the centre of the Edmonton Metropolitan Region, which is surrounded by Alberta's central region. The city ancho ...

. Good outcrops can be seen in the eastern reaches of the foothills, and along the

Bow River The Bow River is a river in Alberta, Canada. It begins within the Canadian Rocky Mountains and winds through the Alberta foothills onto the prairies, where it meets the Oldman River, the two then forming the South Saskatchewan River. These w ...

in and around Calgary (for example at

Paskapoo Slopes The Paskapoo Slopes are a significant natural, environmental and cultural feature on the western side of Calgary, Alberta. They have a high visual impact and are a prominent landmark along the Trans Canada Highway, Calgary's western gateway from ...

), the

near Red Deer, the

North Saskatchewan River The North Saskatchewan River is a glacier-fed river that flows from the Canadian Rockies continental divide east to central Saskatchewan, where it joins with the South Saskatchewan River to make up the Saskatchewan River. Its water flows eventual ...

west of Edmonton, and the

Athabasca River The Athabasca River (French: ''Rivière Athabasca'') is a river in Alberta, Canada, which originates at the Columbia Icefield in Jasper National Park and flows more than before emptying into Lake Athabasca. Much of the land along its banks is pro ...

. The Dalehurst Member is an erosional remnant and is confined to an area adjacent to the foothills near Hinton and Obed.

Relationship to other units

The Paskapoo Formation underlies the present day erosional surface and it is exposed in outcrop in many areas. Cover, where present, consists of

Quaternary The Quaternary ( ) is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ...

sediments or, on a few localized plateaus, of younger

Tertiary Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...

gravels. The Paskapoo rests on the

in the Alberta plains, and on the equivalent Coalspur Formation in the Alberta foothills. The lower boundary has been defined as the erosional base of the first prominent sandstone above the Ardley coal zone of the Scollard Formation. It has been established that, in the type area near Red Deer, this erosional surface represents a hiatus of about 1-2 million years. In the foothills, the contact with the underlying Coalspur Formation is less distinctive but is again placed at the base of the first dominantly sandstone unit overlying a dominantly coal and mudstone unit.Lerbekmo, J.F. and Sweet, A.R., 2008. Magnetobiostratigraphy of the continental Paleocene upper Coalspur and Paskapoo formations near Hinton, Alberta. Bulletin of Canadian Petroleum Geology 56: 118-146. The Paskapoo grades into the equivalent

Porcupine Hills Formation The Porcupine Hills Formation is a stratigraphic unit of middle to late Paleocene age in the Western Canada Sedimentary Basin. It takes its name from the Porcupine Hills of southwestern Alberta, and was first described in outcrop by George M ...

south of Calgary. It is correlated with upper part of the

Ravenscrag Formation The Ravenscrag Formation is a stratigraphic unit of early Paleocene age in the Western Canada Sedimentary Basin. It was named for the settlement of Ravenscrag, Saskatchewan, and was first described from outcrops at Ravenscrag Butte near the Fr ...

of southern

Saskatchewan Saskatchewan ( ; ) is a Provinces and territories of Canada, province in Western Canada, western Canada, bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and on t ...

and the

Fort Union Formation The Fort Union Formation is a geologic unit containing sandstones, shales, and coal beds in Wyoming, Montana, and parts of adjacent states. In the Powder River Basin, it contains important economic deposits of coal, uranium, and coalbed methane. ...

of Montana and North Dakota, which are not contiguous with it but are of similar age.

Age

The middle to late Paleocene age of the Paskapoo Formation is based primarily on Paskapoo mammal fossils, which indicate

North American land mammal age The North American land mammal ages (NALMA) establishes a geologic timescale for North American fauna beginning during the Late Cretaceous and continuing through to the present. These periods are referred to as ages or intervals (or stages when ref ...

s of middle to late

Tiffanian The Tiffanian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 60,200,000 to 56,800,000 years BP lasting . It is usually c ...

. It is supported by detailed palynostratigraphic and magnetostratigraphic studies. It is equivalent to a radiometric age of approximately 62.5 to 58.5 million years.

Paleontology

The Paskapoo Formation contains remains of vertebrates, especially mammals, and plants. Material from the following groups of mammals has been reported from the Paskapoo Formation:

Multituberculata Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, a ...

, Marsupicarnivora, Lyptophyla, Dermoptera,

Primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers and the simians (monkeys and apes, the latter including huma ...

Carnivora Carnivora is a Clade, monophyletic order of Placentalia, placental mammals consisting of the most recent common ancestor of all felidae, cat-like and canidae, dog-like animals, and all descendants of that ancestor. Members of this group are f ...

Condylarth Condylarthra is an informal group – previously considered an order – of extinct placental mammals, known primarily from the Paleocene and Eocene epochs. They are considered early, primitive ungulates. It is now largely considered to be a waste ...

a, and

Pantodonta Pantodonta is an extinct suborder (or, according to some, an order) of eutherian mammals. These herbivorous mammals were one of the first groups of large mammals to evolve (around 66 million years ago) after the end of the Cretaceous. The last ...

, as well as the small, possibly venomous mammal ''

Bisonalveus ''Bisonalveus'' is an extinct genus of shrew-like mammals that were presumably ground-dwelling and fed on plants and insects. ''Bisonalveus'' fossils have been discovered in the upper Great Plains region of North America, including sites in mode ...

''.Fox, R.C., 1990. The succession of Paleocene mammals in western Canada. Geological Society of America, Special Paper 243, pp. 51-70. The Paskapoo has also yielded articulated and fragmentary skeletons of freshwater fish, impressions of insect wings and larvae, and shells of freshwater molluscs. An unnamed species of the amphibian '' Albanerpeton'' is known from the formation, which is the final record of albanerpetontids from North America. Plant fossils were first collected from the Paskapoo Formation by Tyrrell in 1886, and since that time a wide variety have been described. These include specimens of the

fern A fern (Polypodiopsida or Polypodiophyta ) is a member of a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. The polypodiophytes include all living pteridophytes except t ...

s ''

Azolla ''Azolla'' (mosquito fern, duckweed fern, fairy moss, water fern) is a genus of seven species of aquatic ferns in the family Salviniaceae. They are extremely reduced in form and specialized, looking nothing like other typical ferns but more rese ...

'',Hoffman, G.L. and Stockey, R.A., 1994. Sporophytes, megaspores and massulae of ''Azolla stanleyi'' from the Paleocene Joffre Bridge locality, Canada. Canadian Journal of Botany, 72: 301-308. ''

Onoclea ''Onoclea'' is a genus of plants in the family Onocleaceae, native to moist habitats in eastern Asia and eastern North America. They are deciduous ferns with sterile fronds arising from creeping rhizomes In botany and dendrology, a rhizome ...

'',Rothwell, G.W. and Stockey, R.A., 1991. ''Onoclea sensibilis'' in the Paleocene of North America, a dramatic example of structural and ecological stasis. Review of Palaeobotany and Palynology, 70: 113–124. and ''Speirseopteris'';Stockey R.A., Lantz, T.C. and Rothwell, G.W. 2006. ''Speirseopteris orbiculata'' (Thelypteridaceae), a derived fossil filicalean from the Paleocene of western North America. International Journal of Plant Sciences, 167: 729–736. the

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

s ''

Metasequoia ''Metasequoia'', or dawn redwoods, is a genus of fast-growing deciduous trees, one of three species of pinophyta, conifers known as redwoods. The living species ''Metasequoia glyptostroboides'' is native to Lichuan, Hubei, Lichuan county in Hube ...

'' (including ''

Metasequoia foxii ''Metasequoia foxii'' is an extinct redwood species in the family Cupressaceae described from numerous fossils of varying growth stage. The species is solely known from the Paleocene sediments exposed in central Alberta, Canada. It is one of th ...

'') and ''

Glyptostrobus ''Glyptostrobus'' is a small genus of conifers in the family Cupressaceae (formerly in the family Taxodiaceae). The sole living species, '' Glyptostrobus pensilis'', is native to subtropical southeastern China, from Fujian west to southeast Yu ...

''; and the dicots ''Palaeocarpinus''Sun, F. and Stockey, R.A., 1992. A new species of ''Palaeocarpinus'' (Betulaceae) from the Paleocene of Alberta, Canada. International Journal of Plant Sciences, 153: 136–146. (a member of the birch family), ''

Cercidiphyllum ''Cercidiphyllum'' is a genus containing two species of plants, both commonly called katsura. They are the sole members of the monotypic family Cercidiphyllaceae. The genus is native to Japan and China and unrelated to ''Cercis'' (redbuds). Desc ...

'' (including ''Joffrea''Crane, P.R., and Stockey, R.A. 1985. Growth and reproductive biology of ''Joffrea speirsii'', a ''Cercidiphyllum''-like plant from the Late Paleocene of Alberta, Canada. Canadian Journal of Botany, 63: 340–364.), ''

Platanus ''Platanus'' is a genus consisting of a small number of tree species native to the Northern Hemisphere. They are the sole living members of the family Platanaceae. All mature members of ''Platanus'' are tall, reaching in height. All except f ...

'',Pigg, K.B. and Stockey, R.A., 1991. Platanaceous plants from the Paleocene of Alberta. Rev. Palaeobot. Palynol. 70:125-146. and ''Beringiaphyllum''Manchester, S.R., Crane, P.R. and Golovneva, L.B., 1999. An extinct genus with affinities to extant ''Davidia'' and ''Camptotheca'' (Cornales) from the Paleocene of North America and eastern Asia. International Journal of Plant Sciences, 160: 188–207. (a relative of dogwoods).

Resources

Building stone

Sandstone Building Lougheed House Calgary

During the early 1900s, outcrops of Paskapoo sandstone in the Calgary area were quarried for building stone due to the requirement for fire-resistant buildings following the

Calgary Fire of 1886 The Calgary Fire of 1886, also known as the Great Calgary Fire of 1886, was a conflagration that burned in the Canadian city of Calgary on Sunday November 7, 1886. The fire began at the rear wall of the local flour and feed store, and spread thro ...

. Many of Calgary's early landmark buildings, such as

Lougheed House Lougheed House, or as it was originally known Beaulieu, (French meaning "beautiful place") is a National Historic Site located in the Beltline district of Calgary, Alberta. Originally constructed in 1891 as a home for Senator James Alexander Lou ...

Burns Manor Burns Manor was the Calgary residence of Senator Patrick Burns (businessman), Pat Burns, a successful businessman who founded Burns Meat. It was located at 510 13th Avenue S.W. in the Beltline, Calgary, Beltline District of Calgary, Alberta. Cons ...

, and some of the buildings along

Stephen Avenue Stephen Avenue is a major pedestrian mall in downtown Calgary, Alberta, Canada. The mall is the portion of 8 Avenue SW between 4 Street SW and 1 Street SE. It is open to vehicles only from 6:00 p.m. to 6:00 a.m. The street is known for some of C ...

, were built using Paskapoo sandstone, and Calgary became known as the Sandstone City. Paskapoo sandstone is still used in

landscaping Landscaping refers to any activity that modifies the visible features of an area of land, including the following: # Living elements, such as flora or fauna; or what is commonly called gardening, the art and craft of growing plants with a goal o ...

in the Calgary area today.

Coal

Coal has been mined from the Obed coal zone in the Paskapoo Formation near Hinton. It is of high-volatile

bituminous Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term a ...

rank with a low sulphur content, and it was shipped to markets in eastern Canada and the Pacific Rim.

Groundwater

Paskapoo Formation

aquifer An aquifer is an underground layer of water-bearing, permeable rock, rock fractures, or unconsolidated materials (gravel, sand, or silt). Groundwater from aquifers can be extracted using a water well. Aquifers vary greatly in their characterist ...

s are a very important source of water for

irrigation Irrigation (also referred to as watering) is the practice of applying controlled amounts of water to land to help grow Crop, crops, Landscape plant, landscape plants, and Lawn, lawns. Irrigation has been a key aspect of agriculture for over 5,00 ...

and

drinking Drinking is the act of ingesting water or other liquids into the body through the mouth, proboscis, or elsewhere. Humans drink by swallowing, completed by peristalsis in the esophagus. The physiological processes of drinking vary widely among o ...

in southwestern Alberta.

References

{{Western Canadian Sedimentary Basin, Central_Plains=yes Paleogene Alberta Paleocene North America Western Canadian Sedimentary Basin Building stone Thanetian Stage