Paskapoo Formation

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Paskapoo Formation
Stratigraphic range: Paleocene
Peskapoo Sandstone.JPG
Outcrop of Paskapoo sandstone in Calgary
Type Geological formation
Underlies Tertiary gravel, Quaternary sediments, present erosional surface
Overlies Scollard Formation, Coalspur Formation
Thicknessup to 600 metres (1,970 ft) [1]
Lithology
Primary mudstone, siltstone, sandstone
Other conglomerate, coal
Location
Coordinates 52°21′18″N113°45′28″W / 52.355031°N 113.757797°W / 52.355031; -113.757797 (Paskapoo)
Region Alberta
CountryCanada
Type section
Named for Cree: paskapiw, lit.  'He is blind', from Blindman River
Named by J.B. Tyrrell, 1887

The Paskapoo Formation is a stratigraphic unit of Middle to Late Paleocene age in the Western Canada Sedimentary Basin. [2] The Paskapoo underlies much of southwestern Alberta, [3] and takes the name from the Blindman River (paskapiw means 'He is blind' in Cree [4] ). It was first described from outcrops along that river, near its confluence with the Red Deer River north of the city of Red Deer, by Joseph Tyrrell in 1887. [5] It is important for its freshwater aquifers, its coal resources, and its fossil record, as well as having been the source of sandstone for the construction of fire-resistant buildings in Calgary during the early 1900s.

Contents

Lithology and environment of deposition

The Paskapoo Formation is of fluvial origin and consists primarily of sandstones, siltstones and mudstones, with lesser amounts of pebble-conglomerate and coal, and minor bentonite. The sediments were derived from the Canadian Cordillera during tectonic uplift and erosion in the late stages of the Laramide Orogeny. They were transported eastward by river systems and deposited in fluvial and floodplain environments. [6]

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, overbank and shallow pond environments. They include plant fossils, rooted horizons and paleosols. [7] 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 are present only in the youngest portion of the formation, which is preserved near Hinton. [6]

Stratigraphy

Mudstones and siltstones of the Paskapoo Formation exposed along the Red Deer River, downstream from its confluence with the Blindman River. Paskapoo Mudstones Red Deer.jpg
Mudstones and siltstones of the Paskapoo Formation exposed along the Red Deer River, downstream from its confluence with the Blindman River.

Although some early workers included the underlying Scollard Formation as the lower part of the Paskapoo, the two are now treated separately. [6] 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. [8] 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 5 metres (20 ft) thick. [9]

The Blindman River is deeply incised into Paskapoo Formation bedrock at its confluence with the Red Deer River. Blindman River Mouth.jpg
The Blindman River is deeply incised into Paskapoo Formation bedrock at its confluence with the Red Deer River.

Distribution

The Paskapoo Formation underlies much of southwestern Alberta. [3] It is thickest in the foothills of the Canadian Rockies, and thins eastward to the 112th meridian west in the plains. The formation is more than 750 metres (2,460 ft) thick in the foothills, [10] and about 600 metres (1,970 ft) near Calgary. [1] It is assumed that it originally reached thicknesses as great as 1,000 metres (3,280 ft) in some areas prior to erosion.

The formation is exposed at the surface along a trend that extends from Calgary to west of Edmonton. Good outcrops can be seen in the eastern reaches of the foothills, and along the Bow River in and around Calgary (for example at Paskapoo Slopes), the Red Deer River near Red Deer, the North Saskatchewan River west of Edmonton, and the Athabasca River. The Dalehurst Member is an erosional remnant and is confined to an area adjacent to the foothills near Hinton and Obed. [8]

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 sediments or, on a few localized plateaus, of younger Tertiary gravels. [6]

The Paskapoo rests on the Scollard Formation in the Alberta plains, and on the equivalent Coalspur Formation in the Alberta foothills. [11] The lower boundary has been defined as the erosional base of the first prominent sandstone above the Ardley coal zone of the Scollard Formation. [12] It has been established that, in the type area near Red Deer, this erosional surface represents a hiatus of about 1-2 million years. [6] 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. [10]

The Paskapoo grades into the equivalent Porcupine Hills Formation south of Calgary. [3] It is correlated with upper part of the Ravenscrag Formation of southern Saskatchewan and the Fort Union Formation of Montana and North Dakota, which are not contiguous with it but are of similar age. [2]

Age

The middle to late Paleocene age of the Paskapoo Formation is based primarily on Paskapoo mammal fossils, which indicate North American land mammal ages of middle to late Tiffanian. [13] It is supported by detailed palynostratigraphic and magnetostratigraphic studies. [6] [14] It is equivalent to a radiometric age of approximately 62.5 to 58.5 million years. [6]

Paleontology

Fossil Platanus leaf from the Paskapoo Formation near Red Deer. Fossil Platanus leaf.jpg
Fossil Platanus leaf from the Paskapoo Formation near Red Deer.

The Paskapoo Formation contains remains of vertebrates, [15] especially mammals, and plants. Material from the following groups of mammals has been reported from the Paskapoo Formation: Multituberculata, Marsupicarnivora, Lyptophyla, Dermoptera, Primates, Carnivora, Condylartha, and Pantodonta, as well as the small, possibly venomous mammal Bisonalveus . [13] The Paskapoo has also yielded articulated and fragmentary skeletons of freshwater fish, impressions of insect wings and larvae, and shells of freshwater molluscs. [7] An unnamed species of the amphibian Albanerpeton is known from the formation, which is the final record of albanerpetontids from North America. [16]

Plant fossils were first collected from the Paskapoo Formation by Tyrrell in 1886, [5] and since that time a wide variety have been described. These include specimens of the ferns Azolla , [17] Onoclea , [18] and Speirseopteris; [19] the conifers Metasequoia (including Metasequoia foxii ) and Glyptostrobus ; and the dicots Palaeocarpinus [20] (a member of the birch family), Cercidiphyllum (including Joffrea [21] ), Platanus , [22] and Beringiaphyllum [23] (a relative of dogwoods).

Resources

Building stone

An example of Paskapoo sandstone used in construction: the east wall of the Lougheed House, Calgary. Sandstone Building Lougheed House Calgary.jpg
An example of Paskapoo sandstone used in construction: the east wall of the 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. Many of Calgary's early landmark buildings, such as Lougheed House, Burns Manor, and some of the buildings along Stephen Avenue, were built using Paskapoo sandstone, and Calgary became known as the Sandstone City. [24] Paskapoo sandstone is still used in landscaping in the Calgary area today.[ when? ]

Coal

Coal has been mined from the Obed coal zone in the Paskapoo Formation near Hinton. It is of high-volatile bituminous rank with a low sulphur content, and it was shipped to markets in eastern Canada and the Pacific Rim. [9]

Groundwater

Paskapoo Formation aquifers are a very important source of water for irrigation and drinking in southwestern Alberta. [6]

Related Research Articles

<span class="mw-page-title-main">Scollard Formation</span> Upper Cretaceous to lower Palaeocene stratigraphic unit of the Western Canada Sedimentary Basin

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 includes sediments that were deposited before, during, and after the Cretaceous-Paleogene (K-Pg) extinction event. It is significant for its fossil record, and it includes the economically important coal deposits of the Ardley coal zone.

The Wapiti Formation is a geological formation of the Western Canada Sedimentary Basin in northwestern Alberta, and northeastern British Columbia, Canada. Its deposition spanned the time interval from the lower Campanian through to the upper Maastrichtian, between approximately 80 and 68 Ma. It was named by G.M. Dawson in 1881, presumably for exposures along the lower part of the Wapiti River and downstream along the Smoky River in Alberta.

<span class="mw-page-title-main">St. Mary River Formation</span> Geologic formation in western Canada

The St. Mary River Formation is a geologic formation of Late Cretaceous age of the Western Canada Sedimentary Basin in southwestern Alberta and northwesternmost Montana. It was first described from outcrops along the St. Mary River by George Mercer Dawson in 1883, and it takes its name from the river.

The Willow Creek Formation is a stratigraphic unit of Late Cretaceous to Early Paleocene age in the Western Canada Sedimentary Basin of southwestern Alberta. It was first described by George Mercer Dawson in 1883 along the Willow Creek, a tributary of the Oldman River. Williams and Dyer defined the type section in 1930 at the mouth of Willow Creek, east of Fort Macleod.

Bullhead Group is a stratigraphic unit of Lower Cretaceous age in the Western Canada Sedimentary Basin of northeastern British Columbia and western Alberta. It was first defined by F.H. McLearn in 1918 as the Bullhead Mountain Formation, but later was upgraded to group status. It consists of the Cadomin and Gething Formations, although some early workers included the Bluesky Formation and others in the group.

The Mist Mountain Formation is a geologic formation of latest Jurassic to earliest Cretaceous age in the Western Canada Sedimentary Basin that is present in the southern and central Canadian Rockies. It was named for outcrops along the western spur of Mist Mountain in Alberta by D.W. Gibson in 1979. The Mist Mountain Formation contains economically important coal seams that have been mined in southeastern British Columbia and southwestern Alberta.

<span class="mw-page-title-main">Edmonton Group</span>

Within the earth science of geology, the Edmonton Group is a Late Cretaceous to early Paleocene stratigraphic unit of the Western Canada Sedimentary Basin in the central Alberta plains. It was first described as the Edmonton Formation by Joseph Burr Tyrrell in 1887 based on outcrops along the North Saskatchewan River in and near the city of Edmonton. E.J.W. Irish later elevated the formation to group status and it was subdivided into four separate formations. In ascending order, they are the Horseshoe Canyon, Whitemud, Battle and Scollard Formations. The Cretaceous-Paleogene boundary occurs within the Scollard Formation, based on dinosaurian and microfloral evidence, as well as the presence of the terminal Cretaceous iridium anomaly.

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 Frenchman River by N.B. Davis in 1918.

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 Mercer Dawson in 1883.

<span class="mw-page-title-main">Morrissey Formation</span>

The Morrissey Formation is a stratigraphic unit of Late Jurassic (Portlandian) age in the Western Canada Sedimentary Basin. It is named for outcrops on Morrissey Ridge, 16 kilometres (10 mi) southeast of Fernie, British Columbia, and is present in southeastern British Columbia and southwestern Alberta.

The Elk Formation is a stratigraphic unit of the Western Canada Sedimentary Basin that is present in southeastern British Columbia and southwestern Alberta. It is probably of Early Cretaceous age, but in some areas its strata could be as old as Late Jurassic. It includes minor thin coal beds and was named for outcrops near the now-abandoned Elk River coal mine east of Fernie, British Columbia.

The Coalspur Formation is an Upper Cretaceous to lower Palaeocene stratigraphic unit of the Western Canada Sedimentary Basin in the foothills of southwestern Alberta. Its deposition spanned the time interval from latest Cretaceous (Maastrichtian) to early Palaeocene, and it includes sediments that were deposited before, during, and after the Cretaceous-Paleogene (K-Pg) extinction event. It includes the economically important coal deposits of the Coalspur Coal Zone, as well as nonmarine plant and animal fossils.

The Blairmore Group, originally named the Blairmore Formation, is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in southwestern Alberta and southeastern British Columbia. It is subdivided into four formations: Cadomin Formation, Gladstone, Beaver Mines and Ma Butte, all of which are defined by type sections, most of which contain plant fossils. In some areas the Blairmore contains significant reservoirs of natural gas.

The Beaver Mines Formation is a stratigraphic unit of Early Cretaceous (Albian) age in the Western Canada Sedimentary Basin that is present in southwestern Alberta and southeastern British Columbia, Canada. It was established by G.B. Mellon in 1967 who named it for the hamlet of Beaver Mines, Alberta. It contains a variety of plant fossils.

The Battle Formation is a geologic formation of Late Cretaceous (Maastrichtian) age in the Western Canada Sedimentary Basin. It is present throughout much of the central Alberta plains, where it is an important stratigraphic marker in the nonmarine Upper Cretaceous sequence. It was formally named by G.M. Furnival in 1942 and given formation status by E.J.W. Irish in 1970.

The Gorman Creek Formation is a geologic formation of Early Cretaceous (Valanginian) age in the Western Canada Sedimentary Basin that consists primarily of nonmarine sediments. It is present in the northern foothills of the Canadian Rockies and the adjacent plains in northeastern British Columbia. Plant fossils and dinosaur tracks have been described from its strata.

The Luscar Group is a geologic unit of Early Cretaceous age in the Western Canada Sedimentary Basin that is present in the foothills of southwestern Alberta. It is subdivided into a series of formations, some of which contain economically significant coal deposits that have been mined near Cadomin and Luscar. Coal mining in those areas began in the early 1900s and continues near Luscar as of 2016.

The Gladstone Formation is a stratigraphic unit of Early Cretaceous (Aptian) age in the Western Canada Sedimentary Basin. It is present in the foothills of southwestern Alberta and is named for outcrops along Gladstone Creek, a tributary of the Castle River south of the Crowsnest Pass.

The Ma Butte Formation is a stratigraphic unit of Early Cretaceous (Albian) age in the Western Canada Sedimentary Basin. It was named for Ma Butte, a mountain north of Coleman, Alberta, by J.R. McLean in 1980. It is present in the foothills of southwestern Alberta and it contains plant fossils.

The geology of Alberta encompasses parts of the Canadian Rockies and thick sedimentary sequences, bearing coal, oil and natural gas, atop complex Precambrian crystalline basement rock.

References

  1. 1 2 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. ISBN   0-920230-23-7.
  2. 1 2 Mossop, G.D. and Shetsen, I. (compilers), Canadian Society of Petroleum Geologists (1994). "The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 24: Upper Cretaceous and Tertiary strata of the Western Canada Sedimentary Basin". Archived from the original on 2016-07-01. Retrieved 2016-06-20.{{cite web}}: CS1 maint: multiple names: authors list (link)
  3. 1 2 3 Prior, G. J., Hathaway, B., Glombick, P.M., Pana, D.I., Banks, C.J., Hay, D.C., Schneider, C.L., Grobe, M., Elgr, R., and Weiss, J.A. (2013). "Bedrock Geology of Alberta. Alberta Geological Survey, Map 600" . Retrieved 2016-06-20.{{cite web}}: CS1 maint: multiple names: authors list (link)
  4. ↑ "Search results". www.creedictionary.com. Retrieved 2023-01-11.
  5. 1 2 Tyrrell, J.B., 1887. Report on a part of northern Alberta and portions of adjacent Districts of Assiniboia and Saskatchewan; Geological Survey of Canada, Annual Report 1886, v.11, Part E, p.1-176
  6. 1 2 3 4 5 6 7 8 Hamblin, A.P. (2004). "Paskapoo-Porcupine Hills Formation in western Alberta: Synthesis of regional geology and resource potential. Geological Survey of Canada, Open File 4679" . Retrieved 2013-08-01.
  7. 1 2 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.
  8. 1 2 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.
  9. 1 2 Mossop, G.D. and Shetsen, I. (compilers), Canadian Society of Petroleum Geologists (1994). "The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 33: Coal Resources of the Western Canada Sedimentary Basin". Archived from the original on 2016-07-01. Retrieved 2016-06-20.{{cite web}}: CS1 maint: multiple names: authors list (link)
  10. 1 2 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.
  11. ↑ Alberta Geological Survey, 2013. "Alberta Table of Formations; Alberta Energy Regulator" . Retrieved 2016-06-20.
  12. ↑ Alberta Geological Survey. "Scollard & Paskapoo Formations" . Retrieved 2009-05-30.
  13. 1 2 Fox, R.C., 1990. The succession of Paleocene mammals in western Canada. Geological Society of America, Special Paper 243, pp. 51-70.
  14. ↑ Lerbekmo, J.F., Demchuk, T.D., Evans, M.E. and Hoye, G.S., 1992. Magnetostratigraphy and biostratigraphy of the continental Paleocene of the Red Deer Valley, Alberta, Canada. Bulletin of Canadian Petroleum Geology, 40: 24-35.
  15. ↑ Vertebrate track sites of Canada. "Paskapoo Formation" . Retrieved 2009-05-30.
  16. ↑ Fox, Richard C.; Naylor, Bruce G. (1982-01-01). "A reconsideration of the relationships of the fossil amphibian Albanerpeton". Canadian Journal of Earth Sciences. 19 (1): 118–128. doi:10.1139/e82-009. ISSN   0008-4077.
  17. ↑ 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.
  18. ↑ 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.
  19. ↑ 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.
  20. ↑ 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.
  21. ↑ 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.
  22. ↑ Pigg, K.B. and Stockey, R.A., 1991. Platanaceous plants from the Paleocene of Alberta. Rev. Palaeobot. Palynol. 70:125-146.
  23. ↑ 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.
  24. ↑ "The Sandstone City". 2002-11-21. Archived from the original on August 13, 2011. Retrieved 2013-08-04.
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