The Coalspur Formation is an
Upper 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 ...
to lower
Palaeocene
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''palaiĂ ...
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 characterize it ...
of 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 ...
in the foothills 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 ...
.
Its deposition spanned the time interval from
latest Cretaceous (
Maastrichtian
The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...
) to early
Palaeocene
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''palaiĂ ...
, and it includes sediments that were deposited before, during, and after the
Cretaceous-Paleogene (K-Pg) extinction event. It includes the economically important
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 ...
deposits of the Coalspur Coal Zone, as well as nonmarine plant and animal
fossil
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 ...
s.
Lithology
The sediments of the Coalspur Formation were eroded 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 northe ...
, and were transported eastward by river systems and deposited in fluvial channel 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 formation consists primarily of sandstones and siltstones, interbedded with mudstones and minor amounts of
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 ...
. Thick coal seams are present locally in the upper portion of the formation, especially in the
Alberta Coal Branch
The Alberta Coal Branch is the name given to a segment of the Canadian National Railway (originally the Grand Trunk Pacific Railway) and the region through which it passes. It is located within Yellowhead County in west-central Alberta, Canada. ...
area southeast of
Hinton, Alberta
Hinton is a town in west-central Alberta, Canada.
It is located in Yellowhead County, northeast of Jasper and about west of Alberta's capital city, Edmonton, at the intersection of Yellowhead and Bighorn Highway
The bighorn sheep (''Ovis ...
. Near the Athabasca River the base consists primarily of
conglomerate and is known as the Entrance Conglomerate.
Stratigraphy and age
The Coalspur Formation is part of the Saunders group. The
K-Pg boundary has been identified within the formation at the base of the lowermost coal seam (the Mynheer seam), based on changes in the fossil
pollen
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...
assemblage and the presence of an
iridium anomaly
The term iridium anomaly commonly refers to an unusual abundance of the chemical element iridium in a layer of rock strata at the Cretaceous–Paleogene (K–Pg) boundary. The unusually high concentration of a rare metal like iridium is often take ...
.
[Jerzykiewicz, T. and Sweet, A.R. 1986. The Cretaceous-Tertiary boundary, central Alberta foothills. In: Stratigraphy. Canadian Journal of Earth Sciences, vol. 23, p. 1356-1374.] The boundary subdivides the Coalspur Formation into an upper member called the Coalspur coal zone which is of early Paleocene age, and an unnamed lower member of latest Cretaceous age.
[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. .]
Thickness and distribution
The Coalspur Formation is present in the Alberta foothills from south of the
Wapiti River
The Wapiti River is a river in eastern British Columbia and western Alberta, Canada. It is a major tributary of the Smoky River, located in the southern area of the Peace River Basin.
Wapiti is named after the Cree word for elk (''waapiti'').
...
to 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 ...
.
The formation is estimated to reach thicknesses of up to about , and the Coalspur coal zone is about to thick.
Relationship to other units
The Coalspur Formation rests abruptly on the
Brazeau Formation and is overlain abruptly by the
Paskapoo Formation
The Paskapoo Formation is a stratigraphic unit of Middle to Late Paleocene age in the Western Canada Sedimentary Basin. The Paskapoo underlies much of southwestern Alberta, and takes the name from the Blindman River (''paskapoo'' means "blind man ...
. It is equivalent to the
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 ...
of the west-central Alberta plains, the
Willow Creek Formation in the southwestern plains, and part or all 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 Frenc ...
in
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 ...
.
The base of the Coalspur coal zone is equivalent to the base of the Ardley coal zone, which is also floored on the K-Pg boundary bed.
Paleontology
Plant fossils
[Bell, W.A. 1949. Uppermost Cretaceous and Paleocene floras of western Canada. Geological Survey of Canada, Bulletin 13, 231 p.] and mammal remains
[Fox, R.C., 1990. The succession of Paleocene mammals in western Canada. Geological Society of America, Special Paper 243, pp. 51-70.] have been described from the Coalspur Formation, but although the lower part of the formation is of Late Cretaceous age, no dinosaur remains have yet been reported.
Fossils reported from the Coalspur Formation:
[Diss Locality]
at Fossilworks
Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database
The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...
.org
*
Batrachosauroididae
** ''
Opisthotriton kayi''
*
Mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s
** ''
Neoplagiaulax cf. nanophus''
** ''
N. cf. nelsoni''
** ''
Simpsonictis cf. jaynanneae''
** ''
Aphronorus sp.''
** ''
Baiotomeus sp.''
** ''
Colpoclaenus sp.''
** ''
Mimetodon sp.''
** ''
Pararyctes sp.''
** ''
Parectypodus sp.''
** ''
Promioclaenus sp.''
** ''
Propalaeosinopa sp.''
** ''
Ptilodus sp.''
**
Condylarthra indet.
**
Lipotyphla indet.
**
Neoplagiaulacidae indet.
**
Paromomyidae indet.
**
Creodonta indet.
Resources
The Coalspur Formation includes seven major seams that range up to in thickness. The coal is of sub-bituminous B to C rank, with a low sulphur content. It is mined in the
Alberta Coal Branch
The Alberta Coal Branch is the name given to a segment of the Canadian National Railway (originally the Grand Trunk Pacific Railway) and the region through which it passes. It is located within Yellowhead County in west-central Alberta, Canada. ...
area and shipped to electric power generating stations in Canada and abroad.
See also
*
List of fossiliferous stratigraphic units in Alberta
*
Edmonton Group
*
Hell Creek Formation
The Hell Creek Formation is an intensively studied division of mostly Upper Cretaceous and some lower Paleocene rocks in North America, named for exposures studied along Hell Creek, near Jordan, Montana. The formation stretches over portions of ...
*
Coal in Alberta
Coal in Alberta is found in the Coalspur Formation in the Western Canada Sedimentary Basin in the foothills of southwestern Alberta. The Coalspur Formation, which has large quantities of high-quality coal, runs from south of the Wapiti River to ...
References
External links
* {{cite web, title= Fossilworks: Gateway to the Paleobiology Database, author= ((Various Contributors to the Paleobiology Database)), url= http://www.fossilworks.org/cgi-bin/bridge.pl?action=home, access-date= 17 December 2021
Geologic formations of Canada
Western Canadian Sedimentary Basin
Paleogene Alberta
Cretaceous Alberta
Paleocene North America
Cretaceous–Paleogene boundary
Maastrichtian Stage of North America
Danian Stage
Sandstone formations
Siltstone formations
Shale formations
Coal formations
Coal in Canada
Paleontology in Alberta