Scollard Formation

The Scollard Formation consists primarily of sandstones and siltstones, interbedded with mudstones and, in the upper portion, coal seams, as well as minor amounts of bentonite.{{Cite web|url=http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch24/ch_24.html|title=The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 24: Upper Cretaceous and Tertiary strata of the Western Canada Sedimentary Basin|author=Mossop, G.D. and Shetsen, I., (compilers), Canadian Society of Petroleum Geologists|year=1994|access-date=2013-08-01|url-status=dead|archive-url=https://web.archive.org/web/20130721174353/http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch24/ch_24.html|archive-date=2013-07-21}} The sediments were eroded from the Canadian Cordillera, and were transported eastward by river systems and deposited in fluvial channel and floodplain environments.

The Scollard is usually classified as the uppermost formation of the Edmonton Group, although some early workers included it in the overlying Paskapoo Formation.{{Cite web|url= http://geoscan.ess.nrcan.gc.ca/cgi-bin/starfinder/0?path=geoscan.fl&id=fastlink&pass=&format=FLSHORTORG&search=R=215631|title= Paskapoo-Porcupine Hills Formation in western Alberta: Synthesis of regional geology and resource potential. Geological Survey of Canada, Open File 4679.|author=Hamblin, A.P.|year=2004|access-date=2013-08-01}} It is subdivided into an upper, coal-bearing member that consists of the Ardley coal zone, and a lower member that lacks significant coal. Neither member has been formally named.

File:Scollard Formation K-Pg boundary by Nick Longrich.jpg

The K-Pg boundary occurs at the base of the lowermost seam of Ardley coal zone, based on dinosaurian and microfloral evidence,Lerbekmo, J.F., Singh, C., Jarzen, D.M., and Russel, D.A. 1979. The Cretaceous-Tertiary boundary in south-central Alberta - a revision based on dinosaurian and microfloral evidence. Canadian Journal of Earth Science, 16: 325-330. as well as the presence of the terminal Cretaceous iridium anomaly.Lerbekmo, J.F. and St. Louis, R.M. 1985. The terminal Cretaceous iridium anomaly in the Red Deer Valley, Alberta. Canadian Journal of Earth Science, 23: 120-124. The upper member is therefore of early Danian age, while the lower member is of latest Maastrichtian age.

The Scollard Formation is present in the subsurface throughout much of southwestern Alberta,{{Cite web|url=http://www.ags.gov.ab.ca/publications/pubs.aspx?series=map|title=Bedrock Geology of Alberta. Alberta Geological Survey, Map 600|author=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.|year=2013|access-date=2013-08-13|url-status=dead|archive-url=https://web.archive.org/web/20130925225910/http://www.ags.gov.ab.ca/publications/pubs.aspx?series=map|archive-date=2013-09-25}} and it outcrops extensively along the banks of the Red Deer River in the area of Trochu. Both the upper and lower members thin from west to east. Thicknesses for each member range from more than {{convert|300|m|ft|-1}} near the foothills of the Canadian Rockies to less than {{convert|100|m|ft|-1}} near the outcrops in south-central Alberta.

The Scollard Formation rests disconformably on the Late Cretaceous Battle Formation in the southwestern Alberta plains, on the Wapiti Formation in the northwestern plains, and on the Brazeau Formation in the foothills. It is unconformably overlain by the Paskapoo Formation, and where the Paskapoo has been removed by erosion, the Scollard is exposed at surface or covered by Quaternary sediments.

The Scollard grades into the Willow Creek Formation in the southern Alberta plains and the Coalspur Formation in the Alberta foothills. The Ardley coal zone in the upper portion is equivalent to the lower part of the Coalspur coal zone of the Coalspur Formation,Langenberg, C.W., Berhane, H., Sweet, A.R., Marchioni, D. and Heamann, L.M. 2007. Regional correlations of the Ardley coal zone, Alberta. Alberta Geological Survey, Earth Sciences Report 2007-5, 21 p. and is correlated with the lower part of the Ravenscrag Formation of southern Saskatchewan, which is also coal bearing.{{Cite web|url= http://www.aer.ca/documents/catalog/TOF.pdf |title=Alberta Table of Formations; Alberta Energy Regulator|author= Alberta Geological Survey, 2013.|access-date=2016-06-20}} The Late Cretaceous member is equivalent in age to the Frenchman Formation of Saskatchewan, the Hell Creek Formation of Montana, and the Lance Formation of Wyoming .

File:Metasequoia occidentalis.jpg, upper Scollard Formation, central Alberta]]

The coal seams of the Ardley coal zone attain thicknesses in excess of {{convert|7|m|ft|-1}} in some areas. The zone is present at shallow depths and, in places, exposed at surface, along a trend between Red Deer and Edmonton. The coal is typically of sub-bituminous B to C rank, although more deeply buried Scollard coals farther to the west reach high-volatile bituminous rank. The Ardley coal has been mined in the Red Deer area, and is currently being mined west of Edmonton to fuel mine-mouth electric power generating stations.{{Cite web|url=http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch33/ch_33.html|title=The Geological Atlas of the Western Canada Sedimentary Basin, Chapter 33: Coal Resources of the Western Canada Sedimentary Basin|author=Mossop, G.D. and Shetsen, I., (compilers), Canadian Society of Petroleum Geologists|year=1994|access-date=2013-08-01|url-status=dead|archive-url=https://web.archive.org/web/20130930001329/http://www.ags.gov.ab.ca/publications/wcsb_atlas/a_ch33/ch_33.html|archive-date=2013-09-30}}

The Scollard Formation preserves the remains of vertebrates, especially dinosaurs and, rarely, mammals, as well as a wide range of plant fossils. The Scollard strata span the K-Pg boundary, therefore the lower member of the Scollard provides a record of the last of the dinosaurs, while the upper member records the dawn of the Age of Mammals after the K-Pg extinction event.

Plant fossils from the upper, early Paleocene member of the Scollard Formation include species of the ferns Botrychium, Woodwardia and Azolla; the conifers Metasequoia and Glyptostrobus; the monocot Limnobiophyllum (a relative of duckweeds), Sabalites geneseensis (similar to Serenoa repens); and the dicots Cercidiphyllum and Platanus. Leaf analysis of the Genesee flora estimated mean annual temperature at {{Convert|11|C|F}} with a cold month mean temperature of {{Convert|2.4|C|F}}.Chandrasekharam, A., 1974. Megafossil flora from the Genesee locality, Alberta, Canada. Palaeontographica, Abt. A, Band 147, 41 p.Christophel, D.C., 1976. Fossil floras from the Smoky Tower locality, Alberta, Canada. Palaeontographica, Abt. B, Band 157, 43 p.{{Cite journal |last=Greenwood |first=David R. |last2=West |first2=Christopher K. |date=2017-04-01 |title=A fossil coryphoid palm from the Paleocene of western Canada |url=https://www.sciencedirect.com/science/article/pii/S003466671630118X |journal=Review of Palaeobotany and Palynology |volume=239 |pages=55–65 |doi=10.1016/j.revpalbo.2016.12.002 |issn=0034-6667}} Graminidites, a Grass palynomorph occurs in the Maastrichtian Scollard Formation. The species, G. ulkapites, occurs at the initiation of a temperate climate in the area.{{Cite journal |last=SRIVASTAVA |first=SATISH K. |date=2011-10-01 |title=The occurrence of the fossil genus Graminidites in the Maastrichtian Scollard Formation, Alberta, Canada, and its palaeoecological and palaeogeographical significance |url=https://doi.org/10.1111/j.1095-8339.2011.01171.x |journal=Botanical Journal of the Linnean Society |volume=167 |issue=2 |pages=235–248 |doi=10.1111/j.1095-8339.2011.01171.x |issn=0024-4074}}

Crocodylian Albertosuchus, acanthomorph fish Lindoeichthys and unnamed esocid fish are known.{{Cite journal |last1=Wu |first1=Xiao-Chun |last2=Brinkman |first2=Donald B. |date=2015 |title=A new crocodylian (Eusuchia) from the uppermost Cretaceous of Alberta, Canada |url=http://dx.doi.org/10.1139/cjes-2014-0133 |journal=Canadian Journal of Earth Sciences |volume=52 |issue=8 |pages=590–607 |doi=10.1139/cjes-2014-0133 |bibcode=2015CaJES..52..590W |issn=0008-4077|url-access=subscription }}{{Cite journal |last1=Murray |first1=Alison M. |last2=Brinkman |first2=Donald B. |last3=Newbrey |first3=Michael G. |last4=Neuman |first4=Andrew G. |date=2020 |title=Earliest North American articulated freshwater acanthomorph fish (Teleostei: Percopsiformes) from Upper Cretaceous deposits of Alberta, Canada |url=https://www.cambridge.org/core/journals/geological-magazine/article/abs/earliest-north-american-articulated-freshwater-acanthomorph-fish-teleostei-percopsiformes-from-upper-cretaceous-deposits-of-alberta-canada/53C3A9C055107128FFDEFD986D4D4813 |journal=Geological Magazine |language=en |volume=157 |issue=7 |pages=1087–1096 |doi=10.1017/S0016756819001328 |bibcode=2020GeoM..157.1087M |s2cid=212927875 |issn=0016-7568|url-access=subscription }}{{Cite journal |last1=Brinkman |first1=Don |last2=Van Loon |first2=Lisa L. |last3=Banerjee |first3=Neil R. |date=2021 |title=3D Non-Destructive Identification of Fossil Fish from the Late Cretaceous of Alberta, Canada using Synchrotron Micro Computed Tomography |url=http://dx.doi.org/10.1017/s155192952100047x |journal=Microscopy Today |volume=29 |issue=2 |pages=26–31 |doi=10.1017/s155192952100047x |s2cid=232249820 |issn=1551-9295|url-access=subscription }}

Ornithomimus remains have been unearthed here.{{Cite journal |last1=Carpenter |first1=Kenneth |last2=Young |first2=D. Bruce |title=Late Cretaceous dinosaurs from the Denver Basin, Colorado |url=https://pubs.geoscienceworld.org/uwyo/rmg/article-abstract/37/2/237/87953/Late-Cretaceous-dinosaurs-from-the-Denver-Basin |journal=Rocky Mountain Geology |year=2002 |volume=37 |issue=2 |pages=237–254 |doi=10.2113/11 |bibcode=2002RMGeo..37..237C |via=GeoScienceWorld}} Two caenagnathid taxa, a large-bodied one similar to Caenagnathus and a small-bodied one similar to Leptorhynchos have been found.{{Cite journal |last1=Voris |first1=Jared T. |last2=Zelenitsky |first2=Darla K. |last3=Therrien |first3=François |date=2023-09-11 |title=Caenagnathids (Theropoda, Oviraptorosauria) from the uppermost Maastrichtian of the Scollard Formation of Alberta, Canada |journal=Cretaceous Research |volume=153 |pages=105708 |doi=10.1016/j.cretres.2023.105708 |s2cid=261779584 |issn=0195-6671}}

Fossil remains of the nodosaur Edmontonia and the chasmosaur Torosaurus have also been unearthed here and in the nearby areas.{{Cite journal |last1=Mallon |first1=Jordan C |last2=Holmes |first2=Robert B |last3=Bamforth |first3=Emily L |last4=Schumann |first4=Dirk |year=2022 |title=The record of Torosaurus (Ornithischia: Ceratopsidae) in Canada and its taxonomic implications |journal=Zoological Journal of the Linnean Society |volume=195 |issue=1 |pages=157–171 |doi=10.1093/zoolinnean/zlab120 |issn=0024-4082 |doi-access=free}} {{paleobiota-key-compact}}

• List of dinosaur-bearing rock formations

{{Reflist|3|refs=

"Introduction," Ryan and Russel (2001); page 279.

}}

• Ryan, M. J., and Russell, A. P., 2001. Dinosaurs of Alberta (exclusive of Aves): In: Mesozoic Vertebrate Life, edited by Tanke, D. H., and Carpenter, K., Indiana University Press, pp. 279–297.
• Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.): The Dinosauria, 2nd, Berkeley: University of California Press. 861 pp. {{ISBN|0-520-24209-2}}.

{{Western Canadian Sedimentary Basin|Central_Plains=yes}}

Category:Maastrichtian Stage of North America

Category:Cretaceous Alberta

Category:Cretaceous–Paleogene boundary

Category:Danian Stage

Category:Paleogene Alberta

Category:Sandstone formations of Canada

Category:Siltstone formations of Canada

Category:Shale formations of Canada

Category:Coal formations

Category:Coal in Canada

Category:Fluvial deposits

Category:Fossiliferous stratigraphic units of North America

Category:Paleontology in Alberta

Category:Western Canadian Sedimentary Basin