Whitemud Formation
   HOME

TheInfoList



OR:

The Whitemud Formation is a
geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...
of
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 ...
(
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 ...
) age 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 ...
. it is present through the plains 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 ...
, southeastern
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 south-central Alberta. Named by N.B. Davis in 1918, the formation is characterized by white kaolinitic
clay Clay is a type of fine-grained natural soil material containing clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4). Clays develop plasticity when wet, due to a molecular film of water surrounding the clay par ...
and is a source of high-quality
refractory In materials science, a refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractories are polycrystalline, polyphase, ...
clay.Lerbekmo, J.F. 1985. Magnetostratigraphic and biostratigraphic correlations of Maastrichtian to early Paleocene strata between south-central Alberta and southwestern Saskatchewan. Bulletin of Canadian Petroleum Geology, vol. 33, no. 2, p. 213-266. The type locality has been designated as Dempster's clay pit northwest of
Eastend Eastend is a town in south-west part of the Canadian province of Saskatchewan, situated approximately north of the Montana border and east of the Alberta border. The town is best known for the nearby discovery of a ''Tyrannosaurus rex'' s ...
, Saskatchewan.Kupsch, W.O. 1956. The Frenchman Formation of the eastern Cypress Hills, Saskatchewan. Geological Society of America Bulletin, vol. 6a, p. 413-420. Although
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 are generally lacking in the Whitemud Formation, in southern Saskatchewan the Whitemud contains coprolites (fossilized
feces Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...
) and fossilized
intestine The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...
s of
fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...
.


Lithology

In most areas the formation can be subdivided into three units: * Lower: Medium-grained arkosic and kaolinitic
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) ...
s with trough cross-bedding. * Middle: Brown fissile carbonaceous
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 ...
s and
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, with thin
lignite Lignite, often referred to as brown coal, is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat. It has a carbon content around 25–35%, and is considered the lowest rank of coal due to its relatively low heat ...
beds. * Upper: Clays and siltstones, with some thinner, tabular units of simple and planar cross-bedded kaolinitic sandstones.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. . In southwestern Alberta around the
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 ...
and
Oldman River The Oldman River is a river in southern Alberta, Canada. It flows roughly west to east from the Rocky Mountains, through the communities of Fort Macleod, Lethbridge, and on to Grassy Lake, where it joins the Bow River to form the South Saskatche ...
s, the middle carbonaceous shale unit is absent and the formation consists of white-weathering, cross-bedded kaolinitic sandstones interbedded with white- to cream-weathering silty and sandy clay.


Environment of Deposition

Sedimentology Sedimentology encompasses the study of modern sediments such as sand, silt, and clay, and the processes that result in their formation (erosion and weathering), transport, deposition and diagenesis. Sedimentologists apply their understanding of mo ...
and
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 indicate that the Whitemud sediments accumulated in
river channel In physical geography, a channel is a type of landform consisting of the outline of a path of relatively shallow and narrow body of water or of other fluids (e.g., lava), most commonly the confine of a river, river delta or strait. The word is ...
s, low-gradient
stream A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...
s, and shallow
lake A lake is an area filled with water, localized in a basin, surrounded by land, and distinct from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although, like the much large ...
s and
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 ...
s on a low-lying coastal plain. Its kaolinite was produced by intense chemical weathering that altered the original
feldspar Feldspars are a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the ''plagioclase'' (sodium-calcium) feldsp ...
content to kaolinite during and after deposition.


Economic resources

Kaolinite-rich clays have been quarried from the Whitemud Formation since before 1920 and are used in the manufacture of stoneware products ranging from pottery to sewer pipes.Lindoe, L.O. 1965. Ceramic clays of the Cypress Hills. Alberta Society of Petroleum Geologists, 15th Annual Field Trip Guidebook, Part 1, Cypress Hills plateau, p. 210-225.


Paleontology

Plant fossils and palynomorphs found in the carbonaceous shales indicate the presence of
aquatic plant Aquatic plants are plants that have adapted to living in aquatic environments (saltwater or freshwater). They are also referred to as hydrophytes or macrophytes to distinguish them from algae and other microphytes. A macrophyte is a plant that ...
s such as water lilies, as well as
tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
s and
shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...
s related to
figs The fig is the edible fruit of ''Ficus carica'', a species of small tree in the flowering plant family Moraceae. Native to the Mediterranean and western Asia, it has been cultivated since ancient times and is now widely grown throughout the world ...
, hickories and
redwood Sequoioideae, popularly known as redwoods, is a subfamily of coniferous trees within the family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affini ...
s. Coprolites provide the only evidence of
vertebrate Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, ...
s. In southern Saskatchewan the formation contains scattered coprolites that represent
feces Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...
of fish, most probably
sturgeon Sturgeon is the common name for the 27 species of fish belonging to the family Acipenseridae. The earliest sturgeon fossils date to the Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretace ...
s. The feces have been preserved due to the replacement of the original fecal material by goethite, siderite and other iron
mineral In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.John P. Rafferty, ed. ( ...
s. They typically range in length from about 2 to 10 cm (1 to 4 in), although specimens as long as 23 cm (9 in) have been reported. A variety of coiled and uncoiled morphologies have been described, and some
spiral In mathematics, a spiral is a curve which emanates from a point, moving farther away as it revolves around the point. Helices Two major definitions of "spiral" in the American Heritage Dictionary are:intestine The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans ...
s containing feces that were unexpelled when the fishes died.Broughton, P.L., Simpson, F. and Whittaker, S.H. 1977. Late Cretaceous coprolites from southern Saskatchewan: Comments on excretion plasticity and ichnological nomenclature. Bulletin of Canadian Petroleum Geology, vol. 25, no. 5, p. 1097-1099.Broughton, P.L., Simpson, F. and Whittaker, S.H. 1978. Late Cretaceous coprolites from western Canada. Palaeontology, vol. 21, pt. 2, p. 443-453, plates 43 & 44.


Relationship to Other Units

The Whitemud Formation is part of the
Edmonton Group Within the earth science of geology, the Edmonton Group is a Late Cretaceous (Campanian stage) to early Paleocene stratigraphic unit of the Western Canada Sedimentary Basin in the central Alberta plains. It was first described as the Edmonton Forma ...
. It rests
conformably Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are primarily igne ...
on the
Eastend Formation The Eastend Formation is a stratigraphical unit of Maastrichtian age in the Western Canadian Sedimentary Basin. It takes its name from the town of Eastend, Saskatchewan, and was first described in outcrop around the settlement by L.S. Russell in ...
in Saskatchewan and in the Cypress Hills area; on the Horseshoe Canyon Formation in the Drumheller area; and on the St. Mary River Formation in the
Oldman River The Oldman River is a river in southern Alberta, Canada. It flows roughly west to east from the Rocky Mountains, through the communities of Fort Macleod, Lethbridge, and on to Grassy Lake, where it joins the Bow River to form the South Saskatche ...
area. In southeastern Saskatchewan it is
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 ...
overlain by the Frenchman Formation; and in all other areas it is conformably overlain by the
Battle Formation The Battle Formation is a Formation (geology), geologic formation of Late Cretaceous (Maastrichtian) age in the Western Canadian Sedimentary Basin, Western Canada Sedimentary Basin. It is present throughout much of the central Alberta plains, wh ...
.


References

{{reflist Geologic formations of Canada Maastrichtian Stage of North America Cretaceous Alberta Stratigraphy of Alberta Stratigraphy of Saskatchewan