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Yahatinda Formation
The Yahatinda Formation is a geologic formation of Middle Devonian (Givetian) age in the southwestern part of the Western Canada Sedimentary Basin in the mountains of southwestern Alberta. Its type locality lies the on the eastern face of Wapiti Mountain above Ya-Ha-Tinda Ranch at the eastern edge of Banff National Park.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. . The Yahatinda contains a variety of Devonian fossils. Lithology The Yahatinda Formation includes both terrestrial river channel and littoral marine sediments. The channel deposits, which are well exposed at the type locality, consist of reddish, medium- to coarse-grained, cross-bedded dolomitic sandstones, siltstones, conglomerates and breccias. The channels contain eroded cobbles and boulders from the older underlying formati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimerophyte
Trimerophytopsida (or Trimeropsida) is a class of early vascular plants from the Devonian, informally called trimerophytes. It contains genera such as '' Psilophyton''. This group is probably paraphyletic, and is believed to be the ancestral group from which both the ferns and seed plants evolved. Different authors have treated the group at different taxonomic ranks using the names Trimerophyta, Trimerophytophyta, Trimerophytina, Trimerophytophytina and Trimerophytales. Taxonomy At first most of the early land plants other than the bryophytes (i.e. the polysporangiophytes) were placed in a single class Psilophyta, established in 1917 by Kidston and Lang. As additional fossils were discovered and described, it became apparent that the Psilophyta were not a homogeneous group of plants. In 1968 Banks first proposed splitting this taxon into three groups, which he put at the rank of subdivision; he clarified his proposal in 1975. One of the three groups was the Trimerophytina. The su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Locality (geology)
Type locality, also called type area, is the locality where a particular rock type, stratigraphic unit or mineral species is first identified. If the stratigraphic unit in a locality is layered, it is called a stratotype, whereas the standard of reference for unlayered rocks is the type locality. The term is similar to the term type site in archaeology or the term type specimen in biology. Examples of geological type localities Rocks and minerals * Aragonite: Molina de Aragón, Guadalajara, Spain * Autunite: Autun, France * Benmoreite: Ben More (Mull), Scotland * Blairmorite: Blairmore, Alberta, Canada * Boninite: Bonin Islands, Japan * Comendite: Comende, San Pietro Island, Sardinia * Cummingtonite: Cummington, Massachusetts * Dunite: Dun Mountain, New Zealand. * Essexite: Essex County, Massachusetts, US * Fayalite: Horta, Fayal Island, Azores, Portugal * Harzburgite: Bad Harzburg, Germany * Icelandite: Thingmuli (Þingmúli), Iceland * Ijolite: Iivaa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brazeau River
The Brazeau River is a river in western Alberta, Canada. It is a major tributary of the North Saskatchewan River. The river was named for Joseph Brazeau, a linguist associated with the Palliser Expedition. Course The river originates in the heights of the Canadian Rockies from Brazeau Lake (which is fed by creeks that flow from Coronet Glacier and the Queen Elizabeth Ranges) and flows east through the Rocky Mountains foothills until it merges into the North Saskatchewan River between Drayton Valley and Rocky Mountain House at Brazeau Forks. The upper course runs eastwards from Jasper National Park into Brazeau Canyon Wildland Provincial Park. The O'Chiese First Nation is established at the confluence with Nordegg River. The total length of the river is . The river, and various other local geographic features, were named after Joseph Brazeau, a Missouri-born fur trader working for the Hudson's Bay Company in the area between 1852 and 1864. Hydroelectric development ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 of the Canadian Cordillera, which is the northern segment of the North American Cordillera, the expansive system of interconnected mountain ranges between the Interior Plains and the Pacific Coast that runs northwest–southeast from central Alaska to the Isthmus of Tehuantepec in Mexico. Canada officially defines the Rocky Mountains system as the mountain chains east of the Rocky Mountain Trench extending from the Liard River valley in northern British Columbia to the Albuquerque Basin in New Mexico, not including the Mackenzie, Richardson and British Mountains/ Brooks Range in Yukon and Alaska (which are all included as the "Arctic Rockies" in the United States' definition of the Rocky Mountains system). The Canadian Rockies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 deposits are covered by soil and vegetation and cannot be seen or examined closely. However, in places where the overlying cover is removed through erosion or tectonic uplift, the rock may be exposed, or ''crop out''. Such exposure will happen most frequently in areas where erosion is rapid and exceeds the weathering rate such as on steep hillsides, mountain ridges and tops, river banks, and tectonically active areas. In Finland, glacial erosion during the last glacial maximum (ca. 11000 BC), followed by scouring by sea waves, followed by isostatic uplift has produced many smooth coastal and littoral outcrops. Bedrock and superficial deposits may also be exposed at the Earth's surface due to human excavations such as quarrying and bui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcrete
Caliche () is a sedimentary rock, a hardened natural cement of calcium carbonate that binds other materials—such as gravel, sand, clay, and silt. It occurs worldwide, in aridisol and mollisol soil orders—generally in arid or semiarid regions, including in central and western Australia, in the Kalahari Desert, in the High Plains of the western United States, in the Sonoran Desert, Chihuahuan Desert and Mojave Desert of North America, and in eastern Saudi Arabia at Al-Hasa. Caliche is also known as calcrete or kankar (in India). It belongs to the duricrusts. The term ''caliche'' is Spanish and is originally from the Latin ''calx'', meaning lime. Caliche is generally light-colored, but can range from white to light pink to reddish-brown, depending on the impurities present. It generally occurs on or near the surface, but can be found in deeper subsoil deposits, as well. Layers vary from a few inches to feet thick, and multiple layers can exist in a single location. A calich ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleosol
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 geology and paleontology, a paleosol is a former soil preserved by burial underneath either sediments (alluvium or loess) or volcanic deposits (volcanic ash), which in the case of older deposits have lithified into rock. In Quaternary geology, sedimentology, paleoclimatology, and geology in general, it is the typical and accepted practice to use the term "paleosol" to designate such "''fossil soils''" found buried within sedimentary and volcanic deposits exposed in all continents. In soil science the definition differs only slightly: ''paleosols'' are soils formed long ago that have no relationship in their chemical and physical characteristics to the present-day climate or vegetation. Such soils are found within extremely old continental ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrite
Micrite is a limestone constituent formed of calcareous particles ranging in diameter up to four μm formed by the recrystallization of lime mud. Flügel, Erik, ''Microfacies of Carbonate Rocks: Analysis, Interpretation and Application,'' Springer, pp 74-94, 2004 The term was coined in 1959 by Robert Folk for his carbonate rock classification system. Micrite is derived from MICRocrystalline calcITE. In the Folk classification micrite is a carbonate rock dominated by fine-grained calcite Calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on the Mohs scale of mineral hardness, based on scra .... Carbonate rocks that contain fine-grained calcite in addition to allochems are named ''intramicrite'', ''oomicrite'', ''biomicrite'' or ''pelmicrite'' under the Folk classification depending on the dominant allochem. Micrite is lime mud, carbon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Breccias
Breccia () is a rock composed of large angular broken fragments of minerals or rocks cemented together by a fine-grained matrix. The word has its origins in the Italian language, in which it means "rubble". A breccia may have a variety of different origins, as indicated by the named types including sedimentary breccia, tectonic breccia, igneous breccia, impact breccia, and hydrothermal breccia. A megabreccia is a breccia composed of very large rock fragments, sometimes kilometers across, which can be formed by landslides, impact events, or caldera collapse. Types Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. These indicate that the gravel was deposited very close to its source area, since otherwise t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conglomerate (geology)
Conglomerate () is a clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts. A conglomerate typically contains a matrix of finer-grained sediments, such as sand, silt, or clay, which fills the interstices between the clasts. The clasts and matrix are typically cemented by calcium carbonate, iron oxide, silica, or hardened clay. Conglomerates form by the consolidation and lithification of gravel. They can be found in sedimentary rock sequences of all ages but probably make up less than 1 percent by weight of all sedimentary rocks. In terms of origin and depositional mechanisms, they are closely related to sandstones and exhibit many of the same types of sedimentary structures, e.g., tabular and trough cross-bedding and graded bedding.Boggs, S. (2006) ''Principles of Sedimentology and Stratigraphy.'', 2nd ed. Prentice Hall, New York. 662 pp. Friedman, G.M. (2003) ''Classification of sediments and sedimentary rocks ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cross-bedding
In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. The original depositional layering is tilted, such tilting not being the result of post-depositional deformation. Cross-beds or "sets" are the groups of inclined layers, which are known as cross-strata. Cross-bedding forms during deposition on the inclined surfaces of bedforms such as ripples and dunes; it indicates that the depositional environment contained a flowing medium (typically water or wind). Examples of these bedforms are ripples, dunes, anti-dunes, sand waves, hummocks, bars, and delta slopes.Collinson, J.D., Thompson, D.B., 1989, Sedimentary Structures (2nd ed): Academic Division of Unwin Hyman Ltd, Winchester, MA, XXX p. Environments in which water movement is fast enough and deep enough to develop large-scale bed forms fall int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Littoral Zone
The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas that are permanently submerged — known as the ''foreshore'' — and the terms are often used interchangeably. However, the geographical meaning of ''littoral zone'' extends well beyond the intertidal zone to include all neritic waters within the bounds of continental shelves. Etymology The word ''littoral'' may be used both as a noun and as an adjective. It derives from the Latin noun ''litus, litoris'', meaning "shore". (The doubled ''t'' is a late-medieval innovation, and the word is sometimes seen in the more classical-looking spelling ''litoral''.) Description The term has no single definition. What is regarded as the full extent of the littoral zone, and the way the littoral zone is divided into subregions, varies in dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
