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Porcupine Hills Formation
The Porcupine Hills Formation is a Stratigraphy, stratigraphic unit of middle to late Paleocene Geochronology, age in the Western Canadian Sedimentary Basin, 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. Lithology The Porcupine Hills Formation is composed primarily of shale, mudstones, siltstones and sandstones. The sediments were derived from the Canadian Cordillera during tectonic uplift and erosion in the late stages of the Laramide Orogeny, and were transported eastward by river systems and deposited in fluvial and floodplain environments. The mudstones are characterized by well-developed paleosols and caliche nodules, and the sandstones are cross-bedding, cross-bedded and cemented with calcite. In contrast to the Paskapoo Formation, an equivalent formation farther to the north, there are no coaly beds. This has given rise to the hypothesis that duri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological 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 exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 northern part of the North American Cordillera. The mountain ranges in this region were covered during the Pleistocene by the Cordilleran Ice Sheet, the extent of which gives perspective on the geographic extent of this region. The cordillera extends from the Alaska's Brooks and Alaska Ranges, southeast through most of the Yukon and British Columbia as well as the southwestern fringe of Northwest Territories and Alberta (bordered by the Mackenzie-Peel/Liard River basin and the Canadian Prairies in the east), to stretch its margin beyond the Canada–United States border with five extensive lobes reaching into the mountain valleys of Montana and Washington (state), Washington.D. B. Booth. (1987). Timing and processes of deglaciation along th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion Surface
In geology and geomorphology, an erosion surface is a surface of rock or regolith that was formed by erosion and not by construction (e.g. lava flows, sediment deposition) nor fault displacement. Erosional surfaces within the stratigraphic record are known as unconformities, but not all unconformities are buried erosion surfaces. Erosion surfaces vary in scale and can be formed on a mountain range or a rock. Particularly large and flat erosion surfaces receive the names of peneplain, paleoplain, planation surface or pediplain. An example of erosion surface is road surface erosion which is caused by natural and anthropogenic factors. Erosion surface can be measured through direct, contact measurement methods and indirect, non-contact measurement methods. Road surface erosion Just like mountains and rocks, erosion can also occur on unsealed roads due to natural and anthropogenic factors. Road surface erosion could be caused by snowfall, rainfall and wind. The material an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calgary
Calgary ( ) is the largest city in the western Canadian province of Alberta and the largest metro area of the three Prairie Provinces. As of 2021, the city proper had a population of 1,306,784 and a metropolitan population of 1,481,806, making it the third-largest city and fifth-largest metropolitan area in Canada. Calgary is situated at the confluence of the Bow River and the Elbow River in the south of the province, in the transitional area between the Rocky Mountain Foothills and the Canadian Prairies, about east of the front ranges of the Canadian Rockies, roughly south of the provincial capital of Edmonton and approximately north of the Canada–United States border. The city anchors the south end of the Statistics Canada-defined urban area, the Calgary–Edmonton Corridor. Calgary's economy includes activity in the energy, financial services, film and television, transportation and logistics, technology, manufacturing, aerospace, health and wellness, reta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bow River
The Bow River is a river in Alberta, Canada. It begins within the Canadian Rocky Mountains and winds through the Alberta foothills onto the prairies, where it meets the Oldman River, the two then forming the South Saskatchewan River. These waters ultimately flow through the Nelson River into Hudson Bay. The Bow River runs through the city of Calgary, taking in the Elbow River at the historic site of Fort Calgary near downtown. The Bow River pathway, developed along the river's banks, is considered a part of Calgary's self-image. First Nations made varied use of the river for sustenance before settlers of European origin arrived, such as using its valleys in the buffalo hunt. The name ''Bow ''refers to the reeds that grew along its banks and were used by the First Nations to make bows; the Blackfoot language name for the river is , meaning "river where bow reeds grow". The river is an important source of water for irrigation and drinking water. Between the years 1910 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canada–United States Border
The border between Canada and the United States is the longest international border in the world. The terrestrial boundary (including boundaries in the Great Lakes, Atlantic, and Pacific coasts) is long. The land border has two sections: Canada's border with the contiguous United States to its south, and with the U.S. state of Alaska to its west. The bi-national International Boundary Commission deals with matters relating to marking and maintaining the boundary, and the International Joint Commission deals with issues concerning boundary waters. The agencies currently responsible for facilitating legal passage through the international boundary are the Canada Border Services Agency (CBSA) and U.S. Customs and Border Protection (CBP). History 18th century The Treaty of Paris of 1783 ended the American Revolutionary War between Great Britain and the United States. In the second article of the Treaty, the parties agreed on all boundaries of the United States, including, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterton River
Waterton Lake is a mountain lake in southern Alberta, Canada and northern Montana, United States. The lake is composed of two bodies of water, connected by a shallow channel known locally as the Bosporus. The two parts are referred to as Middle Waterton Lake, and Upper Waterton Lake, the latter of which is divided by the Canada–United States border with Canada containing about two thirds of the lake while the Southern third falls in the United States. The Boundary Commission Trail ends at the lake as the last border marker was placed there on 8 August 1874. The United States Geological Survey gives the geocoordinates of for Upper Waterton Lake. Lower Waterton Lake is north of Middle Waterton Lake and is separated by a channel known as the Dardanelles. The northern, lower end of the main lake lies in Waterton Lakes National Park while the upper, southern part of the lake is located in Glacier National Park. In 1979, UNESCO established the ''Waterton Biosphere Reserve'' t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semi-arid Climate
A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes. Defining attributes of semi-arid climates A more precise definition is given by the Köppen climate classification, which treats steppe climates (''BSk'' and ''BSh'') as intermediates between desert climates (BW) and humid climates (A, C, D) in ecological characteristics and agricultural potential. Semi-arid climates tend to support short, thorny or scrubby vegetation and are usually dominated by either grasses or shrubs as it usually can't support forests. To determine if a location has a semi-arid climate, the precipitation threshold must first be determined. The method used to find the precipitation threshold (in millimeters): *multip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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" in Cree). 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 J.B. Tyrrell in 1887.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 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. Lithology and environment of deposition The Paskapoo Formation is of fluvial origin and consists primarily of sandstones, siltstones and mudstones, with les ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 scratch hardness comparison. Large calcite crystals are used in optical equipment, and limestone composed mostly of calcite has numerous uses. Other polymorphs of calcium carbonate are the minerals aragonite and vaterite. Aragonite will change to calcite over timescales of days or less at temperatures exceeding 300 °C, and vaterite is even less stable. Etymology Calcite is derived from the German ''Calcit'', a term from the 19th century that came from the Latin word for lime, ''calx'' (genitive calcis) with the suffix "-ite" used to name minerals. It is thus etymologically related to chalk. When applied by archaeologists and stone trade professionals, the term alabaster is used not just as in geology and mineralogy, where it is ... [...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] |
Caliche
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 cali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
