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Verulam Formation
The Verulam Formation is a Formation (geology), geologic formation and Lagerstätte in Ontario, Canada. It preserves fossils dating back to the Katian stage of the Ordovician Period (geology), period, or Shermanian to Chatfieldian in the regional stratigraphy. Description The Verulam Formation belongs to the Simcoe Group in South-central Ontario and to the Trenton Group in Southwestern Ontario. Within the Simcoe Group, it overlies the Bobcaygeon Formation. Both the Bobcaygeon and Verulam Formations are composed of bioclastic wackestones, grainstones, and packstones interbedded with calcareous shales and siltstones. The Verulam contains more shale than the underlying Bobcaygeon Formation. Several hardgrounds have been documented in detail from the upper Bobcaygeon and lower Verulam. The paleoenvironments in which the Bobcaygeon and Verulam Formations were deposited have been interpreted as a proximal carbonate shelf that ranged in depth and proximity from shoal to shallow shelf in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kawartha Lakes
Kawartha Lakes (Canada 2021 Census, 2021 population: 79,247) is a List of municipalities in Ontario , single-tier municipality in Central Ontario, Canada. Though structured as a single-tier municipality, Kawartha Lakes is the size of a typical Ontario county and is mostly rural. It is the second largest single-tier municipality in Ontario by land area (after Greater Sudbury). The main population centres are the communities of Lindsay, Ontario, Lindsay (population: 22,367), Bobcaygeon (population: 3,576), Fenelon Falls (population: 2,490), Omemee, Ontario, Omemee (population: 1,060) and Woodville, Ontario, Woodville (population: 718). History The Kawartha Lakes area is situated on the traditional territory of the Anishinaabeg, Huron-Wendat Nation, Huron-Wendat and more recently, the Haudenosaunee peoples. The city's name is from the Kawartha Lakes (Ontario), Kawartha Lakes. ''Kawartha'' is an anglicization of ''Ka-wa-tha'' (from ''Ka-wa-tae-gum-maug'' or ''Gaa-waategamaag''), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Katian
The Katian is the second stage of the Upper Ordovician. It is preceded by the Sandbian and succeeded by the Hirnantian Stage. The Katian began million years ago and lasted for about 7.6 million years until the beginning of the Hirnantian million years ago. During the Katian the climate cooled which started the Late Ordovician glaciation. Naming The name Katian is derived from Katy Lake ( Atoka County, Oklahoma, United States). GSSP The GSSP of the Katian Stage is the Black Knob Ridge Section in southeastern Oklahoma (United States). It is an outcrop of the Womble Shale and the Bigfork Chert, the latter containing the lower boundary of the Katian. The lower boundary is defined as the first appearance datum of the graptolite Graptolites are a group of colonial animals, members of the subclass Graptolithina within the class Pterobranchia. These filter-feeding organisms are known chiefly from fossils found from the Middle Cambrian ( Miaolingian, Wuliuan) through t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossilworks
Fossilworks was a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database, a large relational database assembled by hundreds of paleontologists from around the world. History Fossilworks was created in 1998 by John Alroy and housed at Macquarie University Macquarie University ( ) is a Public university, public research university in Sydney, New South Wales, Australia. Founded in 1964 by the New South Wales Government, it was the third university to be established in the Sydney metropolitan area. .... It included many analysis and data visualization tools formerly included in the Paleobiology Database.{{cite web, title=Frequently asked questions, url=http://www.fossilworks.org/cgi-bin/bridge.pl?page=FAQ, publisher=Fossilworks, access-date=17 December 2021, archive-date=18 May 2022, archive-url=https://web.archive.org/web/20220518205516/http://www.fossilworks.org/cgi-bin/bridge.pl?page=FAQ, url-status=dead Fossilworks was sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shoal
In oceanography, geomorphology, and Earth science, geoscience, a shoal is a natural submerged ridge, bank (geography), bank, or bar that consists of, or is covered by, sand or other unconsolidated material, and rises from the bed of a body of water close to the surface or above it, which poses a danger to navigation. Shoals are also known as sandbanks, sandbars, or gravelbars. Two or more shoals that are either separated by shared crest and trough, troughs or interconnected by past or present sedimentary and hydrographic processes are referred to as a shoal complex.Neuendorf, K.K.E., J.P. Mehl Jr., and J.A. Jackson, eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological Institute. 779 pp. The term ''shoal'' is also used in a number of ways that can be either similar to, or quite different from, how it is used in geologic, geomorphic, and oceanographic literature. Sometimes, the term refers to either any relatively shallow place in a stream ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hardground
Carbonate hardgrounds are surfaces of synsedimentarily cemented carbonate layers that have been exposed on the seafloor (Wilson and Palmer, 1992). A hardground is essentially, then, a lithified seafloor. Ancient hardgrounds are found in limestone sequences and distinguished from later-lithified sediments by evidence of exposure to normal marine waters. This evidence can consist of encrusting marine organisms (especially bryozoans, oysters, barnacles, cornulitids, hederelloids, microconchids and crinoids), borings of organisms produced through bioerosion, early marine calcite cements, or extensive surfaces mineralized by iron oxides or calcium phosphates (Palmer, 1982; Bodenbender et al., 1989; Vinn and Wilson, 2010; Vinn and Toom, 2015). Modern hardgrounds are usually detected by sounding in shallow water or through remote sensing techniques like side-scan sonar. Carbonate hardgrounds often host a unique fauna and flora adapted to the hard surface. Organisms usually ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siltstones
Siltstone, also known as aleurolite, is a clastic sedimentary rock that is composed mostly of silt Silt is granular material of a size between sand and clay and composed mostly of broken grains of quartz. Silt may occur as a soil (often mixed with sand or clay) or as sediment mixed in suspension (chemistry), suspension with water. Silt usually .... It is a form of mudrock with a low clay mineral content, which can be distinguished from shale by its lack of fissility (geology), fissility. Although its permeability and porosity is relatively low, siltstone is sometimes a tight gas reservoir rock, an Unconventional (oil & gas) reservoir, unconventional reservoir for natural gas that requires hydraulic fracturing for economic gas production. Siltstone was prized in ancient Egypt for manufacturing statuary and cosmetic palettes. The siltstone quarried at Wadi Hammamat was a hard, fine-grained siltstone that resisted flaking and was almost ideal for such uses. Description Ther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcareous
Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime (mineral), lime or being chalky. The term is used in a wide variety of Science, scientific disciplines. In zoology ''Calcareous'' is used as an adjectival term applied to anatomical structures which are made primarily of calcium carbonate, in animals such as gastropods, i.e., snails, specifically in relation to such structures as the operculum (gastropod), operculum, the clausilium, and the love dart. The term also applies to the calcium carbonate Test (biology), tests of, often, more-or-less microscopic Foraminifera. Not all tests are calcareous; diatoms and radiolaria have siliceous tests. The molluscs are calcareous organisms, as are the Calcarea, calcareous sponges (Calcarea), that have spicules which are made of calcium carbonate. Additionally, reef-building corals, or Scleractinia, are calcareous organisms that form their rigid skeletal structure th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Packstone
Under the Dunham classification (Dunham, 1962Dunham, R.J. (1962) Classification of carbonate rocks according to depositional texture. In: Classification of Carbonate Rocks (Ed. W.E. Ham), Am. Assoc. Pet. Geol. Mem., 1, 108–121.) system of limestones, a packstone is defined as a grain-supported carbonate rock that contains 1% or more mud-grade fraction. This definition has been clarified by Lokier and Al Junaibi (2016) as ''a carbonate-dominated lithology containing carbonate mud (2 mm''. The identification of packstone A study of the adoption and use of carbonate classification systems by Lokier and Al Junaibi (2016) identified three common problems encountered when describing a packstone: * Failure to identify the fabric as supported by the sand grade grain-size fraction - resulting in misidentification as wackestone Under the Dunham classification (Dunham, 1962Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture. In: W.E. Ham (Ed.), Class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grainstone
Under the Dunham classification (Dunham, 1962) system of limestones, a grainstone is defined as a grain-supported carbonate rock that contains less than 1% mud-grade material. This definition has recently been clarified as ''a carbonate-dominated rock that does not contain any carbonate mud and where less than 10% of the components are larger than 2 mm.'' The spaces between grains may be empty (pores) or filled by cement. The identification of grainstone The presence of any primary carbonate mud precludes a classification of grainstone. A study of the use of carbonate classification systems by Lokier and Al Junaibi highlighted that the most common source of confusion in the classification of grainstone was to misidentify fine-grained internal micrite, generated by in-situ processes, as clay–silt grade sediment - thus resulting in the misidentification of grainstone as packstone. Failure to correctly determine the size and abundance of component grains greater than two millime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wackestone
Under the Dunham classification (Dunham, 1962Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture. In: W.E. Ham (Ed.), Classification of Carbonate Rocks. American Association of Petroleum Geologists Memoir. American Association of Petroleum Geologists, Tulsa, Oklahoma, pp. 108–121.) system of limestones, a wackestone is defined as a mud-supported carbonate rock Carbonate rocks are a class of sedimentary rocks composed primarily of carbonate minerals. The two major types are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3), and Dolomite (rock), dolomite rock (also kn ... that contains greater than 10% grains. Most recently, this definition has been clarified as ''a carbonate-dominated rock in which the carbonate mud (2 mm)''. The identification of wackestone A study of the adoption and use of carbonate classification systems by Lokier and Al Junaibi (2016) highlighted that the most common problem enc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southwestern Ontario
Southwestern Ontario (census population 2,796,367 in 2021) is a secondary region of Southern Ontario in the Provinces and territories of Canada, Canadian province of Ontario. It occupies most of the Ontario Peninsula, bounded by Lake Huron (including Georgian Bay) to the north and northwest, the St. Clair River, Lake St. Clair, and Detroit River to the west, and Lake Erie to the south. To the east, on land, Southwestern Ontario is bounded by Central Ontario and the Golden Horseshoe. It borders the United States via Michigan. Definitions Southwestern Ontario is often not consistently defined. In certain documents, the Government of Ontario classifies municipalities along the eastern side of Southwestern Ontario near the Grand River (Ontario), Grand River, including County of Brant, Brant County, Regional Municipality of Waterloo, Waterloo Region, and Wellington County, Ontario, Wellington County, as part of the Greater Golden Horseshoe region that surrounds western Lake Ontario, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
