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Geology Of Gotland
Gotland is made up of a sequence of sedimentary rocks of a Silurian age, dipping to the south-east. The main Silurian succession of limestones and shales comprises thirteen units spanning of stratigraphic thickness, being thickest in the south, and overlies a thick Ordovician sequence. Precambrian shield rocks that underlie these sediments are found 400 to 500 meters sea level. Sedimentary rocks cropping out in Gotland were deposited in a shallow, hot and salty sea, on the edge of an equatorial continent. The water depth never exceeded , and shallowed over time as bioherm detritus, and terrestrial sediments, filled the basin. Reef growth started in the Llandovery, when the sea was deep, and reefs continued to dominate the sedimentary record. Some sandstones are present in the youngest rocks towards the south of the island, which represent sand bars deposited very close to the shore line. The lime rocks have been weathered into characteristic karstic rock formations known a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rauk
A rauk is a column-like landform in Sweden and Norway, often equivalent to a stack. Rauks often occur in groups called "raukfält" or "rauk fields". The limestone rauks of Gotland in the Baltic Sea are among the best known examples. Sweden Rauks are common on the island of Gotland, Sweden and on the smaller islands belonging to Gotland County. Fårö island in Gotland, is particularly rich in rauks. While Fårö is on the northern end of Gotland Holmhällars raukfält at Vamlingbo in the southern end of Gotland is also rich in rauks. Rauks in Gotland often occur in groups or fields, so-called ''raukfält''. Rauks can be found both near Gotland's many cliffs or far away from these. Other localities with rauks include Byrum on northwestern Öland neighboring Blå Jungfrun island, Hovs Hallar and Kullaberg in northwestern Scania and Härnön in northern Sweden's High Coast. Rauks on Öland are made up of limestone. A few rauks are located in the Scandinavian Mountains in n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sundre Formation
Sundre is a town in central Alberta, Canada that is surrounded by Mountain View County. It is approximately northwest of Calgary on the Cowboy Trail in the foothills of the Canadian Rockies. Sundre takes its name from a town in Norway, the original home of Nels T. Hagen, the town's first postmaster. History Sundre's first postmaster, Nels T. Hagen, arrived in 1906. Sundre incorporated as a village in 1950 and then as a town in 1956. Demographics In the 2021 Census of Population conducted by Statistics Canada, the Town of Sundre had a population of 2,672 living in 1,187 of its 1,270 total private dwellings, a change of from its 2016 population of 2,729. With a land area of , it had a population density of in 2021. In the 2016 Census of Population conducted by Statistics Canada, the Town of Sundre recorded a population of 2,729 living in 1,188 of its 1,256 total private dwellings, a change from its 2011 population of 2,610. With a land area of , it had a population de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ludlow Epoch
In the geological timescale, the Ludlow Epoch (from 427.4 ± 0.5 million years ago to 423.0 ± 2.3 million years ago) occurred during the Silurian Period, after the end of the Homerian Age. It is named for the town of Ludlow in Shropshire, England. The Ludlow Epoch is subdivided into two stages: Gorstian and Ludfordian. Paleontology Arthropods See also *Ludlow Group References Ludlow epoch, Silurian geochronology, *03 Geological epochs Ludlow first appearances, {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maurits Lindström
Maurits Lindström (10 May 1932 – 14 November 2009) was a Swedish geologist and paleontologist. Lindströms initial work was divided among two topics conodont paleontology and the structural geology of the Scandinavian Caledonides in Lappland. In 1970, he described the conodont families Cordylodontidae, Gondolellidae, Proconodontidae and Rhipidognathidae. In 1971, he described the conodont genera '' Baltoniodus'', '' Microzarkodina'' and ''Paracordylodus''.Vom Anfang, Hochstand und Ende eines Epikontinentalmeeres. Maurits Lindström, Geologische Rundschau, March 1971, Volume 60, Issue 2, pages 419-438, Lindström published conodont studies up to 1987 after which he only supervised students working with conodonts. In the late 1980s Lindström begun to study ancient impact craters in the Fennoscandian Shield. His studies have confirmed earlier speculations that Tvären and Lockne are craters. Awards and tributes In 1985 he became member of the Royal Swedish Academy of Scienc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Lundqvist (geologist)
Thomas Lundqvist (1932) is a Swedish geologist. He is son of Gösta Lundqvist and brother of Jan Lundqvist, both of whom are geologists. Thomas Lundqvist worked at Geological Survey of Sweden from 1962 onwards and was professor at the University of Gothenburg from 1986 to 1989. In 1968 he obtained a Ph.D. degree in geology at Stockholm University with the thesis ''Precambrian Geology of the Los-Hamra Region, Central Sweden''. Since 1996 Thomas Lundqvist has been member of the Finnish Society of Sciences and Letters The Finnish Society of Sciences and Letters is a Finnish academy for natural sciences, social sciences and humanities. It is known in Latin as Societas Scientiarum Fennica, in Swedish as Finska Vetenskaps-Societeten, and in Finnish as Suomen Tiede .... References {{DEFAULTSORT:Lundqvist, Thomas 20th-century Swedish geologists 1932 births Living people ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Lundqvist
Jan Lundqvist (born 4 August 1926) is a Swedish geologist. He is son of Gösta Lundqvist and brother of Thomas Lundqvist, both of whom are geologists. Jan Lundqvist worked at Geological Survey of Sweden from 1951 to 80 and obtained a Ph.D. degree in Quaternary geology at Stockholms högskola in 1958, becoming in also a teacher in that institution. Jan Lundqvist is considered among the foremost authorities on the Quaternary geology of Fennoscandia __NOTOC__ Fennoscandia (Finnish language, Finnish, Swedish language, Swedish and no, Fennoskandia, nocat=1; russian: Фенноскандия, Fennoskandiya) or the Fennoscandian Peninsula is the geographical peninsula in Europe, which includes .... References External linksStockholms universitet - Jan Lundqvist {{DEFAULTSORT:Lundqvist, Jan Stockholm University alumni 20th-century Swedish geologists Quaternary geologists 1926 births Living people Members of the Royal Swedish Academy of Sciences ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burgsvik Beds Map
Burgsvik is a locality situated in Öja in the Swedish island of Gotland with 350 inhabitants in 2014. Burgsvik lies in the southern part of the island of Gotland. The Burgsvik beds are a geological sequence found there. References External links Objects from Burgsvik at the Digital Museumby Nordic Museum The Nordic Museum ( sv, Nordiska museet) is a museum located on Djurgården, an island in central Stockholm, Sweden, dedicated to the cultural history and ethnography of Sweden from the early modern period (in Swedish history, it is said t ... * Populated places in Gotland County {{Gotland-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lau Event
The Lau event was the last of three relatively minor mass extinctions (the Ireviken, Mulde, and Lau events) during the Silurian period. It had a major effect on the conodont fauna, but barely scathed the graptolites, though they suffered an extinction very shortly thereafter termed the Kozlowskii event that some authors have suggested was coeval with the Lau event and only appears asynchronous due to taphonomic reasons. It coincided with a global low point in sea level caused by glacioeustasy and is closely followed by an excursion in geochemical isotopes in the ensuing late Ludfordian faunal stage and a change in depositional regime. Biological impact The Lau event started at the beginning of the late Ludfordian, a subdivision of the Ludlow stage, about . Its strata are best exposed in Gotland, Sweden, taking its name from the parish of Lau. Its base is set at the first extinction datum, in the Eke beds, and despite a scarcity of data, it is apparent that most major groups suf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mulde Event
The Mulde event was an anoxic event, and marked the second of three relatively minor mass extinctions (the Ireviken, Mulde, and Lau events) during the Silurian period. It coincided with a global drop in sea level, and is closely followed by an excursion in geochemical isotopes. Its onset is synchronous with the deposition of the Fröel Formation in Gotland. Perceived extinction in the conodont Conodonts (Greek ''kōnos'', "cone", + ''odont'', "tooth") are an extinct group of agnathan (jawless) vertebrates resembling eels, classified in the class Conodonta. For many years, they were known only from their tooth-like oral elements, which ... fauna, however, likely represent a change in the depositional environment of sedimentary sequences rather than a genuine biological extinction. Higher resolution δ13C isotope analysis identifies differences in the organic and carbonate carbon isotope curves (Δ13C), allowing the inference of a sustained drop in CO2 levels coincident with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ireviken Event
The Ireviken event was the first of three relatively minor extinction events (the Ireviken, Mulde event, Mulde, and Lau event, Lau events) during the Silurian period. It occurred at the Llandovery epoch, Llandovery/Wenlock epoch, Wenlock boundary (mid Silurian, ). The event is best recorded at Ireviken, Gotland, where over 50% of trilobite species became extinct; 80% of the global conodont species also became extinct in this interval. Anatomy of the event The event lasted around 200,000 years, spanning the base of the Wenlock epoch. It is associated with a period of global cooling. It comprises eight extinction "datum points"—the first four being regularly spaced, every 30,797 years, and linked to the Milankovic cycles, Milankovic obliquity cycle. The fifth and sixth probably reflect maxima in the precessional cycles, with periods of around 16.5 and 19 ka. The final two data are much further spaced, so harder to link with Milankovic cycle, Milankovic changes. Casualties The mec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Stack
A stack or sea stack is a geological landform consisting of a steep and often vertical column or columns of rock in the sea near a coast, formed by wave erosion. Stacks are formed over time by wind and water, processes of coastal geomorphology. britannica.com They are formed when part of a is by , which is the force of the sea or water crashing against the rock. The force of the water weakens cracks in the headland, causi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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