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Maastrichtian Extinctions
The Maastrichtian ( ) is, in the International Commission on Stratigraphy (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 . The Maastrichtian was preceded by the Campanian and succeeded by the Danian (part of the Paleogene and Paleocene). It is named after the city of Maastricht, the capital and largest city of the Limburg province in the Netherlands. The Cretaceous–Paleogene extinction event (formerly known as the Cretaceous–Tertiary extinction event) occurred at the end of this age. In this mass extinction, many commonly recognized groups such as non-avian dinosaurs, plesiosaurs and mosasaurs, as well as many other lesser-known groups, died out. The cause of the extinction is most commonly linked to an asteroid about wide colliding with Earth, ending the Cretaceous. Stratigraphic definitions Definition ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International Commission On Stratigraphy
The International Commission on Stratigraphy (ICS), sometimes unofficially referred to as the International Stratigraphic Commission, is a daughter or major subcommittee grade scientific organization that concerns itself with stratigraphy, stratigraphical, geology, geological, and chronology, geochronological matters, worldwide. It is the largest subordinate body of the International Union of Geological Sciences (IUGS). The ICS is essentially a permanent working committee, working subcommittee, which meets far more regularly than the quadrennial meetings scheduled by the IUGS, when it meets as a congress or committee, membership of the whole. Aims One of its main aims, a project begun in 1974, is to establish a multidisciplinary standard and global geologic time scale that will ease paleontology, paleontological and geobiology, geobiological comparisons region to region by benchmarks with stringent and rigorous strata criteria called Global Boundary Stratotype Section and Points ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
System (stratigraphy)
A system in stratigraphy is a sequence of strata (rock layers) that were laid down together within the same corresponding geological period. The associated period is a chronological time unit, a part of the geological time scale, while the system is a unit of chronostratigraphy. Systems are unrelated to lithostratigraphy, which subdivides rock layers on their lithology. Systems are subdivisions of erathems and are themselves divided into series and stages. Systems in the geological timescale The systems of the Phanerozoic were defined during the 19th century, beginning with the Cretaceous (by Belgian geologist Jean d'Omalius d'Halloy in the Paris Basin) and the Carboniferous (by British geologists William Conybeare and William Phillips in 1822). The Paleozoic and Mesozoic were divided into the currently used systems before the second half of the 19th century, except for a minor revision when the Ordovician system was added in 1879. The Cenozoic has seen more recent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction Event
An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by a sharp fall in the diversity and abundance of multicellular organisms. It occurs when the rate of extinction increases with respect to the background extinction rate and the rate of speciation. Estimates of the number of major mass extinctions in the last 540 million years range from as few as five to more than twenty. These differences stem from disagreement as to what constitutes a "major" extinction event, and the data chosen to measure past diversity. The "Big Five" mass extinctions In a landmark paper published in 1982, Jack Sepkoski and David M. Raup identified five particular geological intervals with excessive diversity loss. They were originally identified as outliers on a general trend of decreasing extinction rates during the Phanerozoic, but as more stringent statistical tests have been applied t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tertiary Period
The Tertiary ( ) is an obsolete Period (geology), geologic period spanning 66 million to 2.6 or 1.8 million years ago. The period began with the extinction of the non-bird, avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic, Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene, Pliocene Epoch. The Tertiary has not been recognised by the International Commission on Stratigraphy (ICS) since the late 1980s, with the timespan of the Tertiary now being split in to the earlier Paleogene and the more recent Neogene periods, though the Tertiary continues to be used in some scientific publications. Historical use of the term The term Tertiary was first used by Giovanni Arduino (geologist), Giovanni Arduino during the mid-18th century. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in Northern Italy. Later a fourth period, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Extinction Event
The Cretaceous–Paleogene (K–Pg) extinction event, also known as the K–T extinction, was the extinction event, mass extinction of three-quarters of the plant and animal species on Earth approximately 66 million years ago. The event caused the extinction of all non-avian dinosaurs. Most other tetrapods weighing more than also became extinct, with the exception of some ectothermic species such as sea turtles and crocodilians. It marked the end of the Cretaceous period, and with it the Mesozoic era, while heralding the beginning of the current era, the Cenozoic. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the Cretaceous–Paleogene boundary, K–Pg boundary or K–T boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows unusually high levels of the metal iridium, which is more common in asteroids than in the Earth's crust. As originally proposed in 1980 by a team of scientists le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Netherlands
, Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Netherlands. The Netherlands consists of Provinces of the Netherlands, twelve provinces; it borders Germany to the east and Belgium to the south, with a North Sea coastline to the north and west. It shares Maritime boundary, maritime borders with the United Kingdom, Germany, and Belgium. The official language is Dutch language, Dutch, with West Frisian language, West Frisian as a secondary official language in the province of Friesland. Dutch, English_language, English, and Papiamento are official in the Caribbean Netherlands, Caribbean territories. The people who are from the Netherlands is often referred to as Dutch people, Dutch Ethnicity, Ethnicity group, not to be confused by the language. ''Netherlands'' literally means "lower countries" i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limburg (Netherlands)
Limburg (; ), also known as Dutch Limburg, is the southernmost of the twelve provinces of the Netherlands. It is bordered by Gelderland to the north and by North Brabant to the west. Its long eastern boundary forms the border with the German state of North Rhine-Westphalia. To the west is the border with the Belgian province of Limburg, part of which is delineated by the river Meuse. To the south, Limburg is bordered by the Belgian province of Liège. The Vaalserberg is the extreme southeastern point, the tripoint of the Netherlands, Germany, and Belgium. Limburg had a population of about 1,128,000 in January 2023. Its main municipalities are the provincial capital Maastricht (population 120,837 as of January 2022), Venlo (population 102,176) in the northeast, as well as Sittard-Geleen (population 91,760, bordering both Belgium and Germany) and Heerlen (population 86,874) in the south. More than half of the population, approximately 650,000 people, live in the south of Limb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maastricht
Maastricht ( , , ; ; ; ) is a city and a Municipalities of the Netherlands, municipality in the southeastern Netherlands. It is the capital city, capital and largest city of the province of Limburg (Netherlands), Limburg. Maastricht is located on both sides of the Meuse (), at the point where the river is joined by the Jeker. Mount Saint Peter (''Sint-Pietersberg'') is largely situated within the city's municipal borders. Maastricht is adjacent to the border with Belgium and is part of the Meuse-Rhine Euroregion, an international metropolis with a population of about 3.9 million, which includes the nearby German and Belgian cities of Aachen, Liège, and Hasselt. Maastricht developed from a Roman Republic, Roman settlement (''Trajectum ad Mosam'') to a medieval river trade and religious centre. In the 16th century it became a garrison town and in the 19th century an early industrial centre. Today, the city is a thriving cultural and regional hub. It became well known through ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene
The Paleogene Period ( ; also spelled Palaeogene or Palæogene) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period Ma (million years ago) to the beginning of the Neogene Period Ma. It is the first period of the Cenozoic Era, the tenth period of the Phanerozoic and is divided into the Paleocene, Eocene, and Oligocene epochs. The earlier term Tertiary Period was used to define the time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognized as a formal stratigraphic term, "Tertiary" still sometimes remains in informal use. Paleogene is often abbreviated "Pg", although the United States Geological Survey uses the abbreviation "" for the Paleogene on the Survey's geologic maps. Much of the world's modern vertebrate diversity originated in a rapid surge of diversification in the early Paleogene, as survivors of the Cretaceous–Paleogene extinction event took advantage of empty ecolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Danian
The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretaceous–Paleogene extinction event . The age ended , being followed by the Selandian. Stratigraphic definitions The Danian was introduced in scientific literature by German-Swiss geologist Pierre Jean Édouard Desor in 1847 following a study of fossils found in France and Denmark.Danien Den Store Danske Encyklopædi He identified this stage in deposits from [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Campanian
The Campanian is the fifth of six ages of the Late Cretaceous epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campanian spans the time from 83.6 (± 0.2) to 72.1 (± 0.2) million years ago. It is preceded by the Santonian and it is followed by the Maastrichtian. The Campanian was an age when a worldwide sea level rise covered many coastal areas. The morphology of some of these areas has been preserved: it is an unconformity beneath a cover of marine sedimentary rocks. Etymology The Campanian was introduced in scientific literature by Henri Coquand in 1857. It is named after the French village of Champagne in the department of Charente-Maritime. The original type locality was a series of outcrops near the village of Aubeterre-sur-Dronne in the same region. Definition The base of the Campanian Stage is defined as a place in the stratigraphic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
