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Buntsandstein
The Buntsandstein (German for ''coloured'' or ''colourful sandstone'') or Bunter sandstone is a lithostratigraphy, lithostratigraphic and allostratigraphy, allostratigraphic unit (a sequence of rock strata) in the Subsurface (geology), subsurface of large parts of west and central Europe. The Buntsandstein predominantly consists of sandstone layers of the Lower Triassic series (stratigraphy), series and is one of three characteristic Triassic units, together with the Muschelkalk and Keuper that form the Germanic Trias Supergroup (geology), Supergroup. The Buntsandstein is similar in age, sedimentary facies, facies and lithology with the Bunter (geology), Bunter of the British Isles. It is normally lying on top of the Permian Zechstein and below the Muschelkalk. In the past the name Buntsandstein was in Europe also used in a chronostratigraphy, chronostratigraphic sense, as a subdivision of the Triassic system. Among reasons to abandon this use was the discovery that its base lies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bunter (geology)
Bunter Pebble Beds is the name formerly given to a set of sandstone deposits within the New Red Sandstone containing rounded pebbles. They are thought to be alluvial deposits and, judging from the rounding of the mainly quartzite pebbles, to have resulted from prolonged transportation in a large and turbulent river, resulting in powerful abrasion. Etymology The name "Bunter" derives from the German term "Buntsandstein", "bunt" meaning "variegated" or "colourful", referring to the colour of the sandstone deposit, which varies from reddish to greenish. Utility The pebbles, also called cobbles, which can be used as gravel, as ballast or as cobblestones, are mainly milky-white quartzite but can vary in colour and composition, including some that are hard, reddish-coloured sandstone. The sandstone in which these pebbles are deposited can be used for building or as an aggregate for cement or concrete. The sandstone can be hard enough for building, yet easy enough to "work", r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithostratigraphy
Lithostratigraphy is a sub-discipline of stratigraphy, the geological science associated with the study of strata or rock layers. Major focuses include geochronology, comparative geology, and petrology. In general, strata are primarily igneous or sedimentary relating to how the rock was formed. Sedimentary layers are laid down by deposition of sediment associated with weathering processes, decaying organic matter (biogenic) or through chemical precipitation. These layers are often distinguishable as having many fossils and are important for the study of biostratigraphy. Igneous layers occur as stacks of lava flows, layers of lava fragments (called tephra) both erupted onto the Earth's surface by volcanoes, and in layered intrusions formed deep underground. Igneous layers are generally devoid of fossils and represent magmatic or volcanic activity that occurred during the geologic history of an area. There are a number of principles that are used to explain relationships betwe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chronostratigraphy
Chronostratigraphy is the branch of stratigraphy that studies the ages of rock strata in relation to time. The ultimate aim of chronostratigraphy is to arrange the sequence of deposition and the time of deposition of all rocks within a geological region, and eventually, the entire geologic record of the Earth. The standard stratigraphic nomenclature is a chronostratigraphic system based on palaeontological intervals of time defined by recognised fossil assemblages ( biostratigraphy). The aim of chronostratigraphy is to give a meaningful age date to these fossil assemblage intervals and interfaces. Methodology Chronostratigraphy relies heavily upon isotope geology and geochronology to derive hard dating of known and well defined rock units which contain the specific fossil assemblages defined by the stratigraphic system. In practice, as it is very difficult to isotopically date most fossils and sedimentary rocks directly, inferences must be made in order to arrive at an age ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alluvial Fan
An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to Semi-arid climate, semiarid climates, but are also found in more humid environments subject to intense rainfall and in areas of modern glaciation. They range in area from less than to almost . Alluvial fans typically form where a flow of sediment or rocks emerge from a confined channel and are suddenly free to spread out in many directions. For example, many alluvial fans form when steep mountain valleys meet a flat plain. The transition from a narrow channel to a wide open area reduces the carrying capacity of flow and results in Deposition (geology), deposition of sediments. The flow can take the form of infrequent debris flows like in a landslide, or can be carried by an intermittent stream or creek. The reduction of flow is key to the formation of alluvial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clastic Rock
Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus,Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-3 chunks, and smaller grains of rock broken off other rocks by physical weathering.Essentials of Geology, 3rd Ed, Stephen Marshak, p. G-5 Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport, whether in suspension or as bed load, and in sediment deposits. Sedimentary clastic rocks Clastic sedimentary rocks are rocks composed predominantly of broken pieces or ''clasts'' of older weathered and eroded rocks. Clastic sediments or sedimentary rocks are classified based on grain size, clast and cementing material (matrix) composition, and texture. The classification factors are often useful in determining a sample's environment of deposition. An example of clastic environment would be a river system in which the full range of grains being transported b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleo-Tethys Ocean
The Paleo-Tethys or Palaeo-Tethys Ocean was an ocean located along the northern margin of the paleocontinent Gondwana that started to open during the Middle Cambrian, grew throughout the Paleozoic, and finally closed during the Late Triassic; existing for about 400 million years. Paleo-Tethys was a precursor to the Tethys Ocean (also called the Neo-Tethys), which was located between Gondwana and the Hunic terranes (continental fragments that broke off Gondwana and moved north). It opened as the Proto-Tethys Ocean subducted under these terranes and closed as the Cimmerian terranes (that also broke-off Gondwana and moved north) gave way to the Tethys Ocean. Confusingly, the Neo-Tethys is sometimes defined as the ocean south of a hypothesized mid-ocean ridge separating Greater India from Asia, in which case the ocean between Cimmeria and this hypothesized ridge is called the Meso-Tethys, i.e., the "Middle-Tethys". The so-called Hunic terranes are divided into the ''European H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evaporite
An evaporite () is a water- soluble sedimentary mineral deposit that results from concentration and crystallization by evaporation from an aqueous solution. There are two types of evaporite deposits: marine, which can also be described as ocean deposits, and non-marine, which are found in standing bodies of water such as lakes. Evaporites are considered sedimentary rocks and are formed by chemical sediments. Formation Although all water bodies on the surface and in aquifers contain dissolved salts, the water must evaporate into the atmosphere for the minerals to precipitate. For this to happen, the water body must enter a restricted environment where water input into this environment remains below the net rate of evaporation. This is usually an arid environment with a small drainage basin fed by a limited input of water. When evaporation occurs, the remaining water is enriched in salts, and they precipitate after the water becomes saturated. Depositional environments ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arid Climate
The desert climate or arid climate (in the Köppen climate classification ''BWh'' and ''BWk'') is a dry climate sub-type in which there is a severe excess of evaporation over precipitation. The typically bald, rocky, or sandy surfaces in desert climates are dry and hold little moisture, quickly evaporating the already little rainfall they receive. Covering 14.2% of Earth's land area, hot deserts are the second-most common type of climate on Earth after the Polar climate. There are two variations of a desert climate according to the Köppen climate classification: a hot desert climate (''BWh''), and a cold desert climate (''BWk''). To delineate "hot desert climates" from "cold desert climates", a mean annual temperature of is used as an isotherm so that a location with a ''BW'' type climate with the appropriate temperature above this isotherm is classified as "hot arid subtype" (''BWh''), and a location with the appropriate temperature below the isotherm is classified as "cold a ... [...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] |
Baltic Sea
The Baltic Sea is an arm of the Atlantic Ocean that is enclosed by the countries of Denmark, Estonia, Finland, Germany, Latvia, Lithuania, Poland, Russia, Sweden, and the North European Plain, North and Central European Plain regions. It is the world's largest brackish water basin. The sea stretches from 53°N to 66°N latitude and from 10°E to 30°E longitude. It is a Continental shelf#Shelf seas, shelf sea and marginal sea of the Atlantic with limited water exchange between the two, making it an inland sea. The Baltic Sea drains through the Danish straits into the Kattegat by way of the Øresund, Great Belt and Little Belt. It includes the Gulf of Bothnia (divided into the Bothnian Bay and the Bothnian Sea), the Gulf of Finland, the Gulf of Riga and the Bay of Gdańsk. The "Baltic Proper" is bordered on its northern edge, at latitude 60°N, by Åland and the Gulf of Bothnia, on its northeastern edge by the Gulf of Finland, on its eastern edge by the Gulf of Riga, and in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Sea
The North Sea lies between Great Britain, Denmark, Norway, Germany, the Netherlands, Belgium, and France. A sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian Sea in the north. It is more than long and wide, covering . It hosts key north European shipping lanes and is a major fishery. The coast is a popular destination for recreation and tourism in bordering countries, and a rich source of energy resources, including wind energy, wind and wave power. The North Sea has featured prominently in geopolitical and military affairs, particularly in Northern Europe, from the Middle Ages to the modern era. It was also important globally through the power northern Europeans projected worldwide during much of the Middle Ages and into the modern era. The North Sea was the centre of the Viking Age, Vikings' rise. The Hanseatic League, the Dutch Golden Age, Dutch Republic, and Kingdom of Great Britain, Brita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denmark
Denmark is a Nordic countries, Nordic country in Northern Europe. It is the metropole and most populous constituent of the Kingdom of Denmark,, . also known as the Danish Realm, a constitutionally unitary state that includes the Autonomous administrative division, autonomous territories of the Faroe Islands and Greenland in the north Atlantic Ocean.* * * Metropolitan Denmark, also called "continental Denmark" or "Denmark proper", consists of the northern Jutland peninsula and an archipelago of 406 islands. It is the southernmost of the Scandinavian countries, lying southwest of Sweden, south of Norway, and north of Germany, with which it shares a short border. Denmark proper is situated between the North Sea to the west and the Baltic Sea to the east.The island of Bornholm is offset to the east of the rest of the country, in the Baltic Sea. The Kingdom of Denmark, including the Faroe Islands and Greenland, has roughly List of islands of Denmark, 1,400 islands greater than in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
