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29-626: The thickly wooded Weser ridge is one of the northern outliers of the German Central Uplands on the southern edge of the North German Plain and forms part of the TERRA.vita Nature Park in the west and Weser Uplands Schaumburg-Hameln Nature Park in the east. The Weser Hills are widely known because of Schaumburg Castle which stands on the Nesselberg (c. 225 m above NN ) in

58-563: A land mass, which has been named Gondwana (present day South America, Africa, Antarctica, Arabia , the Indian subcontinent , Zealandia and Australia), straddled the space between the South Pole and the Equator on one side of the globe. Off to the west were three other masses: Laurentia , Siberia and Baltica , located as if on the vertices of a triangle. To the south of them was a large archipelago,

87-632: A rare green mineral first discovered in the Vogtland district of Saxony in Germany, which is in the Variscan belt, has the same etymology.) Hercynian , on the other hand, derives from the Hercynian Forest . Both words were descriptive terms of strike directions observed by geologists in the field, variscan for southwest to northeast, hercynian for northwest to southeast. The variscan direction reflected

116-590: A similar shift in meaning. Today, Hercynian is often used as a synonym for Variscan but is somewhat less used than the latter in the English speaking world. In the United States, it is used only for European orogenies; the contemporaneous and genetically linked mountain-building phases in the Appalachian Mountains have different names. The regional term Variscan underwent a further meaning shift since

145-668: A wide belt north of the Algarve and extending into the northernmost part the autonomous region of Andalusia and southern Extremadura . In the Czech Republic and southwestern Poland the Bohemian Massif is the eastern end of the unmodified Variscan belt of crustal deformation in Europe. Further Variscan developments to the southeast are partly hidden and overprinted by the Alpine orogeny . In

174-644: Is one of the three major natural regions of Germany . It stretches east to west across the country. To the north lies the North German Plain or Northern Lowland ; to the south, the Alps and the Alpine Foreland . The German Central Uplands, like the Scandinavian and British mountain ranges and the Urals , belong to the oldest mountains of Europe, even if their present-day appearance has only developed relatively recently. In

203-574: Is the local intensity of exogenous processes. The table lists the ranges peaking over 300 m above sea level widely seen as part of the Central Uplands. The coordinates are of the respective peaks. Many of the uplands overlap. The ranges are listed by height. Download coordinates as: [REDACTED] Media related to Mittelgebirge at Wikimedia Commons [REDACTED] The dictionary definition of Mittelgebirge at Wiktionary Variscan orogeny The Variscan orogeny , or Hercynian orogeny ,

232-631: The Alps a Variscan core is built by Mercantour , Pelvoux , Belledonne , Montblanc and Aar Massif . Dinaric , Greek and Turkish mountain chains are the southeastern termination of the Variscan proper. The Variscan was contemporaneous with the Acadian and Alleghenian orogeny in the United States and Canada, responsible for forming the Ouachita and Appalachian Mountains . North American areas with Variscan foldbelts include New England , Nova Scotia and Newfoundland and Labrador . The Moroccan Meseta and

261-855: The Anti-Atlas in northwestern Africa show close relations to the Appalachian Mountains and used to form the eastern part of the Appalachian orogeny before the opening of the Atlantic Ocean in Jurassic times. 'Variscan' mountains in a broad chronological sense include the Urals , the Pamir , the Tian Shan and other Asian foldbelts. The Variscan orogeny involved a complicated heterogeneous assembly of different microplates and heterochronous collisions, making

290-558: The Carboniferous , i.e. about 350 million years ago, Variscan mountain ranges were formed in central Europe by the uplifting caused by tectonic plate collision. Immediately after their formation the erosion of the mountains began under the influence of exogenous processes during the Permian period. During the Triassic period, which began about 225 million years ago, what is now central Europe

319-779: The Harz ), or downfaulted (trough faults or graben such as the Upper Rhine Valley ) or thrust over one another (tilted fault blocks such as the Ore Mountains ). Thus the German Central Uplands exhibit the widest variety of forms, something that is also attributable to the erosion of sediments from the Mesozoic ( Triassic , Jurassic and Cretaceous ). In some ranges the sediments have been relatively well-preserved, in others they have been carried away completely. The determining factor

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348-523: The Rhine Massif (Ardennes, Eifel , Hunsrück , Taunus and other regions on both sides of Middle Rhine Valley), the Black Forest and Harz Mountains remain as testimony. In southern Iberia it is marked by a classic strike-slip suture zone between very distinct suspect terranes, and clear evidence can be seen of ductile shearing between high-grade metamorphic rocks and lower grade sedimentary rocks in

377-726: The terrane Avalonia , rifted off the north Gondwana margin in early Ordovician . By the end of the Silurian and in Early Devonian times, Baltica and Laurentia drifted towards each other, closing the Iapetus Ocean between them. They collided in the Caledonian orogeny and formed the Caledonide mountains of North America, Greenland , the British Isles and Norway . Seafloor spreading to

406-541: The 1960s. Geologists generally began to use it to characterize late Paleozoic fold-belts and orogenic phases having an age of approximately 380 to 280 Ma. Some publications use the term Variscan for fold belts of even younger age, deviating from the meaning as a term for the North American and European orogeny related to the Gondwana-Laurasia collision. The North American and European Variscan Belt includes

435-671: The British Isles, northern Germany, Scandinavia and western Russia). In late Devonian and in the Carboniferous the archipelago Armorica of southern Europe, which had rifted off Gondwana after Avalonia later in the Ordovician, was pushed into Avalonia, creating a second range, the North American/European Variscan, to the east of the Caledonide/Appalachian. The collision of Gondwana proper with Laurussia followed in

464-632: The Schaumburg district of the town of Rinteln , and is the emblem of Schaumburg Land . The Weser Hills cross the counties of Minden-Lübbecke , Schaumburg and Hameln-Pyrmont in a roughly east–west direction, from the town of Porta Westfalica and the Westphalian Gap in the west past Rinteln to Hessisch Oldendorf in the east, where they transition seamlessly to the Süntel , a ridge of similar height running from northwest to southeast. They form part of

493-596: The Weser Hills, and roughly parallel to them, flows the River Weser, from Hessisch-Oldendorf in the east, through Rinteln, towards Vlotho in the west, before turning northeast to the town of Porta Westfalica. These northern areas around the Upper Weser Valley , south of the hills are an old area of settlement, which was protected by Schaumburg Castle on the hill of Nesselberg . From the water gap at Porta Westfalica -

522-690: The Westphalian Gap - the river swings north in order to reach the southern part of the North German Plain. North of the hills are the upper reaches of the Aue (also called the Bückeburger Aue ) that run roughly east to west. The Wesergebirge is a chain of about two dozen hills that are arranged one after another in a ridge and which reach a height of 326.1 m above NN at the Möncheberg in

551-606: The beginning of the Cenozoic era, some 70 million years ago, the process of erosion of the Hercynian mountain ranges changed. During the Tertiary , alpidic mountain building took place, in the course of which strong forces deformed the stumps of the Hercynian mountains. As these rocks were already folded, further tension led to cracks and fractures, which in turn created fault blocks . These blocks were later uplifted (forming horsts such as

580-590: The direction of ancient fold belts cropping out throughout Germany and adjacent countries and the meaning shifted from direction to the fold belt proper. One of the pioneers in research on the Variscan fold belt was the German geologist Franz Kossmat , establishing a still valid division of the European Variscides in 1927. The other direction, Hercynian , for the direction of the Harz Mountains in Germany, saw

609-478: The early Carboniferous, when the Variscan belt was already in place and actively developing. By the end of the Carboniferous, Gondwana had united with Laurussia on its western end through northern South America and northwestern Africa. Siberia was approaching from the northeast, separated from Laurussia only by shallow waters. Collision with Siberia produced the Ural Mountains in the latest Paleozoic and completed

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638-966: The east. In its centre section, west of the A 2 motorway , they reach a maximum height of 278 m at the Wülpker Egge and a height of 235.2 m at the westernmost hill of the Weser chain, the Jakobsberg , which is located east of Porta Westfalica and on which the Jakobsberg transmission tower stands. The hills and elevations of the Wesergebirge, as seen from west to east, are given below together with their heights in metres above Normalnull (NN) : Bundesanstalt für Landeskunde und Raumforschung: Geographische Landesaufnahme 1:200000. Naturräumliche Gliederung Deutschlands. Die naturräumlichen Einheiten auf Blatt 85 Minden. Bad Godesberg 1959 Central Uplands The Central Uplands ( German : die Mittelgebirge )

667-463: The exact reconstruction of the plate tectonic processes difficult. Plate convergence that caused the Caledonian orogeny in the Silurian continued to form the Variscan orogeny in the succeeding Devonian and Carboniferous Periods. Both orogenies resulted in the assembly of a super-continent, Pangaea , which was essentially complete by the end of the Carboniferous. In the Ordovician Period,

696-896: The formation of Pangaea. Eastern Laurussia was still divided from Gondwana by the Paleotethys Ocean. In the Triassic Period of the Mesozoic Era, animals could move without oceanic impediment from Siberia over the North Pole to Antarctica over the South Pole. In the Mesozoic Era, rifting and subsequent opening of the Atlantic split Pangaea. As a consequence, the Variscan Belt around the then periphery of Baltica ended up many hundreds of miles from

725-867: The mountains of Portugal and Spain ( Galicia , and Pyrenees ), southwestern Ireland (i.e. Munster ), Cornwall , Devon , Pembrokeshire , the Gower Peninsula and the Vale of Glamorgan . Its effects are present in France from Brittany , below the Paris Basin to the Ardennes , the Massif Central , the Vosges and Corsica . The Variscan Belt reappears in Sardinia in Italy and in Germany where

754-682: The perimeter of the Weser Uplands and thus also the German Central Uplands which lie south of the North German Plain . North of the Weser Hills there are only a few hills of the Calenberg Uplands , such as the nearby ridges of Harrl and Bückeberge . To the west, on the other side of the Porta Westfalica, the chain continues as the Wiehen Hills , geologically of similar formation, reaching Bramsche (northwest of Osnabrück ). South of

783-566: The south of Avalonia pushed the latter into north Laurentia and thrust up the northern Appalachian Mountains in the acadian phase of the Caledonian orogeny. Contemporaneously the Tornquist Sea between Avalonia and Baltica was entirely closed. Thus Avalonia formed the southern coast of the new continent Euramerica ( Laurussia , the Old Red Sandstone continent in present-day North America,

812-423: Was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea . The name Variscan comes from the Medieval Latin name for the district Variscia , the home of a Germanic tribe, the Varisci ; Eduard Suess , professor of geology at the University of Vienna , coined the term in 1880. ( Variscite ,

841-421: Was sometimes above and sometimes below sea level. As a result, there are various layers of sedimentary rock in the Central Uplands: in most cases new red sandstone has been laid down as the terrestrial layer of rock and keuper and muschelkalk as marine sedimentary layers. The Jurassic period primarily saw the formation of limestone , whilst chalk was the main deposition from the Cretaceous period. With

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