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| Geology of the Alps |
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| Tectonic subdivision |
| Formation & rocks |
| Geological structures |
| Paleogeographic terminology |
 Geologyportal |
The Aarmassif or Aaremassif (German: Aarmassiv) is a geologic massif in the Swiss Alps. It contains a number of large mountain chains and parts of mountain chains.
The massif is named after the Aar, a river that has its source in the Aarmassif.
The Aarmassif crops out in the eastern part of the Bernese Alps and the Lepontine Alps, roughly form Leukerbad in the west to the Tödi in the east. Further east the massif only appears in small windows like the Vättner window between Gigerwald and Vättis in Sankt Gallen and at the Limmerensee in the same canton.
The Aarmassif is part of the Helvetic zone of the Alps, which consists of material originally from the European tectonic plate. The Aarmassif has lithologies common for Paleozoic basement rocks all over Europe, deformed and metamorphosed during the Variscan orogeny. Younger Mesozoic sedimentary rocks were eroded from this basement as a thrust fault brought the basement to the surface in the Alpine orogeny. Other places, where the European basement crops out in the Helvetic zone, are the mountain chains of the Massif des Écrins and of Mont Blanc in the French and Italian Alps.
The lithologies of the basement rocks are mainly gneisses, schists and amphibolites. These were in some places intruded by Permian granites after the Variscan orogeny, called Aare granite. During a late phase in the Alpine orogeny in the Tertiary the Aarmassif was uplifted in the form of a large elongated dome structure. The overlying limestones of the Helvetic nappes now have a very high dip angle, forming a ridge that appears at the Eiger and south of the Jungfrau mountain.
The Alps form part of a Cenozoic orogenic belt of mountain chains, called the Alpide belt, that stretches through southern Europe and Asia from the Atlantic all the way to the Himalayas. This belt of mountain chains was formed during the Alpine orogeny. A gap in these mountain chains in central Europe separates the Alps from the Carpathians to the east. Orogeny took place continuously and tectonic subsidence has produced the gaps in between.
The Finsteraarhorn is a mountain lying on the border between the cantons of Bern and Valais. It is the highest mountain of the Bernese Alps and the most prominent peak of Switzerland. The Finsteraarhorn is the ninth-highest mountain and third-most prominent peak in the Alps. In 2001 the whole massif and surrounding glaciers were designated as part of the Jungfrau-Aletsch World Heritage Site.
The Variscan or Hercynianorogeny was a geologic mountain-building event caused by Late Paleozoic continental collision between Euramerica (Laurussia) and Gondwana to form the supercontinent of Pangaea.
The Helvetic zone, Helvetic system or the Helveticum is a geologic subdivision of the Alps. The Helvetic zone crops out mainly in Switzerland, hence the name. Rocks in the Helvetic zone are sedimentary and were originally deposited at the southern margin of the European plate. The Helvetic zone correlates with the French Dauphinois zone, French geologists often prefer the French name but normally this is considered the same thing.
The Penninic nappes or the Penninicum, commonly abbreviated as Penninic, are one of three nappe stacks and geological zones in which the Alps can be divided. In the western Alps the Penninic nappes are more obviously present than in the eastern Alps, where they crop out as a narrow band. The name Penninic is derived from the Pennine Alps, an area in which rocks from the Penninic nappes are abundant.
The Austroalpine nappes are a geological nappe stack in the European Alps. The Alps contain three such stacks, of which the Austroalpine nappes are structurally on top of the other two. The name Austroalpine means Southern Alpine, because these nappes crop out mainly in the Eastern Alps.
The greywacke zone is a band of Paleozoic metamorphosed sedimentary rocks that forms an east-west band through the Austrian Alps.
The Helvetic nappes are a series of nappes in the Northern part of the Alps and part of the Helvetic zone. They consist of Mesozoic limestones, shales and marls that were originally deposited on the southern continental margin of the European continent. During the Alpine orogeny they were thrust north over a décollement and at the same time were internally deformed by folding and thrusting.
The Saxothuringian Zone, Saxo-Thuringian zone or Saxothuringicum is in geology a structural or tectonic zone in the Hercynian or Variscan orogen of central and western Europe. Because rocks of Hercynian age are in most places covered by younger strata, the zone is not everywhere visible at the surface. Places where it crops out are the northern Bohemian Massif, the Spessart, the Odenwald, the northern parts of the Black Forest and Vosges and the southern part of the Taunus. West of the Vosges terranes on both sides of the English Channel are also seen as part of the zone, for example the Lizard complex in Cornwall or the Léon Zone of the Armorican Massif (Brittany).
The Bohemian Massif is a geomorphological province in Central Europe. It is a large massif stretching over most of the Czech Republic, eastern Germany, southern Poland and northern Austria.
The Moldanubian Zone is in the regional geology of Europe a tectonic zone formed during the Variscan or Hercynian Orogeny. The Moldanubian Zone crops out in the Bohemian Massif and the southern part of the Black Forest and Vosges and contains the highest grade metamorphic rocks of Variscan age in Europe.
The Western Carpathians are an arc-shaped mountain range, the northern branch of the Alpine-Himalayan fold and thrust system called the Alpide belt, which evolved during the Alpine orogeny. In particular, their pre-Cenozoic evolution is very similar to that of the Eastern Alps, and they constitute a transition between the Eastern Alps and the Eastern Carpathians.
An external massif is, in the geology of the Alps, a place where crystalline rocks of the European plate crop out. Such massifs are found north and west of the Penninic zone as tectonic windows in the Helvetic Zone. They differ from the crystalline nappes in that they were originally part of the European plate, while the Penninic nappes were part of the crust below various domains in the Tethys Ocean.
The Gotthard nappe is, in the geology of the Alps a nappe in the Helvetic zone of Switzerland. It consists of crystalline rocks that were, before the formation of the Alps, part of the upper crust of the southern margin of the European continent. As it names suggests, the Gotthard nappe lies in close proximity to the Gotthard Massif.
The Pyrenees are a 430-kilometre-long, roughly east–west striking, intracontinental mountain chain that divide France, Spain, and Andorra. The belt has an extended, polycyclic geological evolution dating back to the Precambrian. The chain's present configuration is due to the collision between the microcontinent Iberia and the southwestern promontory of the European Plate. The two continents were approaching each other since the onset of the Upper Cretaceous (Albian/Cenomanian) about 100 million years ago and were consequently colliding during the Paleogene (Eocene/Oligocene) 55 to 25 million years ago. After its uplift, the chain experienced intense erosion and isostatic readjustments. A cross-section through the chain shows an asymmetric flower-like structure with steeper dips on the French side. The Pyrenees are not solely the result of compressional forces, but also show an important sinistral shearing.
The regional geology of France is commonly divided into the Paris Basin, the Armorican Massif, the Massif Central, the Aquitaine Basin, the Pyrenees, the Alps, the Côte languedocienne, the Sillon rhodanien, the Massif des Vosges, the Massif Ardennais, the Alsace graben and Flanders Basin.
The geology of Germany is heavily influenced by several phases of orogeny in the Paleozoic and the Cenozoic, by sedimentation in shelf seas and epicontinental seas and on plains in the Permian and Mesozoic as well as by the Quaternary glaciations.
The geology of Austria consists of Precambrian rocks and minerals together with younger marine sedimentary rocks uplifted by the Alpine orogeny.
The geology of Croatia has some Precambrian rocks mostly covered by younger sedimentary rocks and deformed or superimposed by tectonic activity.
The geology of the Czech Republic is very tectonically complex, split between the Western Carpathian Mountains and the Bohemian Massif.
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