Granite and gneiss plateau

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Physical map of Austria, north of the Danube, the gneiss and granite highlands bordered in green

The gneiss and granite plateau , also granite and gneiss highlands , is one of the five major landscapes in Austria . In Upper and Lower Austria it forms the Mühlviertel and the Waldviertel .

Geologically it is Austria's share of the Bohemian mass .

Location and landscape

Typical landscape of the central Mühlviertel
Central area of ​​the Waldviertel

Austria comprises three basic natural areas : the Austrian Alps , the foothills and rim-alpine basins and the gneiss and granite highlands .

The granite and gneiss highlands are the northernmost and smallest of these three large landscapes, comprise around 10% of the Austrian national territory and are mainly located north of the Danube in the federal states of Lower Austria (Weinviertel, Waldviertel) and Upper Austria (Mühlviertel). In the south it borders on the Austrian Alpine Foreland (small parts are located south of the Danube), in the east on the Tullnerfeld and the Weinviertel . In the north, the Austrian- Czech state border is the end of the region. On the Czech side, the mountain ranges of the Bohemian-Moravian Highlands (Vysočina) , the Gratzener Uplands (Novohradské hory) - whose border zone with Austria is called Freiwald - and the Bohemian Forest (Šumava) join. In the west, Bavaria borders with the Bavarian Forest and the Neuburg Forest .

The gneiss and granite plateau is a low mountain range , which consists of a partly wavy and domed high plateau, staggered at the edges, partly strongly furrowed, with average heights of around 750 m. The landscape is called the hull landscape , an old mountain range that has been heavily overprinted over long geological periods and forms the Bohemian massif.

structure

The north-west is characterized by the foothills of the Bohemian Forest , with the high Bohemian Forest as the central chain, the south is the Mühlviertel highlands . The approximately 25 km wide Feldai valley between the Sternstein ( 1122  m above sea level ) and the Viehberg ( 1112  m above sea level ) separates the Bohemian Forest and the Freiwald from each other and is around 675  m above sea level. A. (near Summerau ) the lowest transition from the Danube region to the Vltava region in the Mühlviertel. The Mühlviertel and Waldviertel are separated by the Freiwald (Gratzener Bergland) and the Weinsberger Wald - this zone, with Ostrong and Jauerling , is called the Hohes Waldviertel . The east (the Waldviertel) rises steeply from the Danube and slopes down towards the north, only to merge back into the Bohemian-Moravian Highlands .

The peaks seldom exceed the Kolline height level, the highest point is the Plöckenstein at 1379  m above sea level. A. , who belongs in the chain of the high Bohemian Forest . Other high peaks are the striking Sternstein ( 1122  m above sea level ) and the Viehberg ( 1112  m above sea level ) in the Mühlviertel, as well as Tischberg ( 1063  m above sea level ), Weinsberg ( 1041  m above sea level ) and Ostrong ( 1061  m above sea level ) in the Waldviertel. The eastern edge is the Manhartsberg ( 537  m above sea level ).

Embedded in these high areas are the central areas of the granite and gneiss plateau: In the Mühlviertel, the Central Mühlviertel highlands with the Freistädter Basin , the southern Bohemian Forest foothills with the Mühltal , the southern Mühlviertel outskirts ( Klamer Basin , Gallneukirchner Basin ) and the Leonfeldner Hochland , the Aist- Naarn-Kuppenland and the Freiwald and Weinsberger Forest .
The eastern lower Waldviertel is formed by the Zwettler Land with the Ottenschlager Hochland , the Kamp-Kremser Hochland , and the Gföhler Plateau . At the northern border there is still the Gmünd depression , which forms the southern part of the Wittingau basin (Třeboňská) , which extends into the Czech Republic , the Litschauer Ländchen and - separated by Wieningerberg (Predigtstuhl) and the Wild - the Thaya highlands and the upper Thaya valley . The extensive Horner Basin lies on the border with the Weinviertel .

The gneiss and granite highlands also include the rock masses cut off from the Danube and their breakthrough valleys : The Sauwald ( 895  m above sea level ) between Eferding and Passau with the Danube valley, which is not named by name, via the Schlögener Schlinge to Aschach , the Kürnberger Forest ( Linzer breakthrough) near Linz, the Kristallinsporn von Wallsee , the Neustadtler Platte and the Strudengau (Greiner breakthrough) , the Hiesberg south of the Nibelungengau (which is considered a peripheral bay), as well as the Dunkelsteinerwald ( 725  m above sea level ) and the Wachau

Vegetation and climate

Blockheide-Gmünd Nature Park : Wool sack weathering in granite

In the wide hollows and valleys, agriculture dominates the picture, on the plateaus and ridges there is a mixed forest of spruce, fir and beech (subhercyan type), but forestry substitute spruce crops in large areas. In the low-lying areas, various mixed beech forest shapes dominate , there are also pedunculate oak and hornbeam forests and, to the east, red pine and oak forests . Bog formation is common, in the Waldviertel high and are Anmoore landscape forming. There is increasing heathland there .

The climate is rough and cool, Atlantic of the boreal type, in the wetter west also called Central European transitional climate , in the drier east area (Weinviertel) increasingly polar-subpolar and continental - Pannonian influenced. The climatic levels are 100 to 250 m lower than in the peripheral Alps , and the annual mean is up to 1 ° C lower. On the other hand, the climate is more even than in the northern Alps, and at altitudes around 900–1000 m arable farming is still possible (in the pre-Alps only grassland farming ). Fog is frequent, but the amount of precipitation at 700–1100 mm is comparatively low, and towards the east the amount of rain falls by roughly 200 mm, and the constant winds - predominantly from the northwest to the north - increase. Within the zone, however, there is an extreme climatic case: the outer northwest with 1500 mm is one of the rainy zones in Austria, the northeast with 560 mm (Horner Mulde) is one of the driest; near Zwettl is a cold pole of Austria (annual mean 6-7 ° C; -36.6 ° C, February 1929), and just 50 km away is the Wachau as a world-famous wine-growing region (9 ° C mean). The soils belong primarily to the brown earth - Podsol series and are rarely fertile as weathered gravel, only in the east there is also heavy soil, on the flank to the Weinviertel tertiary beach terraces with periglacial loess covers .

geology

Approximate location of the granite and gneiss plateau in the Bohemian Massif
Central European variscides
Structure and outcrop of the Central European Variscides. The granite and gneiss plateau (marked in red) lies in the south of the Bohemian Massif.

The granite and gneiss plateau is named after its structure of granite and gneiss , a rock association that is characteristic of large parts of the entire Bohemian mass (see →  crystalline complex ). In the center of the granite and gneiss plateau, the granite of the South Bohemian Pluton (stony soils) predominates and in the west and east the gneiss with deep soils predominate. Granite and gneiss units each strike approximately north-south. A special feature of the Colorful Series , a narrow range of rocks in the eastern gneiss region, is various other metamorphic rocks such as marble , calcium silicate slate , quartzite and graphite (slate), and Kriechbaum has a Cretaceous and ancient Tertiary originated from the granite through tropical weathering obtained kaolin occurrence. These rocks and minerals were and are being mined and used in large numbers ( Herschenberger granite , Neuhauser granite, Aalfanger granite, Hartberger granite, Schremser granite fine grain, Gebhartser syenite, Wachau marble ). Naturally exposed granite often shows wool sack weathering , and the typical weathering and erosion forms of the region include rocky seas , rocking stones and rocky pulpits .

The Bohemian Massif is a geologically ancient area of ​​Central Europe, a hull of the Variscan Mountains , which is broken up into clods by various fractures. The main part of the granite and gneiss plateau is formed by the Moldanubic , an early phase around 350–400 million years ago. It pushed over the Moravikum , the eastern mass, along an S-shaped line Schönberg am Kamp - Geras - Frain (Vranov). It is characterized by a lower degree of metamorphosis and a higher proportion of pre-Variscan granite gneisses ( Cadomian orogeny 650–545  mya ). The oldest known relic, however, is the Dobra gneiss , dated to 1377 mya.

The Bohemian Massif was an "abutment" for the formation of the Alps ; it extends under the molasse of the Alpine foothills to far below the edge of the Alps.

See also: Geological history of Lower Austria

Hydrology

The area drains almost completely - the southern flank with deep, sometimes gorge-like , meandering valleys directly - to the Danube and thus into the Black Sea . In the north, small portions drain over the Vltava to the Elbe and thus into the North Sea . Consequently, the main European watershed runs through the granite and gneiss plateau.

The most important rivers are from west to east (downstream of the Danube):

To the North Sea:

All these rivers are characterized by their reddish-brown, iron-rich and lime-free water, of - in the area of ​​the granite and gneiss lands - excellent water quality in the limnological sense.

literature

  • W. Kilian, F. Müller, F. Starlinger: The forest growth areas of Austria. A natural area structure according to forest ecological aspects . Ed .: Federal Forest Research Institute . 1993, ISSN  0374-9037 , main growth area 9: Mühl- and Waldviertel, p. 83 ff . ( online ( memento of October 31, 2013 in the web archive archive.today )).
  • Max H. Fink, Otto Moog, Reinhard Wimmer: Natural areas of flowing water in Austria . Ed .: Federal Environment Agency (=  monographs . Volume 128 ). Vienna 2000, ISBN 3-85457-558-0 , River Natural Areas 5: Granite and Gneiss highlands, p. 83 ff . ( [1] ).

Web links

Commons : Granite and Gneiss Plateau  - Collection of images, videos and audio files

Individual evidence

  1. ^ Community initiative LEADER + programming document Austria. Structural Funds 2000-2006. Federal Ministry of Agriculture, Forestry, Environment and Water Management. Approved March 26, 2001 K (2001) 820 ( PDF; 1.1 MB ( Memento from February 4, 2012 in the Internet Archive ))
  2. ↑ a b c Chapter 6.1: The large landscapes. In: MH Fink, O. Moog, R. Wimmer: Flowing waters - natural areas of Austria. Federal Environment Agency monographs. Vol. 128, Vienna 2000 ( PDF 470 kB), p. 26ff.
  3. ^ W. Kilian, F. Müller, F. Starlinger: The forestry growth areas of Austria. 1993, p. 29.
  4. ↑ Proseminar Applied Geoinformation (Ed.): Area Description Zwettl. ( Memento of July 29, 2007 in the Internet Archive ) 2004.
  5. ↑ Reinhard Müller; Archive for the history of sociology in Austria (ed.): Large Chronicle of Gramatneusiedl, Marienthal and Neu-Reisenberg 1928 to 1929. ( Memento from May 27, 2007 in the web archive archive.today )
  6. ↑ Map 40 January / July isotherms. In: Konzenn-Atlas. Ed. Hölzel, Vienna, 101st edition. 1975.
  7. ^ Gerhard Fuchs: The Moldanubian Gneiss Mountains. P. 121–128 in: R. Oberhauser (Red.): The Geological Structure of Austria. Springer-Verlag, Vienna 1980, ISBN 978-3-7091-3745-1 , p. 122
  8. ↑ Bernhard Gruber: Remarks on the geology and morphology of the Perg district, as well as on its deposits and usable rocks. Upper Austrian geo news. Jhrg. 10, 1995, pp. 3–9 ( PDF 640 kB)
  9. ↑ Natural stones in Austria , Association of Austrian Natural Stone Works, naturstein.at