Blade (geomorphology)

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Upper part of the Ochsenfurter Klinge, which emerges from the town's Klingentor into the Main Valley

Blades are by water and debris - erosion resulting small V-shaped valleys of larger and usually valleys valleys . They form short, narrow, but steep valleys without a valley floor . The further deepening due to erosion and receding erosion is essentially caused by the water from rivulets and streams and their gradients and can still be observed today. Erosion, sedimentation and transport are mutually dependent.

Surname

The term "blade" for small notch valleys is said to come from the noises made by the streams during high water. Another interpretation says that the valleys are as if struck by blades. In the whole of southwest Germany, also in the Swabian and Franconian Alb , small notch valleys are known as the Klinge, Tobel and Klammen .

This V-shaped valleys are also the habitat of the midwife toad , which is widely popular known as stone jack or clinker toad their spawning grounds were named accordingly bell Siepen, bell Born, Klingelschlade, Klingelpütt or bells pond because the mating calls of this Newt's are very characteristic.

In north-west Germany such erosion valleys are called Siepen , Siefen or Seif, or also Sieke.

geomorphology

Water and rubble erosion on the slope of a layer step

Blades are still exposed to erosion processes, especially in smaller catchment areas of heavily forested low mountain ranges, where springs easily emerge due to the alternating layers of permeable sand or limestone over dense clay and marl rocks . Slope undercutting often occurs, which can trigger small and medium-sized landslides or even mud flows ( mudflows ). In southwest Germany, these processes are particularly effective in the steep valleys flowing into the Rhine system.

In harder, fissured (and therefore water-permeable) rocks, landslides are less common. Instead, rock falls or even rock falls occur on rock massifs. These processes are significantly favored in the winter months by frost weathering. Steep rock faces in the Muschelkalk and Weißjura are particularly vulnerable .

Occurrence

Karst spring of the Loue , French Jura , near Orhans / Pontarlier

In the area of ​​the Swabian and Franconian Alb, blades are less common than in the upstream mountains of the south-west German layer level country.

At the layer boundaries of steep Jura walls - such as those of the Albtraufs or the Swiss-French Jura - strong karst springs that pour out continuously or periodically have cleared out particularly steep, often concave vertical rock niches, e.g. B. the Devil's Blade near Heubach (Albtrauf der Ostalb) and the Résurgence in the French Jura ( Loue source ).

Individual evidence

  1. Georg Wagner: Introduction to the history of the earth and landscape with special consideration of southern Germany. Hohenlohesche Buchhandlung Ferdinand Rau, Öhringen 1960, p. 81.
  2. Joachim Eberle u. a .: Germany's south - from the Middle Ages to the present. Spektrum-Akademischer Verlag, Heidelberg 2007, ISBN 978-3-8274-1506-6 , p. 176.

literature

  • Joachim Eberle u. a .: Germany's south - from the Middle Ages to the present. Spektrum-Akademischer Verlag, Heidelberg 2007, ISBN 978-3-8274-1506-6 .
  • Georg Wagner: Introduction to the history of the earth and landscape with a special focus on southern Germany. Hohenlohesche Buchhandlung Ferdinand Rau, Öhringen 1960.