Fold Mountains

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Very simplified representation of the collision of the continental blocks of two different tectonic plates with fold mountains above the collision zone.
Large-scale S-shaped folding in the Swiss Alps ( Gasterntal )

Fold mountains are mountains that arise when at least two tectonic plates of the earth's crust move towards one another and exert pressure on one another , which leads to the crust being deformed and pushed up ("unfolded") in the contact zone of the two plates (→  mountain formation ).

This creates a single mountain range or even a whole series of approximately parallel mountain ranges, which is why one speaks of chain mountains . These mountain ranges are not infrequently curved in the map.

Fold mountains , the most common are high mountain form on Earth. In contrast, Bruchschollengebirge only reach low mountain ranges. Many European low mountain ranges are rupture clod mountains, in which the clods rise or fall as a whole along the fracture zones without folding . However, the rocks of these rupture clods may have already undergone fold formation in the geological past and are therefore still folded. This is e.g. B. in the Harz or the Rhenish Slate Mountains the case. Bruchschollengebirge often do not form a long mountain range, but rather have a rounded or oval shape on the map.

In addition to the earth, fold mountains can also arise on other planets , provided that plate tectonics are possible there . The prerequisite for this is a minimum size of the celestial body (depending on its composition several thousand kilometers in diameter), a solid crust over a deformable mantle or core and probably also liquid water. So far, the earth is the only planet of which plate tectonics is known. Because of its early cooling, the Earth's moon was unable to develop mountains of folds. The outskirts of some mare were created by the impact of large asteroids.

Significant fold mountains

Distribution of the geologically young fold mountains (the so-called Alpidic chains ) in Europe and Asia

Africa

Asia

New Zealand

Europe

North America

South America

literature

  • Hermann Wagner: Textbook of geography. Second part, 1st edition, Salzwasser Verlag GmbH, reprint of the original from 1921, ISBN 978-3-84603-983-0 .
  • Frank Ahnert: Introduction to Geomorphology. 4th edition, Verlag Eugen Ulmer, Stuttgart 2009, ISBN 978-3-8252-8103-8 .

See also

Web links