Elevation crater
The elevation crater theory started in the 18th and 19th centuries and was an attempt to explain the origin of mountains and orogens. The theory held that mountains formed by vertical movements associated with volcanism.[1]
The idea held that magma and volcanic activity formed mountains was expressed as early as 1777 by Peter Simon Pallas who claimed the Urals and Altai Mountains formed this way. Pallas based his ideas on an granitic central axis he observed in these mountains.[2] The theory was revived and elaborated further by Leopold von Buch in the 19th century.[1] Observations supporting this view were also given by Alexander von Humboldt in his book Kosmos.[2]
Humbold and Buch considered basaltic volcanism to be linked to elevation craters while trachyte was the product of "true volcanoes".[3] Hermann Abich applied the theory to the Caucasus Mountains and following the views of Buch and Humboldt he linked mountain building to volcanism, leading him to take interest in the volcanoes of the Caucasus in the area.[3][4]
Swiss geologist Bernhard Studer refined the idea further. Working in the Alps, Studer considered the mountains to be roughly symmetrical with a Mittelzone containing the igneous rocks he believed had uplifted the Alps. These rocks were grouped in twelve Centralmassen. To the north and south of the Mittelzone there were two equivalent marginal zones: Nörliche Nebenzone and Südliche Nebenzone.[2] The theory, as posited by Studer, was popular among geologists in Switzerland and neighboring areas until the 1870s.[5]
References
- ^ a b Şengör (1982), p. 4
- ^ a b c Şengör (1982), p. 5
- ^ a b Seibold, Ilse; Seibold, Eugen (2006). "Hermann Wilhelm Abich im Kaukasus: Zum zweihundertsten Geburtstag". International Journal of Earth Sciences (in German). 95 (6): 1087–1100. doi:10.1007/s00531-006-0100-z.
- ^ Milanovsky, E.E. (2007). "Hermann Abich (1806 –1886): 'the Father of Caucasian Geology and his travels in the Caucasus and Armenian Highlands". In Jackson, Patrick N. Wyse (ed.). Four Centuries of Geological Travel: The Search for Knowledge on Foot, Bicycle, Sledge and Camel. Geological Society Special Publication. pp. 177–181.
- ^ Şengör (1982), p. 6
Bibliography
- Şengör, Celâl (1982). "Classical theories of orogenesis". In Miyashiro, Akiho; Aki, Keiiti; Şengör, Celâl (eds.). Orogeny. John Wiley & Sons. ISBN 0-471-103764.