Glacier pot
Glacier pots or giant pots ( Jättegryta in Swedish ) are pot-like or shaft- like depressions in rock ( ponds ) that are created by flowing water in the area of glacial ice.
Emergence
Glacier pots are formed by meltwater that flows through the crevasses and especially glacier mills to the glacier bed. This meltwater merges into streams and forms eddies at certain points. In these eddies, flow velocities of up to 200 km / h and high pressure prevail. The main erosion work with hollowing out the rock bed is done by the sand and gravel particles. The theory that a boulder rotating in the water cuts the glacier pot like a millstone out of the rock is considered out of date. Primarily it is the point of impact of a glacier mill, or local eddies in the base current of the subglacial water.
Occurrence
The largest glacier pots ( Norwegian jettegryter ) are naturally found where there are or were many and large glaciers. In Europe this is particularly the case in Scandinavia or in the Alps and their foothills. Many of these forms date from the Ice Age .
Glacier pots are widespread in the Alps, examples can be found in the Lucerne Glacier Garden , in the Weißbach Glacier Garden on the Alpine Road , where these washouts have a diameter of up to one meter, or in the Allgäu , where the very well-preserved Scheffau glacier pot in winter Was discovered during blasting work in 1896/1897. Glacier pots from the last Ice Ages can also be found in northern Germany, for example in the rock garden of Gommern in Saxony-Anhalt . At the beginning of the 19th century, several glacier pots were discovered in the quartzite quarries and given to the Magdeburg Natural History Museum .
In the center of Bad Gastein in Austria, several glacier pots can be seen, including one of oval shape with a diameter of 4.5 to 5.5 meters and a depth of 5 to 6 meters.
In Askola , Finland , the largest glacier pot has a diameter of four and a depth of ten meters.
literature
- Alexander Stahr , Thomas Hartmann: Landscapes and landscape elements in the high mountains. Springer, Berlin et al. 1999, ISBN 3-540-65278-7 , p. 289.
Web links
- Glacier pot in Blekinge (English)
Individual evidence
- ↑ Rock garden of Gommern ( Memento of the original from May 12, 2010 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ http://www.hiidenkirnut.fi/
