Stream capture
A Flussanzapfung occurs when a river moved toward the other and this ( literally ) " abgräbt the water ". The watershed is broken here and shifted: the tapped flow atrophied below the Anzapfungsstelle, there may develop a dry valley, while the other is its amount of water increases with the extraneous water.
An unusually strong flow deflection can be interpreted as an indication of such a process - it is denoted as Anzapfungsknie.
Tap and distraction
As a tap in the strict sense only relatively sudden events are seen, long -term geodynamic processes and their hydrographic impact we group in the modern literature, the term river diversion together. In fact, the " suddenness " in geological time is always be treated with caution and often consists of several intermediate stages.
Causes
For the Flussanzapfung several causes can fix that work together overlapping processes can represent in the geological development that have led to today's rivers:
- Tectonic uplift or subsidence: An area, for example, so raised that the river this can not overcome.
- Aufschotterung: Due to reduced flow rate or meandering so much gravel is deposited in the river bed that is lifted and finally a previously insurmountable obstacle ( watershed ) may be included here (see eg Feldberg Danube ).
- Re border erosion: By material removal, the river to its source cuts down into the subsoil, which may result in special cases to Flussanzapfung.
- Glacier storage: Here, most glaciers form reservoirs that erupt out a survey and establish their new water gap before they regress by glacier retreat again.
- Karst seepage: bleed in the source horizon. In the underground water seeps into a foreign source area.
- Moor infiltration: In large shallow river swamps and the outside that do not lie in a orographic valley real bifurcations can occur. Tectonic and erosive forces can shape it into later real taps.
A " modern" form occurs in the water power plant, where it is fed by tap water of a river basin a remote power station. A drying up of the river can only be counteracted by residual water transfer. In this power plant is anchored by law or contract; where it is absent ( major projects outside the industrial countries ), large-scale hydrological changes can occur.
Examples
- Wutach deflection of the ancient Danube ( Donau Feldberg ) in the Wutachschlucht whose Anzapfungscharakter is not safe
- Donauversinkung in Tuttlingen, where water is drawn off in the underground in the Aachtopf the Rhine
- Pair breakdown in Friedberg- Ottmaring where the originally parallel to the Lech running couple bends to the northeast and leaves the Lech Valley
- Infiltration of Hönne in Sauerland
- Bridged Donknie and Volga bend in Volgograd by raising the threshold and the Volga Jergeni Hill in Kazakh Valley, today through the Volga - Don Canal