Hanging is a mining - geological location designation for rock that overlies a reference layer. The hanging wall does not necessarily have to be younger than the reference horizon. The term has a slightly different meaning in the various geoscientific disciplines. The location designation for rock underlying a reference horizon is lying .
Engineering geology and mining
Hang end is in mining the name for over a seam deposited rock layers or for the above a deposit lying mountains . Today's storage is in the foreground; Due to tectonic processes, the hanging wall can in rare cases be older than the reference horizon.
The hanging rock also forms the stabilizing ceiling (the ridge , the tunnel roof ) over a corridor or the tunnel in a mine or pit , which then unlocks the deposit. If the hanging wall is unstable - for example as a result of intersecting fissures - rock blocks can suddenly fall out of the layer structure and cause serious accidents (see collapse and coffin lid ).
At least in historical mining, the terms hanging and lying were also used in mining on ore veins and thus referred to the adjacent rock. In the case of steeply plunging ore veins, hanging and lying areas did not form the roof and bottom, but the - more or less inclined - side surfaces of a tunnel or a route.
In mining, overburden is the name given to the totality of the hanging wall, from the standing on the seam or tunnel to the surface of the earth . "Mountains" is the mining word for rock in general. In the open pit it is removed as overburden .
In geology, the term hanging wall is usually understood in a more general way. But here, too, the term is applied to quite different positional relationships:
- Hanging is the sequence of rocks that topographically lies above a certain horizon or a particularly geologically interesting layer;
- the rock layer ( hanging wall ) that is located directly above a shear zone or a fault . The layer below is Liegendes (footwall) .
- Large-scale thrusts (tectonic nappes) are also referred to as lying and hanging nappes or hanging and lying nappes.
- If the term is specified as “stratigraphic hanging wall”, it is expressed that the hanging wall is actually younger than the reference layer.
- The term lying fold has nothing to do with this mining-geological position relationship (see lying ), but simply means that a fold has overturned and lies on the sub-base. In the ideal lying fold, the two legs of the fold run approximately parallel to the base, in reality mostly at an acute angle or differently acute angles. On the other hand, the term hanging leg (a lying fold) is used again in the positional relationship described here. It refers to the upper leg of a lying fold.
The use of the terms “hanging wall sections” or “hanging wall layers” for the higher part of a layer sequence is not recommended. So you should z. B. do not speak of the “hanging wall parts” of an xy formation if the upper (or higher lying) parts of the formation are meant. The terms only mean the overlying layers of a layer sequence, that is to say also the layers overlying the formation.
- Lexicon of Geosciences. Edu to Inst . 506 pp., Spektrum / Akademischer Verlag, Heidelberg 2000 ISBN 3-8274-0421-5
- Hans Murawski / Wilhelm Meyer: Geological dictionary . 10., rework. u. exp. Ed., 278 pages, Enke Verlag, Stuttgart 1998. ISBN 3-432-84100-0 .
- Walter Bischoff , Heinz Bramann, Westfälische Berggewerkschaftskasse Bochum: The small mining dictionary. 7th edition, Verlag Glückauf GmbH, Essen, 1988, ISBN 3-7739-0501-7
- Heinrich Veith: German mountain dictionary with evidence. Published by Wilhelm Gottlieb Korn, Breslau 1871.
- Württembergische Bergordnung of 1598, Part 2, Art. 8; quoted from Hoffmann, CHC [correct: Karl Heinrich Ludwig]: Collection of Württemberg Finance Laws, Part 1, Dept. 1. (Reyscher, Albert Ludwig (ed.): Collection of Württemberg Laws, Vol. 16, Part 1, Dept. . 1), Tübingen: Fues, 1845, p. 142.
- Lexicon of Geosciences (2000: p. 401).
- Murawski & Meyer (1998: p. 91).