Sand pit
The extraction of sand from the uppermost sediment layers in open-cast mining is referred to as a sand pit , sand mill , sand pit or sand wash . The degraded materials among the mass of raw materials of the construction industry .
Suitable places for sand pits can be found in the lower reaches of wide valleys and in river plains , where the gradient of the river is already low and a large proportion of crushed stone or gravel can no longer be deposited. There are also numerous sand pits in the molasse zone of the Alpine foothills . Likewise in the North German Plain , where the Pleistocene inland ice deposited large amounts of sand and gravel.
The excavation can be done with different types of excavators , but also manually (with a shovel ) for loose sand and small quantities . In various places, archaeologists have come across sand pits from the Stone Age .
In contrast to gravel and gravel pits , sand pits do not fill so significantly with groundwater after mining has ended , because the hydrological conditions are different and the slopes are more prone to landslides than with solid rock. Notwithstanding the mining distinction is spoken in both cases of Stretch .
Drained excavation pits as well as abandoned pits are mostly of particular ecological and nature conservation interest in the - intentional as well as natural - renaturation as special locations. In addition, more attractive remains can also be used for recreational purposes.
literature
- Jacob Stoller: Geological guide through the Lüneburg Heath. Springer Fachmedien, Wiesbaden 1918.
Web links
- Requirement for gravel and sand, approval and reuse of sand pits and gravel pits
- Sand pits in Upper Franconia (accessed November 7, 2019)
- Quartz raw materials in Germany (accessed on November 7, 2019)
- Extraction of mineral raw materials (accessed on November 7, 2019)
- The subsurface near the surface in the Rhein Main landscape (accessed on November 7, 2019)
See also
- Sand , silt , gravel , grain size
- Sandl , sand castle , building material , molasses