Scree (to roll ) is made of stones , so rock rubble that during transport by water , landslides , mudflows be moved or other ground movements to the valley and their broken edges here were more or less rounded.
The size of the stones is mainly between 2 and 20 centimeters, according to DIN 4022 rubble is larger than 63 mm, generally at least larger than 2 mm ( psephite ), block rubble is larger than house size. Smaller grain sizes are called gravel and sand .
In principle, one differentiates
- fluvial rubble : near the water, its movementcan be heardas a soft trickle or singing . It often forms large gravel or gravel banks , which are important raw materials for the building industry due to their uniform composition of grain sizes. Individual large blocks are called Schroppen there . Smaller pebbles are known in southern Germany and beyond as Wacken .
- marine rubble ( surf rubble)
- Rubble , the mixed form of rubble and rubble, which is deposited as a foot ( talus ) around rock towers , along the rock walls and in karen and steep valleys - these lie at the rubble boundary angle, fresh quarry cannot stay and rolls down to the valley as rockfall . In itself, the talus is slowly moved further through frost work.
- Riesel fluh , rubble connected by loose earth
- pyroclastic boulders .
- Scree deserts : They are formed from passive wind sediments that are created from previously sharp-edged fragments of rock (transformed into abraded scree) due to the corrosive effects of wind and sand.
- Reading stones : individually lying stones and blocks that have no connection to the rock .
If the material sediments and solidifies , a conglomerate is formed (in contrast to the angular breccia ). Therefore, pebbles belong to the clastic sediments . A special form of such rocks are the tillites .
- Example of a rubble collection at the University of Düsseldorf
- Radim Kettner : General geology. Volume 2: Composition of the earth's crust, formation of rocks and deposits. VEB Deutscher Verlag der Wissenschaften, Berlin 1959, pp. 81–83.
- Radim Kettner: General geology. Volume 3: The external geological forces, the earth's surface and the geological activity of water. VEB Deutscher Verlag der Wissenschaften, Berlin 1959, pp. 9–12, 108–109.
- Radim Kettner: General geology. Volume 4: The external geological forces, the earth's surface and the geological activity of ice, wind, gravity, organisms and humans. VEB Deutscher Verlag der Wissenschaften, Berlin 1960, pp. 131, 156–157.
- Ludwig Pfeiffer, Manfred short, Gerhard Mathé: Introduction to petrology. Akademie-Verlag, Berlin 1981, pp. 246, 251.
- Rieselfluh. In: Jacob Grimm , Wilhelm Grimm (Hrsg.): German dictionary . tape 14 : R - skewness - (VIII). S. Hirzel, Leipzig 1893, Sp. 936 ( woerterbuchnetz.de ).
- Kettner, Volume IV
- Paul-Armand Gette: Comparison of scree of the White and Red Saar . 2nd Edition. AQ-Verlag, Saarbrücken 2013, ISBN 978-3-922441-05-2 .