colluvium
/kəˈl(j)uːvɪəm
/noun [mass noun] Geology
Material which accumulates at the foot of a steep slope.In the southern part of the valley, the Serghaya Fault Zone follows the mountain front juxtaposing recent alluvium and colluvium against late Quaternary lake sediments, Neogene conglomerates, and Cretaceous carbonates....
- Deposits formed on hill slopes are called colluvium where they are fine-grained, and taluvium if they are of coarse-grained rock debris.
- Archaeologists can use the evidence of pollen, alluvium (flood-deposits), and colluvium (hill-wash) to study the past environment.
Derivatives
colluvial
- A few hundred metres to the east, the trachy-phonolitic breccias, debris flows, colluvial and alluvial deposits of Agulo record the volcanic activity and the erosion of the east flanks of the Vallehermoso stratovolcano.
- Allochthonous sediments enter the cave system through a number of processes, including aeolian, fluvial, colluvial, biogenic, glacial, marine, and human activity.
- In addition, secondary topaz crystals, released from matrix by erosional forces, have been found in both alluvial and colluvial sediments adjacent to topaz-bearing pegmatites.
Origin
Mid 20th century: from Latin colluvies 'confluence of matter', from colluere 'to rinse', from col- 'together' + luere 'to wash'.