Colluvium

Colluvium is the name for loose bodies of sediment that have been deposited or built up at the bottom of a low-grade slope or against a barrier on that slope, transported by gravity. The deposits that collect at the foot of a steep slope or cliff are also known by the same name. Colluvium often grades into alluvium (deposits transported downslope by water). Coarse deposits due to rockfall at a cliff base are called talus (scree) and if lithified are talus breccias. Avalanches, mudslides, and landslides are processes that deposit colluvium. This build-up process is called colluviation.