Colluvium is a general name for loose, unconsolidated
sediments that have been deposited at the base of hillslopes by either rainwash, sheetwash, slow continuous
downslope creep, or a variable combination of these processes. Colluvium is typically composed of a heterogeneous range of rock types and sediments ranging from
silt to
rock fragments of various sizes. This term is also used to specifically refer to sediment deposited at the base of a hillslope by unconcentrated
surface runoff or sheet
erosion.