Colluvium is the name for loose bodies of sediment that has 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 interfingers with alluvium (deposits transported downslope by water).Coarse deposits due to rockfall at a cliff base are called talus and if lithified are talus breccias. Avalanches, mudslides and landslides are processes that deposit colluvium. Sediment is any particulate matter that can be transported by fluid flow and which eventually is deposited as a layer of solid particles on the bed or bottom of a body of water or other liquid. ... Scree or detritic cone is a term given to broken rock that appears at the bottom of crags, mountain cliffs or valley shoulders. ... Breccia, derived from the Latin word for broken, is a sedimentary rock composed of angular fragments in a matrix that may be of a similar or a different material. ...

Colluvium normally forms humps at the base of mountains or fan-shaped deposits similar in shape to alluvial fans that cover former ground surfaces. This process is an important phenomenon in the fields of archaeology and soil science. Many colluvial soils tend to have a fragipan associated with them that are a brittle subsoil layer typically high in clay. One theory of fragipan formation is the smearing of soil during the colluvial process causing the clays to seal the surface between the moving portion of soil and the stationary soil on which it slides. Ancient sites can be preserved beneath colluvium if later changes in the landscape such as deforestation encourage a downward movement of material. This build-up process is called colluviation. An alluvial fan is a fan-shaped deposit where a fast flowing stream flattens, slows, and spreads, typically at the exit of a canyon onto a flatter plain. ... Archaeology, archeology, or archæology (from the Greek words αρχαίος = ancient and λόγος = word/speech/discourse) is the study of human cultures through the recovery, documentation and analysis of material remains and environmental data, including architecture, artifacts, biofacts, human remains, and landscapes. ... Soil science deals with soil as a natural resource on the surface of the earth including soil formation, classification and mapping; physical, chemical, biological, and fertility properties of soils per se; and these properties in relation to the use and management of soils. ... An archaeological site is a place (or group of physical sites) in which evidence of past activity is preserved (either prehistoric or historic or contemporary), and which has been investigated using the discipline of archaeology. ... Deforestation is the conversion of forested areas to non-forested. ...