Colluvium specific geological setting. Alluvium is sand, clay, or other similar detrital material deposited by running water. The distinction between colluvium and alluvium relates to the involvement of running water. Alluvium specifically refers to the geomorphic processes involved with flowing water and so alluvium is generally fine-grained clay and silt material that has the capacity to be entrained in water currents and eventually deposited. For these same reasons, alluvium is also generally well sorted material while colluvium is not. Colluvium Colluvium (also colluvial material or colluvial soil) is a general name for loose, unconsolidated sediments that have been deposited at the
Polish Soil Classification effect of specific groups of soil forming processes. Soil types are divided into subtypes. Geological origin of bedrock described by "rodzaj gleby" describes geological origin and properties of material from which the soil was formed. It is not the same as soil family from USDA Soil Taxonomy. Examples can be: granitoid, basalt, amphibolite, sandstone, limestone (with specified period of formation), gypsum, glacial till, sandur sand, loess and others. Sizes of soil particles and texture of soil material are very similar to USDA classification. It makes possible correlating results of particle size analysis of soils described using USDA and Polish Soil