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The deposition in an underlying soil layer of colloids, soluble salts, and mineral particles leached out of an overlying soil layer.

[illuvial, resulting from illuviation (in- + -luvial, relating to the action of flowing water, as in alluvial) + -ation.]


(Geological Science) the process by which a material (illuvium), which includes colloids and mineral salts, is washed down from one layer of soil to a lower layer
[C20: from Latin illuviēs dirt, mud, from il- + -luviēs, from lavere to wash]
ilˈluvial adj


(ɪˌlu viˈeɪ ʃən)

the accumulation in one layer of soil of materials that have been leached out of another layer.
References in periodicals archive ?
1983) can be applied to many pedogenic processes such as carbonate leaching from upper soil horizons and accumulation below, clay illuviation and podzolisation.
Buurman P, Jongmans AG, Pi-Pujol MD (1998) Clay illuviation and mechanical clay infiltration--is there a difference?
The SOC flow in the composition of organic matter begins with litter falling on or into the soil, continues with its disintegration, transformation into humus and accumulation, and ultimate disappearance, via consumption by soil organisms, complete mineralization or illuviation into the subsoil, or eluviation out of the soil cover.
In other areas, clay illuviation is less expressed or absent due to various causes which acted singly or jointly: recent water-deposited sediments, soil water excess, clay flocculation in calcareous materials or swell-shrink movements.
The soils of the study area are classified as Alfisols, characterized by a subsurface horizon in which silica has accumulated by illuviation (Brady and Weil 1996).
The Bm horizon may have any or all of the following characteristics: stronger chroma or redder hue than the underlying material, partial or complete removal of carbonates, slight illuviation of clay based mainly on the presence of an Ae horizon (E horizon in U.
The source of Si and Al extracted with NaOH may therefore be a mixture of poorly crystallised silicates (sources of Si and Al) and/or bio-opal (source of Si) transported downwards by processes such as illuviation and/or bioturbation (Saccone et al.
An argillic horizon occurs in Ultisols, since extensive illuviation has taken place, and a kandic horizon also occurs, since the CEC of that horizon is <16 [cmol.
More recent illuviation and/or lateral translocation of humus can be excluded due to the structure and composition of the outcrop as well as humus maturity (C : N = 14.
2010) have reported illuviation features (argillans or illuviated clay cutans) in cohesive soils from different parts of Brazil (Pernambuco and Alagoas), their presence has either not been recognised in many soils or has been observed in small quantities (Melo and Santos 1996; Lima et al.
Over millennia clay has accumulated in the subsoils as a result of weathering of primary minerals and clay illuviation.