Psamment
In USDA soil taxonomy, a psamment is defined as an entisol which consists basically of unconsolidated sand deposits, often found in shifting sand dunes but also in areas of very coarse-textured parent material subject to millions of years of weathering. This latter case is characteristic of the Guiana Highlands of northern South America. A psamment has no distinct soil horizons, and must consist entirely of material of loamy sand or coarser in texture. In the FAO soil classification, psamments are known as arenosols.