“The interval from 66-112 cm is also now part of the BC horizon of the surface soil and an illuvial horizon of the fragipan.”

“Soil texture is silty in the eluvial horizons and clayey in the illuvial horizons.”

“The illuvial soil horizon B is marked by increased concentrations of lead and copper.”

“In the deeper horizons where the pH decreases and with the accumulation of illuviated clay, the aggregates are more stable and persist.”

“The site has thick clayey soils, with subsurface horizons stiff with illuviated clay.”

“The purpose of this study was to determine if elements other than Al and Fe are chelated by soil organic matter and illuviated to deeper soil horizons.”