Clay minerals vertical profile

Vertisols Old weathered soils with uniform, thick, clay-rich profiles. Deeply cracked and hummocky topography produced by intense seasonal drying of expandable clay minerals such as smectites. Soil profile poorly developed because of vertical mixing caused by the seasonal cracking. High in exchangeable cations (base-rich). 

Bredehoeft JD, Papadopulos IS (1965) Rates of vertical groundwater movement estimated from the earth s thermal profile. Water Resources Research I(2) 325-328 Brown G, Brindley GW (1980) X-ray diffraction procedures for clay minerals identification. In Brindley GW, Brown G (eds) Crystal structures of clay minerals and their X-ray identification. Mineralogi-cal Society, London, pp 305-360... 

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