Weathering variability and aluminium interlayering: clay mineralogy of podzol profiles in till and glaciofluvial deposits, SW Sweden

Clay mineralogy is used as a reflection of trends in soil profile development in till and glaciofluvial deposits in SW Sweden. A major weathering products is vermiculite. Smectite occures in E horizons at sites with low pH and where soil mineralogy provided less acid neutralization through weathering. Low pH conditions have caused Al leaching and subsequent precipitation as hydroxy-Al interlayers in vermiculite. Changes in Al-interlayering between soil horizons have been evaluated by calculating a gravity centre of the clay mineral peaks on XRD spectra, which change in response to K-saturation and heating. The presence of interlayers has an important effect upon the cation exchange capacity of vermiculite.