Some Notes on Clay Minerals in Podzol Profiles in Fennoscandia

Montmorillonite is found to be a predominant clay mineral in the < 2/z fraction of the A2 horizon of podzol profiles in Fennoscandia, even when these are only 300 years old. Irt fractions between 2/ ~ and 20/ ~ vermiculite and. hydrobiotite predominate, but are rarely detected in the fraction coarser than 20/z. Vermiculite and hydrobiotite are also found in the finer fractions of the B horizon, but are only rarely detected in the C horizon where their presence is apparently due to contamination with inter-glacial or older products of weathering. The presence of kaolinite in some profiles is explicable in the same way.