Environment and provenance in the development of recent alluvial deposits in epirus, nw greece

The valleys of Epirus, in NW Greece, are floored by alluvium laid down in historical times. In an attempt to evaluate the relative importance of diagenesis and of parent material in determining its local character, the alluvium was compared with the principal source deposits, namely the red beds of the late Quaternary Kokkinopilos Formation and the brown Mediterranean soils that have developed on flysch outcrops. Rehydration of the haematite pigment after deposition coupled with silt‐clay depletion during redeposition of the red beds is responsible for the drab colour of the valley‐floor deposits in limestone catchments. Where the alluvium was derived from brown soils, little mineralogical change has occurred. Some reduction and mobilization of iron has affected Kokkinopilos beds still in place, possibly during periods of seasonal waterlogging under oak forest, to produce a veining pattern akin to that found in pseudo‐gley soils.