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Geochemical and Mineralogical Characteristics of Loess/Paleosoil Sequence from Zmajevac, Baranja, Croatia

At the section at Zmajevac, Baranja, in Croatia a very detailed Upper Pleistocene loess record about 28 m thick is exposed including six loess horizons, alluvial sediments and five intercalated paleosols. Infrared Optically Stimulated Luminescence (IRSL) dating provides a chronological frame for the loess/paleosol sequence and enables the correlation with other central and southeastern European localities. The profile represents one of the best sections in the study area for reconstructing sedimentological and paleoclimatic events that caused such a dynamic geological setting. The age determination of the loess sediments between the paleosols using IRSL provides a more reliable base for identification of the soil forming periods. Geochemical (contents of major and trace elements and REE, together with TOC, pH, CaCO3 content) and sedimentological (grain size, lamination, microscopic characteristic of carbonate concretions) characteristics of investigated paleosols showed the main characteristics and degree of pedogenesis, while differences in composition of heavy and light mineral fraction emphasized variations in source material for the sediments under investigation. Presence of erosional discontinuities and infilling of crotovinas with no other signs of paleosol may indicate that some of paleosols are eroded, suggesting an incomplete record. Ten samples were studied from the Zmajavac section by an IRSL dating approach applying the multiple aliquot additive dose (MAAD) protocol. An IRSL age estimate of 17.8&plusmn ; 1.9 ka indicates an increased accumulation of dust during the Late Glacial/Pleniglacial, as elsewhere in Europe. The preliminary IRSL results indicate most likely a soil formation during interstadial of marine isotope stage 3, as indicated by IRSL age estimate of 61.0&plusmn ; 6.2 ka from a sample taken below the uppermost palaleosol. More dating results are available shortly and will be discussed during the presentation

paleosol; loess; mineralogy; geochemistry; Pleistocene; Croatia

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