A high-resolution analysis of the Zmajevac loess-palaeosol sequence in East Croatia (Baranja) was performed with the purpose to get new insights into the palaeoenvironmental history during the last ...three glacial-interglacial cycles. The post-IR infrared stimulated luminescence signal of feldspar, stimulated at 290°C (thereafter pIRIR290) was used to establish a reliable chronological framework and revealed intensive sedimentation during (at least) the last 300 kyr, which was five times interrupted by climate optima resulting in the formation of soils (now palaeosols). The environmental magnetic measurements support the obtained luminescence chronology. Further chronological time control was reached by age modelling based on tie points from variations in frequency dependence of magnetic susceptibility and benthic δ18O variations from the LR04 stack of Lisiecki and Raymo (2005). The grain-size record provided information about the environmental conditions and dust accumulation. Additional palaeoenvironmental implications were provided by room temperature magnetic susceptibility and colourimetric analyses and revealed a continuously lower intensity of pedogenesis, coupled with constantly decreasing temperatures and precipitation from the oxygen isotope stage (OIS) 9 to the end of OIS 3. X-ray diffraction of the clay mineral fraction revealed chlorite, smectite and illitic material as dominant mineral phases. While clay minerals from loess are mostly detrital, smectite from palaeosols is partly of a pedogenic origin. The application of our multi-proxy approach, including relative and numerical dating techniques, provided new insights into a highly resolved terrestrial paleoenvironmental record of Eastern Croatia.
•Post-IR IRSL chronology of the Zmajevac loess-palaeosol sequence is presented.•Age modelling based on environmental-magnetic and colorimetric data was performed.•Grain-size analysis and EMM imply to the provenance of the material.•U-ratio indicate differences in wind intensity.•Glacials show instability of prevailing wind regimes compared to the interglacials.•MS and colourimetric data indicate strong decrease of summer heat and seasonality.
Stream sediment is widely used as a medium in geochemical surveys. This study examined major element chemical composition of stream sediment produced by weathering in lithologically diverse terrain. ...Such sediment represents mixed sediment, therefore, the aim was to interpret its provenance and model the transitions within its major element composition. The particular interest was to link major element composition, mineral composition and the sediment source rocks. In order to interpret the sediment origin principal component analysis was employed and representative samples with highest and lowest scores were analysed for mineral composition. Scores also suggested four lithology-based groups of stream sediment samples. Transitions between groups were described with linear models for compositional data. Despite the ambiguity, links between major element composition, mineral composition and provenance were established. Besides sorting out sources of mixed sediment and minerals which control the transitions, this study contributes to general understanding of the Psunj Mt. geology, while the results can be used in geochemical surveys in areas of a similar geological setting.
•Provenance of stream sediment from the Psunj Mt. is interpreted.•Transitions in chemical compositions are modelled.•Links between major element and rock-forming mineral compositions are established.•Compositional data statistical methodology is employed.
The Pannonian Basin System (PBS) and associated parts of the surrounding orogens (SOs) were selected for a regional geochemical mapping of concentrations of potentially toxic metals, with the sample ...media the topsoil horizon. Geochemical data form a sample space that is different from Euclidean, and therefore standard statistical methods are not applicable for such data. To apply standard statistical methods, data were transformed to Euclidean space by using a special case of an isometric log-ratio transformation for a composition consisting of two parts (the first part is the metal concentration of interest; the second part is the total concentration of all other elements in the composition). Estimations were performed using deterministic (Ordinary Kriging) and stochastic (sequential Gaussian simulations (SGS)) methods. The resulting maps provide insight into the distribution of certain metals in the PBS and associated parts of the SOs, and are intended to serve as base maps for further studies. The maps obtained with SGS provide additional information on the variability (uncertainty) of estimation.
Soils from an industrial zone in Garešnica, Croatia have been analysed by EDXRF and XRD. In the area surrounding two adjacent factories named 'Bakrotisak' and 'Croatia Protekt', thirty soil sites ...(depth 5-15 cm) were sampled in December 2007, together with five soil sites from the forest (check samples) situated 0.5 km away. The locality was selected for its periodical, industrially induced environmental pollution which affects nearby streams and fish ponds, resulting in occasional fish kills in the region. Analysis included the determination of the soil mineralogy, total organic matter contents, cation exchange capacity, bulk multi-element composition and heavy metal levels in leachates (exchangeable fraction). Multi-element concentrations in the check samples constituted natural levels based on their perfect normal distributions. The Kruskal-Wallis test showed higher, statistically significant (P = 0.0005) concentrations of Cu in the soil surrounding 'Bakrotisak' compared to the check samples. Furthermore, leaching analysis confirmed the copper contamination of the 'Bakrotisak' soil by highly significant positive correlation (the Kendall's Tau correlation coefficient >0.99) between its extractable Cu and total Cu levels. Moreover, enrichment factors based on Al as a reference element were found to be >2 for approximately 50% samples of the 'Bakrotisak' soil, suggesting its moderate anthropogenic contamination.
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