Wskaźniki obecności paleogleb w neogeńskich iłach poznańskich okolic Leszna w południowej Wielkopolsce

This paper presents the results of a study on the pedogenic alteration of Neogene terrestrial Poznań Clays near Leszno, central-western Poland. Samples of clays and carbonate concretions were collected from drillcore of the Leszno Zaborowo borehole (64 m thick) and analysed by optical microscopic, XRD, isotopic, and chemical methods. Our findings reveal multiple indicators of soil-forming processes that significantly altered the clays. These include the massive structure of the sediment, localized slickensides, a beidellite-dominated mineral composition, and the presence of numerous siderite and calcite concretions exhibiting characteristic pedogenic textures. The isotopic compositions of these carbonates range from 613C = -18.54 to -6.73%o and 618O = -5.21 to -1.56%. These data confirm that the carbonates crystallized as a result of organic matter decomposition by anaerobic microorganisms in a terrestrial environment.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).