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Environmental changes during the MIS 6a–MIS 5e transition : the Parchliny 2016 profile, central Poland

Majecka Aleksandra, Wachecka-Kotkowska Lucyna, Krzyszkowski Dariusz, Malkiewicz Małgorzata, Mirosław-Grabowska Joanna, Niska Monika, Rzodkiewicz Monika, Myśkow Elżbieta, Tomaszewska Klara, Wieczorek Dariusz, Raczyk Jerzy

Geological Quarterly

2022

Vol. 66, No. 4

art. no. 31

We describe the penultimate glacial – last interglacial transition from the one of the numerous palaeolake successions in central Poland, which have yielded many documented Eemian and Early Weichselian floral records. In the new profile, Parchliny 2016, the lacustrine deposits were analysed lithologically, botanically, zoologically, and geochemically, providing new data that illustrate the environmental transition from the Late Saalian (MIS 6a) to the Eemian interglacial (MIS 5e). Five phases of palaeolake development have been distinguished. The first phase was related to the rapid melting of a dead ice block buried in the tills to form a lake. The second phase documented a Late Saalian initial succession, with the dominance of open steppe communities (Stadial 1), followed by a third phase with gradual increasing density of vegetation, the spread of boreal forests (Zeifen interstadial) and further increase in open communities and the retreat of pine (Kattegat stadial). The fourth phase reflected the beginning of Eemian interglacial by the expansion of pioneering birch-pine and purely birch forests and an increasing proportion of deciduous trees, including oak (Vth phase). Diatom, cladoceran and geochemical studies indicate at least two stages of lake development. The first stage (Late Saalian) was of an open lake (2–4 m deep), in relatively cold conditions and nutrient-poor water with the lowest amounts of organic carbon and nitrogen. The second stage (Eemian interglacial), shows warmer, shallower conditions in which the lake’s primary production increased, the water was well oxygenated, and there were more trophic levels.

Chronostratigraphy of Late Glacial aeolian activity in SW Poland – A case study from the Niemodlin Plateau

Moska Piotr, Jary Zdzisław, Sokołowski Robert Jan, Poręba Grzegorz, Raczyk Jerzy, Krawczyk Marcin, Skurzyński Jacek, Zieliński Paweł, Michczyński Adam, Tudyka Konrad, Adamiec Grzegorz, Piotrowska Natalia, Pawełczyk Fatima, Łopuch Michał, Szymak Agnieszka, Ryzner Kamila

Geochronometria

2020

Vol. 47, no.1

124--137

The stratigraphy of Late Pleniglacial and Late Glacial fluvio-to-aeolian succession was investigated in two sites located at the Niemodlin Plateau, SW Poland. Lithofacial analysis was used for the reconstruction of sedimentary environments. An absolute chronology for climatic change and the resulting environmental changes were determined based on optically stimulated luminescence (OSL – nine samples) and radiocarbon (three samples) dating methods. Four phases of changes in sedimentary environments were established. The first depositional phase correlates with the Last Permafrost Maximum (24−17 ka) based on the type and size of the periglacial structures, which aggraded under continuous permafrost conditions. During 17.5−15.5 ka (upper Late Pleniglacial), a stratigraphic gap was detected, owing to a break in the deposition on the interfluve area. The second depositional phase took place during 15.5−13.5 ka. During this phase, the first part of the dune formation (Przechód site) and fluvio-aeolian cover (Siedliska site) was deposited. The sedimentary processes continued throughout the entire Bølling interstadial and Older Dryas. In the third phase (Allerød interstadial), soil formation took place. At the Siedliska site, palaeosol represented Usselo soil type, whereas at the Przechód site, there was a colluvial type of soil. The last phase (Younger Dryas) is represented by the main phase of dune formation in both sites. After the Younger Dryas, no aeolian activity was detected. High compliance with both absolute dating methods was noticed.