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Changes in habitat conditions in a Late Glacial fluviogenic lake in response to climatic fluctuations (Warta River valley, central Poland)

Forysiak Jacek, Okupny Daniel, Obremska Milena, Antczak-Orlewska Olga, Płóciennik Mateusz, Pawłowski Dominik, Baradyn Daria, Kotrys Bartosz, Luoto Tomi P., Nevalainen Liisa, Borówka Ryszard K.

Geological Quarterly

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2023

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Vol. 67, No. 1

art. no. 1

EN

The Warta River valley was greatly influenced by the ice sheet of the Last Glacial Maximum (LGM). A small peatland located in the Warta drainage system is here used as a palaeoarchive of climatic and habitat changes during the Late Glacial (Weichselian). The Ługi sediment profile was investigated using multi-proxy (pollen, Chironomidae, Cladocera and geochemistry) analyses that recorded changes in a fluviogenic sedimentary depression. After the Poznań Phase (LGM), Ługi functioned as an oxbow lake that was cut off from the active river channel as a result of fluvial erosion. Since that time, the Warta River has flowed only along the section now occupied by the Jeziorsko Reservoir. Sedimentation of lacustrine deposits started at the beginning of the Late Glacial. Summer temperature reconstructions indicate cool Oldest and Younger Dryas, but no clear cooling in the Older Dryas. During the Younger Dryas the palaeolake was completely occupied by a peatland (fen), which periodically dried out during the Holocene. Investigation of this site has tracked the reaction of the habitat to climatic, hydrological and geomorphological changes throughout the Late Weichselian.

2

Postglacial palaeoenvironmental changesin the area surrounding Lake Udriku in North Estonia

Amon L., Saarse L.

Geological Quarterly

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2010

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Vol. 54, No 1

85-94

EN

Multiproxy data (plant macrofossils, AMS 14C radiocarbon dates, grain-size distribution, loss-on-ignition and magnetic susceptibility) from Lake Udriku Suurjärv in North Estonia were used to interpret local environmental changes during the postglacial period between 13 800 and 11 000 cal yr BP. Sediment lithology is complex but can roughly be described as silt overlain by silty gyttja, gyttjaand peat. The macrofossil diagram shows the local vegetation development from Late Glacial pioneer communities to early Holocenecommunities. The vegetation succession started predominately with Salix polaris, which was later replaced by Dryas octopetala. Thediversity of plant macrofossils increased significantly during the warmer part of the Allerod. Both the diversity and the number ofplant macrofossils are low in the Younger Dryas, confirming the severe climatic conditions found during this interval. During the LateGlacial to Holocene transition, aquatic taxa prevail among plant macrofossils. The absence of tree remains among macrofossils of thisperiod suggests that trees were not locally present or were not growing near the studied lake. Proxy data indicate several environmental changes. The sediment composition and vegetation reflect cooler and warmer episodes and confirm that the study area has been freeof ice since 13 800 cal yr BP.

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Lithology and palaeomagnetic record of Late Weichselian varved clays from NW Russia

Bakhmutov V., Kolka V., Yevzerov V.

Geological Quarterly

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2006

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Vol. 50, No. 3

353-368

EN

A lithological and palaeomagnetic analysis of Late Weichselian glaciolacustrine deposits from two ancient periglacial lakes was carried out in the valley of the Shuja (S Karelia) and Ust-Pjalka (S-E Kola Peninsula) rivers, NW Russia. The rhythmic structure of the varved clays is interpreted as turbiditic with systematic differences between the proximal and distal areas of accumulation. In the proximal area the textural and structural properties of the deposits towards both distal and (partly) lateral directions are described. It is shown that the proximal varve successions are incomplete while distally they are continuous. The accumulation of one varve (DE rhythm, second order cycle) during one year is consistent with palaeomagnetic data. Significant differences in magnetic parameters and in the palaeomagnetic "records" of declination-inclination between proximal and distal varves are established. Analysis of palaeomagnetic properties was combined with lithological analysis in all sections. Locally, the varved clays in the proximal area could be used for palaeomagnetic research. Taking into account the erosion of underlying deposits by turbidity currents and inclination shallowing, these sediments could not precisely record palaeosecular variation (PSV). The distal varved clays (represented by the DE rhythms) are clearly most useful both for varve-clay chronology and PSV recovery. The palaeomagnetic declination and inclination records are correlated with chrono- and magnetostratigraphy scheme of NW Russia. This paper also examines lithology-dependent "inclination error" and anisotropy of magnetic susceptibility in glaciolacustrine sediments.

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Simulation of the shorelines of glacial Lake Peipsi in Eastern Estonia during the Late Weichselian

Rosentau A., Hang T., Miidel A.

Geological Quarterly

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2004

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Vol. 48, No 4

299--307

EN

Digital reconstruction of the evolution of glacial Lake Peipsi, Eastern Estonia, was based on a geographic information system (GIS) method that removed isostatically deformed palaeowater planes fromthe current digital terrain model. A reconstruction of the proglacial water levels was performed with respect to geomorphological correlation of river terraces, raised shorelines and eroded surfaces of various aqueoglacial landforms. The configuration of shorelines, main outlets and water depths of glacial Lake Peipsi, corresponding to the Otepää, Piirissaar, Kaiu and Pandivere–Neva stades during the deglaciation of the Lake Peipsi depression, was simulated. The two approaches used, reflecting the geomorphological correlation of Raukas and Rähni (1969) and Hang (2001), are discussed.

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Stratigraphy of the section Antaviliai, eastern Lithuania, and its implication for the Upper Weichselian climatostratigraphic subdivision

Satkunas J., Hütt G.

Kwartalnik Geologiczny

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1999

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Vol. 43, Nr 2

213-218

EN

The Antaviliai section in eastern Lithuania was known so far as a site bearing sediments attributed to the Antaviliai Interstadial, placed stratigraphically between the Gruda (Brandenburg) and Ziogeliai (Frankfurt) Stadials. The section Antaviliai has been studied in 1989-1991 by the authors, including drilling of 6 boreholes, structural-textural examination and thermoluminescence datings of lacustrine sediments in the outcrop, lithostratigraphic identification of the overlying and the underlying tills. Assuming conditions of occurrence, palynological characteristics and thermoluminescence age, the Antaviliai Interstadial can be most likely correlated with the Drenthian-Warthian Interstadial. So far, in Lithuania as well as in other Baltic countries there is still not found any site with reliably determined the Upper Weichselian interstadial or interphasial deposits. Therefore stadials, phases and interstadials have no proper climatostratigraphic background in the Baltic states and the Late Weichselian at present can be subdivided only into lithostratigraphic units.

PL

Profil Antaviliai we wschodniej Litwie jest znany od dawna jako stanowisko z osadami interstadiału antaviliai, umieszczanego między stadiałami gruda (brandenburskim) i ziogeliai (frankfurckim) (P. Vaitiekunas, 1969). Został on zbadany przez autorów w latach 1989-1991. Wykonano wówczas 6 otworów wiertniczych, przeprowadzono badania strukturalne i teksturalne, w tym analizy litostratygraficzne podścielających i przykrywających glin zwałowych, oraz datowano metodą termoluminescencji osady jeziorne w górnej części odsłonięcia. Na podstawie sytuacji geologicznej, badań palinologicznych oraz datowań metodą termoluminescencji skorelowano interstadiał antaviliai z interstadiałem drenthe-warthe. Podobnie jak w innych państwach bałtyckich, na Litwie brak dotychczas stanowiska, w którym wiarygodnie stwierdzono by obecność osadów interstadialnych lub interfazalnych z młodszej części zlodowacenia wisły. Z tego powodu nie ma obecnie przesłanek klimatostratygraficznych do wyróżniania stadiałów, faz i interstadiałów w krajach bałtyckich, zaś młodsza część zlodowacenia wisły może być podzielona wyłącznie na jednostki litostratygraficzne.