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Stratigraphic chart of Leninsk section (a) and its location in the Russian Northern Caspian lowland (b) (modified after K€ oltringer et al., 2020). The extend of the last glacial maximum ice sheet is shown after Arkhipov et al. (1995).

Stratigraphic chart of Leninsk section (a) and its location in the Russian Northern Caspian lowland (b) (modified after K€ oltringer et al., 2020). The extend of the last glacial maximum ice sheet is shown after Arkhipov et al. (1995).

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Magnetic fabric (MF) investigations complemented by geochemical and grain surface analyses of the understudied and controversial marine isotope stage (MIS) 5 b, 4 and 3 loess deposits in the Lower Volga region, Russia show that the material has been transported and deposited by wind and to a large extent experienced post-depositional reworking. Gra...

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... Lower Volga region is located within the large plain of the Northern Caspian lowland in the south of Russia (Fig. 1). Loess deposits crop out in sections along incised gullies, river and stream channels in this area, typically representing the classic regional stratigraphy, including marine deposits from two Caspian Sea transgressions (Khazarian and Kvalynian) and continental ones from the intervening regression phase (Atelian) (e.g. Yanina, ...
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... comprises of two natural outcrops: the 14 m thick LN1 and the underlying 3 m thick LN2, which stratigraphically follows below the deeper part of LN1, 350 m further south in a dry gully. The Leninsk stratigraphy comprises fluvial deposits at its base, followed by the loess sequence, which is unconformably separated from overlying marine deposits (Fig. 1), in line with the regional stratigraphic model. A stratigraphic description of Leninsk and the detailed rock magnetic analysis of the sequence can be found in K€ oltringer et al. (2020), who reinforce that the loess at Leninsk represents an aeolian accumulation of fine-grained material based on its sedimentological and magnetic ...
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... AMS parameters: "regular" AMS unit (R); pedogenic AMS unit (P1, P2, P3); "irregular" AMS unit (IR1, IR2, IR3, IR4, IR5, for detailed information about the magnetic fabric characteristics of the groups please see Chapter 4.1). The 3 samples from wedge infill material are not included to the curves but displayed as X symbols. For chart legend see Fig. 1. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.) parameters are rather similar (Supp. Table ...
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... test the influence of the paramagnetic phase on the AMS, hysteresis magnetisation parameters are used. The saturation magnetisation (Ms) of pure magnetite is 92 Am 2 kg À1 (Hunt et al., 1995), the highest measured Ms of loess at Leninsk is 0.011 Am 2 kg À1 (data from K€ oltringer et al., 2020), which suggests that if the ferrimagnetic mineral fraction were purely magnetite, the maximum weight percentage of magnetite in samples from Leninsk would be only 0.012. This small percentage demonstrates that, even if distribution anisotropy of magnetite played a role, magnetic lineation is not caused by any ferrimagnetic particle interaction, but rather the alignment of the paramagnetic components in phyllosilicates together with the alignment of the subordinately present ferrimagnetic minerals. ...
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... deposition of the loess (indicated by conchoidal fractures). As such, this seems consistent with the silt/sand material of LVL originating from the north of the East European Plain (EEP), where the Fennoscandian Ice Sheet produced large amounts of fine grained, silt sized till material during the last glaciation, during which the LVL accumulated (Fig. 1). This glacial material formed proglacial outwash deposits that were transported south by river systems and ultimately into the Volga River. In turn, this Volga alluvium is likely to be the sedimentary source for the aeolian transported LVL deposits. The potential impact of cryogenesis on the mechanical surface microtexture of grains is ...
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... from the past 30 years measured at 10 m and 100 m height during December, January, February (winter) and June, July, August (summer) were analysed for the northern Black Seae Caspian Sea region as well as for the ERA5 reanalysis' closest grid point to Leninsk. Average wind speeds during winter are significantly higher than during summer (Supp. Fig. 1a, b, e, f, g, h, 2, and 3) and predominantly blow from the WSW and ESE at Leninsk (Supp. Fig. 1c, d, e, f, g, and h). By contrast, dominant summer winds tend to blow from the NE and NW. Winds at 100 m height show clearly stronger speeds than at 10 m but no differences in wind direction are apparent (Supp. Fig. 1c, d, e, f, g, and h). ...
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... and June, July, August (summer) were analysed for the northern Black Seae Caspian Sea region as well as for the ERA5 reanalysis' closest grid point to Leninsk. Average wind speeds during winter are significantly higher than during summer (Supp. Fig. 1a, b, e, f, g, h, 2, and 3) and predominantly blow from the WSW and ESE at Leninsk (Supp. Fig. 1c, d, e, f, g, and h). By contrast, dominant summer winds tend to blow from the NE and NW. Winds at 100 m height show clearly stronger speeds than at 10 m but no differences in wind direction are apparent (Supp. Fig. 1c, d, e, f, g, and h). Higher wind speeds during winter than summer are also reported by Ibrayev et al. (2010), while their observations of ...
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... higher than during summer (Supp. Fig. 1a, b, e, f, g, h, 2, and 3) and predominantly blow from the WSW and ESE at Leninsk (Supp. Fig. 1c, d, e, f, g, and h). By contrast, dominant summer winds tend to blow from the NE and NW. Winds at 100 m height show clearly stronger speeds than at 10 m but no differences in wind direction are apparent (Supp. Fig. 1c, d, e, f, g, and h). Higher wind speeds during winter than summer are also reported by Ibrayev et al. (2010), while their observations of modern winter and summer wind directions, similar to those discussed by Rodionov (2003), demonstrate prevailing southerlies during winter and northerlies during summer. However, the observations above for Leninsk show ...
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... while their observations of modern winter and summer wind directions, similar to those discussed by Rodionov (2003), demonstrate prevailing southerlies during winter and northerlies during summer. However, the observations above for Leninsk show some differences to this pattern, particularly in winter when a more W-E component stands out (Supp. Fig. 1). When modern wind patterns for winter are plotted over a wider area, the influence of local topography on wind direction at Leninsk becomes clear (Supp . Fig. 2). The valleys of the Volga and Don river, and the Manych depression are characterized by lower wind speeds. The Yergeni uplands (the topographic high between the depressions ...
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... NeS and SeN winds, topographic conditions modify this wider pattern so that winds at Leninsk have a stronger zonal component (W-E and E-W). There is a strong apparent similarity between present and our reconstructed Late Pleistocene dominant wind directions at Leninsk. The modern wind regime in winter shows a strong west to east component (Supp. Fig. 1), which seems to be also one of the dominant wind directions in the AMS data (Fig. 9c). This matches observations of Nawrocki et al. (2018) for Ukrainian Black Sea loess, where the reconstructed NW-SE palaeowind directions also coincide with present-day winds. On a wider regional scale, palaeowind studies from Siberian loess fit these ...
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... maximum show prevailing north-westerlies (36% of the time) and westerlies (22% of the time) in the Northern Caspian lowland ( Schaffernicht et al., 2019). These model predictions are consistent with AMS-derived palaeowind reconstructions for Leninsk ( Fig. 9) and leads to the reconstructed palaeowind pattern for the Late Pleistocene shown in Fig. 10. It is inferred that prevailing westerlies and north-westerlies dominated south of the Fennoscandian Ice Sheet (Fig. 1), forcing the local southerly winter winds in the Caspian Sea region further south (Fig. 10). The local topography leads to a decrease of windspeed in valleys and deflects the wind direction along large river valleys ...
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... lowland ( Schaffernicht et al., 2019). These model predictions are consistent with AMS-derived palaeowind reconstructions for Leninsk ( Fig. 9) and leads to the reconstructed palaeowind pattern for the Late Pleistocene shown in Fig. 10. It is inferred that prevailing westerlies and north-westerlies dominated south of the Fennoscandian Ice Sheet (Fig. 1), forcing the local southerly winter winds in the Caspian Sea region further south (Fig. 10). The local topography leads to a decrease of windspeed in valleys and deflects the wind direction along large river valleys such as the Volga valley and the Manych depression (Fig. 10). Furthermore, wind intensity appears to have been strongest ...
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... palaeowind reconstructions for Leninsk ( Fig. 9) and leads to the reconstructed palaeowind pattern for the Late Pleistocene shown in Fig. 10. It is inferred that prevailing westerlies and north-westerlies dominated south of the Fennoscandian Ice Sheet (Fig. 1), forcing the local southerly winter winds in the Caspian Sea region further south (Fig. 10). The local topography leads to a decrease of windspeed in valleys and deflects the wind direction along large river valleys such as the Volga valley and the Manych depression (Fig. 10). Furthermore, wind intensity appears to have been strongest at Leninsk during the early part of loess deposition associated with late MIS 5 and MIS 4, ...
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... and north-westerlies dominated south of the Fennoscandian Ice Sheet (Fig. 1), forcing the local southerly winter winds in the Caspian Sea region further south (Fig. 10). The local topography leads to a decrease of windspeed in valleys and deflects the wind direction along large river valleys such as the Volga valley and the Manych depression (Fig. 10). Furthermore, wind intensity appears to have been strongest at Leninsk during the early part of loess deposition associated with late MIS 5 and MIS 4, with less intense flow under MIS 3 conditions recorded higher up in the sequence (Fig. 3, L and Pj parameters). Again, this result is consistent with stronger winds in modern wintertime ...
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... to have been strongest at Leninsk during the early part of loess deposition associated with late MIS 5 and MIS 4, with less intense flow under MIS 3 conditions recorded higher up in the sequence (Fig. 3, L and Pj parameters). Again, this result is consistent with stronger winds in modern wintertime at the site and over the wider region (Supp. Figs. 1, 2). As suggested by K€ oltringer et al. (2020) and inferred also from palaeosol-loess records in the neighbouring Azov Sea region, MIS 4 was the coldest phase of the last glaciation in the area ( Liang et al., 2016) and wind intensities were generally the strongest (Novothny et al., ...
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... suggested climate evolution is also supported by the palaeowind reconstructions, indicating stronger winds associated with cooler temperatures during early MIS 4. The overall prevailing wind direction during the Late Pleistocene at Leninsk was variable but dominantly W-E and NW-SE (Fig. 10), although a denser sampling resolution in depth would be beneficial to disentangle the predominance and variation of wind directions over time. Reconstructed palaeowinds at Leninsk are similar to the present-day situation but the presence of several factors such as locally influenced winds plus wider scale atmospheric circulation ...

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... Thus the region provides reference stratotypes used in the compilation of the stratigraphic and Pleistocene palaeogeographic scheme for European Russia and a correlation scheme for events in Northern Eurasia. The relevance of the Lower Volga region to palaeogeographic studies is expressed in the large number of representative Quaternary sections, their completeness, the content of sediments of different genesis (both marine and subaerial), the richness of the palaeontological material, and the ready availability for study (Moskvitin, 1962;Goretskiy, 1966;Fedorov, 1978;Rychagov, 1997;Svitoch and Yanina, 1997;Lavrushin et al., 2014;Yanina, 2014;Van de Velde et al., 2020;Költringer et al., 2021;Költringer et al., 2022 and many others). ...
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... Quaternary sediments of considerable thickness cover the Northern Caspian lowland and crop out along the lower branch of the Volga River. These deposits represent important environmental archives and allow the study of climate variations in the region and their relationship with Northern Hemisphere glaciations, Volga River dynamics and Caspian Sea level oscillations (e.g., Grichuk, 1954;Rychagov, 1997;Lebedeva et al., 2018;Költringer et al., 2020Költringer et al., , 2021Taratunina et al., 2021;Makeev et al., 2021). Over the past century, considerable research has described and discussed the marine and fluvial sequences of the Middle to Late Quaternary sediment sections in the Lower Volga valley (Fedorov, 1957;Svitoch, 2014), with the aim of addressing the timing and extent of changes in Caspian Sea level (Zastrozhnov et al., 2020;Leroy et al., 2014;Tudryn et al., 2013). ...
... More recently the intercalated subaerial terrestrial deposits have also received attention and have been described as loess-palaeosol sequences Makeev et al., 2021;Költringer et al., 2020Költringer et al., , 2021. These aeolian deposits, made up of near-source reworked Volga alluvium, are widely distributed in the Northern Caspian lowland (Kurbanov et al., 2018a(Kurbanov et al., , 2018bKöltringer et al., 2022) and show signs of both pedogenic and cryogenic reworking (Yanina, 2012;Költringer et al., 2020Költringer et al., , 2021Lebedeva et al., 2018;Makeev et al., 2021;Rogov et al., 2020;Taratunina et al., 2021). ...
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... This MF type is the most common in loess deposits and has widely been used for estimating paleowind directions (e.g. Banerjee, 2002, Zhu et al., 2004;Zhang et al., 2014;Gao et al., 2021;Költringer et al., 2021). ...
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Loess sequences are widely distributed in semi-arid regions around the world, and are sometimes also located in coastal zones. The accumulations of coastal loess provide a valuable record of both climate and sea-level changes. Here we report sedimentological and high sampling resolution luminescence dating evidence for such changes from two loess sequences from the Shandong Peninsula and Miaodao Archipelago near the coast of Bohai Sea in northern China. Both the quartz optically stimulated lumines-cence (OSL) and K-feldspar post-infrared IRSL (pIRIR 290) signals show consistent and satisfactory luminescence characteristics up to~100 ka, while the K-feldspar pIRIR 290 ages provide age control up tõ 200 ka and are in stratigraphic order. With this fully independent age model, our results reveal that coastal loess accumulation is episodic with a high variability in apparent accumulation rates. After comparing with global and regional sea-level records, we find that the intervals with high accumulation rates coincide with global low sea-level stages, and that the loess sedimentary hiatuses indicated by nearly zero or very low accumulation rates at one site mainly correspond to global high sea-level stages, indicating the dominant role of global sea-level changes on coastal loess accumulation in the study area. We therefore conclude that regional marine regression mainly occurred during MIS 6, and MIS 5b to MIS 2, with extremely low regional sea levels possibly around 150 ka, 70e60 ka and 37e24 ka, while high sea-levels occurred during MIS 5ee5c and MIS 1. This study implies that coastal loess deposits with a good chronology could be used to constrain the timing of regional sea level change.
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We present new palaeomagnetic and rock magnetic results with a stratigraphic interpretation of the late Early–Middle Pleistocene deposits exposed on the left bank of the River Danube at Dolynske, southern Ukraine. A thick succession of water-lain facies is succeeded by reddish-brown clayey soils, topped by a high-resolution loess–palaeosol sequence. These constitute one of the most complete recently discovered palaeoclimate archives in the Lower Danube Basin. The suggested stratigraphy is based on the position of the Matuyama–Brunhes boundary, rock magnetic, palaeopedological and sedimentological proxies, and it is confidently correlated with other loess records in the region (Roksolany and Kurortne), as well as with the marine isotope stratigraphy. The magnetic susceptibility records and palaeosol characteristics at Dolynske show an outstanding pattern that is transitional between eastern and south-eastern European loess records. Our data confirm that the well-developed S4 soil unit in Ukraine, and S5 units in Romania, Bulgaria and Serbia, correlate with the warm MIS 11. Furthermore, we suggest the correlation of rubified S6 palaeosols in Romania and Bulgaria and the V-S7–V-S8 double palaeosol in Serbia with S6 in Ukraine, a strong Mediterranean-type palaeosol which corresponds to MIS 15. Our new results do not support the hypothesis of a large magnetic lock-in depth like that previously interpreted for the Danube loess, and they prove that the Matuyama–Brunhes boundary is located within the palaeosol unit corresponding to MIS 19. The proposed stratigraphic correlation scheme may serve as a potential basis for further regional and global Pleistocene climatic reconstructions.