Search

Satellite-based maps of glacial landforms reveal that the mountain landscapes of northeast Eurasia contain over one million km2 of glaciated terrain. Previous work has speculated on the existence of large ice masses during the Last Glacial Maximum (LGM) and the preceding cold phases, but the lack of age constraints means that little is known about the timing of past glaciations across this vast region.With an aim to gain a better understanding of the glacial history of this region, we collected samples for cosmogenic 10Be exposure dating of boulder erratics and moraines in the mountains of eastern Siberia. Here, we present the first results from two sites, both within the Chersky Range: (1) Malyk Sen, which contains a succession of three end moraines in a foreland setting; and (2) Ust-Nera, which features boulder erratics and glacial bedrock pavement exposed in a previously glaciated valley. At Malyk Sen, the relative positions and corresponding ages of the three moraines indicate progressive contraction of maximum glacier extent since termination of the Marine Isotope Stage (MIS) 6, with the innermost moraine dated to the LGM. Our preliminary results from Ust-Nera suggest exposure ages from glacially-transported boulders and bedrock pavement that are significantly older than the LGM. Both sites indicate limited extents of mountain glaciation during the LGM in eastern Siberia. And while the glacial chronology of our study does not extend beyond MIS 6, mapping of the surrounding areas indicates that even more expansive glaciers existed further back in time.Our findings confirm the trend of successively smaller glacial extent maxima’s in continental Eurasia towards the LGM, with at least one ice advance during MIS 5-3 larger than the LGM advance. This trend could to be linked to extreme continental settings such as in Eurasia and westernmost America, as it contrasts with larger parts of the Northern Hemisphere glaciations where Late Pleistocene maxima were reached during LGM.

Loess deposits are widely spread all over Eastern Europe, extending as far south as the Sea of Azov and the northern Black Sea. For many decades these regions have been noted for series of key sections. However, despite prolonged investigations, a lack of absolute dating and detailed lithological data has left many unresolved problems in the correlation of the regional stratigraphic schemes. In this study, integrated studies were undertaken on the loess-paleosol sequence exposed on the northern coast of the Taman Peninsula, separating the Sea of Azov from the Black Sea. The exposure in the coastal scarp near Cape Pekla was sampled in detail for standard lithological and stratigraphic analyses, and for the first time, detailed data on the sediments lithology and petromagnetic properties were obtained, as well as the first optically stimulated luminescence age estimates. The data lead us to conclude that the formation of continental series exposed in the Pekla section started at the beginning of the Middle Pleistocene. There are five well pronounced buried soil complexes (PS 1–5) exposed in the sequence, covering sedimentation from the Middle Pleistocene to the present day. We attribute two lower paleosols (PS 4 and PS 5) to two main warm intervals of the Middle Pleistocene – MIS 9 and MIS 13, and the Kamenka interglacial paleosol, correlated with MIS 7 from other parts of the Azov loess area, is represented in the Pekla section by a sand layer formed at the time of the marine transgression dated to interval 220–280 ka (MIS 7). The upper soil horizons (PS1, PS2 and PS3) developed between 20 and 220 ka. The Pekla section contains a considerable proportion of sand fraction – presumably, due to active eolian processes that developed in immediate vicinities of sources of the material. The paleosol characteristics and the structure of loess horizons in the Pekla subaerial series differ considerably from the well described loess-paleosol series of the Northern Azov Sea coasts. In all probability, this region of the Taman Peninsula belongs to a specific province located south of the North Azov loess-soil province.

The variability and dynamics of the Asian monsoon (AM, hereafter indicates both of the summer and winter monsoons.) at orbital and millennial timescales has attracted wide interest. Chinese loess deposits, covering an area of ~500 × 103 km2 and with a thickness of several tens to more than three hundred meters, is an ideal continental archive to reconstruct AM variations during the Quaternary epoch. Over the past thirty years, since the earliest paper published in an international journal that linked the Asian monsoon and Chinese loess deposits, many studies have been undertaken focusing on this research topic. These results have greatly deepened our understanding of the variations of the AM climate and their driving mechanisms during the past ~2.6 Myr. In this paper, we emphasize recent progress on the AM variability and dynamics revealed by Chinese loess records; in particular, we discuss the reliability and precision of the timescale and the monsoon proxy indicators for the loess-paleosol sequences, which are two fundamental aspects for understanding AM behavior. We analyze what we know and discuss what we do not know about the AM. We refine the timescale for the typical loess-paleosol sequence in the central Chinese Loess Plateau (CLP), which can be used as a new timescale to study palaeoclimate and palaeoenvironmental changes in the monsoonal Asia. We conclude that low-latitude insolation changes induced by precession, and global ice volume, temperature at high-latitudes, as well as sea-level changes forced variations of the AM at orbital time scales. High-latitude cooling events and low-latitude hydroclimate process at millennial time scales, such as climate changes associated with Heinrich events and Dansgaard-Oeschger cycles in Northern Atlantic and Greenland, have also modulated AM variability. We suggest that high-latitude forcing of AM variations occurs through ocean and atmospheric circulation linkages, although the roles of atmospheric CO2, ocean and vegetation feedbacks need further investigation. In future study, high-resolution independent dating, novel proxy indices and transient numerical simulations are still basic tools to understand the loess deposition and AM variations that require considerably more work. Issues such as reliable spatial comparison and regional linkages of records (dependent on precise and accurate numerical chronologies), and quantitative reconstruction of the AM variations, should be given priority in the study the past climate change in Asia, and low-latitude hydroclimate process.

We present results for three sections with a representative loess record of the end of the Late Pleistocene from the south-east of Western Siberia. These sections are characterized by different structure and formed in different geomorphological position of Ob Loess Plateau and Cis-Salair plain. The age of deposits within MIS 1 - MIS 3 is determined by radiocarbon and OSL dating. Data on the quartz grain morphology confirmed that aeolian processes were the main factor in the accumulation of studied profiles, the influence of cryogenic weathering was also noted. Evidence of the MIS 2 warmings have been recorded in the northwestern Salair region (Ust’-Chem section), presented by two weakly developed Late Glacial paleosols formed 14.9–12.3 kyr ago. The distribution of magnetic susceptibility and grain size records in the Lozhok and Klyuchi sections reveals a period of relatively long term aridization with an increase in atmosphere dustiness in the lower part of the Eltsovka loess (MIS 2). The trend of increase in humidity with decrease in the atmosphere dynamics is observed during the second part of MIS 2. An event of activation of local aeolian processes with dune formation took place 47 kyr ago (the first half of the Karga interstadial; MIS 3) in the Klyuchi section. It is supposed that the geomorphological situation and the presence of nearby material available for local redeposition was a significant agent in the formation of the lower layer of Klyuchi and Ust-Chem sections. It was formed by combined deposition of silt material from the atmosphere flow and by the local aeolian transportation of sand. Permafrost-solifluction event was established in the northeastern part of the Ob Loess Plateau at about 23 ka.

This article studies the discoid Didacna sp. shell beads discovered at Kaylu, a Middle Holocene burial site located in Southern Turkmenistan. Microscopic, morphometric, spectrometric, and SEM analyses were carried out on the material to identify how the beads were manufactured and used. New radiocarbon dating and bioanthropological data to age and sex the two skeletons discovered in the burials are provided. A regional synthesis shows that personal ornaments from the Caspian region were diversified through time and that a stylistic shift between the last foragers and the first farmers occurred. We also observed strong correspondences between the personal ornaments documented in the northern, eastern, and western Caspian Sea during the Neolithic, with no evidence of similar symbolic production in Northern Iran. We propose that a northern route may have allowed the diffusion of common ornamental traditions in the Caspian region to the exclusion of the southern Caspian. Alternatively, discontinuities in material culture diffusion in coastal areas could be evidence of maritime voyaging. Seafaring may have granted the fast and spatially erratic diffusion of specific bead types, people, information, knowledge, and symbols from both sides of the Caspian Sea, by long maritime voyages or by leapfrog diffusion during the Neolithic.

В статье представлены данные, полученные на новом этапе исследований верхнепалеолитической стоянки Актас, первые работы на которой были проведены в 1982-1983 гг. Памятник расположен в Северном Казахстане, где палеолитические объекты очень редки. В работе приводятся материалы по стратиграфии, палеонтологии, археологии и хронологии стоянки. На памятнике выделены шесть литологических слоев, два из которых (3 и 4) содержат многочисленные фаунистические остатки. Хронология объекта построена на серии ОСЛ-дат. Установлено, что накопление слоя 2 происходило в интервале ~20-12 тыс. л.н., слои 3 и 4 формировались ~50-30 тыс. л.н. На памятнике найдено изделие из камня — скребло из «импортного» кремня. Основу ископаемого фаунистического комплекса составляют копытные — плейстоценовая лошадь Equus ferus, шерстистый носорог Coelodonta antiquitatis и горный баран Ovis ammon. Часть костных остатков несет следы преднамеренной фрагментации и разделки с помощью каменных орудий. С учетом этого, а также особенностей тафоценоза (видовой состав, отсутствие следов деятельности хищников и др.), расположения и стратиграфии стоянки сделан вывод о том, что данное скопление палеофауны могло сформироваться только в результате антропогенной деятельности. Единичные свидетельства пребывания человека позволяют рассматривать Актас только как «эфемерную» стоянку, фиксирующую заселение данной территории в позднеплейстоценовое время, без каких-либо культурных определений. Материалы памятника соответствуют стоянкам типа kill-site — местам разделки и потребления охотничьей добычи. На данный момент это единственная стоянка подобного типа в исследуемом регионе. Малочисленность каменных артефактов не позволяет определить культурную принадлежность ее материалов. Однако возраст памятника свидетельствует о том, что северные районы Казахстана были заселены уже в начале МИС3, что соответствует начальным этапам верхнего палеолита.

We have analyzed the modern status of the chronostratigraphic differentiation of the loess–paleosoil series in southwestern Siberia and the results of luminescence dating of the reference section of the Altai low mountains near the settlement of Krasnogorskoe. A complete series of the Middle and the Late Pleistocene levels of paleosoil formation is distinguished. Six new dates were obtained for the section by optically stimulated luminescence (OSL) and infrared stimulated luminescence (IRSL), and two samples were measured simultaneously, using quartz and feldspar, to control the light exposure and the reliability of the absolute age determined. The results obtained indicate the formation of the lower Berdsk paleosoil during the last interglacial period, which corresponds to Marine isotopic stage (MIS) 5e, and two dates of the underlying loess (127 and 149 ka BP) confirm that the age of this strata correlates with MIS 6. The age of the overlying Iskitimsk pedocomplex and of the horizon of Yeltsovsk loess is also substantiated by four OSL dates (48–39 and 39–25 ka BP). The final chronology confirms the previously elaborated chronostratigraphic scheme of the loess–paleosoil series in southwestern Siberia, which is based on a detailed morphological characteristic of paleosoils.

Srednaya Akhtuba outcrop provides a detailed record of the Late Pleistocene continental and marine deposits and paleosols from MIS5 to MIS1. The MIS5 chronozone is presented by a continuous pedosedimentary sequence with three well-developed paleosols. The paper is based on the study of depositional environment and pedostratigraphy, with OSL chronological framework and precise altitude references. Field data are supported by chemical analyses, micromorphology, and clay mineralogy. A detailed study of MIS5 paleosols was first conducted for the Lower Volga area. Pedosedimentary sequence at that time developed on the river terrace in a backswamp and/or wetland influenced by extremely slow-moving stream after long seasonal floods. Thin loess layers were deposited during the brief episodes of low flood activity, while fluvial heavy loams – at the time of more intensive flooding. Mollic Gleysols and Fluvic Chernozems have been formed in the arid or semi-arid climate with seasonal freezing under productive wet meadows. Changes in the depositional environment resulted in the formation of welded paleosols, marked by textural difference, cryogenic levels, and accretionary humus horizons. Despite the complicated depositional pattern and the influence of seasonal floods, the MIS5 pedosedimentary sequence may serve as a good stratigraphic marker for the onset of Late Pleistocene allowing correlation with loess-paleosol sequences of the whole Ponto-Caspian region and linking it with the global stratigraphic schemes.

Permafrost is considered to be one of the important sources of additional water for the vast Late Quaternary Caspian Sea transgressions. The insufficiency of proxy evidence on landscape and climate dynamics during the long Atelian regression (MIS 4 – MIS 3) complicates the analysis of changes in the Caspian water balance. Traces of Late Pleistocene cryogenesis structures were catalogued in the alluvial and loess-soil deposits of the Srednyaya Akhtuba reference section. Four stages of permafrost development were described for the first time in the Lower Volga region. Under conditions of seasonal and longer-term freezing in the Late Pleistocene, cryogenic transformation of the deposits took place; this determined the composition, structure and properties of the loess-paleosol complex at the site. Cryolithological, micromorphological analyzes and particle size distribution of mineral matter were carried out for each horizon, and traces of cryogenic processes were described in order to evaluate the regional paleoclimatic conditions that prevailed during their formation. Optically stimulated luminescence dating was used to establish a chronological framework for the main phases of the development of cryogenic modification in the Lower Volga region. The fourth stage of formation involved deep cracking of the substrate, which occurred during freezing in MIS 4, coincident with the Atelian regression of the Caspian Sea. The third stage is expressed as large wedge-shaped structures (pseudomorphs) on the border of loess and alluvial packages, with their formation known to be associated with the degradation of ice wedges. During the second and first stages of freezing, plastic deformation of deposits occurred.

Due to the high preservation of the loess series and the availability of coastal outcrop sections loess cover of Western Ciscaucasia has ample opportunities for spatial paleogeographical reconstructions for the Middle and Late Pleistocene. Currently, the level of knowledge on the structure and composition of the loess-paleosol sequences of Western Ciscaucasia remains unequal. The Azov coast is studied in more detail in comparison with the inner part of the region. The structure and composition of the loess-paleosol sequences of different parts of Western Ciscaucasia (the Sea of Azov coast and western macroslope of the Stavropol Upland) for the Middle and Late Pleistocene are compared. Comparison of the key sections are based on litho- and pedostratigraphy, magnetic susceptibility, grain size, elemental and mineral composition, and luminescence dating. Recent results of luminescence dating allowed correcting the structure of the Mezin pedocomplex (S1). It was found out that this pedocomplex includes three phases of soil formation (S1SS1, S1SS2, S1SS3), which approximately correspond to the warm stages of marine isotope stage 5 (MIS 5) – 5a, 5c, 5e. In all sections, a clear trend towards an increase in the accumulation rates over the last three climatic macrocycles is observed. The last interglacial-glacial macrocycle (MISs 2–5) is characterized by the most significant increase in average accumulation rates, which were ∼1.8 times higher compared to MISs 6–7 and ∼2.3 times higher than during the MISs 8–9. A likely reason for the regional increase in the average dust accumulation rate was the directional increase in climate aridity. The patterns of the spatial distribution of the loess thickness and material composition indicate that the main source of aeolian dust is situated in the east. We suppose that the main sources of dust are sand masses of the alluvial plains of Lover Volga, Terek, Kuma and Kura rivers in the Caspian lowland. The Lower Don sandy province is reconstructed to be a secondary source. Dust is blown from the sandy terraces of the Don, and in the past - from the Don deltas, during the period when the Sea of Azov dried up.

New results of Optically-Stimulated Luminescence (OSL) dating that make it possible to clarify the age of the Chibitskii glaciation in the Altai Mountains are reported. Three dates were obtained from the upper part of the lacustrine–glacial Baratal sands, logically distributed within the chronological interval from 21.0 to 14.4 ka. Fluvioglacial sands from the drift moraines of the last Kuekhtanar glacier, three OSL-ages of which are in the interval of 30–24 ka, correlate with the Baratal limnoglacial. The origin of Sukor Lake is associated with the Sukor landslide, which dammed the Chuya River valley. According to eight OSL dates, which have been obtained for the Sukor sands, the dammed Sukor Lake existed in the interval from 16 to 11 ka. New OSL dates provide a more reliable reconstruction of the Chibit glaciation age and the position of the corresponding sediments in the Quaternary stratigraphic chart of the Altai–Sayan Mountain Country, as corresponding to the Last Glacial Maximum (LGM), i.e., the fourth stage of the Upper Neopleistocene of the Russian stratigraphic chart.

The article presents the results of a joint Russian-Tajik geoarchaeological expedition in the middle reaches of the Obi-Mazar River (Republic of Tajikistan). During 2021 fieldwork two Tajikistan Loess Palaeolithic sites were studied: Kuldara (14 pedocomplexes) and Obi-Mazar (7 pedocomplexes). A significant amount of palaeogeographic work was carried out at both sites including sampling for a wide range of geological analyses. At Kuldara, five excavation trenches were established and a small amount of artifacts from pedocomplexes 4 and 5 as well as a few items from PC’s 10 and 11 were collected. Lakhuti IV corresponding to PC 5 was found between the known sites of Obi-Mazar-6 and Lakhuti I. The excavation area was 6 m2 and 2.2 m deep. Archaeological material (662 specimens) was deposited at 8 levels, but can be regarded a single industry. The primary reduction is based on several simple flaking techniques — radial flaking from a single surface, citron and parallel flaking. Some cores were prepared on large and thick spalls; the ventral surface was used as a prepared flaking surface. “Citron flakes” were also found (~ 8 % of the total number of flakes). Not a single blade was discovered. The complex contains roughly equal proportions of scrapers on large spalls, notched-denticulate tools and unifaces. According to the available set of geological data for the Obi-Mazar Valley, PC 5 is dated to ca. 0.5 Ma. The Lahuti IV materials have parallels in the synchronous Early Palaeolithic industries of Tajikistan. A distinctive feature of this site is a very high concentration of artifacts and their occurrence in well-defined cultural horizons, which is recorded for the first time at Loessic Palaeolithic sites.

In 2021 a joint Russian-Azerbaijani geoarchaeological studies were carried out in Republic of Azerbaijan. The coastal area of the Mingechevir Reservoir was investigated, primarily the beaches of the south-western shore at the foots of the Bozdag and Garaja Ranges. A representative collection of stone artifacts (136 specimens) and Pleistocene faunal remains (35 specimens) were collected at the Garaja site. Among the cores, 80 % are simple nuclei of the parallel reduction strategy; few radial and citron cores were found. The main tool categories are choppers and large bifacially worked artifacts, pebble scrapers were also noted. The Garaja complex represents a homogenous lithic industry, well-correlated with the pan-Caucasus context of early Paleolithic complexes with bifacial tools and corresponds to the chronological period (the Bakunian period of the Caspian region) determined by geological and paleontological data. In addition to the Garaja site, another location of artifact concentration was discovered at 2 km eastwards of the main site. Here, 18 stone tools and a fragment of deer antler were found on a stretch of the beach about 100 m long; the artifact composition is similar to the Garaja collection. A test pit was established at Girmizi-Gaya in the outskirts of Ganja city. Four layers were distinguished in the trench; the two upper layers bore archaeological material. The total collection of artifacts (excavation and surface collection) amounted to more than 300 items. A fragment of a vessel rim found in layer 2 suggests attribution of the material to the late Neolithic or later period. Preliminary data make it possible to define this site as a short-term transit camp. In Nakhchivan Autonomous Republic, Gazma Cave, the only known Paleolithic site in this part of Azerbaijan, was studied. Here, the excavation trench was uncovered, the profile was cleaned up and a series of samples were taken for radiocarbon and OSL dating.

In 2021, the Lower Volga Paleolithic research team of the IAET SB RAS, participating in the Interdisciplinary Lower Volga Expedition organized by the IIMK RAS, the study of the Sukhaya Mechetka Middle Paleolithic site located in the northern outskirts ofVolgograd City was continued. The research was aimed at studying the chronostratigraphic position of the cultural layer and reconstructing the paleoclimate during the Neanderthal habitation period. In 2021, an additional geological section was established to the west of the buffer zone of the excavation area to study the stratigraphy of the right-side slope of the Sukhaya Mechetka gully. In 2021 the upper part of SM 14-18 (SМ East) stratigraphic sequence has been completely excavated (26 m thick). The new SM West stratigraphic sequence was established in 155 m westwards. Preliminary correlation of the layers and paleosol horizons in these two profiles was carried out. Samples for palynological, micromorphological, physicochemical and phytholithic analyses with the purpose to correlate the two sequences have been collected. Sediments were sampled for OSL dating. Studies of the buried paleosol are extremely important for understanding the dynamics of the climatic changes during the cultural layer accumulation at Sukhaya Mechetka. Pedogenetic levels that have been revealed in 2021 are comparable to the buried paleosol identified at the site earlier in depths, continuity and features of pedogenesis. Texturally graded buried paleosol described here for the first time for the SM West sequence expand our understanding of the soil spatial inhomogeneity, and, consequently, conditions of human habitation. Results of the ongoing field investigation will allow determining the cultural-chronological position of Sukhaya Mechetka in the context of the Eastern and Central European Middle Paleolithic complexes for the first time.

The article presents the results of interdisciplinary research at the Darvagchai- Zaliv-4 site. Long-term excavations at the site have revealed archaeological evidence confirming the presence of three complexes of artifacts belonging to different periods. A preliminary chronological framework of stone industries has been proposed based on malacofaunal analysis and paleomagnetic studies. For establishing the exact age, absolute dating of all geological horizons of the site was carried out using the OSL method, yielding thirteen dates which make it possible to determine the age of cultural horizons at the site. The collection of artifacts from the first complex is distinguished by Levallois splitting technique and typical Middle Paleolithic toolkit; the artifacts were located in the paleosoil horizon (layer 1b). Chronologically, this horizon belongs to the Riess-Wurm (Eem, Mikulin) interglacial in the interval of 125,000-110,000 BP (MIS 5e). Artifacts of another complex discovered in layer 3 (pebble-gravel deposits) belong to the Final Acheulean. Their age corresponds to the chronological range of 250,000-220,000 BP (MIS 7). The collection of stone objects from layer 5 (sea pebbles and sands) belongs to the Late Acheulean and testifies to the earliest appearance of ancient humans in that territory in 370,000-330,000 BP (MIS 11-10).

During the late Quaternary, dramatic changes in relative sea level (~170 m) are known to have occurred in the Caspian Sea. However, all previous attempts at resolving the uncertainty associated with the timing of these transgressive/regressive events, primarily using radiocarbon, have produced inconclusive or controversial results. Here we present the first reliable chronology for the largest known transgression (Early Khvalynian). This was derived using optically stimulated luminescence (OSL) analysis of sand-sized quartz, with support from infrared stimulated luminescence (IRSL) from K-rich feldspar grains, all extracted from 16 sediment samples collected along the Lower Volga River. These samples were taken from loessic sediments, marine clays (known as Chocolate Clays) and the overlying modern soils exposed at three sections (Srednyaya Akhtuba, Raygorod, Leninsk) ~200 km upstream of the present-day estuary. The differential bleaching rates of the quartz OSL and feldspar IRSL signals were used to evaluate the degree of resetting of quartz (and feldspar) signals; it was possible to conclude that all signals, and particularly quartz OSL, were sufficiently reset at deposition to allow accurate age estimation. Our results show unambiguously that the Early Khvalynian marine Chocolate Clays present at all three sections were deposited post-LGM, between ~17 and ~13.1 ka ago. These age estimates are further constrained by those from the overlying Kastanozem soils (9.6–0.7 ka) and underlying loess-soil series (32–19 ka), confirming a young (17–13 ka) age of the transgressive stage of the Early Khvalynian. Relative sea level during this period must have been well above the sampling altitudes of 11.7 m a.s.l. (Srednyaya Akhtuba), 11.3 m a.s.l. (Raygorod) and 4.7 m a.s.l. (Leninsk) to explain the absence of significant alluvial sand and to allow the deposition of the fine Chocolate Clays marker horizon.

Constraining the controls on the distribution of sediment at a continental scale is a critical step in understandinglong-term landscape and climate evolution. In particular, understanding of the role of rivers in wider sedimentrouting and impacts on aeolian loess formation on a continental scale remains limited. Extensive Quaternaryloess deposits are present on the East European Plain and in the Black Sea - Caspian Sea region and are associatedwith major rivers draining numerous surrounding cratonic and orogenic hinterland areas. Coupled with this,complex changes in local and global sea level have affected the extent and drainage of the Caspian Sea and theBlack Sea, and Quaternary glaciations have impinged on the northern margin of the East European Plain. Thissuggests that sediment routing and loess formation may show complex patterns and controls. Here, we applyU–Pb dating of detrital zircons from fluvial, marine and aeolian (dominantly loess) sedimentary records on theEast European Plain and in the Black Sea - Caspian Sea region. This shows a strong control of large rivers on thedistribution of sediments at a continental scale in the region, through long-distance transport of several 1000 km,sourced from continental and mountain glacier areas prior to marine or atmospheric reworking and trans-portation. Strong spatial variability in zircon U–Pb data from loess deposits on the East European Plain revealsmultiple diverse sources to the different individual loess sections, whereas no significant temporal variability inloess source is detected during the Late Pleistocene of the Lower Volga loess in South Russia. While the sedimentsupply from glacial areas via rivers plays an important role for the provenance of East European Plain loessdeposits, our data indicate that the stark spatial diversity in loess provenance on the East European Plain is oftendriven by the input of multiple local sources. Similar to the loess, marine sediments from different basins of theBlack Sea and the Caspian Sea also show significant spatial variability. This variability is controlled by the ba-thymetry of the seas, leading to sedimentary intermixing by sea currents within, but not between differentseparated sea basins. A direct comparison of marine and aeolian sediments at the same depositional site suggeststhat although loess and marine sediments are both dominantly sourced from river sediments containing fartravelled sedimentary material, local sources play a more important role in many loess deposits.

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. Grain surface features suggest that the material was glacially ground and fluvially transported prior to final aeolian deposition as loess. Secondary magnetic fabrics in the loess reveal pedogenic and cryogenic processes and a generally cold environment with brief shifts to warmer climate during late MIS 5 and MIS 3. Palaeowind reconstructions derived from preserved primary aeolian MF, indicate locally influenced westerly and north-westerly flow as part of a wider scale westerly wind pattern, similar to modern day winter conditions. We suggest that the climate of the last glacial in the Northern Caspian Lowland was cold and dry, with higher windspeeds and less variability during MIS 4 compared to MIS 3., Financial support of project BU235P18 (Junta de Castilla y León, Spain) and the European Regional Development Fund (ERD), project PID2019- 108753 GB-C21/AECI/10.13039/501100011033 and project PID2019-105796 GB-100/AECI/10.13039/501100011033 of the Agencia Estatal de Investigación. R. Kurbanov acknowledges the Russian Science Foundation project 19-77-10077. The Swedish Research Council is gratefully acknowledged for funding to T. Stevens for part of this project (2017e03888).

In the context of shifting the boundary of the Quaternary down to the level of 2.6 Ma and including the Gelasian Stage in the Quaternary System, the systematization of the original and published data on the geology and paleogeography of the Late Pliocene and Early Pleistocene of Eastern Europe has been carried out. It was established that, at the boundary of the Gauss and Matuyama paleomagnetic epochs, along with the general trend toward cooling and aridization, profound landscape and climate changes occurred and rhythmic fluctuations of the climate intensified. During the period from 2.6 to 1.8 Ma, corresponding to the Gelasian (pre-Tiglian and Tiglian of Western Europe or Paleopleistocene of Eastern Europe), there appeared subarctic landscapes. In the Eopleistocene (1.8–0.78 Ma) and the Early Neopleistocene (0.78–0.42 Ma), the climate became colder, and climatic zonality repeatedly underwent a complex restructuring, gradually approaching the modern one. Glacial deposits (layers of till) occurring in Eastern Europe date back to the Paleopleistocene. Evidence indicates that there were at least three independent glaciations in the Eopleistocene (1.8–0.78 Ma) and possibly four in the Early Neopleistocene. On the basis of studies of stratotypic sections, paragenetic links were established between sediments of different age within glacial and periglacial areas, and the paleogeographic events of the Early Pleistocene of Eastern Europe were correlated with those within the Western European region.

The Black Sea-Caspian Sea region is a vast and geomorphologically variable area where sea level changes, large rivers and their migration, and numerous interacting climate systems and aeolian regimes lead to a highly dynamic and complex situation of sediment supply and reworking. The area is blanketed by extensive loessic and sandy aeolian deposits, extending from northern Iran, through the Caucasus piedmont, Caspian lowland, and into the Crimea and East European Plain, as well as marine, fluvial and alluvial sediments. While loess deposits are especially extensive adjacent to major rivers such as the Volga, Don and Dnieper, the provenance, transport and nature of loess in this complex and highly dynamic environment remains poorly known.Both, the Black Sea and the Caspian Sea experienced several transgressive and regressive phases during the Pleistocene, with temporary connections occurring over the Manych passage and resulting in the formation of marine terraces over a wide area, which are dry at present. The sea levels of the Caspian and Black seas and long-range north to south sediment transport are heavily influenced by the great rivers draining the previously glaciated East European Plain, the Volga, Don and Dnieper. In addition, the Black Sea and Caspian Sea are surrounded by mountain ranges, with the Carpathians in the west, the North Anatolian Mountains south of the Black Sea, the Crimea-Caucasus orogen and the Alborz mountains extending from northeast of the Black Sea to south of the Caspian Sea, all of which may act as sediment source regions. Furthermore, more distal orogens lying to the east, such as the Ural, Altai, Pamir and Kopet-Dag, and their palaeo-drainage systems, also represent potential sediment source areas for the Caspian Sea basin. The Karakum desert lying to the east of the south Caspian combines the potential of being a sediment sink for material from these mountains, as well as a secondary source for the Caspian Sea and the large loess area in northern Iran.Here we apply U-Pb dating of detrital zircons to constrain the major sediment generating regions in this large area, transport pathways, and to further address the implications for sediment generation and cycling. In addition to loess, we aim to constrain the sediment transport pathways both for fluvial, marine and aeolian systems more generally, and to reconstruct the network of sediment routing in the Black Sea-Caspian Sea region. Our results reveal great spatial variability in zircon provenance and indicate the contribution of multiple source regions and transport pathways for most analysed samples and sites. Rivers have the strongest control on sediment erosion and distribution and are also in control of aeolian deposits, while not much sediment mixing seems to occur within the sea basins.

The late Quaternary development of the Lower Volga region of Russia is characterized by an alternating influence of marine and continental environments resulting from fluctuations in Caspian Sea level during the last glaciation. However, sediments deposited under continental conditions have received very little research attention compared to the under- and overlying marine deposits, such that even their origin is still in debate. Detailed magnetic mineralogical analyses presented here show clear similarities to loess. The results suggest that climate during the time of loess deposition, the Atelian regression (27–80 ka, MIS 4–3), was dry and cool, similar to the modern-day Northern Caspian lowland. The magnetic properties recorded in the loess-paleosol sequences of the Lower Volga also point to short episodes of potentially more humid and warmer climate during the late Atelian. The new findings in regard to the local Caspian climate and environmental evolution support decreased river discharge from the Russian Plain and Siberian Plain as the dominant factor causing the low Caspian sea level stand during the Atelian, although local-regional climate changes might have had an additional influence., The Swedish Research Council is gratefully acknowledged for funding to Thomas Stevens for part of this project (2017-03888). The work of Redzhep Kurbanov was supported by the Russian Science Foundation (grant 19-77-10077). Sofya Yarovaya was supported by the Russian Foundation for Basic Research (grant 18-00-00470). Balázs Bradák acknowledges the financial support of project BU235P18 (Junta de Castilla y Leon, Spain) and the European Regional Development Fund.

Mass-transport sediments are generally difficult to date directly by existing methods. Conventional luminescence dating of sand is unsuitable because the short transport distances provide little opportunity for bleaching. However, larger clasts are often exposed to sunlight for prolonged periods before becoming entrained in mass-movements, and these clasts have the potential to be used for rock-surface luminescence dating. Mass-transport is a major component of landscape change in mountain regions; in the Baksan valley, Caucasus Mountains, high uplift rates and high precipitation create a rapidly eroding landscape where preservation of sediments is poor. The area is particularly prone to destructive debris flows, because of the large quantity of detrital material in the catchments. The debris-flow and hillslope sediment the Baksan valley are used here to test the applicability of rock-surface burial dating to mass-transport sediment. We find that colluvial clasts show a high degree of bleaching and give reproducible ages, with a large colluvial deposit dated to the early–mid Holocene. The bleaching of debris flow clasts is more variable – we suppose due to the more complex transport history of the clasts, with opportunities for lengthy storage in moraines or colluvium. Overall, the results are encouraging, and suggest that rock-surface methods can provide a useful approach to mass-transport dating in mountainous regions. However, improved targeting of samples and measurement efficiency is desirable for widespread application.

In the latest decade, an active study has been conducted of the complexes of the final Pleistocene –Early Holocene in the territory of the Pamir-Alai within the framework of large-scale work of the Institute of Archaeology and Ethnography of the SB RAS in collaboration with local scientific centers. The latest research results allowed revising the cultural and chronological attribution of a number of key complexes and highlighting the Kulbulak culture and the Tutkaul line of development [Kolobova, 2014; Schneider, 2015]. Nevertheless, some of the objects known from the Soviet period have not yet been introduced into scientific circulation. In 2018, a field study was conducted of one of such objects – the Khoja-Gore site. During the work on the site, a representative collection of stone artifacts was collected, a geomorphological description of the site was made, and a series of samples were selected for OSL dating. Preliminary results allow us to change the existing cultural and chronological interpretation of the complex: at present, the industry of the Khoja-Gore sire is regarded as belonging to the Early Holocene period of the studied region. The closest technological analogies are highlighted in the Obishir-5 and Obishir-1 sites., В последнее десятилетие проводится активное изучение комплексов финального плейстоцена-раннего голоцена на территории Памиро-Алая в рамках масштабных работ Института археологии и этнографии СО РАН в содружестве с местными научными центрами. Последние результаты исследований позволили пересмотреть культурную и хронологическую атрибуцию ряда ключевых комплексов и выделить кульбулакскую культуру и туткаульскую линию развития [Колобова, 2014; Шнайдер, 2015]. Тем не менее, часть объектов известных с советского периода еще не введена в научный оборот. В 2018 г. проведено полевое изучение одного из таких объектов, стоянки Ходжа-Гор. В ходе работ на памятнике была собрана представительная коллекция каменных артефактов, проведено геоморфологическое описание стоянки и отобрана серия образцов для ОСЛ-датирования. Предварительные результаты позволяют изменить существующую культурно-хронологическую интерпретацию комплекса: в настоящий момент индустрия памятника Ходжа-Гор рассматривается как относящаяся к периоду раннего голоцена исследуемого региона. Ближайшие технологические аналогии выделены в комплексах стоянок Обишир-5 и Обишир-1.

Knowledge about origin and transport of aeolian mineral dust in the past and modern times plays an important role in the understanding of climate. Atmospheric circulation patterns and dust dynamics can be revealed by tracing back the provenance of airborne material. The source of loess deposits in the Lower Volga region of Russia is not known, yet represents a key location for Eurasian climate history reconstruction. The problem is addressed using U-Pb dating of detrital zircons from the loess deposits and potential source sediments such as East European Plain, Crimea, Caucasus, Volga, Caspian Sea and Central Asian desert sediments. Identifying the actual source of Lower Volga loess will help to understand past dust transport pathways and climate evolution in the region and its implications for regional and global climate.

International audience

The Kurai Fault Zone (KFZ) is one of the most hazardous seismogenic structures in the Gorny Altai (Russia). The KFZ have generated five paleoearthquakes with Mw = 6.6–7.6 and ESI 2007 shaking intensities of VIII to XI. The ultimate event, presumably in the second half of the 18th century, was preceded by four paleoearthquakes approximately 1.3, 3.2, 5.8, and 6.3 ka ago. The morphology of fault scarps, trenching results, deformation features in Neogene sediments, as well as electric resistivity surveys, reveal reverse slip mechanisms. All earthquakes were sourced by south-dipping backthrusts with respect to the main north-dipping reverse and thrust faults along which the Kurai Range is stepping over the two basins. The backthrusting maintains the growth of forebergs in front of the Kurai Range. Narrow basins limited by reverse faults separate forebergs from the Chuya and Kurai basins. Joint interpretation of geological (including trenching) and geophysical (ERT and GPR) data reveals the resistivity structure of the area with seismogenic faults traceable to depths of 40–50 m. The KFZ model, with the reconstructed relationships between the intramontane basins and the flanking mountains, as well as the structural control of large earthquakes, makes good reference for other worldwide regions of current and past seismicity in compressional settings. Assessment of probable magnitudes and recurrence of earthquakes within the KFZ is of special importance in view of the future deployment of the gas pipeline from Russia to China.