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In this study, we analysed a ~54‐m sediment core consisting of Quaternary sediments overlying the Neoproterozoic Muhos Formation in central western Finland, adjacent to the Gulf of Bothnia. The sediments recovered were logged, and their sedimentological characteristics defined. Two fine‐grained sediment units were subjected to biostratigraphical studies using pollen and diatom analyses. In addition, two sand‐rich units and a wooden stick were dated by the optically stimulated luminescence (OSL) and 14C‐AMS methods. The core sediments were divided into six units, where several diamicton, sand and gravel, and silt‐and‐clay‐dominated beds were studied. The results indicate that the sediment succession of the core beneath the Holocene Litorina Sea and the Ancylus Lake sediments of the Baltic Basin were deposited in glacial and lacustrine environments that existed in the Oulu River valley during the time period between the Saalian glaciation (MIS 6) and the Holocene. The stratigraphical evidence, supported by the OSL ages, suggests that the Scandinavian Ice Sheet (SIS) entered the Muhos area during the Saalian glaciation, and at least during three separate time intervals in the Weichselian stage. Stratigraphically controlled and age‐bracketed evidence shows that the first Weichselian SIS advance extended further south in the eastern part of Fennoscandia than previously estimated, and that this ice growth phase occurred during the Early Weichselian Herning Stadial (MIS 5d). The subsequent ice growth phases occurred during the Middle (MIS 4) and Late (MIS 2) Weichselian substages. The lacustrine and littoral sediments of the Muhos core were correlated with the late Eemian interglacial (MIS 5e) and two Weichselian interstadials (MIS 5c and MIS 3). [ABSTRACT FROM AUTHOR]

Because global sea level during the last interglacial (LIG; 130-115 ka) was higher than today, the LIG is a useful analogue for improving predictions of future sea level rise. Here, we synthesize sea level proxies for the LIG in the glaciated Northern Hemisphere for inclusion in the World Atlas of Last Interglacial Shorelines (WALIS) database. We describe 82 sites from Russia, northern Europe, Greenland and North America from a variety of settings, including boreholes, riverbank exposures and along coastal cliffs. Marine sediments at these sites were constrained to the LIG using a variety of radiometric methods (radiocarbon, U-Series dating, K-Ar dating), non-radiometric methods (amino acid dating, luminescence methods, and electron spin resonance, tephrochronology) as well as various stratigraphic and palaeoenvironmental approaches. As the areas in this database were covered by ice sheets from the penultimate glaciation and were affected by glacial isostatic adjustment (GIA), most of the proxies show that sea level was much higher than present during the LIG. Many of the sites show evidence of regression due sea level fall due to GIA uplift, and some also show fluctuations that may reflect regrowth of continental ice or increased influence of the global sea level signal. The database is available at https://doi.org/10.5281/zenodo.5602212 (Dalton et al., 2021). [ABSTRACT FROM AUTHOR]

Deglaciation patterns of the Scandinavian Ice Sheet in the Salpausselkä zone, southern Finland were studied. Digital elevation models (DEM/LiDAR‐imageries) were used to map and categorize glacifluvial formations of the study area, and evidence for ice re‐advance and retreat phases and their extent across the Younger Dryas Salpausselkä zone was collected. The results suggest that the Finnish Lake District Ice Lobe, located in SE Finland, retreated a minimum of 60 km north of the proximal side of the present First Salpausselkä ridge prior to the Younger Dryas, most probably during the Allerød interstadial (c. 13 900–12 700 years ago). This retreat phase was followed by a re‐advance after which the First Salpausselkä was formed (maximum age 13 300±900 years ago) in front of the Finnish Lake District Ice Lobe's ice margin. Subsequently, ice retreated further north and the Second Salpausselkä in front of the Finnish Lake District Ice Lobe margin was formed, according to OSL‐age determinations between 11 500 and 12 000 years ago. Previous research indicates that a similar retreat and re‐advance event to that of the Finnish Lake District Ice Lobe did not take place in the area covered by the Baltic Sea Ice Lobe to the southwest. Overall, the results suggest that the ice retreat of the Finnish Lake District Ice Lobe was of the same magnitude as the contemporary Allerød interstadial ice retreat event along the western flank of the Scandinavian Ice Sheet in Norway and minor ice‐sheet oscillations in central Sweden. [ABSTRACT FROM AUTHOR]

Southwestern Barents Sea sediments contain important information on Lateglacial and Holocene environmental development of the area, i.e. sediment provenance characteristics related to ice‐flow patterns and ice drifting from different regional sectors. In this study, we present investigations of clay, heavy minerals, and ice‐rafted debris from three sediment cores obtained from the SW Barents Sea. The sediments studied are subglacial/glaciomarine to marine in origin. The core sequences were divided into three lithostratigraphical units. The lowest, Unit 3, consists of laminated glaciomarine sediments related to regional deglaciation. The overlying Unit 2 is a diamicton, dominated by mud and oversized clasts. Unit 2 reflects a more ice‐proximal glaciomarine sedimentary environment or even a subglacial depositional environment; its deposition may indicate a glacial re‐advance or stillstand during an overall retreat. The uppermost Unit 1 consists of Holocene marine sediments and current‐reworked sedimentary material with a relatively high carbonate content. A significant proportion of the sedimentary material could be derived from Svalbard and transported by sea ice or icebergs to the Barents Sea during the late deglacial phase. The Fennoscandian sources and local Mesozoic strata from the bottom of the Barents Sea are the likely provenances of sediments deposited during the deglacial and ice re‐advance phases. Bottom currents and sea‐ice transport were the main mechanisms influencing sedimentation during the Holocene. Our results indicate that the provenance areas can be reliably related to certain ice‐flow sectors and transport mechanisms in the deglaciated Barents Sea. [ABSTRACT FROM AUTHOR]

Abstract: We determined in situ cosmogenic 10Be ages for nine boulders sampled on the Salpausselkä I (Ss I) Moraine. Previous dating of this moraine indicated that it formed during the Younger Dryas Stadial along the southern margin of the Scandinavian Ice Sheet in southern Finland. Our new exposure ages range from 10.9±1.0 to 13.5±1.2 10Be ka, with an error-weighted mean age of 12.4±0.7 10Be ka. Our results confirm four previous 10Be ages obtained 40km northeast of our sample location. The combined data ) indicate that retreat from the Ss I Moraine occurred at 12.5±0.7 10Be ka, in excellent agreement with an age of 12.1ka for retreat from the Ss I Moraine based on varve chronologies. These results identify the Ss I Moraine as among the best-dated margins associated with Late Quaternary ice sheets. [Copyright &y& Elsevier]