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Wind-abraded cobbles (ventifacts) and aeolian sand are known from the sandy-gravelly coastal areas of south-western Sweden, especially in association with raised deltas. Ventifacts are recorded on at least two different stratigraphic levels, at some sites atop glaciofluvial sediment, at other sites atop littoral deposits, and in some places at both levels, while aeolian sand usually forms a surficial cover. The formation of ventifacts has usually been coupled to abrasion due to katabatic winds from the retreating ice sheet or with periglacial climate during the Younger Dryas stadial (12.8–11.7 ka). To determine the timing of these deflation events, we have applied a combination of dating methods to ventifacts and associated sediments on top of an ice-contact delta at Veinge, south-western Sweden. Quartz and feldspar luminescence dating as well as portable luminescence profiling has been used for littoral and aeolian sediments over- and underlying deflation surfaces, while rock surface luminescence burial dating and paired 14C–10Be cosmogenic nuclide dating were conducted on ventifacts. The results show that a first deflation event occurred c. 16.5 ka, just after deglaciation and prior to a regional transgression that peaked around 15.7 ka. At 12.4–11.4 ka, during the Younger Dryas stadial, a new set of ventifacts formed on the surface of the exposed littoral sands and gravels. Some wind abrasion also occurred in the early Holocene, but at c. 8.5 ka the surface was covered by aeolian sand, up to 2.5 m thick. The combination of different dating methods have allowed us to draw more informed conclusions on the timing and duration of these wind abrasion/transport events than would have been possible from the use of only single-method dating. It has also made it possible to infer some environmental conditions during deposition. For example, both glaciofluvial and littoral deposits show evidence of incomplete bleaching of the luminescence signal. T

Recent suggestions propose that the glacial landscape in southern Sweden is primarily a relict from the Saalian glaciation (>130 ka). The arguments for this standpoint are the assertion that the majority of glaciofluvial deposits in this region are till-covered, and that wind-abraded clasts are observed at the contact between glaciofluvial sediments and till at numerous locations. Furthermore, it has been posited that this wind abrasion occurred during periglacial conditions during the Early Weichselian, preceding the Last Glacial Maximum (LGM). If this hypothesis holds true, it would necessitate a significant shift in our understanding of the Quaternary geological history for this region. To test this claim, we conducted an extensive examination of the purported stratigraphic conditions within 54 gravel pits situated south of the Middle Swedish End Moraine Zone (MSEMZ). The presence of a covering till bed on top of glaciofluvial sediments could only be confirmed in 22% of the gravel pits, and these sites were almost exclusively associated with ice-margin standstills/oscillations during the Late Weichselian deglaciation. In all other gravel pits where covering till could not be verified, ventifacts occur in several stratigraphic positions: at the contact between glaciofluvial and overlying littoral sediment, redeposited ventifacts within littoral sediment, and ventifacts at the contact between glaciofluvial or littoral sediments and overlying aeolian sediment. We conducted an extensive luminescence dating program (comprising 74 samples) in 22 of the gravel pits to determine the age of the ventification by dating underlying and overlying sediments. We conclude that wind abrasion across southern Sweden was not a single simultaneous event but rather a time-transgressive or recurrent process. It occurred in close conjunction with local deglaciation in some instances, while in others, it transpired later, extending into the Early Holocene. Notably, none of the enco

Wind-abraded cobbles (ventifacts) and aeolian sand are known from the sandy-gravelly coastal areas of south-western Sweden, especially in association with raised deltas. Ventifacts are recorded on at least two different stratigraphic levels, on top of glaciofluvial sediment and/or on top of littoral deposits, while aeolian sand usually forms a surficial cover. The formation of ventifacts has usually been coupled to abrasion due to katabatic winds from the retreating ice sheet or with periglacial climate during the Younger Dryas stadial (12.8-11.6 ka). However, there are very few absolute ages, and the timing of wind deflation has recently been challenged and proposed to be much older (110-70 ka). To determine the timing of these deflation events, we have applied a combination of dating methods to ventifacts and associated sediments on top of an ice-contact delta at Veinge, south-western Sweden. Quartz and feldspar luminescence dating as well as portable luminescence profiling has been used for the over- and underlying sediments, while rock surface luminescence burial dating and paired 14C10Be cosmogenic nuclide dating were done on ventifacts. The results show that a first deflation event occurred c. 16.5 ka, just after deglaciation and prior to a regional transgression that peaked around 15.7 ka. At 12.4-11.4 ka, during and just after the Younger Dryas stadial, a new set of ventifacts formed on the surface of the exposed littoral sands and gravels. Some wind abrasion also occurred in the early Holocene, but at c. 8.5 ka the surface was covered by aeolian sand, up to 2.5 m thick. The combination of dating methods allowed us to extract more information about the timing and duration of these wind abrasion/transport events than we would have if only a single method had been used, and it is also possible to infer some environmental conditions. For example, both glaciofluvial and littoral deposits show evidence of incomplete bleaching of the luminescence signal. This sugg

The Siljan region hosts Europe´s largest impact structure. The high-relief landscape, with a central granite dome bordered by lake basins, contains an array of glacial and shore-level landforms. We investigated its deglaciation history by mapping and analysing landforms on high resolution LiDAR-based Digital Surface Models coupled with well-dated sediment successions from peat and lake sediment cores. The granite dome and bordering areas are characterized by streamlined terrain and ribbed moraine with a streamlined overprint. These suggest an ice-flow direction from NNW with wet-based thermal conditions prior to deglaciation. During its retreat, the ice sheet was split into thinner plateau ice and thicker basin ice. Sets of low-gradient glaciofluvial erosion channels suggest intense ice-lateral meltwater drainage across gradually ice-freed slopes, while 'down-the-slope' erosion channels and eskers show meltwater drainage from stagnated plateau ice. Thick basin ice receded with a subaqueous margin across the deep Siljan–Orsasjön Basin c. 10,700–10,500 cal. BP. During ice recession the ingression of the Baltic Ancylus Lake led to diachronous formation of highest shoreline marks, from 207 m in the south to 220 m a.s.l. in the north. Differential uplift resulted in shallowing of the water body, which led to the isolation of the Siljan¬–Orsasjön Basin from the Baltic Basin at c. 9800 cal. BP. The post-isolation water body – the ‘Ancient Lake Siljan' – was drained through the ancient Åkerö Channel with a water level at 168–169 m a.s.l. during c. 1000 years. A later rerouting of the outlet to the present course was initiated at c. 8800 cal. BP, which led to a lake-level lowering of 6–7 m to today’s level of Lake Siljan (162 m a.s.l.). This study shows the strength of an integrated methodological approach for deciphering the evolution of a complex landscape, combining highly resolved geomorphological analysis with well-dated sediment successions.

Recent suggestions propose that the glacial landscape of southern Sweden is a relict landscape from the Saalian glaciation (>130 ka) (Lagerbäck, 2018). The primary argument supporting this viewpoint is the claimed observation that the majority of glaciofluvial deposits in this region exhibits a covering till bed, often accompanied by wind-abraded clasts (ventifacts) at the contact between glaciofluvial sediment and till. It has been further posited that this wind abrasion event dates back to the Early Weichselian, preceding the last glaciation, and occurred during periglacial conditions of that period. If this were indeed the case, it would imply that generations of Quaternary geologists had overlooked or disregarded this relationship, necessitating a paradigm shift in our comprehension of the Quaternary geological history of the area.To assess the validity of these claims, we conducted a comprehensive evaluation of purported stratigraphic conditions within 54 gravel quarries south of the Middle Swedish End Moraine Zone (MSEMZ). The presence of a covering bed of what can be sedimentologically interpreted as a glacially deposited diamict  a till  above glaciofluvial sediments was confirmed in only 22% of the gravel pits. These occurrences were primarily linked to locations in close proximity to well-known positions associated with ice-margin standstills or oscillations during the Late Weichselian. In all other quarries, where the presence of covering till could not be confirmed, ventifacts were found in various stratigraphic positions. These positions were contingent upon deglacial and post-deglacial environmental conditions and included ventifacts at the contact between glaciofluvial and overlying littoral sediment, ventifacts redeposited within littoral sediment, and ventifacts at the contact between glaciofluvial or littoral sediment and overlying aeolian sediment.To ascertain the age of the ventifaction event(s), we conducted an extensive luminescence (OSL) dat

The extent of vegetation openness in past European landscapes is widely debated. In particular, the temperate forest biome has traditionally been defined as dense, closed-canopy forest; however, some argue that large herbivores maintained greater openness or even wood-pasture conditions. Here, we address this question for the Last Interglacial period (129,000–116,000 years ago), before Homo sapiens–linked megafauna declines and anthropogenic landscape transformation. We applied the vegetation reconstruction method REVEALS to 96 Last Interglacial pollen records. We found that light woodland and open vegetation represented, on average, more than 50% cover during this period. The degree of openness was highly variable and only partially linked to climatic factors, indicating the importance of natural disturbance regimes. Our results show that the temperate forest biome was historically heterogeneous rather than uniformly dense, which is consistent with the dependency of much of contemporary European biodiversity on open vegetation and light woodland.

The Siljan region hosts Europe's largest impact structure. The high-relief landscape, with a central granite dome bordered by lake basins, contains an array of glacial and shore-level landforms. We investigated its deglaciation history by mapping and analysing landforms on high resolution LiDAR (light detection and ranging)-based digital surface models coupled with well-dated sediment successions from peat and lake sediment cores. The granite dome and bordering areas are characterized by streamlined terrain and ribbed moraine with a streamlined overprint. These suggest an ice-flow direction from north-northwest (NNW) with wet-based thermal conditions prior to deglaciation. During its retreat, the ice sheet was split into thinner plateau ice and thicker basin ice. Sets of low-gradient glaciofluvial erosion channels suggest intense ice-lateral meltwater drainage across gradually ice-freed slopes, while ‘down-the-slope’ erosion channels and eskers show meltwater drainage from stagnated plateau ice. Thick basin ice receded with a subaqueous margin across the deep Siljan–Orsasjön Basin c. 10,700–10,500 cal. bp. During ice recession the ingression of the Baltic Ancylus Lake led to diachronous formation of highest shoreline marks, from ~207 m in the south to ~220 m above sea level (a.s.l.) in the north. Differential uplift resulted in shallowing of the water body, which led to the isolation of the Siljan–Orsasjön Basin from the Baltic Basin at c. 9800 cal. bp. The post-isolation water body – the ‘Ancient Lake Siljan’ – was drained through the ancient Åkerö Channel with a water level at 168–169 m a.s.l. during c. 1000 years. A later rerouting of the outlet to the present course was initiated at c. 8800 cal. bp, which led to a lake-level lowering of 6–7 m to today's level of Lake Siljan (~162 m a.s.l.). This study shows the strength of an integrated methodological approach for deciphering the evolution of a complex landscape, combining highly resolved geomorphological analys

Because global sea level during the last interglacial (LIG; 130–115 ka) was higher than today, the LIG is a useful approximate 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, uranium–thorium, potassium–argon), non-radiometric methods (amino acid dating, luminescence methods, electron spin resonance, tephrochronology) as well as various stratigraphic and palaeo-environmental approaches. In general, the sites reported in this paper do not offer constraint on the global LIG highstand, but rather evidence of glacial isostatic adjustment (GIA)-influenced sea-level positions following the Marine Isotope Stage 6 glaciation (MIS 6; 191–130 ka). Most of the proxies suggest that sea level was much higher during the LIG than at the present time. Moreover, many of the sites show evidence of regression due to sea-level fall (owing to glacial isostatic uplift), and some also show fluctuations that may reflect regrowth of continental ice or increased influence of the global sea-level signal. In addition to documenting LIG sea-level sites in a large swath of the Northern Hemisphere, this compilation is highly relevant for reconstructing the size of MIS 6 ice sheets through GIA modelling. The database is available at https://doi.org/10.5281/zenodo.5602212 (Dalton et al., 2021).