Early Weichselian Age Research Articles

ESR/U-series dating of palaeontological remains from the Neanderthal site of Mutzig-Rain (Alsace, France)

The Middle Paleolithic site of Mutzig-Rain, discovered in 1992, has been studied through several pits (called M1 to M15) and excavation area since 2009, evidencing several localities and delivering more than 5000 lithic artifacts and 12,000 well preserved paleontological remains. The main excavation M2 sequence corresponds to a collapsed rock shelter, containing several levels of Middle Paleolithic occupation. The faunal assemblage of the main archaeological levels (l.7a to 7c) from this sequence includes woolly mammoth, reindeer, horse, bison and woolly rhinoceros, reflecting both cold climate and a steppe context for the whole sequence, while microfauna from the lower levels (l.7d and l.10) indicate the occasional presence of forests that could correspond to a cooler climate. In 1995, U-series analyses on bones from M8 were attempted but the obtained results did not follow the sample stratigraphic order. Later, an OSL dating study has placed the M2 archaeological sequence as coeval to the onset of the Weichselian glacial stage (MIS5d-5a), between 100 and 80 ka.The good preservation of the abundant faunal remains at Mutzig-Rain has allowed their use for ESR/U-series dating studies and the results obtained on Mutzig horse teeth are given in the present paper. A first set of analyses of teeth carried out from the M2 excavation provided ages around 106-96 ka for levels M2 l.7, in agreement with the OSL data, despite quite systematic evidence of U-leaching from the dental tissues and the consequent use of the Accelerating Uptake (AU) model for the age calculation. A second set of analyses on teeth from the M2 and M8 localities confirms this uranium leaching trend, placing the deposition of these levels ca 133 -122 ka.Taking the whole set of ESR/U-series ages, which are slightly older than the OSL dates, would suggest that the stratigraphic sequence was deposited between ca 130 ka (M8 l. 6 and M2 l.10) and ca 100 ka (M2 l.7), i.e. on a time range covering the Eemian Interglacial (MIS5e) and the subsequent Early Weichselian Glacial stage (MIS5d-5a). However, as the faunal record indicates a cool climate and an open steppe-like environment for the whole archaeological sequence, the ESR/U-series dating to the Eemian Interglacial in the Mutzig-Rain sequence seems unlikely. In order to check the quality of the paleodosimetric reconstruction of the ESR/U-series analyses, an additional isochron study was performed for the two levels for which several teeth were analyzed: M2 l.7 (n = 4) and M8 l.6 (n = 3). This isochron study validates the proposed reconstruction and confirms the Early Weichselian age of these two levels. These results confirm the chronology established previously with OSL and places Mutzig-Rain as a reference site for the understanding of the Neanderthal Middle Palaeolithic occupation in Eastern France.

Sediments of MIS 5e age suggested by new OSL dates from the Skilvika section, west Svalbard

The sediment succession at Skilvika, west Svalbard, represents one of the key stratigraphic records of the Late Quaternary palaeoenvironments and glaciation history of the Svalbard/Barents Sea area. A formation of raised marine sediments, interfingering with and capped by glacial deposits of local origin, have previously been assumed to be of an Early Weichselian age, likely marine isotope stage (MIS) 5c. Here we present a new series of optically stimulated luminescence (OSL) ages that suggest the events took place in MIS 5e. This advocates a revision of the correlation with other key stratigraphic sites on Svalbard.

New luminescence ages reveal Early to Middle Weichselian deposits in central Latvia

New optically stimulated luminescence (OSL) ages show that sandy deposits overlain by Late Weichselian subglacial till in central Latvia are of Early to Middle Weichselian age. The finer chronological resolution of unconsolidated sediment deposition in the Central Latvian Lowland (CLL) remains relatively unstudied, and here we provide a first characterisation of the deposits with respect to their age. Three OSL ages ranging between 84 ± 9 ka and 112 ± 11 ka suggest that the deposits studied in the CLL are of Early Weichselian age (MIS 5). We found no Middle Weichselian deposits in the CLL, and assume that any such younger sediments might have been eroded during the advance of the Zemgale Lobe in the Late Weichselian. One site, in the ice-marginal zone adjacent to the interlobate area, has nevertheless deposits dated to 44 ± 10 ka corresponding to the Middle Weichselian (MIS 3). Our results are compatible with existing ESR ages on three sets of Portlandia arctica shells from the central part of the lowland; the shells had been incorporated into glacial deposits during later glacial advances. Finally, our findings largely support ice-free conditions during the Early and Middle Weichselian in the middle and southern part of central Latvia.

Fluvial evolution of the Rhine during the last interglacial-glacial cycle in the southern North Sea basin: A review and look forward

This paper presents the current state of knowledge on the evolution and depositional history of the River Rhine in the southern part of the North Sea basin during the upper Middle and Late Pleistocene, and its response to climate change, sea-level oscillation and glacio-isostasy. The study focuses on the development of the Eemian interglacial lower-delta in the central Netherlands and its relation to records of climate and sea-level rise, and uses the Saalian and Weichselian pre- and postdating periods to place its development in context.The Rhine fluvial system fills the gradually subsiding North Sea basin, but its development has strongly been affected by the Saalian glaciation and its remaining topography. Ice-pushed ridges originating off the limit of maximum glaciation basically divided the central Netherlands into two sedimentary depocentres: a central depocentre within the former ice-limit, and a southern depocentre south of it.The sedimentary record of the central depocentre, including an incised-valley fill, shows a 20–40 m thick stacked sequence consisting of three units. The incised-valley fill consists of a Late Saalian to early Eemian age lower fluvial unit and a Weichselian age upper fluvial unit, both composed of coarse-grained channel deposits. Sandwiched in-between is a 5–15 m thick record composed of fine-grained fluvial and estuarine (tidal) floodbasin and shallow-marine deposits. It is of Eemian interglacial and Early Weichselian age, and comprises transgressive and highstand deposits that show the drowning of a fluvial system. Inland parts transformed from fluvial to deltaic and estuarine environments, and the most downstream parts transformed to a shallow-marine embayment. Preservation of these units occurred, despite considerable sea-level fall and climate-controlled erosion taking place in the last-glacial. Preservation potential was increased by the fact that the Rhine system avulsed away to the southern depocentre, halfway the Weichselian Pleniglacial. Consequently, the infill of the southern depocentre is of an entire different nature, and last-interglacial transgressive or highstand units are hardly preserved.Because of glaciation and resulting depocentre configuration, the Netherlands in NW Europe thus offers a very good opportunity to study the transgressive interglacial lower-deltaic records and falling-stage preservation thereof – both key elements for understanding sedimentary development over full 100-ky glacial-interglacial cycles of climate and base-level change.

Re‐dating the Pilgrimstad Interstadial with OSL: a warmer climate and a smaller ice sheet during the Swedish Middle Weichselian (MIS 3)?

Alexanderson, H., Johnsen, T. & Murray, A. S. 2009: Re‐dating the Pilgrimstad Interstadial with OSL: a warmer climate and a smaller ice sheet during the Swedish Middle Weichselian (MIS 3)? Boreas, 10.1111/j.1502‐3885.2009.00130.x. ISSN 0300‐9483.Pilgrimstad in central Sweden is an important locality for reconstructing environmental changes during the last glacial period (the Weichselian). Its central location has implications for the Scandinavian Ice Sheet as a whole. The site has been assigned an Early Weichselian age (marine isotope stage (MIS) 5 a/c; >74 ka), based on pollen stratigraphic correlations with type sections in continental Europe, but the few absolute dating attempts so far have given uncertain results. We re‐excavated the site and collected 10 samples for optically stimulated luminescence (OSL) dating from mineral‐ and organic‐rich sediments within the new Pilgrimstad section. Single aliquots of quartz were analysed using a post‐IR blue single aliquot regenerative‐dose (SAR) protocol. Dose recovery tests were satisfactory and OSL ages are internally consistent. All, except one from an underlying unit that is older, lie in the range 52–36 ka, which places the interstadial sediments in the Middle Weichselian (MIS 3); this is compatible with existing radiocarbon ages, including two measured with accelerator mass spectrometry (AMS). The mean of the OSL ages is 44±6 ka (n=9). The OSL ages cannot be assigned to the Early Weichselian for all reasonable adjustments to water content estimates and other parameters. The new ages suggest that climate was relatively mild and that the Scandinavian Ice Sheet was absent or restricted to the mountains for at least parts of MIS 3. These results are supported by other recent studies completed in Fennoscandia.

Late Pleistocene fossil find in Svalbard: the oldest remains of a polar bear (Ursus maritimus Phipps, 1744) ever discovered

During recent fieldwork in Svalbard, a well preserved subfossil left mandible of a polar bear (Ursus maritimus Phipps, 1774) was discovered. A 14C age determination shows that it is older than 45 Ky (kilo-years), and an age determination with infrared-stimulated luminescence—together with the stratigraphic position of the bone—suggests that it is of Eemian–Early Weichselian age: 130–110 Ky old. This makes the find the oldest remains of a polar bear ever discovered. Morphological analyses of the mandible suggest that it comes from a fully grown male that was similar in size to extant male polar bears. The comparative study of other available subfossil polar bear remains did not reveal any significant change in size of polar bears during the Late Quaternary.

Late Pleistocene arctic fox ( Alopex lagopus) from Crimea, Ukraine

The teeth and bone fragments of Alopex lagopus of early Weichselian age from Mousterian layers of grotto Prolom 2 in Crimea have been studied. The Crimean fossil arctic fox was found to be smaller than the late Weichselian subspecies, A. l. rossicus, from the East European Plain, but it seems to be similar in dimensions to the recent insular subspecies, A. l. spitzbergenensis. From the latter, the Crimean arctic fox differs in the relatively longer carnassial teeth and relatively wider m1. In the Late Pleistocene of Europe, a progressive increase in size of A. lagopus is observed, that makes it possible to recognize two subspecies, stratigraphically replacing one another. The arctic fox from Prolom 2 is presumably referable to the subspecies A. l. meridionalis, while the animals from another Crimean Upper Paleolithic site, Siuren 1, are referred to A. l. fossilis.

The ESR age of Portlandia arctica shells from glacial deposits of Central Latvia : an answer to a controversy on the age and genesis of their enclosing sediments

The occurrence of Portlandia arctica shells in glacigenic sediments of Central Latvia had created a controversy in many publications about (1) their age ranging from the Holsteinian to the Late Weichselian and (2) the genesis of their enclosing sediments: glacial, glaciomarine or marine. Our reinvestigation of the main object of controversy, the Lı̄čupe site, leads to a conclusion that the sedimentary package of diamictons, clays and sands containing Portlandia arctica shells and marine microfossils is a large glacial raft that had been transported and deposited by the Riga lobe during the Weichselian. The electron spin resonance (ESR) ages on five sets of Portlandia arctica shells from the Lı̄čupe and Daugmales Tomēni sites range from 86.0±6.8 to 105.0±9.2 ka BP. These ESR age determinations and the cool climate indicators of the associated microflora and microfauna suggest that their source sediments, probably in the Gulf of Riga, are marine clays of Early Weichselian age, probably correlative to the Brørup Interstadial. In Central Latvia Portlandia arctica shells and their enclosing clay occur resedimented or translocated in glacial deposits during Weichselian glacial advances.

Signature of the last shelf-centered glaciation at a key section in the Pechora basin, Arctic Russia

The Vastiansky Kon' is the largest exposure of Quaternary deposits in the Pechora lowland, northern Russia. Morphologically the site belongs to the so-called Markhida Moraine; a complex, east–west trending zone of ice-marginal landforms deposited by the Kara Sea Ice Sheet during the last glaciation. The site exhibits a succession of sediments more than 100 m thick that, according to previous studies, covers the interval from the end of the Elsterian to the beginning of the Holocene. Unfortunately both the strong glaciotectonic deformation of the sedimentary succession and few absolute dates have made the chronological interpretation of the section difficult. The present paper reviews previous studies of the site published in Russian, and presents the results of a reinvestigation focusing on the post-Eemian stratigraphy. A marine Eemian clay more than 8 m thick is overlain erosionally by 20 m of fluvial deposits of Late Eemain or Early Weichselian age. The fluvial succession is overlain by a till and a marine clay, which, according to one interpretation, may represent an Early or Middle Weichselian advance of the Kara Ice Sheet followed by a transgression. The clay shows a transition into 15 m of estuarine and fluvial sediments overlain by more than 12 m of tundra–floodplain deposits. The whole succession has been upthrusted glaciotectonically by the last ice advance, which deposited a more than 12 m thick till on top of the section. Based on a number of subtill radiocarbon age-estimates from the site, in the range 25–32 ka BP, the youngest ice advance is considered to be of late Weichselian age, although a Middle Weichselian age cannot be excluded. © 1998 John Wiley & Sons, Ltd.

The last ice sheet of the Kara Sea: Terrestrial constraints on its age

Abstract The ice dispersal features on the Siberian mainland unanimously indicate that the last ice domes were positioned on the Kara Sea shelf and adjacent coastal plains. The age of the last glacial maximum evokes much controversy. The problem may be solved by sorting out the available radiocarbon dates, both statistically and using geological common sense. Over 200 finite radiocarbon dates have been analysed. 77% of the entire population represent sediments overlying the topmost till, including dating the most reliable organics such as mammoth remains. The rest of the dates (23%) have been obtained from the underlying sediments, mostly on materials readily prone to redeposition and contamination such as driftwood and shells. The last culmination of the shelf ice sheet must have occurred beyond the range of the conventional radiocarbon method and after the last warm-water sea transgression correlative to the Eemian. The Early Weichselian age for the last Kara Sea ice sheet is also supported by the lack of proglacial lacustrine sediments with finite radiocarbon dates in periglacial West Siberia.

Late Quaternary glacial and environmental history of Kongs�ya, Svalbard

On western Kongsoya, Svalbard, three coarsening-upwards sequences of marine to littoral sediments, separated by tills, are recognised in sections at ca 50-92 m above present sea level. These sequences show major glaciations in the northern Barents Sea, resulting in substantial glacioisostatic downpressing of Kongsoya. Till fabrics indicate ice movements controlled by the local topography, while glaciotectonic deformations suggest that ice moved from an ice divide northeast of Kongsoya. independent of the local topography. The stratigraphical evidences show two pre-Holocene ice-free periods, when the climate was similar to or slightly warmer than at present. The age of these periods is not clear. It is suggested that the elder ice free interval is older than isotope stage 5e. The younger ice free interval could be of Eemian or Early Weichselian age. The uppermost succession of sublittoral-littoral sediments is of early Holocene age. It relates to the high (?100 m) postglacial marine limit, dated to approximately 10,000 bp.

Late Quaternary glacial and environmental history of Kongsøya, Svalbard

On western Kongsøya, Svalbard, three coarsening-upwards sequences of marine to littoral sediments, separated by tills, are recognised in sections at ca 50-92 m above present sea level. These sequences show major glaciations in the northern Barents Sea, resulting in substantial glacioisostatic downpressing of Kongsøya. Till fabrics indicate ice movements controlled by the local topography, while glaciotectonic deformations suggest that ice moved from an ice divide northeast of Kongsøya. independent of the local topography. The stratigraphical evidences show two pre-Holocene ice-free periods, when the climate was similar to or slightly warmer than at present. The age of these periods is not clear. It is suggested that the elder ice free interval is older than isotope stage 5e. The younger ice free interval could be of Eemian or Early Weichselian age. The uppermost succession of sublittoral-littoral sediments is of early Holocene age. It relates to the high (?100 m) postglacial marine limit, dated to approximately 10,000 bp.

The lower Jyllandselv succession: evidence for three Weichselian glacier advances over coastal Jameson Land, East Greenland

Detailed investigations of sediments exposed along river sections in the coastal part of Jameson Land have revealed a Saalian to Holocene glacial history. Eleven sedimentary units have been distinguished. most of which are found in superposition at one single large section. Four subglacially formed till beds are recognized; three of which are of Weichselian age. All the tills are considered to have been deposited at the base of fjord glaciers restricted to the Scoresby Sund basin. The tills are separated by marine, fluvial or deltaic sediments, and demonstrate changes in the depositional environnient considered to represent changes in relative sea level during the ice‐free periods. The fossil content. supported by a series of luminescence dates, suggest that most of the succession is of Eemian and Early Weichselian age. From the luminescence dates, a short duration of <10ka is suggested for the Early Weichselian glacial stades. Sedimentation during this period was partly controlled by glacio‐isostatic subsidence caused by net growth of the Greenland Ice Sheet. The Middle Weichselian is represented by a large hiatus. whereas the Late Weichselian is represented by a subglacial till.

The pre‐Holocene marine limit on Hopen, Svalbard

A pre‐Holocene marine level is found at 109 m a.s.1. on Hopen. Fragments of Mya truncata and Hiatella arctica occurring on a raised coastal spit at that altitude have been radiocarbon dated to >45,000 BP. The amino acid epimerization of these shells, a clearly mixed sample, correlates with samples from Kongsøya that are of Eemian or Early Weichselian age (alloisoleucine/isoleucine ratios, hydrolysed fraction, between 0.084 and 0.213). No direct evidence, such as striations or roche moutonées, of overriding glacier ice has been found, and no erratics were found above the pre‐Holocene marine limit. The existing Holocene shoreline displacement curve, with its upper limit at 60 m a.s.1., is supported by four new radiocarbon dates.

Quaternary geology of western and central North Greenland

The earliest Quaternary event represented is the Kap Bryant glacial stade of probable Saalian age, in which an ice sheet covered the area out to the shelf. In contrast, in the Late Weichselian Kap Fulford stade, the area was only partly glaciated, with outlet lobes from an ice sheet occupying the outer fjords. There is some evidence of an earlier (Early Weichselian?) slightly more extensive glaciation (Kap Sumner stade). In the early Holocene, the ice margin had retreated to the middle regions of the fjords and extensive glacial lakes were formed in intervening areas. The Late Holocene Steensby stade produced a readvanee of the ice sheet at the head of the fjords and the growth of local ice caps. Reworked marine fossils in glacial sediments define the Hall Land marine event of Eemian and/or Early Weichselian age. The Late Weichselian/Holocene marine event (Nyeboe Land event) is abundantly represented by deposits whose distribution shows that the limit of transgression varied over the area, with a maximum at about 125 m above sea level. Regression from this limit occurred during the Holocene, initially at a slow rate. The fossil biota are described from the marine sediments and from a small number of terrestrial occurrences.

Evidence of ice movement over southwest Norway indicating an ice dome over the coastal district of west Norway

Records of several directions of ice movements occur in southwestern Norway. The oldest movement (Phase A) was towards NW and may be of Early Weichselian age or older. The Phase B ice moved towards S-SE, Phase C again towards NW, Phase D towards SW, Phase E was a local movement towards S, and Phase F is the Younger Dryas glacial movement. The Phase B ice flow markers most likely reflect a regional glacial phase. The emphasis is placed on a discussion of the age and palaeoglaciological implications of Phase B. One possible correlation is that Phase B corresponds to the ‘Jæren Stadial’ till, underlying the 40,000–30,000 BP ‘Sandnes Interstadial Clay’, at Jæren. Phase B ice flow markers further match the fabric of a till of supposed Early to Middle Weichselian age, southwesternmost coast of Norway. This till is deposited from NNW. Phase B suggests an ice sheet either based on the continental shelf in the North Sea, or it suggests an ice dome over the coastal district of west Norway. In the former case, evidence of a North Sea based ice should be expected around and in the North Sea. In the latter case, which is considered being the most likely one, it may explain the problematic occurrence of the ‘Sandnes Interstadial Clay’ up to very high altitudes at Jæren. The only possible land-evidence of a North Sea centered ice-mass older than Late Weichselian maximum is found at Caithness, Scotland, which suggests a pre-40,000 ice sheet in the North Sea Basin (Sutherland, 1984; Sejrup et al., 1987). However, the lithology of the North Sea sediments does not seem to show any till-like deposit between Late Weichselian maximum and 130–200 ka (Sejrup et al., 1987). The consolidating-value of pre-Late Weichselian North Sea sediments does not exceed 4000 kN/m 2, while a P′ C-value of about 15,000 kN/m 2 should be expected if the ice thickness was about 1500 m. However, sediments will not be compressed unless: (1) they are unfrozen, and (2) the pore water can escape. Coastal ice domes may have occurred both at the onset and final stage of glaciations.

Early Weichselian peat at Brumunddal, southeastern Norway

Stratigraphical investigations of an inter‐till peat in Brumunddal suggest a major interstadial of Early Weichselian age. The insect fauna and the pollen composition indicate a mean July temperature 2–3d̀C lower than today during the climatic optimum. Larch and spruce immigrated at the end of the interstadial, which is tentatively correlated to the Jamtland Interstadial.

A glacial chronology for northern East Greenland

In East Greenland between 75d̀ and 76d̀N three different glacial episodes can be identified: (1) An early period with more or less total ice cover and in which the ice reached out onto the continental shelf ‐ the Kap Mackenzie stadial; (2) a period with glaciation of intermediate extent, when nunataks and a few ice‐free lowland areas existed ‐ the Muschelbjerg stadial; and (3) a final period with glacial advance, when the glaciers were mainly restricted to fjords and larger valleys ‐ the Nanok stadial. Each of these stadials was followed by a period with general deglaciation, from which marine shell‐bearing sediments have been found; the Hochstetter Forland interstadial, the Peters Bugt interstadial and the Flandrian interglacial, respectively. The marine limit sank with each of these ice‐free periods; probably an isostatic effect of the decreasing amplitude of the glacial advances. The deglaciation after the Nanok stadial began about 9500 B.P. It is not known for certain when this glacial advance started, but 13,000 B.P. or earlier is suggested. According to 14C datings the Peters Bugt interstadial dates from at least 45,000 B.P. and the Hochstetter Forland interstadial from at least 49,000 B.P. However, amino acid analyses indicate a distinct age difference between these two interstadial, and Th/U datings give age estimates of 70,000–115,000 B.P. for the Hochstetter Forland interstadial, which therefore seems to be of Early Weichselian age although a pre‐Weichselian age cannot be excluded. The same applies to the preceding Kap Mackenzie stadial. The correspondence between the present glacial chronology and similar tripartite ones on Bafffin Island, Ellesmere Island and Svalbard seems reasonably good

Stratigraphy and lithology of Late Pleistocene sediments at Møvatn, Hardangervidda, South Norway

Stratigraphic, textural, mineralogical, geochemical and palynological investigations indicate the existence of: lacustrine clay from late Eemian (Hovden thermomer); dark indicateclayey basal till of the Early Weichselian age (Hovden kryomer); lacustrine sediments from an Early or Middle Weichselian interstadial (Førnes thermomer); and basal till from Middle/ Late Weichselian (Førnes kryomer). The environment during the thermomers is discussed.