Timing and duration of growth hiatuses in mid Holocene massive Porites corals from the northern South China Sea

Growth hiatuses in massive corals are usually indicative of past ecological or environmental stresses. Among 37 fossil Porites colonies surveyed from the reef flat of Dadonghai fringing reef at Sanya, Hainan Island, northern South China Sea, seven of them were found to show clear evidence of past mortality, representing a population of ～19%. Among these samples, two of them (SYO‐13 and SYO‐28) display clear growth hiatuses reflecting mortality followed by subsequent recruitment, and five others exhibit a well‐preserved mortality surface and no subsequent recruitment. The growth hiatuses were dated using high‐precision thermal ionisation mass spectrometry U‐series techniques. The age results suggest all the dated corals formed and died in the mid Holocene. Multiple dates below the growth hiatuses suggest that SYO‐13 and SYO‐28 died at 6298 ± 11 and 6929 ± 19 a BP (i.e. years before AD 1950), respectively. Multiple dates above the growth hiatuses indicate that growth in SYO‐13 and SYO‐28 resumed at 6257 ± 14 and 6898 ± 20 a BP, respectively. The calculated durations of growth hiatuses are therefore 41 ± 18 a for SYO‐13 and 31 ± 28 a for SYO‐28, respectively, implying growth resumed within decades after the mortality events. U‐series dating of four other samples with dead heads suggests that they died at 6035 ± 53, 6059 ± 23, 6127 ± 22 and 6474 ± 24 a BP, respectively. In addition, using solution inductively coupled plasma mass spectrometry (ICP‐MS), monthly resolution Sr/Ca and Mg/Ca ratios were determined for the annual growth bands below and above the growth hiatuses for three of the dated samples. The Sr/Ca and Mg/Ca profiles indicate that the three corals probably died in different seasons (from spring to autumn), and the mortality appears to be unrelated to anomalous sea surface temperature‐induced bleaching. Copyright © 2010 John Wiley & Sons, Ltd.     

OSL dating and luminescence characteristics of aeolian deposits and their source material in Dalarna,central Sweden

Aeolian dunes, coversands, glacifluvial deltas and paraglacial mass‐movement deposits in Bonäsheden and Skattungheden in Dalarna, central Sweden were dated by optically stimulated luminescence (OSL) on quartz. The OSL ages confirm that the majority of the dunes started forming directly after deglaciation, as suggested by previous investigators. Dune formation seems to have lasted at least 1500 years, until c. 9 ka. Four younger episodes of sand drift resulting in coversand deposition were dated by OSL and/or radiocarbon to 4100±200 a, 1569–1412 cal. a BP, 970±60 a and 150±10 a. The youngest one is related to changes in land use, while the older ones may be due to regional climatic changes. The dated quartz had excellent luminescence characteristics; the luminescence was bright and dominated by the fast signal component, which made it possible to successfully analyse even untreated material, so‐called range‐finder dating. These characteristics are most likely inherited from one of the source rocks of the Quaternary deposits – the Mesoproterozoic Dala sandstone, which we show to also have very good luminescence properties.     

Mammoth tracks indicate a declining Late Pleistocene population in southwestern Alberta,Canada

Much debate has raged over the role that early humans played in this most recent large extinction. Fossil mammoth (Mammuthus primigenius) footprints were discovered at the St. Mary Reservoir in southwestern Canada (Wally's Beach DhPg-8). They are located in aeolian sediment dated at 11,300–11,000 years BP. By comparing the size distribution of these tracks with those of modern African elephants (Loxodonta africana), the age distribution of this mammoth population was determined. Containing far fewer juveniles than would be expected for an expanding or stable population, these tracks provide the first evidence that a living mammoth population, coexisting with human inhabitants, was in decline. Additionally, the same site provides corroborating evidence of humans hunting megafauna (horse and bovids). This suggests that humans, in addition to climate change, played a role in the end Pleistocene extinctions in North America.     

History of vegetation during the Holocene in the Courel and Queixa Sierras,Galicia, northwest Iberian Peninsula

Palynological studies undertaken in the mountainous regions of the northwest of the Iberian Peninsula are few in number and have been concerned largely with the second half of the Holocene. New pollen data from two Galician sierras, the Courel and Queixa Sierras, provide a 10000‐yr record of vegetation and climate change. In the Courel Sierra before 9750 yr BP, Laguna Lucenza (1420 m a.s.l.) reflects a period of open landscape covered by Poaceae and heliophilous plants, which may be correlated with the Younger Dryas. The onset of the Holocene is characterised by the expansion of oak woodland, prior to 9300 yr BP, following a short phase of birch along with the gradual decline of pine. The oak values reach a peak at 8350 ± 80 yr BP. Towards 8800 yr BP Corylus begins to expand, followed by Alnus (7500 yr BP) and Ulmus. During this period, the Fraga pollen assemblage (Queixa Sierra, 1360 m a.s.l.) indicates Betula woodland surrounding the site, masking the regional predominance of oak. After 5000 yr BP there is a gradual decrease in arboreal pollen values in both Sierras. Castanea appears in Laguna Lucenza (Courel Sierra) at 4075 ± 75 yr BP. There is widespread deforestation during the last 4000 yr. During this period the presence of large quantities of microcharcoal particles points to the occurrence of fire. The reduction in forest is associated with the arrival of cultivation at 4000 yr BP at low altitudes in the Queixa Sierra. At higher altitudes the first agricultural activity is dated at later than 2000 yr BP. This coincides with the first record of cereal cultivation at high altitude in the Courel Sierra. Copyright © 2000 John Wiley & Sons, Ltd.     

A 12.5-kyr history of vegetation dynamics and mire development with evidence of Younger Dryas larch presence in the Verkhoyansk Mountains, East Siberia, Russia

Werner, K., Tarasov, P. E., Andreev, A. A., Müller, S., Kienast, F., Zech, M., Zech, W. & Diekmann, B. 2009: A 12.5‐kyr history of vegetation dynamics and mire development with evidence of Younger Dryas larch presence in the Verkhoyansk Mountains, East Siberia, Russia. Boreas, 10.1111/j.1502‐3885.2009.00116.x. ISSN 0300‐9483. A 415 cm thick permafrost peat section from the Verkhoyansk Mountains was radiocarbon‐dated and studied using palaeobotanical and sedimentological approaches. Accumulation of organic‐rich sediment commenced in a former oxbow lake, detached from a Dyanushka River meander during the Younger Dryas stadial, at ～12.5 kyr BP. Pollen data indicate that larch trees, shrub alder and dwarf birch were abundant in the vegetation at that time. Local presence of larch during the Younger Dryas is documented by well‐preserved and radiocarbon‐dated needles and cones. The early Holocene pollen assemblages reveal high percentages of Artemisia pollen, suggesting the presence of steppe‐like communities around the site, possibly in response to a relatively warm and dry climate ～11.4–11.2 kyr BP. Both pollen and plant macrofossil data demonstrate that larch woods were common in the river valley. Remains of charcoal and pollen of Epilobium indicate fire events and mark a hiatus ～11.0–8.7 kyr BP. Changes in peat properties, C31/C27 alkane ratios and radiocarbon dates suggest that two other hiatuses occurred ～8.2–6.9 and ～6.7–0.6 kyr BP. Prior to 0.6 kyr BP, a major fire destroyed the mire surface. The upper 60 cm of the studied section is composed of aeolian sands modified in the uppermost part by the modern soil formation. For the first time, local growth of larch during the Younger Dryas has been verified in the western foreland of the Verkhoyansk Mountains (～170 km south of the Arctic Circle), thus increasing our understanding of the quick reforestation of northern Eurasia by the early Holocene.     

A submerged pine forest from the early Holocene in the Mecklenburg Lake District,northern Germany

For the first time, evidence of a submerged pine forest from the early Holocene can be documented in a central European lake. Subaquatic tree stumps were discovered in Lake Giesenschlagsee at a depth of between 2 and 5 m using scuba divers, side‐scan sonar and a remotely operated vehicle. Several erect stumps, anchored to the ground by roots, represent an in situ record of this former forest. Botanical determination revealed the stumps to be Scots pine (Pinus sylvestris) with an individual tree age of about 80 years. The trees could not be dated by means of dendrochronology, as they are older than the regional reference chronology for pine. Radiocarbon ages from the wood range from 10 880±210 to 10 370±130 cal. a BP, which is equivalent to the mid‐Preboreal to early Boreal biozones. The trees are rooted in sedge peat, which can be dated to this period as well, using pollen stratigraphical analysis. Tilting of the peat bed by 4 m indicates subsidence of the ground due to local dead ice melting, causing the trees to become submerged and preserved for millennia. Together with recently detected Lateglacial in situ tree occurrences in nearby lakes, the submerged pine forest at Giesenschlagsee represents a new and highly promising type of geo‐bio‐archive for the wider region. Comparable in situ pine remnants occur at some terrestrial (buried setting) and marine (submerged setting) sites in northern central Europe and beyond, but they partly differ in age. In general, the in situ pine finds document shifts of the zonal boreal forest ecosystem during the late Quaternary.     

Climatic cycles inferred from the aminostratigraphy and aminochronology of Quaternary dunes and palaeosols from the eastern islands of the Canary Archipelago

Aminochronological and aminostratigraphical methods have been used to study the Quaternary aeolian deposits from the islands located east of the Canary Archipelago (Fuerteventura and Lanzarote islands and La Graciosa, Montaña Clara and Alegranza islets). The extent of racemisation/epimerisation of four amino acids (isoleucine, aspartic acid, phenylalanine and glutamic acid) was measured in land snail shells of the genus Theba. The age calculation algorithms of these amino acids have been determined to permit the numerical dating of these deposits. Eight Aminozones, each defining dune/palaeosol‐formation episodes, have been distinguished and dated at 48.6 ± 6.4, 42.5 ± 6.0, 37.8 ± 4.6, 29.4 ± 4.8, 22.4 ± 4.5, 14.9 ± 3.6, 11.0 ± 4.0 and 5.4 ± 1.1 ka BP, the first five of them defining cycles of 5–7 ka. The alternation of palaeosols and aeolian deposits, which are related to abrupt transitions from humid to arid conditions, are the reflection of globally induced changes in North Africa palaeoenvironmental conditions linked to the effect of African palaeomonsoons on the trade winds and the Saharan Air Layer. Probably these aeolian cycles, with a recurrence period of 5–7 ka, are the expression of multiples of the ～2.4 ka solar‐cycle. Copyright © 2005 John Wiley & Sons, Ltd.     

The ecological implications of a Yakutian mammoth's last meal

Part of a large male woolly mammoth (Mammuthus primigenius) was preserved in permafrost in northern Yakutia. It was radiocarbon dated to ca. 18,500 ¹⁴C yr BP (ca. 22,500 cal yr BP). Dung from the lower intestine was subjected to a multiproxy array of microscopic, chemical, and molecular techniques to reconstruct the diet, the season of death, and the paleoenvironment. Pollen and plant macro-remains showed that grasses and sedges were the main food, with considerable amounts of dwarf willow twigs and a variety of herbs and mosses. Analyses of 110-bp fragments of the plastid rbcL gene amplified from DNA and of organic compounds supplemented the microscopic identifications. Fruit-bodies of dung-inhabiting Ascomycete fungi which develop after at least one week of exposure to air were found inside the intestine. Therefore the mammoth had eaten dung. It was probably mammoth dung as no bile acids were detected among the fecal biomarkers analysed. The plant assemblage and the presence of the first spring vessels of terminal tree-rings of dwarf willows indicated that the animal died in early spring. The mammoth lived in extensive cold treeless grassland vegetation interspersed with wetter, more productive meadows. The study demonstrated the paleoecological potential of several biochemical analytical techniques.     

The first radiocarbon data of bone remains of mammoth faunal forms in northwestern Russia

Unlike in the neighboring territories, the distribution and the period of habitation of late Pleistocene mammoth complex animals in the northwestern area of Russia had not been studied until recently. This article fills in this gap using the bone material from the Zoological Institute of the Russian Academy of Sciences and the collections of one of the authors. The samples of 14 bones and teeth of big mammals uncovered in different places of the region were dated. The data obtained by conventional ¹⁴C method and AMS method agree with each other and make it possible to determine two periods of habitation of mammoth complex animals in the region: 39 000–23 000 years ago and 13 000–9800 years ago, which confirms that ice-free landscapes existed here at these time intervals.     

Extinction of the woolly mammoth (Mammuthus primigenius) and woolly rhinoceros (Coelodonta antiquitatis) in Eurasia: Review of chronological and environmental issues

Kuzmin, Y. V. 2009: Extinction of the woolly mammoth (Mammuthus primigenius) and woolly rhinoceros (Coelodonta antiquitatis) in Eurasia: Review of chronological and environmental issues. Boreas, 10.1111/j.1502‐3885.2009.00122.x. ISSN 0300‐9483. The current evidence for date and environmental preferences of the extinction of two middle–late Pleistocene megafaunal species, the woolly mammoth (Mammuthus primigenius Blum.) and woolly rhinoceros (Coelodonta antiquitatis Blum.), is presented in this review. It is suggested that extinction of these large herbivores in Eurasia was closely related to landscape changes near the Pleistocene–Holocene boundary (c. 12 000–9000 uncalibrated radiocarbon years ago, yr BP), mainly involving the widespread forest formations in the temperate and arctic regions of northern Eurasia and the loss of grasslands crucial to the existence of woolly mammoth and rhinoceros. However, some woolly mammoth populations survived well into the Holocene (up to c. 3700 yr BP), showing that the process of final extinction was fairly complex, with delays in some regions of up to several millennia. The possible role of Palaeolithic humans in the extinction of Late Pleistocene megafauna is also considered.     

Chronological framework for the deglaciation of the Lake Michigan lobe of the Laurentide Ice Sheet from ice‐walled lake deposits

A revised chronological framework for the deglaciation of the Lake Michigan lobe of the south‐central Laurentide Ice Sheet is presented based on radiocarbon ages of plant macrofossils archived in the sediments of low‐relief ice‐walled lakes. We analyze the precision and accuracy of 15 AMS ¹⁴C ages of plant macrofossils obtained from a single ice‐walled lake deposit. The semi‐circular basin is about 0.72 km wide and formed of a 4‐ to 16‐m‐thick succession of loess and lacustrine sediment inset into till. The assayed material was leaves, buds and stems of Salix herbacea (snowbed willow). The pooled mean of three ages from the basal lag facies was 18 270 ± 50 ¹⁴C a BP (21 810 cal. a BP), an age that approximates the switch from active ice to stagnating conditions. The pooled mean of four ages for the youngest fossil‐bearing horizon was 17 770 ± 40 ¹⁴C a BP (21 180 cal. a BP). Material yielding the oldest and youngest ages may be obtained from sediment cores located at any place within the landform. Based on the estimated settling times of overlying barren, rhythmically bedded sand and silt, the lacustrine environment persisted for about 50 more years. At a 67% confidence level, the dated part of the ice‐walled lake succession persisted for between 210 and 860 cal. a (modal value: 610 cal. a). The deglacial age of five moraines or morainal complexes formed by the fluctuating margin of the Lake Michigan lobe have been assessed using this method. There is no overlap of time intervals documenting when ice‐walled lakes persisted on these landforms. The rapid readvances of the lobe during deglaciation after the last glacial maximum probably occurred at some point between the periods of ice‐walled lake sedimentation. Copyright © 2011 John Wiley & Sons, Ltd.     

AMS 14C chronology of the world's southernmost woolly mammoth (Mammuthus primigenius Blum.)

The world's definite southernmost woolly mammoth record is a molar from Ji’nan (around 36°N), Shandong Province, China. AMS ¹⁴C dating of the specimen, gave a conventional ¹⁴C age of 33,150±250 BP. The period of 40–30 ka BP corresponds to the later phase of the Marine Oxygen Isotope Stage 3 (MIS 3a), recognized as the global interstadial of the last glacial period. However, it is known that the winter monsoon strengthened in Asia during the period 35–33 ka BP, and the age of the woolly mammoth specimen from Ji’nan corresponds to that age. The specimen suggests that this area became cold and dry in 33 ka BP, and grassland or open forest, suitable habitat for woolly mammoths, developed during this short time span. This age is similar to the age of the southernmost woolly mammoth record in Europe, therefore supporting a hypothesis by Porter and An [1995. Correlation between climate events in the North Atlantic and China during the last glaciation. Nature 375, 305–308] that an important component of Chinese palaeoclimates may be linked to changes in North Atlantic oceanic conditions.     

Stone Age settlement and Holocene shore displacement in the Narva‐Luga Klint Bay area,eastern Gulf of Finland

Based on geological and archaeological proxies from NW Russia and NE Estonia and on GIS‐based modelling, shore displacement during the Stone Age in the Narva‐Luga Klint Bay area in the eastern Gulf of Finland was reconstructed. The reconstructed shore displacement curve displays three regressive phases in the Baltic Sea history, interrupted by the rapid Ancylus Lake and Litorina Sea transgressions c. 10.9–10.2 cal. ka BP and c. 8.5–7.3 cal. ka BP, respectively. During the Ancylus transgression the lake level rose 9 m at an average rate of about 13 mm per year, while during the Litorina transgression the sea level rose 8 m at an average rate of about 7 mm per year. The results show that the highest shoreline of Ancylus Lake at an altitude of 8–17 m a.s.l. was formed c. 10.2 cal. ka BP and that of the Litorina Sea at an altitude of 6–14 m a.s.l., c. 7.3 cal. ka BP. The oldest traces of human activity dated to 8.5–7.9 cal. ka BP are associated with the palaeo‐Narva River in the period of low water level in the Baltic basin at the beginning of the Litorina Sea transgression. The coastal settlement associated with the Litorina Sea lagoon, presently represented by 33 Stone Age sites, developed in the area c. 7.1 cal. ka BP and existed there for more than 2000 years. Transformation from the coastal settlement back to the river settlement indicates a change from a fishing‐and‐hunting economy to farming and animal husbandry c. 4.4 cal. ka BP, coinciding with the time of the overgrowing of the lagoon in the Narva‐Luga Klint Bay area.     

Kersey–Kuner terrace investigations at the Dent and Bernhardt sites,Colorado

The Dent site provided the first association of fluted points with mammoth bones in the New World. However, the stratigraphic integrity of the site has remained in doubt since the original excavations in 1932 and 1933. Core sampling at the Dent Clovis site indicates that the site, on Kersey terrace gravel, extends under railroad tracks adjacent to the original area of excavation. Four hundred meters south the Kuner strath terrace has been exposed by a roadcut at the Bernhardt site. An Archaic hearth dated 4030 ± 60 B.P. is near the top of a 1-m-thick eolian sand overlying 1 m of fine-grained alluvium dated 5740 ± 60 B.P., which in turn overlies sand and gravel of the Kuner strath terrace with an AMS radiocarbon age of 10,105 ± 90 B.P. The South Platte River appears to have been quasistable at the Kuner level during the Younger Dryas when Paleoindians from Clovis to Cody hunted megafauna on the Kersey terrace. © 1998 John Wiley & Sons, Inc.     

Molluscan successions from the Holocene tufa of St Germain‐le‐Vasson,Normandy (France) and their biogeographical significance

A detailed molluscan succession from a 10 m thick deposit of Holocene tufa at St Germain‐le‐Vasson, Normandy, provides the most complete record from northern France and has shed new light on the historical biogeography of several species of land snail. The succession has been reconstructed from four profiles and a chronology provided by accelerator mass spectrometry radiocarbon dating of charcoal, wood and shell. The onset of tufa formation occurred after 9700±90 yr BP and persisted until 4213±77 yr BP. The tufa appears to have accumulated at a remarkably constant rate (14.4–16.5 cm 100 yr^?1), except for the upper levels, where the rate increases fourfold. The succession has been divided into six local molluscan zones. An early assemblage consisting of ecologically tolerant species and those indicative of marshy grassland is replaced by a sequence of shade‐demanding taxa, reflecting the encroachment of woodland. Shaded conditions persist until the end of the sequence but the most hygrophilous elements decline after 5422±60 yr BP (zone 5), a change also reflected in the tufa lithology by the development of silty grey horizons. Notable species recovered from the tufa include Acicula fusca, Vertigo substriata, V. alpestris, V. moulinsiana (all rare or unknown living in northern France). Hygromia limbata, a twentieth century introduction to Britain, was previously thought to be a relatively recent arrival in northern France, but its record at St Germain shows that it has been present in Normandy since 6500 yr BP. Azeca goodalli, another shade‐demanding species, appeared at St Germain much later, just after 4420±65 yr BP. Several other species present in the tufa, such as Pomatias elegans, no longer live on the site, adding to the evidence for a distributional decline in Normandy and elsewhere. Perhaps the most noteworthy record is that of Leiostyla anglica, between about 8500 yr BP and 5000 yr BP, because this constitutes its only Holocene occurrence from mainland Europe. Following this discovery it seems likely that further Holocene sites with L. anglica may be found along the western seaboard of Europe connecting populations in Iberia with those of the British Isles. Copyright © 2004 John Wiley & Sons, Ltd.     

Climate changes during the last c. 7500 years as recorded by the degree of peat humification in the Lofoten region,Norway

Vorren, K.‐D., Jensen, C. E. & Nilssen, E. 2012 (January): Climate changes during the last c. 7500 years as recorded by the degree of peat humification in the Lofoten region, Norway. Boreas, Vol. 41, pp. 13–30. 10.1111/j.1502‐3885.2011.00220.x. ISSN 0300‐9483. Two peat cores from two neighbouring bogs in Lofoten, northern Norway were densely AMS dated and analysed for humification. The two cores have been influenced by human agricultural impact, especially c. 1600 cal. a BP, which may have affected the local hydrology of the bogs. From 7400 cal. a BP onwards, 19 distinct wet‐shifts are recorded in the two cores. Eight or nine of these correspond chronologically to periods of low solar activity. This correlation is most convincing during the last 2000 years. Some wet‐shifts are connected with a solar low‐activity period during the Subboreal/Subatlantic transition, which in central Europe is dated at 2750–2565 cal. a BP. For Lofoten, the corresponding Subboreal/Subatlantic transition – or the wet‐shift marking this transition – is dated at c. 2600 cal. a BP. Some wet‐shifts occur just before or just after solar low‐activity periods, but only four of the nineteen wet‐shifts are clearly not temporally connected with periods of low solar activity. Compared with the wet‐shifts in NW European (mainly British Isles) bogs, there are more frequent wet‐shifts in northern Norway. Compared with other peat cores in northern Norway, especially for the interval 6500–5000 cal. a BP, Lofoten deviates by its lack of wet‐shifts. As in England, Scotland and Ireland, there is regional variability in the temporal formation of wet‐shifts in northern Norway.     

Deglaciation history of Lake Ladoga (northwestern Russia) based on varved sediments

Lake Ladoga in northwestern Russia is Europe's largest lake. The postglacial history of the Ladoga basin is for the first time documented continuously with high temporal resolution in the upper 13.3 m of a sediment core (Co1309) from the northwestern part of the lake. We applied a multiproxy approach including radiographic imaging, (bio‐)geochemical and granulometric analyses. Age control was established combining radiocarbon dating with varve chronology, the latter anchored to a correlated radiocarbon age from a lake close by. The age‐depth model reveals the onset of glacial varve sedimentation at 13 910±140 cal. a BP, when Lake Ladoga was part of the Baltic Ice Lake. Linear extrapolation of published retreat rates of the Scandinavian Ice Sheet provides a formation age of the Luga moraine close to Lake Ladoga's southern shore of 14.5–15.9 cal. ka BP, older than previously assumed. Varve sedimentation covers the Bølling/Allerød interstadial, the Younger Dryas stadial and the Early Holocene. Varve‐thickness variations, conjoined with grain‐size and geochemical variations, inform about the relative position of the Scandinavian Ice Sheet and the climate during the deglaciation phase. The upper limit of the varved succession marks the change from glaciolacustrine to normal lacustrine sedimentation and post‐dates the drainage of the Baltic Ice Lake as well as the formation of the Salpausselkä II moraine north of Lake Ladoga, by c. 250 years. The Holocene sediment record is divided into three periods in the following order: (i) a lower transition zone between the Holocene boundary and c. 9.5 cal. ka BP, characterized by mostly massive sediments with low organic content, (ii) a phase with increased organic content from c. 9.5 to 4.5 cal. ka BP corresponding to the Holocene Thermal Maximum, and (iii) a phase with relatively stable sedimentation in a lacustrine environment from c. 4.5 cal. ka BP until present.     

Pleistocene fluvial sediments,palaeontology and archaeology of the upper River Thames at Latton,Wiltshire, England

Pleistocene fluvial sediments of the Northmoor Member of the Upper Thames Formation exposed at Latton, Wiltshire, record episodic deposition close to the Churn–Thames confluence possibly spanning the interval from Marine Isotope Stages (MIS) 7 to 2. The sequence is dominated by gravel facies, indicating deposition by a high‐energy, gravel‐bed river. A number of fine‐grained organic sediment bodies within the sequence have yielded palaeoenvironmental and biostratigraphical data from Mollusca, Coleoptera, vertebrates, pollen and plant macrofossils. The basal deposit (Facies Association A) contains faunal material indicating temperate conditions. Most of the palaeontological evidence including a distinctive small form of mammoth (Mammuthus cf. trogontherii), together with the U‐series age estimate of >147.4 ± 20 kyr suggest correlation with MIS 7. The overlying deposits (Facies Associations B and C) represent deposition under a range of climatic conditions. Two fine‐grained organic deposits occurred within Association B; one (Association Ba) in the northern part of the pit as a channel fill and the other (Association Bb) in its southern part as a scour‐fill deposit. The coleopteran assemblages from Ba, indicate that it accumulated under temperate oceanic conditions, while Bb, which also yielded a radiocarbon age estimate of 39 560 ± 780 ¹⁴C yr BP, was formed under much colder and more continental climatic conditions. The sequence is considered to represent deposition within an alluvial fan formed at the Churn–Thames confluence; a depositional scenario which may account for the juxtaposition of sediments and fossils of widely differing age within the same altitudinal range. Copyright © 2006 John Wiley & Sons, Ltd.     

A 10Be‐based reconstruction of the last deglaciation in southern Sweden

We present 23 cosmogenic surface exposure ages from 10 localities in southern Sweden. The new ¹⁰Be ages allow a direct correlation between the east and west coasts of southern Sweden, based on the same dating technique, and provide new information about the deglaciation of the Fennoscandian Ice Sheet in the circum‐Baltic area. In western Skåne, southernmost Sweden, a single cosmogenic surface exposure sample gave an age of 16.8±1.0 ka, whereas two samples from the central part of Skåne gave ages of 17.0±0.9 and 14.1±0.8 ka. Further northeast, in southern Småland, two localities gave ages ranging from 15.2±0.8 to 16.9±0.9 ka (n=5) indicating a somewhat earlier deglaciation of the area than has previously been suggested. Our third locality, in S Småland, gave ages ranging from 10.2±0.5 to 18.4±1.6 ka (n=3), which are probably not representative of the timing of deglaciation. In central Småland one locality was dated to 14.5±0.8 ka (n=3), whereas our northernmost locality, situated in northern Småland, was dated to 13.8±0.8 ka (n=3). Samples from the island of Gotland suggest deglaciation before 13 ka ago. We combined the new ¹⁰Be ages with previously published deglaciation ages to constrain the deglaciation chronology of southern Sweden. The combined deglaciation chronology suggests a rather steady deglaciation in southern Sweden starting at c. 17.9 cal. ka BP in NW Skåne and reaching northern Småland, ～200 km further north, c. 13.8 ka ago. Overall the new deglaciation ages agree reasonably well with existing deglaciation chronologies, but suggest a somewhat earlier deglaciation in Småland.