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1.
Comparatively little research has been undertaken on relative sea‐level (RSL) change in western Iceland. This paper presents the results of diatom, tephrochronological and radiocarbon analyses on six isolation basins and two coastal lowland sediment cores from the Stykkishólmur area, northern Snæfellsnes, western Iceland. The analyses provide a reconstruction of Lateglacial to mid‐Holocene RSL changes in the region. The marine limit is measured to 65–69 m above sea level (asl), with formation being estimated at 13.5 cal ka BP. RSL fall initially occurred rapidly following marine limit formation, until ca. 12.6 cal ka BP, when the rate of RSL fall decreased. RSL fell below present in the Stykkishólmur area during the early Holocene (by ca. 10 cal ka BP). The rates of RSL change noted in the Stykkishólmur area demonstrate lesser ice thicknesses in Snæfellsnes than Vestfirðir during the Younger Dryas, when viewed in the regional context. Consequently, the data provide an insight into patterns of glacio‐isostatic adjustment surrounding Breiðafjörður, a hypothesized major ice stream at the Last Glacial Maximum.  相似文献   

2.
Mt. Kroppefjall is situated just south of the Middle Swedish (Younger Dryas) ice-marginal zone. Its abundance of lake basins makes it very suitable for detailed shore displacement studies close to the Younger Dryas ice margin. Altogether 12 lakes at altitudes between 157 and 78 m were studied and all but one situated above the marine limit contained marine sediments. The dating of their isolation from the sea resulted in a shore displacement curve from c. 11,200 to c. 98M)BP. The relative uplift almost ceased between 10,900 and 10,300 BP, which is mainly related to an ice readvance in the Lake Vanern basin. This period of balance between uplift and sea level rise was preceded by a relative uplift rate of 5 m/lW yr and followed by as high rates as 7–8 m/100 yr, possibly caused by a delayed uplift effect and perhaps also a local fall in sea level caused by the rapidly receding ice margin. The time difference between the formation of two delta surfaces at Odskolts Moar is estimated at 60&800 years. Shoreline diagrams along the Swedish west and east coasts, mainly based on a number of shore displacement curves, reveal large anomalies that are believed to have been caused by dammings and drainages of the Baltic basin. The southwards extrapolated shorelines indicate that the bedrock threshold in the Oresund Strait, between Denmark and Sweden, functioned as the outlet threshold for the Baltic Ice Lake during its dammed stages, while the erosion of the Store Balt and Darss Sill straits began at the culmination of the Ancylus transgression and continued during the rapid IS20 m Ancylus regression.  相似文献   

3.
Lake-level fluctuations in the Jura mountains (France) during the Younger Dryas and the early Holocene are reconstructed using sedimentological analyses. Major transgressive phases culminated just before the Laacher See tephra deposition, at the beginning of the Younger Dryas, between 9000 and 8000 BP and between 7000 and 6000 BP. The Younger Dryas appears to be characterized by increasing dryness. Other major lowering phases occurred during the middle Allerød and during the Preboreal. A transgressive event developed between c . 9700 and 9500 BP. These palaeohydrological changes can be related to climatic oscillations reconstructed from pollen and isotopic records in Swiss lakes, from glacier movements and timberline variations in the Alps, and from isotopic records in the Greenland ice sheet.  相似文献   

4.
Romundset, A., Lohne, Ø. S., Mangerud, J. & Svendsen, J. I. 2009: The first Holocene relative sea-level curve from the middle part of Hardangerfjorden, western Norway. Boreas , 10.1111/j.1502-3885.2009.00108.x. ISSN 0300-9483.
The first relative sea-level (RSL) curve from the mid-Hardangerfjorden area covering the entire Holocene is presented. The curve is based on a series of AMS 14C dates on terrestrial plant macrofossils across the isolation level in each of five lakes located between 3.5 and 74.5 m a.s.l. During the first 1200 years, the RSL fell very rapidly from the marine limit at 98 m a.s.l. to 33 m a.s.l., i.e. at a rate of 5.4 cm yr−1. The emergence rate then slowed considerably and was close to standstill 8000–6500 cal. yr BP. However, an emergence of 16.5 m has taken place during the past 6000 years. Radiocarbon dates of terrestrial plant macrofossils from the basal strata in a lake above the marine limit and mollusc shells from glaciomarine silt in the isolation basins yielded a mean age for the local ice-margin retreat of 11 300 cal. yr BP. This verifies that Hardangerfjorden was glaciated during the Younger Dryas – an interpretation that has recently been disputed. The ice margin retreated at a rate of about 300 m yr−1 from the position of the Younger Dryas moraine to this site some 60 km further into the fjord.  相似文献   

5.
Deglaciation took place in eastern Jämtland and Ångermanland in central Sweden c . 10 500–10 200 cal. yr BP. In the present study, vegetation development and shore displacement during the earliest ice-free period are investigated by 14C dating of sediment from six isolated lake basins and by pollen analysis. A brief but distinct peak in Hippophaë occurs in all pollen diagrams coincident with basin isolation, followed by up to 500 years (varying locally) by an Alnus rise. The Alnus curve does not display a synchronous rise in the area. Its expansion below the highest shore level is time-transgressive and controlled mainly by the timing of basin isolation. The relationship between regional Alnus expansion and changes in hydrology and climate is discussed. The pollen diagrams show Pinus predominance with Corylus to the east (more coastal areas) and Betula predominance (though less pronounced) to the west during the period 10 200–9000 cal. yr BP. However, comparisons between sites suggest marked variability in the forest development. Shore displacement in easternmost Jämtland c . 10 300–9000 cal. yr BP is equal to or slightly more rapid than that of SE Ångermanland, contrary to the present pattern of isostatic recovery. A rapid shore level regression c . 10 300–10 000 cal. yr BP may be related to drainage of the Ancylus Lake.  相似文献   

6.
Late Weichselian sea level changes at Sotra, Hordaland, western Norway   总被引：1，自引：0，他引：1  
Sediments from twenty-eight basins were surveyed; ten of these basins with a representative lithostrati-gfaphy wee studied to determine their isolation from the sea during Late Weichselian. Diatom analysis was used to determine salinity changes, which were dated by pollen analysis and the radiocarbon method. The area was deglaciated in the early Boiling, and a regression of about 5 m followed. A transgression of more than 10 m started in late Boiling and terminated in middle Younger Dryas, with a transgression maximum between 38.2 and 40 m above present sea level. All the investigated basins were finally isolated in late Younger Dryas/early Preboreal, during a rapid regression. Repeated cycles of chinophilous/ chinophobous plant communities in the area reflect climatic changes in the period. No evidence of an Older Dryas ice readvance was found.  相似文献   

7.
The shore displacement during the Holocene in southeastern Ångermanland, Sweden, has been investigated by means of radiocarbon-dating of isolation intervals in sediment cores from a total of nine new basins. Results from earlier investigations have been used in complement. There is a forced regression in the area from c. 9300 BP ( c . 10500 cal. yr BP) until c . 8000 BP ( c . 9000 cal. yr BP), on average c . 8 m/100 years, after which there is a gradually slowing regression of c . 2.5–1.0 m/100 years up to the present time. The most rapid regression occurs during the later phase of the Ancylus Lake stage, 9500–9000 cal. yr BP. There is no evidence of halts in the regression. Crustal uplift in the area since deglaciation is c . 310 m. The deglaciation of southeastern Ångermanland took place c . 9300 BP ( c . 10500 cal. yr BP); this is c . 900 years earlier than the age given by clay varve dating. The shore displacement curve provides a means of estimating the difference between the clay varve time scale and calibrated radiocarbon dates, by comparison with varve-dated altitudes of alluvial deltas of the River Ångermanalven. From c. 2500 to c. 8000 cal. BP there is a deficit in clay varves of some 300 years; further back in time this discrepancy increases significantly. The main explanation for the discrepancy is most likely lacking varves in the time-span 8500–10200 cal. yr BP, located along the upper reaches of River Ångermanalven below the highest shore level.  相似文献   

8.
Sediment cores recovered from four emerged lakes (54, 41, 22, and 7 m a.s.l.) provide new data on the deglaciation and relative sea-level history of the Murman coast, Kola Peninsula. The transition from marine to lacustrine sediment is identified in the cores by analysis of sediment physical properties and diatom assemblages. Fourteen AMS-radiocarbon ages on organic macrofossils isolated from core sediment provide chronology for the records. Basal ages from two of the cores indicate deglaciation of the area prior to 11000 BP. Radiocarbon ages associated with the marine-lacustrine sediment transition in the cores further constrain the emergence history of the area. The prominent late-glacial shoreline on the Murman coast (48 m a.s.l.) is dated to c . 10500–10300 BP, the emergence ages of lake basins 54 and 41 m a.s.l. Glaciofluvial terraces graded to this shore level indicate remnant glaciers on the north-central Kola Peninsula during the Younger Dryas.  相似文献   

9.
Rundgren, M., Ingólfsson, Ó., Björck, S., Jiang, H. & Haflioason, H. 1997 (September): Dynamic sea-level change during the last deglaciation of northern Iceland. Boreas , Vol. 26, pp. 201–215. Oslo. ISSN 0300–9483.
A detailed reconstruction of deglacial relative sea-level changes at the northern coast of Iceland, based on the litho- and biostratigraphy of lake basins, indicates an overall fall in relative sea level of about 45 m between 11300 and 9100 BP, corresponding to an isostatic rebound of 77 m. The overall regression was interrupted by two minor transgressions during the late Younger Dryas and in early Preboreal, and these were probably caused by a combination of expansions of local ice caps and readvances of the Icelandic inland ice-sheet margin. Maximum absolute uplift rates are recorded during the regressional phase between the two transgressions (10000–9850 BP), with a mean value of c . 15 cm 14C yr-1 or 11–12 cm cal. yr-1. Mean absolute uplift during the regressional phase following the second transgression (9700–9100 BP) was around 6 cm 14C yr-1, corresponding to c . 3 cm cal. yr-1, and relative sea level dropped below present-day sea level at 9000 BP.  相似文献   

10.
In recent years, major advances have been made in our understanding of Late Quaternary sea-level changes in western Scotland. In particular, new hypotheses have been advanced to explain the ages and origins of high-level rock platform fragments and high-level marine shell beds. Certain raised shorelines in Islay and Jura, SW Argyll and Wester Ross have been related to former margins of the last ice sheet and are associated with drops in the Lateglacial marine limit. In some areas the decline in Lateglacial sea-level took place in association with a stationary ice margin while in others the fall in sea-level occurred in conjunction with considerable ice retreat.During the Lateglacial Interstadial, relative sea-level fell rapidly between ca. 13 and ca. 12 ka BP and thereafter more slowly until ca. 11 ka BP. Renewed marine erosion during the cold climate of the Loch Lomond (Younger Dryas) Stadial (ca. 11-10 ka BP) resulted in the production of the Main Lateglacial Shoreline, which declines in altitude to the W, SW and S away from the centre of glacio-isostatic uplift in the W Highlands. The shoreline has a maximum altitude of 10–11 m O.D. in the Oban area and passes below sea-level in NE Islay, Ardnamurchan, Colonsay, W Mull, Kintyre and Arran.During the early Holocene a pronounced marine transgression took place, probably culminating between 6.6 and 7.0 ka BP. The culmination of the transgression is represented by the Main Postglacial Shoreline that reaches a maximum altitude of ca. 14 m in the Oban area and declines gently in altitude away from the centre of glacio-isostatic uplift. Reconstruction of the uplift isobases for this shoreline appears to indicate a slight eastward migration of the uplift centre since the Younger Dryas. In peripheral areas of western Scotland the Main Postglacial Shoreline is not present owing to the effect of Holocene submergence.  相似文献   

11.
The study of a c. 18 m thick Late Weichselian- Early Holocene (isotope stage 2/1) marine succession (original water depth 100–150 m) from the Skagen 3 borehole, northern Denmark, has led to a better understanding of the palaeoenvironmental changes during the last deglaciation. The palaeoenvironmental interpretation is based on benthic foraminifera, stable isotope composition and lithology, whereas the chronostratigraphy and sedimentation rates are based on AMS radiocarbon dates. Marine conditions were established in the area at between 15 000 and 14 500 BP (reservoir corrected 14C years), and the first influence of Atlantic water masses imported through the Norwegian Channel is registered from 13 100 BP to 10 900BP (the Bølling- Allerrad interstadial complex). This was followed by the Younger Dryas cooling event between 10 900 and 10 100 BP. The hydrographic change at the Pleistocene-Holocene transition after the Younger Dryas occurred in two stages. Arctic/subarctic deep-water assemblages persisted continuously at Skagen after the first stage at 10 200 BP, while cold boreal assemblages existed in shallower water environments in the Kattegat-Skagerrak basin during the same period of time. The slight warming in the early Holocene seems to have been interrupted by a short-term cooling at about 9700–9600 BP. Finally, at 9600 BP the arrival of warm Atlantic water masses created full-interglacial conditions in the whole region.  相似文献   

12.
A clay varve chronology has been established for the Late Weichselian ice recession east of Mt. Billingen in Västergötland, Sweden. In this area the Middle-Swedish end moraine zone was built up as a consequence of cold climate during the Younger Dryas stadial. A change-over from rapid to slow retreat as a result of climatic deterioration at the Alleröd/Younger Dryas transition cannot be traced with certainty in the varve sequences, but it seems to have taken place just before 11,600 varve years BP. The following deglaciation was very slow for about 700 years — within the Middle-Swedish end moraine zone the annual ice-front retreat was only c . 10 m on average. A considerable time-lag is to be expected between the Younger Dryas climatic event and this period of slow retreat. The 700 years of slow retreat were succeeded by 200 years of more rapid recession, about 50–75 m annually, and then by a mainly rapid and uncomplicated retreat of the ice-front by 100–200 m/year or more, characterizing the next 1500 years of deglaciation in south and central Sweden. The change from about 50–75 m to 100–200 m of annual ice-front retreat may reflect the Younger Dryas/Preboreal transition. Clay-stratigraph-ically defined, the transition is dated at c . 10,740 varve years BP, with an error of +100 to -250 years. In the countings of ice layers in Greenland ice cores (GRIP and GISP-2) the end of the Younger Dryas climatic event is 800–900 years older. However, a climatic amelioration after the cold part of the Younger Dryas and in early Preboreal should rapidly be reflected by for example chemical components and dust in Greenland ice cores, and by increasing δ13C content in tree rings. On the other hand, the start of a rapid retreat of the inland ice margin can be delayed by several centuries. This can explain at least a part of the discrepancy between the time-scales.  相似文献   

13.
Late- and postglacial history of the Great Belt, Denmark   总被引：3，自引：0，他引：3  
On the basis of shallow seismic records, vibrocoring, macrofossil analyses and AMS radiocarbon-dating, five stratigraphical units have been distinguished from the deepest parts of the central Great Belt (Storebælt) in southern Scandinavia. Widespread glacial deposits are followed by two lateglacial units confined to deeply incised channels and separated by an erosional boundary. Lateglacial Unit I dates from the time interval from the last deglaciation to the Allerød; lateglacial Unit II is of Younger Dryas age. Early Holocene deposits show a development from river deposits and lake-shore deposits to large lake deposits, corresponding to a rising shore level. Lake deposits are found up to 20 m below the sea floor, and the lake extended over some 200–300 km2. The early Holocene freshwater deposits are dated to the time interval c. 10900 to c. 8800 cal. yr BP and the oldest shells of marine molluscs from the Great Belt are dated to c. 8100 cal. yr BP.  相似文献   

14.
The coastal zone of Norrbotten, northern Sweden, was gradually inundated by the Ancylus Lake following the retreating ice margin and forming a highest coastline approximately 210 m above the present sea level. The succeeding shore displacement is reconstructed based on lithological investigations and radiocarbon datings of identified isolation sequences from 12 cored lake basins. The highest lake basins, along with two basins above the highest shoreline, suggest ice-free conditions already at 10 500 cal. yr BP. This is at least 500 years earlier than previously thought and implies rapid ice-sheet break-up in the Gulf of Bothnia. The shore displacement (RSL) curve represents a forced regression of successively decreasing rate through the Holocene, from 9 m/100 yr to 0.8 m/100 yr. During the first 1000-1200 years, the isostatic uplift is exponentially declining, followed by a constant uplift rate from c. 9500 cal. yr BP to 5500-5000 cal. yr BP. The last 5000 years seem to be characterized by a low but constant rebound rate. The development of the Ancylus Lake stage of the Baltic may also be discerned in the Norrbotten RSL curve, suggesting that the chronology of the Ancylus Lake stages may have to be revised. The Littorina transgression is also reflected by the RSL curve shape. In addition, a series of early to mid-Holocene beach terraces were OSL-dated to allow for comparison with the 14C-dated shore displacement curve. Interpretations of these ages and their relation to former sea levels were clearly more problematic than the dating of the lake basin isolations.  相似文献   

15.
Northern Folgefonna (c. 23 km2), is a nearly circular maritime ice cap located on the Folgefonna Peninsula in Hardanger, western Norway. By combining the position of marginal moraines with AMS radiocarbon dated glacier‐meltwater induced sediments in proglacial lakes draining northern Folgefonna, a continuous high‐resolution record of variations in glacier size and equilibrium‐line altitudes (ELAs) during the Lateglacial and early Holocene has been obtained. After the termination of the Younger Dryas (c. 11 500 cal. yr BP), a short‐lived (100–150 years) climatically induced glacier readvance termed the ‘Jondal Event 1’ occurred within the ‘Preboreal Oscillation’ (PBO) c. 11 100 cal. yr BP. Bracketed to 10 550–10 450 cal. yr BP, a second glacier readvance is named the ‘Jondal Event 2’. A third readvance occurred about 10 000 cal. yr BP and corresponds with the ‘Erdalen Event 1’ recorded at Jostedalsbreen. An exponential relationship between mean solid winter precipitation and ablation‐season temperature at the ELA of Norwegian glaciers is used to reconstruct former variations in winter precipitation based on the corresponding ELA and an independent proxy for summer temperature. Compared to the present, the Younger Dryas was much colder and drier, the ‘Jondal Event 1’/PBO was colder and somewhat drier, and the ‘Jondal Event 2’ was much wetter. The ‘Erdalen Event 1’ started as rather dry and terminated as somewhat wetter. Variations in glacier magnitude/ELAs and corresponding palaeoclimatic reconstructions at northern Folgefonna suggest that low‐altitude cirque glaciers (lowest altitude of marginal moraines 290 m) in the area existed for the last time during the Younger Dryas. These low‐altitude cirque glaciers of suggested Younger Dryas age do not fit into the previous reconstructions of the Younger Dryas ice sheet in Hardanger. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

16.
A detailed shoreline displacement curve documents the Younger Dryas transgression in western Norway. The relative sea‐level rise was more than 9 m in an area which subsequently experienced an emergence of almost 60 m. The sea‐level curve is based on the stratigraphy of six isolation basins with bedrock thresholds. Effort has been made to establish an accurate chronology using a calendar year time‐scale by 14C wiggle matching and the use of time synchronic markers (the Vedde Ash Bed and the post‐glacial rise in Betula (birch) pollen). The sea‐level curve demonstrates that the Younger Dryas transgression started close to the Allerød–Younger Dryas transition and that the high stand was reached only 200 yr before the Younger Dryas–Holocene boundary. The sea level remained at the high stand for about 300 yr and 100 yr into Holocene it started to fall rapidly. The peak of the Younger Dryas transgression occurred simultaneously with the maximum extent of the ice‐sheet readvance in the area. Our results support earlier geophysical modelling concluding a causal relationship between the Younger Dryas glacier advance and Younger Dryas transgression in western Norway. We argue that the sea‐level curve indicates that the Younger Dryas glacial advance started in the late Allerød or close to the Allerød–Younger Dryas transition. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

17.
This is the first of a series of articles presenting the results of a multi-proxy investigation aimed at reconstructing changes in the ecosystem and climate of Whitrig Bog, SE Scotland, during the last glacial-inter-glacial transition (Devensian Lateglacial, c . 14–10 ka BP). We present here the results from sediment lithology, chemistry, pollen, and plant macrofossil analyses. These data are used to infer the nature of the local catchment soils and both local and regional terrestrial vegetation. The interstadial period ( c . 13–11 ka BP) is characterized by a successional sequence developing from a landscape with bare, poorly developed minerogenic soils supporting a sparse herbaceous flora into open birch woodland with juniper scrub and stable organic soils. At c . 11 ka BP the Younger Dryas climatic cooling event caused an abrupt reversion to an open herbaceous arctic/alpine flora (e.g. macrofossil evidence of Silene furcata and Oxyria digyna ) and high levels of minerogenic erosion into the basin, indicating environmental response to a cold Arctic climate. In addition to this Younger Dryas climatic reversal, two lesser reversion episodes occurred earlier during the interstadial. The more pronounced of the two, late in the intersladial, is characterized by high levels of erosion and a change from birch/juniper woodland to an open herbaceous flora. The older oscillation occurs approximately mid-way through the interstadial sequence and is marked by similar pollen changes, albeit shorter lived and more subtle.  相似文献   

18.
The deglaciation history of the Malangen‐Målselv fjord and valley area proximally to the Tromsø‐Lyngen (Younger Dryas) moraine at Bakkejord, Malangen, northern Norway, is reconstructed based on morphostratigraphic, lithostratigraphic and geophysical evidence, and 25 radiocarbon dates from marine shells and foraminifera. The results show that following the Skarpnes event c. 12 200 14Cyr BP, and prior to the Younger Dryas readvance, the area was deglaciated at least as far as Sandmo situated 22 km proximally to the Tromsø‐Lyngen moraine. Two moraine ridges crossing the fjord at Sandmo and buried beneath thick glaciomarine sediments are correlated with this period. The area was subsequently deglaciated between 10 300 and 9200 14Cyr BP, following the Tromsø‐Lyngen (Younger Dryas) readvance. Five ice‐front accumulations post‐dating the Tromsø‐Lyngen moraine and situated 19, 27, 42, 55 and 77 km behind it are identified and dated based on radiocarbon dates and correlation of marine limits: Målsnes (c. 10 050 14Cyr BP), Kjerresnes (c. 10 000 14Cyr BP), Solli (c. 9750 14Cyr BP), Bardufoss‐Brentmoen‐Storskogmoen (c. 9600–9700 14Cyr BP) and Alapmoen (c. 9200 Cyr BP). The largest of these, at Bardufoss‐Storskogmoen, possibly accumulated as a response to an ice advance. Fourteen dates of apparent late Allerød/Younger Dryas age (11 100–10 000 14Cyr BP), obtained from fossils in glaciomarine sediments in the Målselv valley up to 77 km proximally to the Tromsø‐Lyngen moraine, are interpreted as postdating rather than predating this moraine. Several of these are considered to be too old because of uncertain reservoir age, carbon‐dating plateaus and/or contamination. This highlights uncertainties associated with radiocarbon‐dating and the profound effect such uncertainties may have on interpreting geological events.  相似文献   

19.
Younger Dryas事件与北黄海泥炭层的形成   总被引：1，自引：0，他引：1  
形成于海平面变化处于停滞阶段和湿润气候条件下的泥炭层是古环境变化信息的重要载体。对北黄海4个含泥炭层的沉积剖面进行研究后发现,其均集中在渤海海峡入口处,水深变化在50～54m。泥炭层的AMS14C年龄在10650～1010014 CaBP,与发生在11000～1000014 CaBP间的末次冰消气候回冷事件——Younger Dryas(YD)事件在年代上非常吻合,表明北黄海泥炭层的形成可能与YD事件的全球效应密切相关,可作为YD事件在北黄海陆架响应的一个重要证据。泥炭层在北黄海的集中出现说明,冰后期的海平面上升过程中在YD事件期间存在停滞阶段,这一时期海面已经达到渤海海峡外侧,并可能在此徘徊了近千年。此外,泥炭层的大量出现和孢粉记录表明YD事件发生期间约为10600～1020014 CaBP,此时北黄海可能处在寒冷而湿润的环境。这一发现与全球范围内大部分YD事件的海陆记录存在明显差异,说明不同地区对YD事件的响应存在差异,不能简单地利用单一的干冷模式来分析YD事件在区域上的响应特征和过程。  相似文献   

20.
Marine transgression in Younger Dryas in Norway   总被引：1，自引：0，他引：1  
BOREAS Anundsen, K. 1978 03 01: Marine transgression in Younger Dryas in Norway. Boreas, Vol. 7, pp. 49–60. Oslo. ISSN 0300–9483.
The lithostratigraphy and biostratigraphy of sediment cores from two basins in southwestern Norway have been studied and radiocarbon dated. The diatom and the Hystrix content indicates a marine Younger Dryas transgression that reached its maximum level at the transition Younger Dryas/Preboreal Chronozone. No Allerød transgression to the same altitude can be demonstrated, and the suggested Allerød transgression at Bømlo (Faegri 1944) is most likely of Younger Dryas age, too.  相似文献   

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