摘要:

Fourteen lake basins on and west of Mt. Billingen have been analysed with respect to different stratigraphic methods: pollen, diatoms, other microfossils,14C datings, lithology, grain‐size distribution and chemical characteristics. The aim has been to establish a well‐dated pollen stratigraphy for the area in order to date when lakes west of Mt. Billingen were raised above sea level. Previous studies and results from the area have also been included in the study. Distance diagrams, with different tilting directions, have been constructed. A shore displacement curve fromc. 11,300 toc. 9,300 B.P., based on the most probable tilting direction, shows a complex uplift picture. A rather low regression gradient (3–4 m/100 years) duringc. 1,000 years was, atc. 10,200 B.P., followed by a distinctly increasing gradient (8–9 m/100 years) followed by a marked gradient decrease atc. 9,500 B.P. The latter was possibly caused by a distinct sea level transgression on the Swedish West Coast. Indications of a short transgression around 10,000 B.P. as well as the possibly complicated course of isolation of Lake Vänern from the sea are also discussed. Finally the shore displacement is related to the deglaciation of the area and the supposed two drainages of the Baltic

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00734.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00735.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Studies of freshwater Harperleas Reservoir, Scotland, during periods of falling water level, have revealed the extensive development of traces made by the amphipodGammarus(the ‘freshwater shrimp’) in subaerially‐exposed marginal sediments. The traces comprise networks of near‐surface, fragile, unlined, tubular burrows, 2–4 mm in diameter. In places these merge into 1–2 mm wide, irregular surface trails. This paper is believed to be the first descriptive account of lebensspuren made byGammarus, fossil forms of which may possibly be preserved in rocks dating back to the Eocene. Although several species ofGammarusare tolerant of saline waters it is suggested that the traces may, in association with other lines of evidence, be of use in the interpretation of depositional e

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00736.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00737.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Book reviewed in this article:Caine Nel 1983:The Mountains of Northeastern Tasmania. A Study of Alpine Geomorphology

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00738.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

During the last glaciation of northern Ellesmere Island many areas remained ice‐free. A caribou antler from deglacial‐marine sediments in Clements Markham Inlet dates 8,415 ± 135 B.P. (S‐2501). If locally derived it places caribou at the northern limit of their contemporary range at the onset of deglaciation in this area. Immediately to the south, on the Hazen Plateau, ice remained at its limit untilc. 8,000 B.P. Therefore, this antler may indicate the presence of caribou during full glacia

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00739.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Kahasa. J. (ed) IY84: Quorrrriury of South Afrierrco and Antarctic Penusula A. A. Balksma. Rotterdam.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00740.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Ice‐dammed lake Boverbrevatnet existed for 75–125 years in the ‘Little Ice Age’. After about A.D. 1826, glacier retreat led to a fall in lake level and to exposure of the former shoreline, which includes well‐developed platforms cut in metamorphic bedrock. The rock platforms, up to 5.3 m wide and backed by cliffs up to 1.55 m high, are partially covered by large angular boulders which form pavements. Accurate levelling has permitted correlation of platform fragments, overflow cols and related features of the shoreline, such as benches eroded in moraines, ice‐push ridges, a perched delta, vegetation trim‐lines, lichen limits and a ‘lichen‐kill’ zone. The evolution of the lake, the chronology of deglaciation and the period of formation of the rock platforms have been dated by lichenometry, supported by14C dating, Schmidt hammer ‘R’‐values and historical data. The morphology of the rock platforms, together with estimates of their rate of erosion ranging from 1.4 to 7.1 cm/year, indicate the importance of frost shattering (frost riving, frost wedging or macrogelivation) at the lake margin under a periglacial climate, while the permanence of such platforms as landscape features suggests their use in the reconstruction of former periglacial environments. A semi‐quantitative model is outlined for the development of rock platforms which emphasises deep penetration of the annual freeze‐thaw cycle, the movement of unfrozen lake water towards the freezing plane, and the growth of segregation ice in fissures and cracks at the interface between lake ice and bedrock. Ice‐push and ice‐pull processes are involved primarily as transporting agents in the formation of boulder pavements and in the removal of debris from the platforms. Analogous processes may occur on polar coasts

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00741.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Moraine ridges have been morphologically and seismically identified in the south‐western Barents Sea. Some of these ridges were deposited in front of ice lobes from the northern part of the Fennoscandian Ice Sheet, others in front of glaciers located on the southern Barents Sea shelf. The moraine ridges were probably deposited during the Weichselian, possibly the Late Weichselia

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00742.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Book reviewed in this article:Mahaney, W. C. (ed.) 1984:Correlation of Quarternary Chronologies

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1986.tb00743.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY