摘要:

Magnetic measurements made on sediment and catchment samples from two contrasting Icelandic lakes show how susceptibility and saturation isothermal remanent magnetisation alter as magnetic minerals pass from rock to soil to stream and into the lakes. There is no detectable growth of secondary magnetic minerals in Icelandic soil profiles and susceptibility peaks in the 62.5–1000 μm size range of mineral particles in the lake sediments. Changes in sediment source can be detected using combinations of magnetic measuremen

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00720.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Book reviewed in this article:Horic, Shoji (ed.) 1984:Lake Biwa. Dr W. Junk Publishers, Kluwer Academic Publishers Group

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00721.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Three to four km southwest of Egtved, in middle Jutland, diggings for a gas pipeline cut through a form which is believed to be a fossil frost mound. The horizontal outline of the form is that of a rounded silty body with a diameter of about 45 m. It is surrounded by layered eolian sand of which the layers are bent upwards into a vertical position close to the silty body. A small bulge of silty material is present on top of the neighbouring sand. The mechanism for the formation of the form is thought to have much in common with that of the hydrostatic system pingo of Mackay. It cannot be determined whether the mound was annual or perennial, but the presence of silty sediment in the central part shows that liquified sediment moved upward to fill the present form. By means of lithostratigraphy and pollen analysis, the development and decay of the mound were dated to Late Dryas time. It is suggested that similar features may be present in other parts of Scandinavia outside the area glaciated during the Late Dryas.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00722.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Book reviewed in this article:Price, Robert J. 1983:Scotland's Environment During the Last 30,000 years

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00723.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The term Dimlington Stadial is proposed as a climatostratigraphic name fer the main glacial episode of the Late Devensian in Britain, in preference to stratigraphically unsatisfactory terms, such as Late Devensian Glaciation (which includes the Windermere Interstadial and the Loch Lomond Stadial), icesheet glaciation or maximum of ice expansion, that are currently in use. The name is selected from a site on the East Yorkshire coast and refers to the interval between 26,000 and 13,000 radiocarbon years B.P. Dimlington Chronozone is the formal chronostratigraphic term for the equivalent period of time, and comprises the main part of the Late Devensian Sub‐stag

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00724.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The loess component of a solifluction deposit of the Dimlington Stadial exposed at the inland site of Eppleworth in eastern England gave a thermoluminescence date of 17.5 ± 1.6 × 103years. The solifluction deposit is overlain by a slightly weathered till correlated with the Skipsea Till of coastal exposures. which lies between organic horizons with radiocarbon dates of 18,500–18,240 B.P. and 13,045 B.P. Although the till must have been deposited during the Dimlington Stadial (after 18,240 B.P. at Dimlington and after 17,500 B.P. at Epplcworth), it gave apparent TL dates of 42.1 ± 3.6 × 103years at Eppleworth and 102 ± 9 × 103years at Dimlington, indicating that the components of the till were not exposed to light immediately before dep

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00725.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

The southwestern part of the Laurentidc Ice Sheet, in central North America, repeatedly surged during the last part of the Wisconsin Glaciation. Evidence includes the extreme lobation of the ice margin, the gentle slopes of lateral moraines and other marginal features, a radiocarbon chronology indicating extremely rapid marginal advance and retreat, and the abundance of supraglacial flow till. Rapid ice movement was caused by subglacial water and was probably limited to areas of slowly permeable substrate, which slowed the escape of the water.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00726.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Book reviewed in this article:Delcourt, Paul A., Delcourt, Hazel R.&Webb, Thompson 1984:Atlas of Mapped Distributions of Dominance and Modern Pollen Percentages for Important Tree Taxa of Eastern North America

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00727.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00728.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

Quantitative studies of foraminifera and radiolaria, semi‐quantitative analyses of diatoms and coccoliths, and the distribution of ice‐rafted sediments have been performed on cores from the southeastern Norwegian Sea. The results document large variations in sea‐surface temperatures and ocean circulation, showing a strong correlation between oceanic data and palaeoclimatic data from the neighbouring coastal areas of Norway. For the first time the Allerød – Younger Dryas climatic fluctuations and the Holocene climatic optimum are shown in records from the Norwegian Sea. Starting at about 13,000 B.P. the sea surface became seasonally ice‐free with productive seasons. During the Allerød a narrow wedge of temperate Atlantic water flowed into the southeastern Norwegian Sea. In Younger Dryas time the surface waters cooled by several degrees. Holocene surface conditions were relatively constant, with somewhat higher temperatures in a period possibly corresponding with At

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1985.tb00729.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY