摘要:

Thermoluminescence (TL) dating of shallow marine sediments from the well studied interglacial‐carly glacial sequence at Fjtfsangcr, western Norway has yielded ages that with few exceptions become progressively older with depth. For Ecmian samples the TL method yielded a mean of 111,000 ± 23,000 years, close to the often postulated age of 125,000 years. For the Early Weichselian the TL dates were younger than suggested by the amino‐acid me

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00315.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Pollen analysis of the organic surface (FH) horizon of a radiocarbon‐dated palaeopodzol buried beneath the ‘Little Ice Age’ outer moraine of Haugabreen west of the Jostedalsbrecn ice‐cap, southern Norway, provided evidence for environmental change in the area between ca. 4,000 B. P. and the 13th century A. D. Radiocarbon dating of the profile, apart from providing a chronology for the changes interpreted, also allowed estimation of pollen incorporation rates into the soil which can be compared with pollen influx rates established elsewhere. Two periods of local woodland recession were identified, the first between ca. 3,300 B. P. and ca. 3,600 B. P., after the initiation of the FH horizon, and the second in the 13th century A. D. at the onset of the Little

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00316.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Borehole samples of glacial sands from Caldy, Wirral contained bubble structures which have not been found inin situexposures of the corresponding materials. It is believed that the sands liquefied during driving of the sampler, destroying previous structures and developing a bubble structure by release of pore‐air during liquefaction. The sands conform generally to the grading characteristics previously defined for sands prone to liquefaction. Their propensity to liquefy was confirmed by laboratory test

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00317.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Book reviewed in this article:Madsen, David B.&O'Connell, James F. (eds.) 1982:Man and Environment in the Grear Basin.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00318.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Quaternary sediments cored on the continental slope off the Grand Banks and on nearby seamounts and abyssal hills have been correlated back to at least isotopic stage 6. using lithologic and hioslratigraphic markers and warm‐cold cyclicity in microfossil assemblages. The sequence is dated using limited oxygen isotope andl4C data. The oldest continental slope cores penetrate to a glacial stade with an extrapolated age of 50. 0(H) B. P. The oldest scamount cores probably penetrate to isotopic stage 13. Watcrmass distribution over the area results from interaction of the Labrador Current with locally generated shelf water, and to a lesser extent, the Gulf Stream. Planktic foraminiferal assemblages and sedimentological evidence suggest that arctic Labrador Current core water extends onto the eastern Grand Banks only during full interglacials. During intcrstadials, this arctic core water is absent, probably because its source‐was blocked by ice. Cold water during stadials probably results mostly from local cooling on the continental sh

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00319.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00320.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The sedimentology of three sand‐cored drumlins in central Ulster. Northern Ireland is described. The sand‐cores of the drumlins consist of complex sequences of cohesive sediment gravity forms, grain‐flow deposits, turbiditic sands and deltaic sands and gravels, showing complex fades relationships. The bulk of the sediments formed in water‐filled cavities associated with a major subglacial meltwater escape route excavated in bedrock. The sand‐cores are overlain by a streamlined carapace of basal melt‐out till. A model is presented to account for spatial variations in faeies arrangement within the sand‐cores. Three specific meltwater depositional subenvironments were recognised: (1) main channel axis, (2) main channel flank, and (3) minor tributary channel. The sand‐cores formed prior to the main phase of basal melt‐out till deposition and before dru

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00321.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Pollen diagrams of 10 peat sections taken in sedge tundra span as much as 10.730 radiocarbon years and show a varied sequence of pollen assemblages dominated by herbs and shrubs. Taxa, for the most part. belong to the Gramineae. Cyperaceae.Salix, Abuts, BeiulaandEmpelrum.The assemblages indicate scral changes in the vegetation, resulting from interaction of climate and of successive ashfalls from regional volcanoes, and suggest a patchwork of late Quaternary plant communities. This record from southernmost Beringia enlarges upon previous pollen records from the Aleutian Islands and from the southern part of the Bering land bridge region in western Alaska.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00322.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Book reviewed in this article:Géographie Physique el Quaternaire1982: Vol. XXXV

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00323.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Pollen analysis of a radiocarbon‐dated core from a shallow basin in volcanic hills in eastern Scotland revealed the existence of Late Devensian and Flandrian deposits. Much of the vegetation history of the Flandrian proved to be missing due to a hiatus in the profile. The Late Devensian pollen record included anomalous arboreal taxa of three possible origins: contamination, long‐distance wind transport and reworking of interstadial material. Because of lacking information on Late Devensian climates and the location of thermophilous arboreal refugia in Europe a re‐examination of supposedly contaminated British Late Devensian pollen records might well be rewa

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00324.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY