摘要:

Four soil profiles within c. 4 ha of dry heathland on lping Common, southeastern England were studied. Two were podzols, one was a buried profile from beneath a Bronze‐age barrow and one was a profile buried beneath sediment in a small pond. Loss on ignition, particle size analysis, iron concentration and pollen concentration were determined and a pollen diagram prepared for each profile. It is suggested that discrete soil pollen assemblage zones arise from their incorporation by successively shallower‐burrowing earthworm populations as the soils and vegetation change from mull to mor types. The implications of this mode of incorporation to the interpretation of soil pollen diagrams are discussed. A sequence of vegetation and soils for this area is suggested as follows:(1) mixed deciduous woodland of Quercus. Tilia and Corylus with a fern‐rich understorey growing in a mull soil, (2) scrub woodland of Betula and Corylus with Pteridium and some Callunu, (3) Calluna heathland on podzolised soils.14C dates obtained from podzol Bh horizons and the buried soil beneath the pond were inconcl

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00352.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Tree stumps in a standing position have been discovered in 20 to 40 meters of water in Toyama Bay, Japan. Radiocarbon dated samples from two of these stumps yielded ages of 8.480±70 and 9.060±80 years B.P., indicating that the stumps are remnants of a forest that existed during thc early Holocen

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00353.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Books reviewed in this article:Bowen. D. O.(ed.) 1982: Quaternary Science Reviews.

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00354.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

This method for determining total roundness of clast fractions takes into account both the abrasion and the crushing processes. It is developed from a slightly modified visual estimation method and a newly defined parameter ‐ crushing processes. Based on visual estimation, the method is most useful as a tool for the Quternary field geologis

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00355.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.tb00356.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

The recognition of materials and structures which are unrelated to the original floodplain processes of terrace formation is essential to the proper understanding of terrace morphology and stratigraphy. Two groups of processes have been active in modifying the Lower and Middle Pleistocene terraces of the River Thames since their formation: non‐fluvial deposition; and structural rearrangement by subsidence associated with solution of the underlying Chalk. Non‐fluvial deposits comprise solifluction gravels which are variable in character and may incorporate a range of pre‐existing deposits; and brickearths which appear in most cases to be redistributed loess mixed with non‐loessic components. The distinction between fluvial and non‐fluvial deposits is made using particle size, composition and fabric analysis. Structural rearrangement of terrace sediments has occurred due to subsidence into deep, narrow, steep‐sided pipes. Within such pipes, disturbance of primary structures and fabrics is severe. Over a wider area. primary bedding may be inclined towards pipes, and sediments may show evidence of shearing, faulting and brecciation. Interpretative problems arising from post‐depositional modification ar

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00357.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Books reviewed in this article:Hughes, M. K., Kelly, P. M., Pilcher, J. R.,&LaMarchc, Jr., V. C. (eds.) 1982:Climate from Tree Rings

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00358.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Sediments from the peat‐bog La Muzelle (Massif des Ecrins, Iserc, France, alt. 2,150 m) were analyzed. The site was reached by aPinusforest and anAbiesforest during the Allerød and the Atlantic, and during the Bølling a shrubland was noted. Forests have been degrading into lawns without intermediary heath long before the appearance of the first signs of human action. The glacier has been receding ever since the Late Würm, except during the Younger Dryas when big frontal moraines were formed close to the peat‐bog. The nature of the sediments allowed a determination of several frontal positions of the glacier. No notable re‐advance could be evidenced during the Older or Oldest Dryas nor during the Holocene; only a minor oscillation may have occurred at the beginning of the

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00359.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY

摘要:

Ice‐marginal debris‐flow deposits (comparable to deposits elsewhere described as flow tills) are described from glacier‐proximal sediments in an Alpine foreland area. Debris‐flow deposits are characteristically interstratified with subaeric or subaquatie meltwater deposits, and occur in a wide variety of geomorpho‐logical settings. The granulomctric composition of debris‐flow deposits is more variable than that of subglacial tills. Within‐flow variability may occur as a result of the formation of graded bedding, lateral as well as vertical. Clast fabrics show both random and preferred orientations; unequivocal interpretation of these is not possible. Debris‐flow deposits are composed of material derived from various sources: sources from subglaeially‐derived debris as well as from previously deposited tills and walerlain sediments ca

ISSN:0300-9483    

DOI:10.1111/j.1502-3885.1983.tb00360.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.tb00361.x

出版商:Blackwell Publishing Ltd    

年代:1983

数据来源: WILEY