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J. Rose - One of the best experts on this subject based on the ideXlab platform.

  • The Dimlington Stadial/Dimlington Chronozone: a proposal for naming the main glacial episode of the Late Devensian in Britain
    Boreas, 2008
    Co-Authors: J. Rose
    Abstract:

    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-stage.

  • the dimlington stadial dimlington chronozone a proposal for naming the main glacial episode of the late Devensian in britain
    Boreas, 2008
    Co-Authors: J. Rose
    Abstract:

    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-stage.

  • Late Devensian glaciation, ice-dammed lake and river diversion, Stiffkey, north Norfolk, England
    Proceedings of the Yorkshire Geological Society, 2002
    Co-Authors: D. Brand, S.j. Booth, J. Rose
    Abstract:

    SUMMARY A sequence of disturbed and undisturbed samples from a borehole drilled at Warham, near Stiffkey in north Norfolk, is described and sub-divided into three lithofacies on the basis of sedimentary structures, particle size distribution, calcium carbonate content, selected heavy mineral composition and indicator lithologies. These properties are used to determine the environment of deposition and establish correlation with glaciogenic deposits elsewhere. The basal sands and gravels (Lithofacies A) overlie the Chalk bedrock and are interpreted as having formed by a braided River Stiffkey that flowed northward through the site in pre-Late Devensian periglacial conditions. Lithofacies B consists of >8 m of laminated sands, silts and clays that were formed in a proglacial lake created by the obstruction of the River Stiffkey when the Late Devensian (Dimlington Stadial) glaciation reached the north Norfolk coast. These sediments are covered by gravelly sands (Lithofacies C), which were deposited as an ice-marginal river deposit as part of the Late Devensian end moraine-ridge complex. Finally, the lake drained and the sediments were dissected as the diverted River Stiffkey adopted a new course to the north-east and the lower, incised section of the present Stiffkey valley was formed.

Winifred Pennington - One of the best experts on this subject based on the ideXlab platform.

  • A chronostratigraphic comparison of Late‐Weichselian and Late‐Devensian subdivisions, illustrated by two radiocarbon‐dated profiles from western Britain
    Boreas, 2008
    Co-Authors: Winifred Pennington
    Abstract:

    14C-dated percentage and absolute late-glacial pollen diagrams from (1) Blelham Bog, north-west England and (2) Cam Loch, north-west Scotland arc subdivided into chronozones Bolling, Older Dryas, Allerod, and Younger Dryas as proposed for the Late-Weichselian sequence by Mangerud et al., Boreas 3 (1974), with boundaries defined in conventional 14C years. It is shown how these chronozone boundaries coincide in the two British pollen diagrams with boundaries between pollen assemblage zones which are interpreted as the results of environmental (climatic) changes. Differences between the pollen zones found in western Britain and those of the classic South Scandinavian profiles, which are interpreted as the consequence of regional differentiation in the vegetation of north-west Europe circa 14,500 to 10,000 years ago, pose serious problems in the correlation of Late-Weichselian and Late-Devensian subdivisions on the basis of pollen assemblage zones, but a chronostratigraphical classification makes it possible to compare the Late-Devensian profiles from western Britain with the Late-Weichselian subdivisions of Mangerud et al., in which ‘chronozone boundaries seem to be climatically conditioned within southern Scandinavia’.

  • a chronostratigraphic comparison of late weichselian and late Devensian subdivisions illustrated by two radiocarbon dated profiles from western britain
    Boreas, 2008
    Co-Authors: Winifred Pennington
    Abstract:

    14C-dated percentage and absolute late-glacial pollen diagrams from (1) Blelham Bog, north-west England and (2) Cam Loch, north-west Scotland arc subdivided into chronozones Bolling, Older Dryas, Allerod, and Younger Dryas as proposed for the Late-Weichselian sequence by Mangerud et al., Boreas 3 (1974), with boundaries defined in conventional 14C years. It is shown how these chronozone boundaries coincide in the two British pollen diagrams with boundaries between pollen assemblage zones which are interpreted as the results of environmental (climatic) changes. Differences between the pollen zones found in western Britain and those of the classic South Scandinavian profiles, which are interpreted as the consequence of regional differentiation in the vegetation of north-west Europe circa 14,500 to 10,000 years ago, pose serious problems in the correlation of Late-Weichselian and Late-Devensian subdivisions on the basis of pollen assemblage zones, but a chronostratigraphical classification makes it possible to compare the Late-Devensian profiles from western Britain with the Late-Weichselian subdivisions of Mangerud et al., in which ‘chronozone boundaries seem to be climatically conditioned within southern Scandinavia’.

Robin Wingfield - One of the best experts on this subject based on the ideXlab platform.

  • the extension of the late weichselian late Devensian ice sheets in the north sea basin
    Journal of Quaternary Science, 1991
    Co-Authors: Jürgen Ehlers, Robin Wingfield
    Abstract:

    The distribution of large channel-like features, comprising Weichselian/Devensian incisions, in the western North Sea provides evidence for a much larger extension of the last ice sheet than currently assumed. Morphological comparison of the incisions with those in North Germany and Poland reveals a striking similarity in shape and distribution. The features on the North Sea floor are interpreted as being formed by meltwater erosion within the margin of the ice sheet. The widespread absence of Weichselian/Devensian till in the area under consideration may be attributed to later erosion. Large-scale reworking and redistribution of sediments is indicated by the complete sediment infill of the majority of the incisions.

  • The extension of the Late Weichselian/Late Devensian ice sheets in the North Sea Basin
    Journal of Quaternary Science, 1991
    Co-Authors: Jürgen Ehlers, Robin Wingfield
    Abstract:

    The distribution of large channel-like features, comprising Weichselian/Devensian incisions, in the western North Sea provides evidence for a much larger extension of the last ice sheet than currently assumed. Morphological comparison of the incisions with those in North Germany and Poland reveals a striking similarity in shape and distribution. The features on the North Sea floor are interpreted as being formed by meltwater erosion within the margin of the ice sheet. The widespread absence of Weichselian/Devensian till in the area under consideration may be attributed to later erosion. Large-scale reworking and redistribution of sediments is indicated by the complete sediment infill of the majority of the incisions.

Adrian M Hall - One of the best experts on this subject based on the ideXlab platform.

  • middle to late Devensian glaciation of north east scotland implications for the north eastern quadrant of the last british irish ice sheet
    Journal of Quaternary Science, 2017
    Co-Authors: J W Merritt, Rodger E Connell, Adrian M Hall
    Abstract:

    We present a review of over 175 years of research into the Middle to Late Devensian (Weichselian) glaciation of north-east Scotland based crucially on both its lithostratigraphic and geomorphic records. The location of the region, and surrounding seabed, makes this unusually detailed record significant for deciphering the former interactions and dynamics of Scottish and Scandinavian ice within the North Sea Basin (NSB), which continue to be controversial. A twelve-stage event stratigraphy is proposed based on a parsimonious interpretation of stratigraphic relationships, till lithology and regional clast fabrics, striae, subglacial bedforms, ice-marginal features and published geochronometry at critical sites. The record of regional glaciation supports converging evidence that the north-eastern quadrant of the last British and Irish Ice Sheet (BIIS) reached its maximum spatial extent in the late Middle- to early Late Devensian and later re-expanded following widespread internal glacial reorganisations, marine transgression and partial retreat from the central NSB. Retreat was interrupted by several glacial readvances of limited extent. Field-captured data helps identify important events that are not clearly resolved from remote sensing alone, particularly regarding growth phases of the last glaciation.

  • Middle to Late Devensian glaciation of north‐east Scotland: implications for the north‐eastern quadrant of the last British–Irish ice sheet
    Journal of Quaternary Science, 2016
    Co-Authors: Jon Merritt, E. Rodger Connell, Adrian M Hall
    Abstract:

    We present a review of over 175 years of research into the Middle to Late Devensian (Weichselian) glaciation of north-east Scotland based crucially on both its lithostratigraphic and geomorphic records. The location of the region, and surrounding seabed, makes this unusually detailed record significant for deciphering the former interactions and dynamics of Scottish and Scandinavian ice within the North Sea Basin (NSB), which continue to be controversial. A twelve-stage event stratigraphy is proposed based on a parsimonious interpretation of stratigraphic relationships, till lithology and regional clast fabrics, striae, subglacial bedforms, ice-marginal features and published geochronometry at critical sites. The record of regional glaciation supports converging evidence that the north-eastern quadrant of the last British and Irish Ice Sheet (BIIS) reached its maximum spatial extent in the late Middle- to early Late Devensian and later re-expanded following widespread internal glacial reorganisations, marine transgression and partial retreat from the central NSB. Retreat was interrupted by several glacial readvances of limited extent. Field-captured data helps identify important events that are not clearly resolved from remote sensing alone, particularly regarding growth phases of the last glaciation.

  • Devensian organic interstadial deposits and ice sheet extent in buchan scotland
    Journal of Quaternary Science, 1998
    Co-Authors: Graeme Whittington, Adrian M Hall, Kevin J. Edwards, Rodger E Connell, Russell G Coope, Peter D Hulme, J Jarvis
    Abstract:

    Pre-Late Devensian organic deposits in the Buchan area of northeast Scotland were investigated for their geomorphological and palaeoecological (pollen, plant macrofossils, coleoptera) properties. Close ecological agreement exists between fossil indicators and allows the inference that the environment in the vicinity of the deposits was a dwarf shrub tundra of the type met today in high latitude areas of Scandinavia and arctic Russia. The latest in a series of radiocarbon dates from the site produced determinations beyond the limits of the method, although the geomorphological and fossil evidence appears to point to an interstadial date within Oxygen Isotope Stages 5a or 5c. The site has special significance for arguments concerning the much-debated concept of ‘Moraineless Buchan’; indeed, evidence is presented which supports the concept of extensive ice sheet glaciation during the Late Devensian for this crucial geographical area. If Buchan is to be seen as a further casualty amongst other disputed ice-free enclaves, then a return to earlier models of extensive ice sheet glaciation in the Late Devensian of Scotland would seem to be necessary. © 1998 John Wiley & Sons, Ltd.

  • Middle Devensian ice-proximal gravels at Howe of Byth, Grampian Region
    Scottish Journal of Geology, 1995
    Co-Authors: Adrian M Hall, Jack Jarvis, Geoff A.t. Duller, Ann G. Wintle
    Abstract:

    Synopsis Ice-proximal glaciofluvial gravels at Howe of Byth, Grampian Region, have given luminescence ages of 45 ± 4 and 37±4 ka BP. The gravels were laid down by meltwater draining from an ice margin in the Moray Firth and provide the first firm evidence of extensive glaciation in NE Scotland during the Mid Devensian.

  • Luminescence dating and its application to key pre-Late Devensian sites in Scotland
    Quaternary Science Reviews, 1995
    Co-Authors: Geoffrey A. T. Duller, Ann G. Wintle, Adrian M Hall
    Abstract:

    Abstract Relatively few sites have been identified in Scotland that contain records that predate the peak of the Late Devensian glaciation (ca. 18 ka BP). Where such records have been identified they have assumed a key role in developing our understanding of climate change in Scotland. Radiocarbon dating has been the primary chronological tool applied to these sites, but the reliability of age determinations in excess of 30 ka is questionable. In this paper we describe the results of a programme which applies luminescence dating methods to eight key pre-Late Devensian sites in Scotland. Methods were developed and tested to enable the identification of samples for which luminescence dating was only able to provide an upper limit on the age because of the limited light exposure that the sample experienced at deposition. These new approaches were applied to four sites where independent age control was available; this meant that the choice of sediments from test sites was restricted to those sediments which were formed in the last 40,000 years and hence were amenable to radiocarbon dating. The luminescence age estimates for the control sites and the pre-Late Devensian sites are discussed within the context of any existing chronological control on a site by site basis.

D. J. Case - One of the best experts on this subject based on the ideXlab platform.