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Henry P. Schwarcz - One of the best experts on this subject based on the ideXlab platform.

Rob Westaway - One of the best experts on this subject based on the ideXlab platform.

  • improved age constraint for pre and post anglian temperate stage deposits in north norfolk uk from analysis of serine decomposition in bithynia opercula
    Journal of Quaternary Science, 2010
    Co-Authors: Rob Westaway
    Abstract:

    The ‘new glacial stratigraphy’ (NGS) of Britain postulates that deposits hitherto assigned to the Anglian glaciation in Marine Isotope Stage (MIS) 12 represent MIS 16, 12, 10 and 6. This controversial idea can be tested at Sidestrand in north Norfolk, where fossiliferous temperate-stage deposits underlie the oldest and overlie the youngest of the glacial deposits. Previous work has considered biostratigraphy and amino acid dating of these temperate-stage deposits, but did not achieve tight age constraint using the amino acid evidence alone. The total hydrolysable amino acid fraction in intra-crystalline protein from Bithynia tentaculata opercula has previously been analysed for concentrations of serine and alanine. Statistical screening of these data gives alanine/serine ratios of 4.572 ± 0.114 for the Sidestrand Hall Member (beneath the glacial deposits) and 3.564 ± 0.091 for the Sidestrand Cliff Formation (overlying the glacial deposits). These ratios imply ages of MIS 13a and 11c, respectively, indicating the latest Cromerian and early Hoxnian interglacials and invalidating the NGS. Copyright © 2009 John Wiley & Sons, Ltd.

Charles Turner - One of the best experts on this subject based on the ideXlab platform.

  • u series dating of Hoxnian interglacial deposits at marks tey essex england
    Journal of Quaternary Science, 1999
    Co-Authors: Peter Rowe, T C Atkinson, Charles Turner
    Abstract:

    A U-Th dating study was carried out on the authigenic carbonate component of interglacial lake sediments at Marks Tey, Essex, England. Isochron methods were necessary because of the presence of non-carbonate detritus. Calculated dates around the limit of the U-Th method were obtained for two horizons. Error limits were determined by Monte Carlo sampling from the normal distributions of errors in the isotope ratios. Comparison of the resulting empirical distribution functions with the marine oxygen isotope time-scale indicates with 87% confidence that the Marks Tey sediments correlate with OIS 11 or some older stage. As the Marks Tey deposits rest without stratigraphical break on Anglian till, and can be firmly correlated with the Hoxnian interglacial type site at Hoxne, Suffolk, England, this result implies that the Anglian glaciation took place in OIS 12 acid the Hoxnian Stage of the British chronostratigraphy commenced in OIS 11. Copyright (C) 1999 John Wiley & Sons, Ltd.

  • U‐series dating of Hoxnian interglacial deposits at Marks Tey, Essex, England
    Journal of Quaternary Science, 1999
    Co-Authors: Peter Rowe, Tim Atkinson, Charles Turner
    Abstract:

    A U-Th dating study was carried out on the authigenic carbonate component of interglacial lake sediments at Marks Tey, Essex, England. Isochron methods were necessary because of the presence of non-carbonate detritus. Calculated dates around the limit of the U-Th method were obtained for two horizons. Error limits were determined by Monte Carlo sampling from the normal distributions of errors in the isotope ratios. Comparison of the resulting empirical distribution functions with the marine oxygen isotope time-scale indicates with 87% confidence that the Marks Tey sediments correlate with OIS 11 or some older stage. As the Marks Tey deposits rest without stratigraphical break on Anglian till, and can be firmly correlated with the Hoxnian interglacial type site at Hoxne, Suffolk, England, this result implies that the Anglian glaciation took place in OIS 12 acid the Hoxnian Stage of the British chronostratigraphy commenced in OIS 11. Copyright (C) 1999 John Wiley & Sons, Ltd.

Simon G. Lewis - One of the best experts on this subject based on the ideXlab platform.

  • Terrestrial environments during MIS 11: evidence from the Palaeolithic site at West Stow, Suffolk, UK
    Quaternary Science Reviews, 2007
    Co-Authors: Richard C. Preece, Ian Candy, Kirsty Penkman, Tim Atkinson, Simon A. Parfitt, David R. Bridgland, Simon G. Lewis, P.j. Rowe, N.c. Debenham, Edward J. Rhodes
    Abstract:

    Abstract Multidisciplinary investigations of the sequence at Beeches Pit, West Stow (Suffolk, UK), have a direct bearing the age of the Hoxnian Interglacial and its correlation with the continental Holsteinian and with the global marine record. At this site, glacial deposits (till and outwash gravels) referable to the Anglian Lowestoft Formation fill a subglacial channel cut in Chalk bedrock. Above these glacial deposits a series of interglacial sediments occurs, consisting of limnic, tufaceous and colluvial silts, lacking pollen but rich in shells, ostracods and vertebrates. Lower Palaeolithic flint artefacts of Acheulian character have also been recovered, including refitting examples. Charred material is abundant at certain horizons and many of the bones have been burned. Several discrete areas of burnt sediment are interpreted as hearths. The molluscan fauna comprises some 78 taxa and includes species of considerable zoogeographical and biostratigraphical importance. The land snail assemblage from the tufa consists of woodland taxa with no modern analogue, including species that are either extinct (e.g. Zonitoides sepultus) or which no longer live in Britain (e.g. Platyla polita, P. similis, Neniatlanta pauli). This is also the type locality of Retinella (Lyrodiscus) skertchlyi, which belongs to a subgenus of zonitid land snail now living only on the Canary Islands. There are indications from this fauna (‘the Lyrodiscus biome’) that the climate was wetter and perhaps warmer than the present day. The vertebrate fauna is also noteworthy with species of open habitats, such as rabbit (Oryctolagus cf. cuniculus), and of closed forest, such as squirrel (Sciurus sp.) and garden dormouse (Eliomys quercinus) present at different times. The occurrence of southern thermophiles, such as Aesculapian snake (Zamenis longissimus), indicates temperatures warmer than those of eastern England today. The upper levels include much material reworked from the interglacial sediments, although there is clear faunal evidence for climatic deterioration. Both the molluscan and vertebrate faunas suggest correlation of the interglacial sediments with the Hoxnian. Uranium series dates from the tufa (∼455 ka BP), TL dates from burnt flints (414±30 ka BP) and a range of amino acid racemization data all support correlation of this interglacial with MIS 11. However, four OSL dates from sand beneath the interglacial sequence yield a mean age of 261±31 ka BP, far younger than all other age determinations and far younger than implied by the biostratigraphy. Archaeologically the site is unusual in showing prolonged human occupation within closed deciduous forest and evidence for controlled use of fire in a Lower Palaeolithic context. Biostratigraphical correlations with other Lower Palaeolithic sites support the suggestion that Acheulian and Clactonian industries both occurred in southern Britain during the same substage of the Hoxnian, although not necessarily at precisely the same time. The characteristics of the MIS 11 interglacial in Britain are discussed in the light of evidence from Beeches Pit and elsewhere.

  • humans in the Hoxnian habitat context and fire use at beeches pit west stow suffolk uk
    Journal of Quaternary Science, 2006
    Co-Authors: R C Preece, Simon A. Parfitt, David R. Bridgland, John Gowlett, Simon G. Lewis
    Abstract:

    A Lower Palaeolithic industry at Beeches Pit, West Stow, Suffolk, occurs within an interglacial sequence that immediately overlies glacial deposits, referable to the Anglian Lowestoft Formation. There is strong biostratigraphical evidence from both vertebrates and molluscs that the interglacial represented is the Hoxnian (MIS 11). This conclusion is supported by uranium series dates from carbonate nodules (>400 kyr), TL dates from burnt flint (414 � 30 kyr) and a range of amino acid racemisation data. The archaeology consists of flint artefacts of Acheulian character, including many refitting examples. Charred material is abundant in three stratigraphical units and many bones and flints have been burnt, indicating repeated occurrence of fire. Several discrete areas of burnt sediment appear to be hearths. This interpretation is supported by: (1) the intensity of burning (600-8008C) implied by the charred and calcined bones; (2) the intersection of two of the burnt areas, implying separate burning events at slightly different, overlapping locations; (3) the discovery of two burnt flakes that refit onto an adjacent group that are unburnt, indicating that the burning was highly localised; and (4) the spatial distribution of artefacts respects the features interpreted as hearths, suggesting fireside knapping. Fossils associated with the archaeology indicate occupation within closed deciduous forest in a fully temperate climate. Attractions to this unusual environment would have included the fresh water provided by springs, a rich supply of potential food and a prolific source of good quality flint for tool manufacture. The archaeological evidence therefore suggests that the site repeatedly served as an area of focused activities (perhaps a 'home-base') during much of the interglacial. The upper levels of the sequence provide clear faunal evidence of climatic deterioration during which human occupation and fire use persisted. Biostratigraphical correlations with other Lower Palaeolithic sites lend support to the suggestion that Acheulian and Clactonian industries occurred in Britain during the same substage of the Hoxnian, although not necessarily at precisely the same time. Copyright # 2006 John Wiley & Sons, Ltd.

  • Humans in the Hoxnian: habitat, context and fire use at Beeches Pit, West Stow, Suffolk, UK†
    Journal of Quaternary Science, 2006
    Co-Authors: Richard C. Preece, Simon A. Parfitt, David R. Bridgland, John Gowlett, Simon G. Lewis
    Abstract:

    A Lower Palaeolithic industry at Beeches Pit, West Stow, Suffolk, occurs within an interglacial sequence that immediately overlies glacial deposits, referable to the Anglian Lowestoft Formation. There is strong biostratigraphical evidence from both vertebrates and molluscs that the interglacial represented is the Hoxnian (MIS 11). This conclusion is supported by uranium series dates from carbonate nodules (>400 kyr), TL dates from burnt flint (414 � 30 kyr) and a range of amino acid racemisation data. The archaeology consists of flint artefacts of Acheulian character, including many refitting examples. Charred material is abundant in three stratigraphical units and many bones and flints have been burnt, indicating repeated occurrence of fire. Several discrete areas of burnt sediment appear to be hearths. This interpretation is supported by: (1) the intensity of burning (600-8008C) implied by the charred and calcined bones; (2) the intersection of two of the burnt areas, implying separate burning events at slightly different, overlapping locations; (3) the discovery of two burnt flakes that refit onto an adjacent group that are unburnt, indicating that the burning was highly localised; and (4) the spatial distribution of artefacts respects the features interpreted as hearths, suggesting fireside knapping. Fossils associated with the archaeology indicate occupation within closed deciduous forest in a fully temperate climate. Attractions to this unusual environment would have included the fresh water provided by springs, a rich supply of potential food and a prolific source of good quality flint for tool manufacture. The archaeological evidence therefore suggests that the site repeatedly served as an area of focused activities (perhaps a 'home-base') during much of the interglacial. The upper levels of the sequence provide clear faunal evidence of climatic deterioration during which human occupation and fire use persisted. Biostratigraphical correlations with other Lower Palaeolithic sites lend support to the suggestion that Acheulian and Clactonian industries occurred in Britain during the same substage of the Hoxnian, although not necessarily at precisely the same time. Copyright # 2006 John Wiley & Sons, Ltd.

  • Middle Pleistocene deposits at Frog Hall Pit, Stretton‐on‐Dunsmore, Warwickshire, English Midlands, and their implications for the age of the type Wolstonian
    Journal of Quaternary Science, 1997
    Co-Authors: D. H. Keen, R. L. Jones, Mh Field, G.r. Coope, Simon G. Lewis, Huw I. Griffiths, D Q Bowen
    Abstract:

    Organic sediment from Frog Hall Pit, near Coventry, has produced pollen, plant macrofossil, insect, ostracod and molluscan data indicative of the early part of a temperate episode in the Middle Pleistocene. The regional stratigraphy and clast lithological characteristics of the gravels underlying the temperate deposits show that the whole sequence at the site post-dates the major glaciation (the Wolstonian sensu Mitchell et al., 1973) of the Midlands. Amino-acid D/L ratios from molluscan shells give mean values of 0.24, which is consistent with an age in Oxygen Isotope Stage 9 and comparable with those from the Hoxnian Interglacial of East Anglia. This age-estimate for the Frog Hall organic deposit places a minimum age on the Wolstonian Glaciation of the Midlands in Oxygen Isotope Stage 10, and therefore close in time to the Anglian (Oxygen Isotope Stage 12) Cold Stage. © 1997 John Wiley & Sons, Ltd.

T C Atkinson - One of the best experts on this subject based on the ideXlab platform.

  • u series dating of Hoxnian interglacial deposits at marks tey essex england
    Journal of Quaternary Science, 1999
    Co-Authors: Peter Rowe, T C Atkinson, Charles Turner
    Abstract:

    A U-Th dating study was carried out on the authigenic carbonate component of interglacial lake sediments at Marks Tey, Essex, England. Isochron methods were necessary because of the presence of non-carbonate detritus. Calculated dates around the limit of the U-Th method were obtained for two horizons. Error limits were determined by Monte Carlo sampling from the normal distributions of errors in the isotope ratios. Comparison of the resulting empirical distribution functions with the marine oxygen isotope time-scale indicates with 87% confidence that the Marks Tey sediments correlate with OIS 11 or some older stage. As the Marks Tey deposits rest without stratigraphical break on Anglian till, and can be firmly correlated with the Hoxnian interglacial type site at Hoxne, Suffolk, England, this result implies that the Anglian glaciation took place in OIS 12 acid the Hoxnian Stage of the British chronostratigraphy commenced in OIS 11. Copyright (C) 1999 John Wiley & Sons, Ltd.