The back-barrier and barrier depositional history of Romney Marsh, Walland Marsh and Dungeness, Kent, England, by Antony J. Long and James B. Innes, published September 1995 in Journal of Quaternary Science (vol. 10, issue 3, article, pp.267-283) View Online
Abstract:Previous stratigraphical investigations of Romney Marsh have tended to be local in scale, and this has hindered efforts to establish a unifying stratigraphical framework for this area. This paper addresses this problem, by describing the results of a 12-km transect across Romney Marsh, linking previously studied back- and fore-marsh sites (Horsemarsh Sewer and Broomhill respectively), and presenting additional pollen, diatom and radiocarbon data from an intermediate, mid-marsh site (Brookland). One main organic unit is recorded across much of Romney Marsh, although its age, altitude and composition varies. Microfossil and radiocarbon data from Brookland and elsewhere on Romney Marsh show that this organic unit accumulated under a general removal and return of marine conditions that took place between ca. 5100 and 2000 yr BP.
A recently proposed model of barrier development is used to investigate the history of back-barrier sedimentation in Romney and Walland Marshes. This model suggests a three-phase life-history for gravel barriers, which consists of initiation, stability and breakdown. Although there are problems in relating back-barrier deposits directly to barrier dynamics, nevertheless the Romney Marsh data do, for the most part, agree with the expected number and sequence of sea-level tendencies predicted by this model. The back-barrier stratigraphical data suggest that initiation, stability and breakdown of the Dungeness foreland occurred between ca. 6000 and 5000 yr BP, 5000 and 2000 yr BP and 2000 yr BP and present, respectively.
A recently proposed model of barrier development is used to investigate the history of back-barrier sedimentation in Romney and Walland Marshes. This model suggests a three-phase life-history for gravel barriers, which consists of initiation, stability and breakdown. Although there are problems in relating back-barrier deposits directly to barrier dynamics, nevertheless the Romney Marsh data do, for the most part, agree with the expected number and sequence of sea-level tendencies predicted by this model. The back-barrier stratigraphical data suggest that initiation, stability and breakdown of the Dungeness foreland occurred between ca. 6000 and 5000 yr BP, 5000 and 2000 yr BP and 2000 yr BP and present, respectively.
Late Middle Pleistocene deposits at Norton Farm on the West Sussex coastal plain, southern England, by Martin R. Bates and others, published January 2000 in Journal of Quaternary Science (vol. 15, issue 1, article, pp.61-89) accessible at: British Library View Online
Abstract:The coastal plain of West Sussex, southern England, is internationally important because of the sequence of discrete high-sea-level events preserved at various elevations across it. New evidence is presented from a site at Norton Farm, near Chichester, on the Lower Coastal Plain, where Pleistocene marine sands, fining upwards into silts, occur between 5.3 m and 9.1 m OD. The sequence reflects a regressive tendency at the transition from an interglacial to a cold stage. The marine sands have yielded foraminifera, ostracods and molluscs that indicate a declining marine influence through the sequence, culminating in a tidal mudflat, strongly weathered in places. Cool-climate foraminifera (including Elphidium clavatum, Cassidulina reniformis and Elphidium albiumbilicatum) and ostracods have been recovered from the marine sands. Some species with an apparent preference for warmer water conditions, however, are also present. Freshwater taxa washed into the terminal marine sediments include some cold climate indicators, such as Pisidium stewarti and P. obtusale lapponicum. Additional evidence for cool climatic conditions during the deposition of the upper part of the marine sequence is provided by the lack of tree taxa in the pollen record and by features of the micromorphology. The marine sediments probably began accumulating during OIS 7, a conclusion based on their elevation, on amino acid ratios from shells, but especially on vertebrate evidence, particularly the presence of a small form of horse, together with a large, distinctive, form of northern vole (Microtus oeconomus). The occurrence of cool climate indicators in these marine sediments may demonstrate a lag between the climatic deterioration and the expected glacio-eustatic fall in relative sea-level. This evidence appears to support the conclusions drawn from the study of coral terraces in Barbados. Such a scenario would provide the conditions necessary for the emplacement of the large erratic boulders reported from the Lower Coastal Plain of West Sussex.
Vegetation history of the English chalklands: a mid-Holocene pollen sequence from the Caburn, East Sussex, by Martyn P. Waller and Sue Hamilton, published March 2000 in Journal of Quaternary Science (vol. 15, issue 3, article, pp.253-272) View Online
Abstract:A pollen diagram has been produced from the base of the Caburn (East Sussex) that provides a temporally and spatially precise record of vegetation change on the English chalklands during the mid-Holocene (ca. 7100 to ca. 3800 cal. yr BP). During this period the slopes above the site appear to have been well-wooded, with vegetation analogous to modern Fraxinus-Acer-Mercurialis communities in which Tilia was also a prominent constituent. However, scrub and grassland taxa such as Juniperus communis, Cornus sanguinea and Plantago lanceolata are also regularly recorded along with, from ca. 6000 cal. yr BP onwards, species specific to Chalk grassland (e.g. Sanguisorba minor). This supports suggestions that elements of Chalk grassland persisted in lowland England through the Holocene. Such communities are most likely to have occupied the steepest slopes, although the processes that maintained them are unclear. Human interference with vegetation close to the site may have begun as early as ca. 6350 cal. yr BP and initially involved a woodland management practice such as coppicing. From the primary Ulmus decline (ca. 5700 cal. yr BP) onwards, phases of limited clearance accompanied by cereal cultivation occurred. Taxus baccata was an important component of the woodland which regenerated between these phases.
Vegetation history of the English chalklands: a mid-Holocene pollen sequence from the Caburn, East Sussex, by Martyn P. Waller and Sue Hamilton, published March 2000 in Journal of Quaternary Science (vol. 15, issue 3, article, pp.253-272) View Online
Abstract:A pollen diagram has been produced from the base of the Caburn (East Sussex) that provides a temporally and spatially precise record of vegetation change on the English chalklands during the mid-Holocene (ca. 7100 to ca. 3800 cal. yr BP). During this period the slopes above the site appear to have been well-wooded, with vegetation analogous to modern Fraxinus-Acer-Mercurialis communities in which Tilia was also a prominent constituent. However, scrub and grassland taxa such as Juniperus communis, Cornus sanguinea and Plantago lanceolata are also regularly recorded along with, from ca. 6000 cal. yr BP onwards, species specific to Chalk grassland (e.g. Sanguisorba minor). This supports suggestions that elements of Chalk grassland persisted in lowland England through the Holocene. Such communities are most likely to have occupied the steepest slopes, although the processes that maintained them are unclear. Human interference with vegetation close to the site may have begun as early as ca. 6350 cal. yr BP and initially involved a woodland management practice such as coppicing. From the primary Ulmus decline (ca. 5700 cal. yr BP) onwards, phases of limited clearance accompanied by cereal cultivation occurred. Taxus baccata was an important component of the woodland which regenerated between these phases.
River terrace sequences: templates for Quaternary geochronology and marine-terrestrial correlation, by David Bridgland, Darrel Maddy and Martin Bates, published February 2004 in Journal of Quaternary Science (vol. 19, issue 2, article, pp.203-218) View Online
Abstract:Fluvial sequences, particularly terrace staircases, represent archives of Quaternary palaeoclimatic fluctuation and can serve as stratigraphical frameworks for geochronology and for correlation with other depositional environments, in particular, the global marine oxygen isotope record. Fluvial lithostratigraphical frameworks also provide contexts for records, from fossils and artefacts, of faunal evolution and human occupation; conversely, both records can be means of relative dating of riverine sequences.
Three fluvial sequences are examined as case studies. First is the Severn-Avon system in the English Midlands, which has biostratgraphical evidence and an amino acid geochronology, together with marker inputs from three different glaciations. The Somme sequence of northern France, famous for its Palaeolithic artefact assemblages, again has biostratigraphy and an amino acid geochronology and has also been dated with reference to overlying loess/palaeosols sequences. The fluvial terraces of the River Arun, the final case study, lack dating evidence but are interspersed within the Sussex raised beach staircase. Although various lines of evidence suggest that the rivers discussed have formed terraces in response to climatic fluctuation, an intriguing difference is that interglacial sediments occur at the bases of terrace formations in the Severn-Avon, whereas in the Somme they occur at the tops of sequences, beneath loessic overburden. Copyright © 2004 John Wiley & Sons, Ltd.
Three fluvial sequences are examined as case studies. First is the Severn-Avon system in the English Midlands, which has biostratgraphical evidence and an amino acid geochronology, together with marker inputs from three different glaciations. The Somme sequence of northern France, famous for its Palaeolithic artefact assemblages, again has biostratigraphy and an amino acid geochronology and has also been dated with reference to overlying loess/palaeosols sequences. The fluvial terraces of the River Arun, the final case study, lack dating evidence but are interspersed within the Sussex raised beach staircase. Although various lines of evidence suggest that the rivers discussed have formed terraces in response to climatic fluctuation, an intriguing difference is that interglacial sediments occur at the bases of terrace formations in the Severn-Avon, whereas in the Somme they occur at the tops of sequences, beneath loessic overburden. Copyright © 2004 John Wiley & Sons, Ltd.