1,721,032 research outputs found
Windermere Multibeam Bathymetry Data
No full textMultibeam Bathymetry Data was collected by the British Geological Survey in September 2010 in association with the University of Southampton in both the north and south basins of Windermere in the English Lake District. Data was analysed by Helen Miller and Jonathan Bull from the University of Southampton as well as Carol Cotterill from the British Geological Survey. The data is freely available for download and it would be appropriate to cite the following reference when using the data:
Miller, Helen, Bull, Jonathan M., Cotterill, Carol J., Dix, Justin K., Winfield, Ian J., Kemp, Alan E.S. and Pearce, Richard B. (2013) Lake bed geomorphology and sedimentary processes in glacial lake Windermere, UK. Journal of Maps, 9, (2), 299-312. (doi:10.1080/17445647.2013.780986).
The data is not appropriate for navigational use.
Further information on the survey is available at:
http://www.bgs.ac.uk/research/highlights/2013/lakeWindermere.html
A pdf map of the multibeam data is available for download, and the data can be downloaded here at 1 m and 5 m resolutions from the north and south basins of Windermere.</span
The Relic Palaeo-landscapes of the Thames Estuary
No full textA geological and heritage assessment of the Outer Thames Estuary as part of an MALSF-MEPF Regional Environmental Characterisation project revealed c.15,000 km2 of palaeo-landscapes hypothesised as dating from 600,000 to 720,000 years ago. These deposits lie immediately offshore from the region that has produced the earliest archaeological evidence for the occupation of the British Isles (c. 600,000 to 700,000 years ago). The exceptional level of preservation of this landscape holds great potential for: understanding our earliest archaeological heritage; understanding the broader geological changes which have occurred during several episodes of sea level change; and providing an enhanced context for a number of aggregate licensing areas and other commercial seabed projects. To resolve the true importance of this landscape this, one year, follow-on project aimed to improve the chronology of this very important submerged landscape. In order to establish the chronology of this area the project aimed to collect 30 (<6 m) long vibrocores from carefully chosen locations distributed across this landscape. These sites were identified from the interpretation of new and legacy seismic data collected during the project and provided by the aggregate industry (Resource Management Association). The retrieved sediments would be logged and appropriate materials selected for analysis by a combination of dating techniques (palaeo-secular variation (PSV), amino acid racemization (AAR), electron spin resonance (ESR), optically stimulated luminescence (OSL) and radiocarbon dating.Over the twelve months of the project: fifty-five square kilometres of swath bathymetry data and co-registered backscatter have been acquired; a further thirty square kilometres of swath bathymetry has been provided by the Harwich Harbour Authority; twenty-five line kilometres of boomer data from the main palaeo-river channel in the area has been acquired; and finally several hundred line kilometres of extant boomer data and a total of 133 borehole logs and photo imagery have been provided by the Resource Management Association. These datasets were fully processed and integrated with data acquired during the initial REC project to provide a three phase model of landscape evolution. The proposed thirty vibrocores were successfully acquired giving a total of 140 m of sedimentary core, an intact archive of which now resides in the BOSCOR facility at the NOCS. These cores have been fully logged, photographed and analysed for grain size. In turn, these lithological data sets have been correlated with the appropriate seismic sections to further enhance a geological model of the area. In addition, we have undertaken extensive sampling and analysis of the cores, for PSV, AAR, ESR, OSL and radiocarbon dating to build up a chronological picture of the development of the submerged landscapes of the Outer Thames Estuary.The sampled sedimentary sequences are dominated by Late Glacial to mid- Holocene sediments deposited since the Last Glacial Maximum c. 20,000 years ago. However, the project has provided significant evidence to support the original hypothesis of a much longer term evolution of this river system, which can be split into two distinct phases. Firstly, there is a record of river channel activity across the area in the Middle to Late Pleistocene (c. 160,000 – 70,000 years ago) and secondly, from a more restricted number of sites we have identified both morphological and dating evidence to support our original hypothesis of a landscape that potentially dates back to the early Middle Pleistocene (significantly older than 420,000 years ago).This intensive project has successfully accomplished all that it set out to do in the tight time frame and in addition to the immediate results will provide a platform for more intense study over the next year, where additional dating will be undertaken; more detailed analysis of the environmental information in the cores will be done; and integration with the extensive but sparsely distributed onshore record can be made
The Solutrean Atlantic Hypothesis: a view from the ocean
No full textOne current hypothesis for the Pleistocene peopling of the Americas invokes a dispersal by European hunter-gatherers along a biologically productive "corridor" situated on the edge of the sea-ice that filled the Atlantic Ocean during the Last Glacial Maximum (LGM). In this paper, we assert that critical palaeoceanographic data underpinning this hypothesis has not yet been examined in sufficient detail. To this end, we present data which show that the corridor may not have existed, and that, if it did, its suitability as a migration route is highly questionable. In addition to demonstrating that the hypothesized migration was unlikely, this highlights the importance of integrating palaeoceanographic and archaeological data in studies of palaeo-coastal societies
Fish infection and disease in a changing world: Implications for fish resilience and food security
Full text linkFish infection and disease in a changing world: Implications for fish resilience and food security
Simulating mass loss of decaying waterlogged wood: A technique for studying ultrasound propagation velocity in waterlogged archaeological wood
No full textOften cultural conservators are asked to assess the preservation state of waterlogged wooden artefacts whose identity and rarity place an ethical barrier on the use of destructive analysis techniques. In addition, conservators are continually being challenged to find new ways of assessing the preservation of the underwater heritage, such as wooden shipwrecks, whilst in situ, and thus assist the process of managing such sensitive archaeological sites. Ultrasound compressional (p-) wave velocity has been researched in the past as a potential tool for estimating the preservation state of wooden artefacts and timbers. Its non-invasive principal complies with conservators’ working ethics, while it has shown the potential of mapping and imaging submerged wooden archaeological heritage objects, as well as estimating the in situ preservation state. The aims of this paper are to present a viable non-destructive assessment method for cultural conservators for working on laboratory samples of waterlogged wood and to provide data for the analysis of in situ sites. This paper outlines the approach for the preparation of samples; the generation of controlled test-pieces for systematically quantitatively assessing the relationship between mass loss expressed as basic density and p-wave measurements; acoustic measurement; and the initial empirical results. Mass loss is achieved in a controlled and reproducible way for testing with ultrasound. The process incorporates a set of increasing wood degradation levels by gradually removing wood mass from waterlogged oak and pine test-pieces via drilling holes along the grain (longitudinal wood growth axis). This is followed by a chemical treatment with alkaline of the fully drilled wood test-pieces. The same test-pieces are used from zero to maximum degradation. This allows consistent observations, restricts variability and enhances interpretation of the results. The study considers wood both as a raw material and an artefact, here exemplified as the hull components of ancient wooden ships. Dimensions and cutting orientations of the test-pieces respect those noted in archaeological records. The focus is set on the RL and TL planes (radial and tangential axis respectively) and TL (tangential axis) planes, the main planes expected to be insonified with ultrasound considering timber conversion techniques in ancient shipbuilding. Ultrasound testing is performed within a reinforced polyethylene water tank, with the wood test-piece placed in between the transmitter and the receiver in good alignment. Using the trough-transmission immersion technique the time it takes a p-wave to travel through the test-piece together with the latter's thickness, are used to calculate the propagation velocity. Results demonstrate that ultrasound waves travel faster in the radial than in the tangential direction; although advancing the degradation, wood becomes more isotropic across the grain as indicated by the reduction of VRadial/VTangential ratio. Ultrasound velocity is unaffected by the structural differences between ring-porous oak and pine allowing quantitative results for a density range between 0.567 gcm−3 (fresh) and 0.292 gcm−3 (degraded) irrespective of wood species used. Two significant empirically derived equations can be used by the cultural conservator to derive a wood density level, a common bench mark for assessing archaeological wood degradation level.</p
The Outer Thames Estuary Regional Environmental Characterisation
No full textThe Outer Thames Estuary Regional Environmental Characterisation (REC) provides an environmental reference statement defining marine and seabed conditions within the study area. Prior to this study, regional environmental assessment of the Outer Thames Estuary was based upon dispersed data acquired over several decades. The Marine Aggregate Levy Sustainability Fund (MALSF) has provided the opportunity to acquire and interpret an integrated physical and biological dataset for the first time in this region. The dataset was acquired along geophysical survey transects spaced 10 – 20 km apart and grab samples were recovered at the intersection of survey lines. The Outer Thames Estuary REC provides a unique, robust scientific basis to define the regional marine environment, outlining the character of seabed conditions in the study area. This will permit informed, confident and consistent decision-making and consequently the Outer Thames Estuary REC will be of value to all stakeholders including government, marine industry, planners and environmentalists. The knowledge will contribute to the protection of the marine environment, promote the sustainable management of the seabed and focus future development investment. The Outer Thames Estuary REC develops the approach initially adopted in previous marine aggregate regional characterisation studies but also makes a comprehensive assessment of the heritage issues. The characterisation process begins by reviewing the physical conditions in the area, for example tides, currents, seabed geology and seabed sediment transport. The heritage assessment has been combined with the interpretation of the Quaternary geology to produce an integrated assessment, whilst the wreck and other modern archaeology are treated separately. Analysis of the benthic infauna and epifauna communities is combined with an evaluation of their associated physical conditions to produce a habitat and biotope assessment. The principle characterisation is supplemented with high-level summaries of marine mammals, birds and anthropogenic activities for context. The characterisation process also highlights regional environmental sensitivities, for example sites of potential conservation, fisheries or heritage significance, as well as informing marine spatial planning. Geology and Heritage The seabed consists of three distinct morphological zones. The Western Zone is dominated by a large coast-parallel sandbank system. The sandbanks are composed of well sorted fine-medium grained sand whilst sandy gravels lie on the seabed in the troughs between the banks. The Central Zone consists of a bedrock platform typically overlain by a discontinuous, thin, gravelly lag deposit, dispersed sandy bedforms and isolated sandbanks. Two parallel, north-south trending troughs, the Inner Gabbard Deeps, have been eroded into the bedrock in this zone. The seabed in the Eastern Zone consists of an extensive sand dune field. In general there is a net seabed sediment transport to the south across the area. The Outer Thames Estuary REC survey has revealed a geological and archaeological record of previously unquantified significance. The combined interpretation of bathymetry of varying resolutions, sub-bottom data, a limited amount of core and grab material and a full review of the extant geological and archaeological record, has achieved a significantly enhanced interpretation of the Outer Thames Estuary. Of central importance is the identification of c. 1,500 km2 of submerged palaeo-landscape dating from c. 720,000 BP. This represents a significant feature of both geological and archaeological interest. The seabed in the Outer Thames Estuary mainly comprises a thin, superficial layer of mobile and immobile sediments overlying exposures of Quaternary, Cenozoic and Cretaceous sediments. Ten enclosed deeps are identified and interpreted as being formed at the margin of the Elsterian-Anglian glacial maximum ice limit. The stratigraphic relationship of these features with the major eastwest river system (the Thames-Medway) that cuts across the Outer Thames Estuary REC area suggests this channel must have been incised prior to this glaciation (Oxygen Isotope Stage (OIS) 12: c. 450 kaBP). Further, the spatial correlation of this channel system with terrestrial river terrace gravels on the Essex coast suggests it may have been formed as early as Cromerian Complex II (OIS 18: c. 720 kaBP), but at least by OIS 15 (c. 600 kaBP). The southern edge of the Outer Thames Estuary REC area does cross the northern margin of the post-Elsterian/Anglian Thames-Medway river courses as they migrate southwards and separate to become the modern Thames and Medway systems. Again, through spatial correlation with the terrestrial record, c. 40 m thick sections of river channel infill sediments have been identified, which may hold a record of 450,000 years of sedimentation. The Outer Thames Estuary REC study reveals a potentially highly significant record from an archaeological perspective. There are two broad categories of submerged archaeological material that may potentially exist within the Outer Thames Estuary REC area: shipwreck sites and terrestrially deposited archaeological material subsequently inundated by rising sea levels. In terms of the wreck record 1,576 individual incidents are documented for the area, with an additional seven anomalies identified as a part of the characterisation process. The wrecks for which details were available date from between AD 1320 – 2005, and range in type from fishing vessels, through submarines, to second world war aircraft. Available survey data only covered a small proportion of the total area considered, and as such the location of only c. 6% of wrecks recorded in the UKHO could be verified. With regard to submerged terrestrially deposited archaeology, the Outer Thames Estuary REC area parallels one of the most important stretches of coastline for Palaeolithic archaeology in the British Isles. Bracketed by the key internationally significant Lower Palaeolithic sites of Clacton (to the south) and Pakefield (to the north), the coastline in this region has produced evidence for the earliest occupation of the British Isles at c. 600 – 700,000 BP. As such, the determination of a large area of submerged landscape dating from 720,000 BP offshore of these sites is deemed to be highly significant and worthy of future investigation to evaluate its potential. This determination is based on the value of this landscape as a resource to inform about the broader changes which occurred through the Pleistocene and into the Holocene, as much as the possibility for preservation of primary and secondary context archaeological material. In addition, there is a third class of archaeological material found within the survey area; the modern terrestrial feature of Walton-on-the Naze Pier which extends c. 17 m into the Outer Thames Estuary REC. This is a significant local feature and forms part of a conservation area
Of mammoths and other monsters: historic approaches to the submerged Palaeolithic
No full textRecent research on the submerged central and southern North Sea basin has focused on the end of the story, the last few millennia before the final inundation. Much older deposits do survive, however, and are documented by collections of Pleistocene fauna recovered by fishing fleets operating from Dutch and British ports during the nineteenth and early twentieth centuries. Analysis of the British collections allows them to be assigned to specific areas of seabed and to broad stages of the Pleistocene climatic sequence. The results provide evidence of more complex and fragmentary undersea landscapes than can be detected using geophysical approaches alone, and indicate targeted areas for future work
Strategic Support for Marine Development Management: Palaeolithic archaeology and landscape reconstruction offshore
No full textThe beach replenishment programme from Clacton-on-Sea to Holland-on-Sea, Essex, carried out between 2014 and 2015, has resulted in the appearance and collection of both Pleistocene mammalian remains and stone tools, including Early Middle Palaeolithic Levallois; one of the largest in the country (Scott pers. comm.). The sands used in this coastal protection scheme derived from offshore Licence Area 447. As such, this raised questions surrounding the measures of mitigation that had been in place for Area 447, the subsequent beach replenishment programme during the marine licence application stage, and the potential to recover information from pre-existing, split-open vibrocores. Due to these concerns, Historic England commissioned the University of Southampton (Project 7738, led by Dr Rachel Bynoe) to assess the existing datasets available for Area 447 to permit the reconstruction of a narrative around the formation of the archaeological deposits extracted from Area 447 and their subsequent use, which would in turn help understand why the industry methodologies used at the tim
Coastal environments and their role in prehistoric migrations
No full textIn recent years, increased attention has been turned towards the role of coastal environments in facilitating the global dispersal of humans. Previous approaches have focused on locating, dating and linking coastal archaeological sites, in order to create an overall impression of population movement across continents. When considerations of the actual process of colonization have been presented, they have been predicated on a series of assumptions regarding the nature of the coastal environment. The most important of these is that the coastal zone is homogenous and stable, on space and time scales relevant to human migration. This paper aims to test this and other assumptions by considering the true nature of the palaeo-coastal zone on global to continental scales and on timescales commensurate with migrating populations. Evidence is presented from Pleistocene and Holocene palaeo-environmental and archaeological records, so covering the major migrations of the Palaeolithic and Mesolithic. The principal conclusion of this study is that the coastal zone is in fact characterized by a significant degree of environmental heterogeneity and instability on a multitude of spatio-temporal scales. This in turn has significant implications for how we interpret the actual process of colonization.<br/
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