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The paper continues a complex study of the Santonian–Campanian boundary of the Aksu-Dere and Kudrino-2 sections (Bakhchisarai region, Southwestern Crimea), the sedimentological and biostratigraphic data on which are provided in paper 1. This work presents the paleomagnetic, rock magnetic, and geochemical data on C and O stable isotopes. The 87Sr/86Sr values of limestones increase upward the section: from 0.70741 to 0.70752 in Aksu-Dere and from 0.70750 to 0.70755 in Kudrino-2. On the basis of the results, the outcrops are correlated and the Kudrino–Aksu-Dere composite section is compilled, in which we identified paleontological, paleomagnetic, and isotopic markers necessary for the identification of the Santonian–Campanian boundary. The biostratigraphic boundaries are calibrated against the geomagnetic reversal 34n–33r and the SCBE isotopic event; thus, the base of the Campanian Stage should be determined by the base of the Chron 33r. In the volume of the geological record of the Santonian–Campanian boundary, saturation in guide fossil forms, and complex study, the composite section matches the candidates for a Global Boundary Stratotype Section and Point of the Campanian in North Texas and Southern England. This allows us to propose it as one of the candidates of the stratotype or an auxiliary section of the lower boundary of the Campanian Stage. [ABSTRACT FROM AUTHOR]

This paper examines how non‐marine thrombolites are formed through a complex, multiphase process of microbial framework construction, erosion, cementation, recrystallization and episodes of internal sedimentation. Recognition of such phases of thrombolite construction provides a framework for the interpretation of the fluctuating environmental conditions leading to their formation. Microbialite frameworks are examined in detail from the Purbeck Limestone Group and their affinities and palaeo‐environmental significance assessed. Three types of thrombolite, one stromatolite and a leolite are described and interpreted. The thrombolite frameworks include: a peloidal mesoclotted type, a thrombolite constructed by the filamentous alga Cladophorites and a type with concentrically laminated micritic mesoclots. Physical and chemical erosion led to extensive early cavity formation within the frameworks. Early calcite rim cements with associated spherulites then developed over the microbial frameworks and these were reworked into cavities. Frameworks were also replaced by chalcedonic quartz and calcite spherulites. Internal sediments comprise peloids, intraclasts and brackish‐water molluscs and ostracods, together with their debris. The thrombolites grew in moderate‐energy to high‐energy shallow, lacustrine, microbial mounds whereas stromatolites occurred in deeper‐water settings. A brackish‐water, lacustrine setting is indicated by the preserved macro‐biota, microbes, absence of charophytes and syndepositional evaporites, and negative stable carbon and oxygen isotope ratios. Strontium isotopes suggest that the carbonate‐rich waters were fed from erosion of Mid–Lower Jurassic limestones on the western basin margin with possible mixing with waters from nearby uplifted Upper Jurassic limestones and with Late Jurassic seawater. The research indicates that non‐marine thrombolites have a complex, multiphase origin resulting in a diverse succession of textures and structures relating to microbially induced and influenced construction, dissolution, cementation, recrystallization and mineral replacement which have not been previously recorded and indicate the major differences between marine and non‐marine thrombolites. [ABSTRACT FROM AUTHOR]

Zooarchaeological analysis substantial assemblage of animal bones excavated from Dudley Castle, West Midlands, suggests that a significant change in pig management occurred during the 14th century. A dramatic decrease in the relative abundance of pigs, combined with an increase in the size of post-cranial bones and teeth, and a higher proportion of neonatal individuals, raises the possibility that greater control over breeding and feeding was being exerted in this period through the emergence of enclosed husbandry practices. Carbon and nitrogen stable-isotope analysis of a sample of 41 pig mandibles from two tightly dated phases of occupation supports this interpretation. Between the late 13th century and later 14th century there was a statistically significant decrease in δ15N, but not in δ13C, and pig dietary diversity probably also decreased. This paper discusses several explanations for these patterns, all consistent with a major change in pig management at this time. [ABSTRACT FROM AUTHOR]

Total dissolved inorganic carbon (TDIC) and its stable isotope ratio δ13CTDIC are used to trace the evolution of the carbon system of groundwater in three UK Permo-Triassic sandstone aquifers. Samples were collected from multilevel piezometers, open boreholes and sewer sampling points in the British Midlands (Nottingham, Birmingham and Doncaster) to evaluate both local and regional variations in δ13CTDIC. Δ13C samples of matrix and pore water have also been analysed in each aquifer to further constrain the interpretations. Combining δ13CTDIC ratios with measurements of TDIC and pH clearly distinguishes the principal processes underlying the geochemical evolution of groundwater in Triassic sandstone aquifers, where processes can be both natural (e.g. carbonate dissolution) and anthropogenic (sewer-derived recharge). The paper shows that δ13CTDIC resolves ambiguities that arise from the interpretation of TDIC and pH measurements in isolation. Field measurements demonstrate that, under natural conditions, the carbonate system evolves similarly in each aquifer. An open-system evolution during recharge largely saturates the groundwater with carbonate depending upon its availability in the sandstone matrix. The contribution of sewer exfiltration to urban recharge is readily distinguished by lower pH and higher TDIC values without significant changes in δ13CTDIC. [ABSTRACT FROM AUTHOR]

Abstract: Palaeodietary studies typically focus on the analysis of bone collagen due to the limited availability of plant remains. Isotopic analysis of plant remains, however, allow for a more extensive consideration of the contribution of plants to the human diet and can potentially provide information about the environment in which the crops were grown. This paper reports the results of carbon and nitrogen isotope analyses performed on charred barley and wheat grains recovered from pits within Danebury Iron Age hillfort. To the best of our knowledge, this is the first Iron Age site in Britain from which charred grains have been isotopically analysed. Our results suggest that cereals found at the hillfort were grown in several different environmental contexts. The isotope data demonstrate that the herbivores were not consuming a diet primarily based on grains as the δ15N values of the grains are very similar to those of the herbivores. Palaeodietary investigations typically assume that humans eating plant protein only would have the same δ15N value as the local herbivores. This assumption is clearly invalid at Danebury, where the humans and animals appear to have consumed either different parts of the same plants or different plants. Researchers typically interpret high differences between human and animal δ15N values as indicative of diets high in animal protein, however where major plant resources have δ15N values similar to those of the herbivores our ability to distinguish between plant and animal sources of protein in the diet is limited. Our research has demonstrated that whenever possible it is desirable to measure the isotopic signatures of potential major plant resources in order to understand past subsistence strategies. [Copyright &y& Elsevier]

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Mount Sandel has long been an iconic site for the Irish Mesolithic, having produced evidence for a sequence of occupation huts and pits and the earliest radiocarbon dates for the Mesolithic on the island. This paper presents details of a recent programme of redating whereby the application of Bayesian modelling has confirmed the early date for the site but also helped to refine its internal chronology. The major phase of hut building at Mount Sandel took place within a much shorter period of time than had previously been thought, perhaps only a generation or two. The dating of pits of differing sizes suggests that many of them were created during other slightly later visits to the area. The implications of the dating programme for the place of Mount Sandel in the Irish Mesolithic, and for the chronology of the period and its relations with that on the British mainland, are discussed. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a case study aimed at correlating archaeological ‘events’ (obtained from radiocarbon measurements and dendrochronology) from the site of Sutton Common with a radiocarbon-dated pollen sequence obtained from a palaeochannel deposit adjacent to the area of the main archaeological activity. It demonstrates the use of a Bayesian approach to quantifying whether the timing of palynological ‘events’ interpreted as reflecting anthropogenic impacts are likely to be associated with archaeological ‘events’. The results suggest that Bronze Age activity in the form of a mortuary enclosure and associated cremation burials are probably not contemporary with the palynological evidence for disturbance to the oak–hazel woodland in this period. Subsequent evidence for local woodland clearance and agriculture is estimated to precede the construction of the large Iron Age enclosure in 372 BC, with increases in ‘anthropogenic indicators’ following this ‘event’. The construction of the site does not appear to have had a pronounced impact on the local vegetation, with hazel the only woody taxon to show clear reductions. Despite the use of a substantial number of oak timbers in the enclosure palisade, percentages of oak remain remarkably stable. Later farming activity on the site probably post-dates the end of activity in the enclosures. The value of the methodology is discussed in relation to quantifiable and robust correlations of archaeological and palaeoenvironmental narratives of landscape and human activity. [Copyright &y& Elsevier]

Archaeology has yet to capitalise on the opportunities offered by bioarchaeological approaches to examine the impact of the 11th-century AD Norman Conquest of England. This study utilises an integrated multiproxy analytical approach to identify and explain changes and continuities in diet and foodways between the 10th and 13th centuries in the city of Oxford, UK. The integration of organic residue analysis of ceramics, carbon (δ13C) and nitrogen (δ15N) isotope analysis of human and animal bones, incremental analysis of δ13C and δ15N from human tooth dentine and palaeopathological analysis of human skeletal remains has revealed a broad pattern of increasing intensification and marketisation across various areas of economic practice, with a much lesser and more short-term impact of the Conquest on everyday lifestyles than is suggested by documentary sources. Nonetheless, isotope data indicate short-term periods of instability, particularly food insecurity, did impact individuals. Evidence of preferences for certain foodstuffs and cooking techniques documented among the elite classes were also observed among lower-status townspeople, suggesting that Anglo-Norman fashions could be adopted across the social spectrum. This study demonstrates the potential for future archaeological research to generate more nuanced understanding of the cultural impact of the Norman Conquest of England, while showcasing a method which can be used to elucidate the undocumented, everyday implications of other large-scale political events on non-elites. [ABSTRACT FROM AUTHOR]

This article focuses on an ancient fragment of a maxilla in Torquay Museum at Devon, England, which could be the oldest example from a modern human yet found in Europe. The bone, which has been in the museum for the past 80 years, was excavated by the Torquay Natural History Society in 1927 from Kent's Cavern, and has only three teeth. The maxilla is currently the oldest dated fragment of a modern human in Great Britain and the second oldest in Europe. Radiocarbon dating had previously dated it to about 31,000 years ago, but now scientists have discovered that it is more than 6,000 years older than previously thought. Roger Jacobi of the British Museum, and Tom Higham from the Oxford Radiocarbon Accelerator Unit found that the jawbone had been strengthened by the addition of paper glue probably sometime soon after discovery, thus contaminating the specimen and making its current radiocarbon age of 31,000 years ago suspect.

The recent discovery of one of the earliest Mesolithic occupation sites in northern Britain, at Howick on the Northumberland coast, in association with multiperiod archaeological evidence nearby, highlights the importance of UK coastal settings as focii of human occupation through the Holocene. Environmental evidence from a nearby river valley (8.15 m of sediment ranging in age from about 12 000 cal. BP to the present) records local and regional environmental change. Twenty-four radiocarbon dates based on plant macrofossils provide a strong chronological framework. Calcareous microfossil assemblages (foraminifera, ostracods) have been recovered from the fine-grained sediments, recording a change from marine through to brackish and eventually freshwater conditions between about 8200 and 6500 cal. BP. A preliminary pollen study of the core has permitted a reconstruction of the regional vegetation as it responded to climatic amelioration and human influence upon the landscape. Radiocarbon dating and sedimentological evidence indicates a major hiatus between approximately 11 000 and 8000 years BP (including the period of Mesolithic occupation), represented by a 30 cm layer of coarse sands and sandstone pebbles, probably the result of a significant high-energy event dated to about 8300 cal. BP. Although not a typical tsunami deposit, the age and context suggests that this may be associated with the Storegga Slide event, already well-documented along the eastern coast of Scotland. The sedimentary and biological remains at Howick record environmental change over much of the Holocene and are compared with other environmental change records from the region to provide an environmental framework for the archaeology of this coastline. [ABSTRACT FROM AUTHOR]

Marine/brackish clastic sediments replace freshwater peats in the stratigraphic column of many coastal lowland areas bordering the North Sea during the late Holocene. Radiocarbon dates are routinely used to provide a chronology for this shift. We examine the assumptions underpinning this approach. The results of investigations from 13 sites in the Rye area of Romney Marsh, southeast England, are reported. Dates from apparently gradational contacts of a highly humified, laterally persistent, peat layer range from 3170–2840 cal. yr BP to 1290–1050 cal. yr BP. Multiple inundations or prolonged gradual inundation are nevertheless rejected, as discrete post-peat bodies of sediment are absent and because peat growth appears to have slowed-down or ceased at many sites in advance of inundation. Additionally in the Rye area, sharp contacts are widespread and the pollen assemblages rarely indicate the occurrence of transitional plant communities. A review of the dating evidence from other coastal lowland regions reveals that multiple dating of the upper surface of peat beds invariably produces diachronous results. As a consequence time-transgressive processes feature prominently as causal mechanisms underlying this shift. However, many of the dating difficulties recognized in the Rye area appear to apply to other regions. We conclude that radiocarbon dates from the upper surface of peat layers should in most instances only be regarded as limiting ages for the deposition of the overlying clastic sediments. New chronologies need to be built without a priori assumptions as to the underlying processes, ideally through the direct dating of the clastic sediments. [ABSTRACT FROM AUTHOR]