The application of a new method of Fourier Transform Infrared Spectroscopy to the analysis of burned bone

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Experimental abrasion of water submerged bone: The influence of bombardment by different sediment classes on microabrasion rate

Data presented here demonstrates the utility of quantitative analysis of sediment-induced microabrasion on bone's surface. Fresh sheep (Ovis aries) bone, acting as a human analogue, was bombarded by mobile sediments from silt, sand and gravel classes (ranging 20 μm–3.35 mm) in a series of flume-based experiments. Controlled bombardment produced unique abrasion patterns on bone which were recordable using scanning electron microscopy. Imaging abrasion at both × 100 and × 1000 magnifications allowed quantitative and qualitative distinction to be made concerning the sediment class that the bone was abraded by; bombardment by gravel classes caused abrasion to advance through cyclical cracking, whereas smoothing of bone's surface occurred more frequently in sand and silt classes. A stepwise multi-linear regression model identified changes in sediment grain size (p < 0.001), duration of exposure to abrasion (p < 0.001), sphericity of the abrasive (p = 0.002), and T value (abrasive force) (p = 0.013) respectively, as the strongest rate limiting factors controlling microabrasion propagation. The methodology presented herein demonstrates analytical value by allowing diagnostic modifications to bone's surface to be correlated with specific taphonomic processes. Data developed from flume-based experimentation was applied in four separate case studies; abrasion data recorded on bones recovered from different aquatic contexts, was linked to hydrological and marine seabed sediment data to demonstrate how documented microabrasion can reflect the different sedimentary contexts bone has passed through. In light of these results we suggest that a quantitative approach to analysing abrasion on bone retrieved from water has potential to allow remains' submersion times and transport pathways to be established with a higher degree of resolution than is currently possible. The development of improved methodologies for the interpretation of submerged human bone is vital due to the increasing risks posed by flooding and coastal erosion to archaeological sites

The abrasion of modern and archaeological bone by mobile sediments: the importance of transport modes

Fresh, weathered, archaeological and fossilized bones were subjected to a series of abrasion experiments using fine sand in an annular flume in order to link bone-surface abrasion to flow regimes and sediment transport modes, compare these effects on bones of different states, and quantify the extent and types of wear occurring. Flow velocities were chosen to replicate the predominant transport modes of bedload, saltation and suspension.Comparative scanning electron microscopic image analysis was performed to assess the degree and type of wear occurring on each bone type for the different transport modes over a range of exposure periods from 24 to 72 h.These preliminary investigations have shown that both the amount and type of wear experienced was related to the bone type, duration of exposure and the mode of sediment transport with wear being the result of deformation, rather than cutting wear.The formation of scour pits in the sand bed on the upstream side of the bone samples significantly reduced wear, and appears to be an important control mechanism for impact related wear that has been overlooked until now

Death on the frontier: military cremation practices in the north of Roman Britain

The study of cremated human remains from archaeological contexts has traditionally been viewed as less valuable than the study of inhumed bodies. However, recent methodological and theoretical developments regarding the taphonomic processes that transform the human body during cremation have highlighted their potential for understanding past cultural and funerary practices. This study combines the first application of spectroscopic with more traditional methods of studying cremated bone to examine Romano-British contexts, with the aim of better understanding funerary practices along the military frontier. Five Romano-British military sites from northern England (Beckfoot, Carlisle, Herd Hill, Lincoln and Malton) were studied, with remains excavated from a range of cinerary urn contexts. Despite the known heterogeneity of the ethnic composition of the Roman army, analyses revealed a surprising consistency with respect to the cremation practice, implying shared knowledge of pyre procedure and, possibly, a prescribed funerary practice amongst military communities in the Roman North. The consistency within these five northern provincial sites in Britain stands in contrast to cremation contexts from Roman sites elsewhere in Europe, as well as other periods of the British past. The associated material culture recovered from these cremation deposits, however, does provide evidence for differences in dress and bodily display. This contrasts with the homogeneity of the cremation technology and highlights the importance of these individualizing features for signalling identity amongst Roman military communities in Britain

Implications of heat-induced changes in bone on the interpretation of funerary behaviour and practice

Bones submitted to heat experience structural and chromatic modifications. In particular, heat-induced bone warping and thumbnail fractures have been linked to the burning of fleshed and green bones where the soft tissues have been removed from the bones soon after death e in contrast to dry bones. Those have been suggested as indicators of the state of the individual before being burned thus allowing inferences about the funerary behaviour of archaeological populations. A large sample of 61 skeletons submitted to cremation has been examined for the presence of both of these heat-induced features. Although uncommon, bone warping and thumbnail fractures were present in some of the skeletons demonstrating that its presence is not restricted to the burning of non-dried bones as generally believed. Rather than being an indicator of the presence of bones with soft tissues, bone warping seems to be more of an indicator of the preservation of collageneapatite links which can be maintained on dry bones with low collagen deterioration. In addition, our results also do not confirm thumbnail fractures as an exclusive sign of the burning of bones with soft tissues. As a result, these heat-induced changes should be used with caution when trying to infer about the pre-burning state of an individual.FC