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101.
Erwan Messager Aïcha Badou François Fröhlich Brigitte Deniaux David Lordkipanidze Pierre Voinchet 《Archaeological and Anthropological Sciences》2010,2(1):25-34
Mineralised fruits and seeds are frequently found in archaeological sediments but their chemical nature has not been often
examined. The nature and the origin of these archaeobotanical remains have to be investigated to understand their taphonomic
history. Fruits or seeds can be mineralised not only by replacement mineralisation but also by biomineralisation during the
plant life. The mineral components of three fossil fruits sampled on the Pleistocene site of Dmanisi were analysed and compared
with their modern analogues. Analyses were carried out by means of an environmental scanning electron microscope, equipped
with an energy dispersive X-ray device and by means of a Fourier transform infrared spectrometer. Biogenic carbonates and/or
biogenic silica were identified in the fossil and modern fruits of some taxa. Comparison between fossil and modern specimens
has shown that molecular reorganisation occurred in carbonate and in biogenic silica during fossilisation, through diagenetic
processes. The resulting stable mineral structures confer an exceptional preservation to fruits in sediments. Taking into
account these taphonomic specificities (transformation and differential preservation), the chronological and palaeoenvironmental
aspects of the mineralised fruits are discussed. 相似文献
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Ruth M.K. Plets Justin K. Dix Jon R. Adams Jonathan M. Bull Timothy J. Henstock Martin Gutowski Angus I. Best 《Journal of archaeological science》2009
The remains of Henry V's flagship, the Grace Dieu, currently lie buried within the inter-tidal sediments of the River Hamble (S. England). Previous archaeological investigations have been hindered by difficult excavation conditions resulting in a poor understanding of the dimensions, shape and degradation state of the hull's deeper structure. This study therefore aimed to image, characterize and reconstruct the buried remains of this vessel using a high-resolution 3D acoustic sub-bottom Chirp system with RTK-GPS positioning capability. The accurate navigation and high-resolution data that were acquired enabled the construction of a full 3D image of the site that not only identified the remains of the wooden hull, but also features buried within it. In addition, the degradation state of these buried wooden remains were investigated by calculating reflection coefficients while a hypothetical larger reconstruction of the Grace Dieu's hull was achieved, through the use of the ShipShape ship design software package. 相似文献
107.
El'ad N. Caspi Hanania Ettedgui Oleg Rivin Martin Peilstcker Beni Breitman Izhak Hershko Sana Shilstein Sariel Shalev 《Journal of archaeological science》2009,36(12):2835-2840
Neutron diffraction (ND) analyses of ancient metals show that this method is capable of detecting differences in the inner composition and microstructure of ancient metal objects. Here, ND measurements were conducted on two ‘eye shaped’ axes from the end of the 3rd-beginning of the 2nd millennium BC. The objects were excavated from the ancient cemetery of ‘Enot Shuni' Israel; one is made of bronze and the other of silver. Both artefacts are rare finds, with the silver axe unique in the archaeology of Israel, and therefore had to be analysed locally. For that purpose, a newly assembled diffractometer (KARL) at the IRR-1 of the Nuclear Research Centre (Soreq, Israel) was used. ND measurement on the bronze axe revealed the existence of an α-phase with a range of Cu/Sn ratios (Cu–Sn solid solutions) and some amount of a δ-phase (intermetallic compound of Cu and Sn). The silver axe ND pattern shows the existence of an α-phase (Ag–Cu solid solution) and some amount of copper metal. Our ND data are discussed in comparison with XRF surface measurements and thermal neutron radiography. The results are shedding more light on the in-depth material composition profile, as well as on the objects’ structural and compositional affinities, and help to better understand the production processes and assist in conservation decisions. 相似文献
108.
Brian S. Robinson George L. Jacobson Martin G. Yates Arthur E. Spiess Ellen R. Cowie 《Journal of archaeological science》2009,36(10):2184-2191
A paucity of archaeological remains of Atlantic salmon in Northeast North America has been cited as evidence that the species may have been present in the region only during and after the Little Ice Age (ca. 1450–1850 AD), one of coldest periods of the Holocene. However, significant problems of preservation, recovery and identification remain. Here, improved methods of identification use vertebra structure to distinguish salmon from trout, and strontium/calcium ratios to differentiate sea-run from landlocked salmon. In addition to the Little Ice Age, Atlantic salmon is identified in tightly dated contexts at 7000–6500 and 3500–3000 calendar years BP, during climate periods that were comparatively warm and wet. 相似文献
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