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141.
Recently, two problems have been recognized with the United States Southwest archaeomagnetic master curve (Eighmy, 1991; LaBelle & Eighmy, 1997; Sternberg, 1989). One of these problems, the damping problem, is inherent to the moving window method of curve construction proposed by Sternberg (1989). The other is due to the fact that the small number of independently dated virtual geomagnetic pole determinations available for the period between 900–1100 are not representative of secular variation during this period. The analyses presented here confirm the existence of these two problems and suggest that they distort the curve by less than 1·0° and between 1·0° and 2·0° respectively. Based on these findings, a new curve is proposed for the U.S. Southwest.  相似文献   
142.
The characterization of a ceremonial bronze axe is described. The axe is assigned to the Santamarian culture of north‐west Argentina, c. 1000–1470 ad, and was selected to increase presently limited knowledge of prehistoric metallurgy in the Andean region of Argentina. The characterization methods used were electron probe microanalysis, gamma radiography, X‐ray diffraction, optical metallography and microhardness testing. The axe was well cast in a bivalve mould, with the only defects in the area of an ancient fracture. The analysis showed that it is made from a tin bronze with a, probably, accidental addition of lead. Arsenic was found as a surface contamination, probably deriving from arsenic in the water of the stream in which the axe was found. The axe shows that Santamarian craftsmen had the skill to decorate the axe in an artistic style with a strong local accent while providing a functional, annealed and cold‐worked cutting edge.  相似文献   
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Biocultural patterns surrounding the emergence of agriculture from 11 sites in the central Tombigbee River valley (500–1200 AD), 50–100 km west of the emerging Moundville polity, suggest that while food production may have alleviated some ecological stress, it came at a cost. Markers of childhood arrest indicate earlier weaning, likely creating a cycle of rising fertility and competition, but surviving adults appear better off following intensification. Health disparities at farmsteads, including more prevalent anemia, growth defects, lower limb infections, and accidental trauma, are consistent with increasingly competing demands of domestic and corporate modes of production. Although these agricultural settlements in the hinterlands were not severely compromised as predicted by a strictly top down model of provisioning, health risks assumed by farmsteads may have resulted from provisioning to centers and/or corporate lineages while simultaneously mitigating larger risks (e.g., raiding). The greater health risks assumed by farmstead females suggest that they had less control over production and decision-making than women buried at centers, while height and upper body strength at mound centers, in addition to rare but extreme trauma, point to identities that were mapped not only onto the landscape, but onto the bodies of men and women occupying elite spaces.  相似文献   
146.
Determination of the source of Spondylus objects is essential for the interpretation of Late Neolithic exchange systems and the social role of shell ornaments. We performed stable isotope analysis combined with cathodoluminescence microscopy study on ornaments (beads, bracelets) made of Spondylus shells excavated at the Aszód-Papi földek archaeological site in Hungary, to define their origin. For comparison Spondylus finds from Neolithic sites of Greece, modern Spondylus shells from the Aegean and the Adriatic, as well as fossil Spondylus and Ostrea shells from the Carpathian Basin were also examined. Oxygen isotope composition of Spondylus finds from Aszód ranges between ?1.9 and 2.1‰ and overlaps with the oxygen isotope range of shell objects from other Neolithic sites. Modern Spondylus shells from the Aegean and the Adriatic show overlapping δ18O values with one another and with the Neolithic objects; while recent shells of the Black Sea clearly are separate isotopically from the Mediterranean ones and most of archaeological artefacts. Spondylus shells from the Aszód site have Mediterranean origin; their source can be the Aegean or the Adriatic. Based on a former strontium isotope study the use of fossil Spondylus shells is excluded as raw material used for ornaments, however, in recent years the use of fossil shells was reintroduced. The shell ornaments from Aszód-Papi földek and the fossil oyster shells collected from the Carpathian Basin exhibit some overlapping oxygen isotope values; however, cathodoluminescence microscopy indicates that the Spondylus objects retained their original aragonite material. Diagenetic calcite, which occurs typically in the fossil shells, was not detected in the ornaments suggesting that the studied objects were made of recent shells. Calcitic parts observed in some Spondylus objects are not related to fossilisation.  相似文献   
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3D surveys of archaeological elements and the construction of virtual models enable us to reconstruct historical sites. They provide useful data to select specific building processes.Photogrammetry and Terrestrial Laser Scanning (TLS) are the most common techniques to obtain synthetically heritage models. These techniques provide massive data which can only be managed by replacing them by primitive shapes, thereby obtaining more simple models and the explicit geometry of the element. Statistical and robust methods are used for this substitution, thereby avoiding the common errors due to measuring. Of these methods, the most widely used are the least-median-of-squares (LMedS) and the RANSAC method.Another computation method consists in recursive processes based on evolutive-type algorithms to adjust the model to the data captured.This paper describes two surface computation methodologies to determine the modelling of a column shaft located in temple G of the archaeological park of Selinunte (Sicily).  相似文献   
149.
The sufferings of French non-combatants, particularly peasants, during the Hundred Years War have been described and deplored from the fourteenth century to the twentieth. A concern for the victims has often left little room for a careful study of the aggressors, thepillars andbrigands of the contemporary records. This article seeks to identify these latter, to distinguish them from each other and from the noble warriors, often called ‘men-at-arms’. It will be shown that the first, brutal, contact between armed men and unarmed ‘civilians’ was not, as the contemporary moralists suggested, between noble and non-noble, but between non-noble and non-noble: between common soldiers and bandits, on the one hand, and peasant victims, on the other. The chivalrous and adventurous war of knights and squires was sustained on the day-to-day level, by the activity of foraging pillagers. Brigandage was a consequence of their activity, not another name for it.  相似文献   
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