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31.
This study presents the first ever lead isotope ratio data for copper ore samples (malachite and azurite) from the Sierra El Aramo (Asturias, northwestern Spain). The aim of this study was to supplement information in the existing reference database on the lead isotopic composition of Spanish ores. The Sierra El Aramo is particularly important because, while no data for the Asturian ores have been published so far, this northern province of Spain has played a significant role in terms of copper exploitation and metallurgy since the Copper Age.  相似文献   
32.
This paper presents a visualization system based on metric data to manage and disseminate archaeological information on the Internet. We describe the integration of two different types of sensors: laser scanning and close‐range photogrammetry. How we created an automatic and hierarchical approach based on processing and matching the images coming from a digital camera and a terrestrial laser scanner is also shown. This development has created a visualization system combining spherical photographs and georeferences for graphical and numerical data acquired by the sensors. The case study where we have applied this method is the Palaeolithic rock art of the Llonín Cave (Asturias, Spain), which has been declared a World Heritage Site by UNESCO and has restricted public access. Our results demonstrate that this tool integrates data, metadata, services and information, which simplifies the location, identification, selection and management of archaeological information.  相似文献   
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34.
Y. LIU  G. CHI  K. M. BETHUNE  B. DUBÉ 《Geofluids》2011,11(3):260-279
The Red Lake mine trend, a deformation zone in the Archean Red Lake greenstone belt that hosts the world‐class Campbell‐Red Lake gold deposit, is characterized by abundant foliation‐parallel iron‐carbonate ± quartz veins with banded colloform‐crustiform structures and cockade breccias overprinted by silicification and gold mineralization. There is an apparent incompatibility between the cavity‐fill structures of the veins and breccias (typically developed at shallow crustal depths) and the upper greenschist to lower amphibole facies metamorphic conditions recorded in the host rocks (indicating relatively deep environments). This, together with the development of veins along the foliation plane, represents an enigmatic problem that may be related to the interplay between fluid dynamics and stress field. We approach this problem through systematic study of fluid inclusion planes (FIPs) in the vein minerals, including the orientations of the FIPs and the pressure–temperature conditions inferred from fluid inclusion microthermometry. We find that fluid inclusions in the main stage vein minerals (pregold mineralization ankerite and quartz and syn‐ore quartz) are predominantly carbonic without a visible aqueous phase, whereas many inclusions in the postore stage contain an aqueous phase. Most FIPs are subvertical, and many are subparallel to the foliation. High fluid pressure coupled with the high wetting angles of the water‐poor, carbonic fluids may have been responsible for the abundance of brittle deformation features. The development of subvertical FIPs is interpreted to indicate episodic switching of the maximum principal compressive stress (σ1) from subhorizontal (perpendicular to the foliation) to subvertical (parallel to the foliation) orientation. The subvertical σ1 is favorable for the formation of foliation‐parallel veins, as fractures are preferentially opened along the foliation in such a stress regime, the origin of which may be linked to the fluid source.  相似文献   
35.
The present study shows how multivariate analysis and variable selection techniques can be used in archaeological provenances studies to improve classification performances. Neutron activation analysis (NAA), in combination with stepwise linear discrimination analysis (SLDA) (capable of simultaneously performing variable selection and classification), was applied to differentiate among limestone samples from different quarries across the north of France based on their compositional fingerprint. A hierarchical classification approach was followed, aimed at progressively assigning limestone samples to more specific sources of origin, from the broadest classification units (French regions) to the narrowest ones (individual quarries). The application of the stepwise variable selection procedure to extract the most discriminating compositional variables prior to each classification development allowed us to obtain a perfect separation between the limestone categories considered at every classification stage (all samples were correctly classified and predicted in all cases). The high‐quality results obtained were even more remarkable considering the relatively small number of significant variables selected in each case using the SLDA method. An illustrative example was provided in order to demonstrate that the classification strategy proposed can actually allocate an unknown sculpture to a particular quarry of origin.  相似文献   
36.
This paper presents a quantification method for archaeological molluscs using fragmentation categories. By employing the data from nine prehistoric sites (13 000 to 5000 bp ; 15 700 to 5700 cal bp ) in Cantabrian Spain (northern Spain), it has been shown that traditional methods, based on one or two anatomical elements, systematically produce a loss in the minimum number of individuals (MNI) that is sometimes significant. This paper also proposes using fragmentation categories in the calculation of the fragmentation index. In addition, based on these indices, a reflection is made on the difficulty involved in associating the amount of fragmentation of the shells with the taphonomic processes that have occurred at the archaeological sites, especially in discerning which agents have caused the fragmentation.  相似文献   
37.
In the 1950s and 1960s, the travellers, explorers, authors, and filmmakers Ji?í Hanzelka and Miroslav Zikmund became celebrities both in Czechoslovakia and abroad. The Communist cultural authorities actively supported the transformation of the two men into cultural icons, which could be exploited as a model for the suppression of ‘old’, ‘decadent’, and indeed ‘popular’ culture, and as a tool for recruiting members of the intellectual, cultural, and social elites into its service. Hanzelka and Zikmund’s multimedia travelogues, as well as their dashing public personae, blended in a unique way the ‘high’ and ‘low’, the accessible and unreachable, the familiar and the exotic, in the officially promoted culture of the time. But in the later 1960s, as Hanzelka and Zikmund’s political loyalties towards some form of reform socialism became more blatant, the two men fell into disfavour, and they found themselves banished from the public sphere following the events of 1968 until the regime fell in 1989. This article investigates how the curious ‘command celebrity’ of ‘H&Z’ straddled socialist ideology and capitalist consumerism, political affirmation and cultural critique.  相似文献   
38.
Journal of Archaeological Method and Theory - Fish taphonomy from archaeological sites provides considerable useful information about human behaviours and environmental contexts as potential food...  相似文献   
39.
Pre‐Romanesque murals at Kosto?any pod Tríbe?om, Slovakia, have been investigated by portable X‐ray fluorescence and by microanalytical methods to identify painting materials (pigments and binders), and to explain the degradation of colours. Today, missing green and blue shades have been reconstructed according to residual concentrations of Cu, which correspond to copper chlorides—products of salt corrosion of the copper carbonates azurite and/or malachite, accelerated by micro‐organisms. As confirmed by powder X‐ray microdiffraction, original minium (Pb3O4) has been transformed to brown–black plattnerite (PbO2). In increased humidity, even insoluble pigments are washing down from the walls and the intensity of colours further diminishes.  相似文献   
40.
We report a molecular methodology to obtain and analyse ancient bacterial DNA from archaeological dental calculus. Recent and archaeological DNA samples, as old as 4000 bp , were successfully extracted and amplified with species‐specific PCR primers. We propose this approach in order to: detect the presence of specific bacterial species infecting past human populations; compare the composition of ancient oral microbiomes among human populations; and analyse the genetic variability and covariation of bacteria and human host populations. Genomic analysis of bacteria from dental calculus is a promising source of evidence for palaeopathological and micro‐evolutionary studies, focused either on micro‐organisms or their human hosts.  相似文献   
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