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941.
942.
943.
T. De TORRES J. E. ORTIZ R. GRÜN S. EGGINS H. VALLADAS N. MERCIER N. TISNÉRAT‐LABORDE R. JULIÁ V. SOLER E. MARTÍNEZ S. SÁNCHEZ‐MORAL J. C. CAÑAVERAS J. LARIO E. BADAL C. LALUEZA‐FOX A. ROSAS D. SANTAMARÍA M. De La RASILLA J. FORTEA 《Archaeometry》2010,52(4):680-705
The age of Neanderthal remains and associated sediments from El Sidrón cave has been obtained through different dating methods (14CAMS, U/TH, OSL, ESR and AAR) and samples (charcoal debris, bone, tooth dentine, stalagmitic flowstone, carbonate‐rich sediments, sedimentary quartz grains, tooth enamel and land snail shells). Detrital Th contamination rendered Th/U dating analyses of flowstone unreliable. Recent 14C contamination produced spurious age‐values from charcoal samples as well as from inadequately pretreated tooth samples. Most consistent 14C dates are grouped into two series: one between 35 and 40 ka and the other between 48 and 49 ka. Most ESR and AAR samples yielded concordant ages, ranging between 39 and 45 ka; OSL dating results permitted adequate bracketing of the sedimentary layer that contained the human remains. Our results emphasize the value of multi‐dating approaches for the establishment of reliable chronologies of human remains. 相似文献
944.
Amongst a large number of ancient quarries scattered along the North African coast, those at Sidi Ghedamsy (Monastir, Tunisia) have supplied building stones of Pliocene age. Two lithofacies have been distinguished in the quarry faces: (i) fine sandy limestone, which has been used in the construction of Roman and Arabic monuments; and (ii) porous and coarse limy sandstone, which is of bad quality for construction. Laboratory analysis results confirm that the exploitation of stone in antiquity was well focused on the levels containing the first type. This is confirmed by geotechnical tests, which show that the fine sandy limestone is harder and less porous than the coarse limy sandstone. Extraction of these stones began in the Roman period. The Romans exploited the quarries using steel tools that permitted the extraction of blocks from several levels. In the eighth century, Arabic quarry workers continued the stone extraction using the same technique, but they produced blocks of small and medium size. Statistical measurements have been done on the quarry faces and on the walls of the Ribat in order to understand the degree of conformity between the dimensions of the extracted blocks and those used for building, and ultimately to attempt to date the quarries and the construction of the Ribat. 相似文献
945.
In this work 51 glass mosaic tesserae from decorations of the two Greek monasteries of Daphni and Hosios Loukas were analysed by inductively coupled plasma optical emission spectroscopy, electron microprobe analysis and X‐ray powder diffraction. On the basis of the chemical analyses, after discrimination between the tesserae of the original decorations and those from other periods, it was possible to outline the distinctive traits of Byzantine mosaic tesserae. In both the monasteries, the original mosaics were decorated with tesserae produced with plant ash based glass, either of the typical composition or a mixture with natron type glass. The samples from the Hosios Loukas decorations show a more homogeneous composition compared with those from Daphni. The major differences among the original samples are due to the presence of opacifiers and colourants. 相似文献
946.
A total of 52 South Italian red‐figure vases were subjected to neutron activation analysis. The primary aim of the study was to determine whether all Apulian red‐figure pottery datable to the period c. 430–340 bc was produced at the Greek colony of Taras, as has been widely assumed. Three chemically distinct compositional groups were isolated and compared to archaeological reference material from Taranto. The results of this comparison suggest that some Early Apulian red‐figure pottery may have been produced outside of Taras from the fifth century bc onwards. 相似文献
947.
A. DURAN M. C. JIMENEZ DE HARO J. L. PEREZ‐RODRIGUEZ M. L. FRANQUELO L. K. HERRERA A. JUSTO 《Archaeometry》2010,52(2):286-307
The employment of synchrotron techniques complemented by conventional laboratory systems has allowed us to deepen and improve our knowledge of Roman wall painting procedures. The palette identified in wall paintings from Pompeii and Herculaneum from the second century bc includes goethite, hematite, cinnabar, glauconite, Egyptian blue, and other components such as calcite and aragonite. Proof of the use of organic binders is provided by FTIR and PY–GC/MS. Therefore, the possibility of the use of ‘a secco’ techniques cannot be ruled out. Pigments in wall paintings are usually found in small percentages and conventional X‐ray diffractometers do not detect them. Synchrotron radiation – high‐resolution X‐ray powder diffraction has allowed identification with only a few micrograms of sample. 相似文献
948.
In 2005–2006 we initiated a major archaeological survey and chemical characterization study to investigate the long-term use of obsidian along the eastern shores of Lake Urmia, northwestern Iran. Previous research in the area suggested that almost all archaeological obsidian found in this area originated from the Nemrut Daĝ source located in the Lake Van region of Anatolia (Turkey). More recent research on obsidian artefacts from the Lake Urmia region has identified a significant number of obsidian artefacts with compositions different from the sources near Lake Van. This suggests that the obsidian artefacts are from a yet to be identified geological source, but possibly one that was not too distant. In order to advance our knowledge of Iranian obsidians and eventually refine provenance criteria we analysed obsidian from 22 Chalcolithic sites and some source areas. The compositions of both obsidian source samples and artefacts were determined using wave length dispersive X-ray fluorescence spectrometry (WDXRF). This paper presents results from the trace elemental analysis of both geological and archaeological obsidians, providing important new data concerning the diachronic relationship between lithic technology and raw material in the north-west of Iran. 相似文献
949.
This paper presents material characteristics and raw material provenance of the stone moulds for bronze slender daggers from Galdong. This type of bronze dagger is uniquely distributed in the Korean Peninsula and these stone moulds were the first to be found by excavation. The stone moulds were made of igneous hornblendite with course-grained holocrystalline textures. Based on petrological, mineralogical and geochemical characteristics, the original rock materials of the moulds were inferred to be derived from the Jangsu or Namwon areas which are about 50 km away from the excavation site. It is a notable achievement that this provenance study confirmed the domestic production of Korean-styled daggers. 相似文献
950.
V. PITTHARD S. WEI S. MIKLIN‐KNIEFACZ S. STANEK M. GRIESSER M. SCHREINER 《Archaeometry》2010,52(6):1044-1056
A recent restoration of a 17th‐century Japanese lacquer cabinet revealed various later treatments over the original black coating to maintain and preserve the high gloss of the oriental cabinet over the course of time and to meet changing tastes. The comprehensive investigation on a series of coating samples was executed by means of two hyphenated techniques: gas chromatography – mass spectrometry (GC–MS) and pyrolysis combined with GC–MS (Py‐GC–MS). The results showed that the original lacquer is based on urushi and linseed oil, while the past interventions are composed of sandarac, shellac and dammar. Additional microscopic studies proved the multi‐layer structure of the lacquer and the use of different pigments. 相似文献