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31.
This is the thirty‐fourth list of AMS radiocarbon determinations measured at the Oxford Radiocarbon Accelerator Unit (ORAU). Amongst the dates obtained for archaeological sites included here are the latest series of determinations from the key sites of Proskynas (Greece), Kova?evo (Bulgaria) and Khirbet Qeiyafa (Israel), as well as others dating to the Palaeolithic, Mesolithic and later periods. Submitters of the material provide comments on the significance of the results. 相似文献
32.
C. TRIBOLO N. MERCIER M. SELO H. VALLADAS J.‐L. JORON J.‐L. REYSS C. HENSHILWOOD J. SEALY R. YATES 《Archaeometry》2006,48(2):341-357
This paper presents the first TL dates for burnt quartzites and silcretes from the Still Bay layers of Blombos Cave (South Africa). These layers contained engraved ochres and marine shell beads that could be an early manifestation of symbolic and thus ‘modern’ behaviour by the Middle Stone Age humans. The procedure devised to calculate the ages is presented in detail, particularly with regard to internal microdosimetry, because the problems faced in estimating the dose rates require an approach different from the one usually used on flints and sediments. A mean age of 74 ± 5 ka was obtained for five burnt lithics unearthed in the BBC M1 member of the Still Bay layers. This result is in good agreement with both ESR dates on teeth and OSL dates on sediment, and demonstrates the great antiquity of the archaeological remains discovered at Blombos Cave. 相似文献
33.
J. E. ORTIZ T. TORRES M. R. GONZÁLEZ‐MORALES J. ABAD I. ARRIBAS F. J. FORTEA F. GARCÍA‐BELENGUER I. GUTIÉRREZ‐ZUGASTI 《Archaeometry》2009,51(1):123-139
Here, we provide the first report on the ages of 54 archaeological levels in 38 caves in northern Spain by means of the aspartic acid d /l ratio measurements in Patella shells, with good results. For this purpose, we developed an age calculation algorithm that allows the numerical dating of deposits from other archaeological localities in the area and nearby regions. We conclude that the sample size—that is, the number of shells analysed within a single level—reinforces the importance of analysing numerous specimens per horizon and the understanding of the time‐averaging concept. The ultrastructure of different species of Patella shells was also studied, showing calcite in their apexes and aragonite at their margins. 相似文献
34.
Sclerochronology and dendrochronology are based on series of incremental skeletal and cambial growths that have been correctly aligned in time via cross‐dating (i.e., incremental dating through synchronization of the growth variability on a visual and statistical basis). Here we report a study of the shell increments of two anthropogenic death assemblages of freshwater pearl mussel (Margaritifera margaritifera) originating from Finnish Lapland. First, we cross‐dated a new sclerochronology from an assemblage of river pearl mussel shells with unknown post‐mortem age. Second, this chronology was cross‐dated with the previously published sclerochronology of the same species and geographical source. Third, the composite of the two sclerochronologies was compared to dendrochronologies from Lapland. Temporal association of the two types of chronologies was markedly high, as confirmed by t‐values of 7.1 and 8.9, which are well above the acceptable limit of 3.5. Our study demonstrates the potential of sclerochronological and dendrochronological materials and techniques in assessing the contemporaneity (i.e., temporal overlap) and post‐mortem age of archaeomalacological deposits. In the palaeontological context, these results also show the wider possibility of dating shells with a large number of annual increments from natural deposits. 相似文献
35.
W.J. Rink H.P. Schwarcz H.K. Lee V. Cabrera Valdés F. Bernaldo de Quirós M. Hoyos 《Journal of archaeological science》1996,23(6):945-951
At El Castillo, in Cantabrian Spain, uncalibrated AMS14C dating has shown the transition from Mousterian to Aurignacian to occur at 39·3±1·6 kaBP. We found ESR tooth enamel ages from the basal Aurignacian level at El Castillo to be 36·2±4·1 ka (early and linear uptake). The enamel and dentine had very low U contents, but ESR ages are strongly dependent upon knowledge of the moisture content history of the sediments. Although the Aurignacian ESR age is 8% younger than the weighted average uncalibrated AMS14C age of 39·6±1·3 ka obtained from charcoal samples, we have shown that the methods agree within experimental uncertainty. However, since no precise14C calibration yet exists for this period of time, we are unable to specify which of the ages is more accurate, nor are we able ascribe the apparent age discrepancy to a particular deficiency in the ESR method. 相似文献
36.
R. G. BEDNARIK 《Archaeometry》1996,38(1):1-13
Epistemology has not kept pace with the progress experienced in the direct dating of rock art. This paper reviews the experimental methods that have been developed in recent years. While many do provide important information about the possible age of rock art, it is of concern that the precipitate archaeological interpretations these data are used for are often not warranted. Some are attributable to not understanding the severe qualifications that apply to most dating results, others perhaps to over-enthusiasm on the part of some researchers. The introduction of archaeological dynamics into direct dating of rock art threatens the reliability of this young methodology. Some of the pitfalls are considered in this paper, and a general rationale for the direct dating of rock art is developed. 相似文献
37.
Among the Nigerian cast copper‐alloy artefacts, the chronology of the Benin memorial heads has been the most fully worked out. Therefore, a study focused upon their elemental compositions is particularly likely to be interpretable in terms of development of the alloys used in their making. The elemental analyses, both published and unpublished, of 66 Benin heads, supplemented with seven analyses of some artefacts excavated from a well‐dated, very early Benin site, have been collected, analysed statistically and computed to the elemental analyses of 11 heads and figures from Udo. All but a very few of the Benin heads and artefacts separate into five compositional groups, indicating a chronological sequence of different alloying traditions. All but one of the Udo objects fall into a distinctly separate compositional group, together with two Medicine heads. The compositional groups correlate remarkably well with the stylistic types proposed by Dark. 相似文献
38.
The magnetic response derived from an iron‐smelting site was investigated by comparing magnetometry and magnetic susceptibility geophysical survey data and laboratory analyses of the magnetic characteristics of the furnace and slags. Magnetic analysis and microscopy (optical and SEM) of samples from the furnace lining and the slag deposits demonstrated the heterogeneity in the magnetic, morphological and mineral compositions of both materials. The comparison of the magnetic characteristics of the material with the geophysical survey data illustrated the importance of using both magnetometry and magnetic susceptibility survey techniques to maximize the information from an iron‐smelting site. The furnace was dated archaeomagnetically to the 14th century ad . The results demonstrate that the magnetic analysis of iron‐smelting sites is highly valuable, both to characterize sites and to improve the understanding of early iron‐working technology. 相似文献
39.
C. Roque P. Guibert E. Vartanian F. Bechtel R. Treuil P. Darcque H. Koukouli‐Chryssanthaki D. Malamidou 《Archaeometry》2002,44(4):613-633
The chronological sequence of a major reference site for Neolithic periods in southeastern Europe and the Aegean, Dikili Tash (Macedonia, Greece), has been reassessed by TL. Baked adobe material samples extracted from domestic ovens, directly associated with specific occupational levels, have been studied. The fine‐grain technique has been used for equivalent dose determination. K, U and Th contents and the equilibrium state of U‐series have been measured by low‐background gamma spectroscopy. Since the archaeological levels were already partly excavated, the environmental dose‐rate was evaluated by a reconstruction technique combining laboratory analysis and on‐site measurements. The TL results (weighted average of multiple age determination, oven 400, middle of the Dikili Tash I (DT‐I) phase, 5500 ± 320 bc ; oven 600, end of DT‐I, 4920 ± 310 bc ; house 3, DT‐II, 4260 ± 280 bc ; house 4, DT‐II, 4510 ± 410 bc ) are in general agreement with the timeframe deduced from previous radiocarbon dates. This convergence strengthens the settlement's chronology, established now by independent dating methods. 相似文献
40.
Three Natufian base camps in Israel—el-Wad, Hayonim and Eynan—have nearby basalt sources, but K/Ar ages indicate that their inhabitants obtained implements, made of Miocene-Pliocene and Quaternary basalts, further afield. The nearest locations, in which raw material sources representing the whole range of dated basalts occur within a relatively restricted area, are to be found east of the Jordan Valley, suggesting movement of the material some 100 km to el-Wad, 60 km to Hayonim and 20 km to Eynan. The exact nature of these longdistance contacts and the underlying social and economic systems and mechanisms are yet to be determined. 相似文献