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1.
Torres et al. (2010 ) published a series of radiocarbon, AAR, ESR and OSL dates from the site of El Sidrón, northern Spain, which is notable for the discovery of the partial remains of 12 Neanderthals. Whilst the non‐radiocarbon methods suggested an age beyond 32 600–46 300 years, direct radiocarbon dates on the human fossils were inconsistent, ranging between 10 000 and 50 000 bp . This study uses the ultrafiltration pre‐treatment protocol to obtain a date of 48 400 ± 3200 bp (OxA‐21 776) on a bone fragment and confirm the antiquity of the Neanderthal assemblage. Moreover, it demonstrates the comparability of the ultrafiltration and ninhydrin bone radiocarbon pre‐treatment protocols, and highlights the need for appropriate screening methods where valuable collections with poor biomolecular preservation are sampled for collagen extraction.  相似文献   

2.
The article is divided into four main sections in each of which a key aspect of radio-carbon dating is discussed with emphasis on the practical implications for users of dates. The four topics which the article attempts to deal with are, in turn, (i) the effect on the radiocarbon timescale of the variations in atmospheric 14C now known to have occurred in the past and the role of other absorlute dating methods in investigating these, (ii) laboratory measurement of 14C, (iii) selection of optimum samples for dating and (iv) some of the limitations of the final dates. The theme is essentially that the technical difficulties of radiocarbon measurement in the laboratory have been overcome to the extent that the physical measurements can now be made with high precision, that is to within ±1% or better, as a routine. Thus, it is more important than ever (a) that only reliable samples having very firm associations should be dated and (b) that pretreatment of such samples by the dating laboratory to remove any age contaminants should be completely effective. However, in addition to the recognized statistical limitations, the absolute accuracy of radio-carbon dating is limited by the past 14C variations. Coupled with the requirements of proper association and pretreatment of samples is the long-term need to establish an overall correlation between radiocarbon and calendar years. At present this is still a matter for final agreement by the laboratories concerned. Meanwhile, when all possible steps have been taken to ensure the reliability of the date messurements, these can strictly only be compared with one another in terms of radiocarbon years bp. In practice this is often too restrictive but any attempts at calibration must be regarded as approximations for the time being. In this article the lower and upper case notation advocated in Antiquity46, 265, for radiocarbon and calendar years respectively has been followed.  相似文献   

3.
In the early 1900s shells of a large freshwater mussel, Margaritifera auricularia (Spengler), were discovered in calcreted gravel dredged from the channel of the Thames at several sites between Mortlake and Battersea in west London. These specimens were said to have been associated with Neolithic polished stone axes, supposedly as food remains. M. auricularia is now extinct in Britain, but it has been reported living in several large rivers in southern Europe although apparently not in recent years. Three radiocarbon dates of 4140±50, 4340±45 and 4860±40 bp have been obtained from Thames specimens, supporting a Neolithic age for these shells. The theory that the shells represent debris from imported human food is discounted and it is considered more likely that M. auricularia was actually living in the Thames in Neolithic times. Its extinction in Britain should be seen as part of a general recession during the Post-glacial, as revealed by fossil occurrences to the north and east of its present-day range.  相似文献   

4.
Critical evaluation, tree-ring calibration, and statistical analysis of 95 radiocarbon dates from neolithic and predynastic sites in Upper Egypt and the Delta provide the following average age estimates in calendrical years BC. Early Fayum Neolithicca 5200 to 4500 BC Early Merimda Neolithicca 4800 BC Late Merimda Neolithic ?4400 BC Late Fayum Neolithicca 4000 BC Late Badarian? (Hemamieh)ca 4400/4000 BC Early Nagada (Nagada)ca 3750 BC Hierakonpolis (Locs 11 & 29)ca 3550 BC Late Nagada (South Town)ca 3450 BC Other sites or periods are not adequately dated. In addition, further dates are needed to bolster thistentative framework.  相似文献   

5.
Chronological evidence for the Iberomaurusian is currently very limited and there are problems with some of the published radiocarbon dates. In this paper we present new AMS dating results from well-stratified cave sequences at Ghar Cahal, Kehf el Hammar and Taforalt in northern and eastern Morocco. The longest of these sequences, from Taforalt, shows an intermittent occupation history spanning the period ca. 18,000–11,000 bp (radiocarbon determinations presented in this paper are expressed as ka bp or bp, whilst approximate calendar ages are expressed as Cal bp) with a marked intensification of cave use soon after ca. 13,000 bp. Using calibrated AMS ages in comparison to sea surface temperature evidence from the Alboran Sea core MD95-2043 and more generally to Greenland ice δ18O core records, we suggest that there may have been a relationship, albeit a complex one, between climatic events and cave activity on the part of Iberomaurusian populations.  相似文献   

6.
A new AMS radiocarbon date has been obtained from a Siberian human bone sample taken directly from a cranial fragment. The specimen comes from the north‐east Siberian site of Pokrovka 2 (55019′46.30″N, 92026′48.80″E). The remains consist of the anterior portion of the cranium or the superior part of the face; that is, the forehead and the roof of the eye sockets. Sadly, indifferent features of the frontal bone do not allow a confident diagnosis of the sex of the individual. The evidence suggests, however, that the remains are probably those of a young adult (teenager) and an anatomically modern human, rather than a Neanderthal. Radiocarbon dating was undertaken at the Oxford Radiocarbon Accelerator Unit (ORAU). The radiocarbon age determination of the bone fragment, 27 740 ± 150 bp (OxA‐19850), is one of the earliest direct dates for a modern human from Siberia. The Pokrovka cranial fragment dates to the middle Upper Palaeolithic of Eurasia and is broadly contemporary with the human remains from the famous eastern European site of Sunghir. When the radiocarbon age is compared with the Cariaco Basin 14C data set and the Greenland oxygen isotope record of NGRIP, it corresponds with Greenland Interstadial 5, a warmer phase of the Last Glacial period, although this is a preliminary conclusion, and is based on climate records that may or may not be wholly synchronous between the two locations.  相似文献   

7.
Some radiocarbon dates for ancient Egypt have been significantly offset from the established historical chronology (see Bonani et al., 2001). In this paper, short-lived plant species collected in Egypt between 1700 and 1900 AD were used to investigate the possibility that the radiocarbon record had been influenced by reservoir effects. AMS radiocarbon measurements were made on 66 known-age samples, resulting in an average offset from expected values of 19 years. The implications of this minor discrepancy on the likelihood of a reservoir process are discussed, and the agreement of the data with recent models of radiocarbon seasonality is also considered.  相似文献   

8.
Trou de Chaleux and Goyet are caves situated less than 30 km apart in Belgium that contain stratified Magdalenian artefacts and butchered faunal remains. Published radiocarbon dates suggest that both sites were contemporaneously occupied during to the Late-glacial interstadial. It has previously been suggested that the Trou de Chaleux Late-glacial faunal remains might be slightly older than those at Goyet Cave, and that Trou de Chaleux has two phases of occupation during the Late-glacial interstadial. However, the limited number of radiocarbon dates currently available makes it impossible to determine whether the sites are truly contemporaneous, and the assessment of their absolute chronologies is complicated by a plateau in the calibration curve. In this paper, bone collagen δ13C and δ15N signatures of horse bones from the two sites are used to reconstruct local palaeoenvironments. We hypothesise that if occupations at the two sites were contemporaneous, the horse collagen δ13C and δ15N isotope signatures from both sites will be similar, since comparable carbon and nitrogen isotopic values would reflect similar diets, ecologies and environments. To provide clear dating parameters, new AMS radiocarbon determinations are also presented. Results show that horse collagen δ13C and δ15N isotope signatures at the two sites are different, indicating that the populations were not subject to similar diets, ecologies and environments. The new radiocarbon dates confirm that the horse bones from Trou de Chaleux date to the Late-glacial interstadial, but they also show that in Goyet Cave Horizons 1 and 2, older horse remains dating to ca. 32?000–27?000 14C yr BP are mixed with Late-glacial horse remains. The δ15N values of the Goyet Cave horse bones radiocarbon dated to the Pleniglacial are substantially higher than those that have Late-glacial radiocarbon dates. Therefore, we now hypothesise that the majority of the horse bones isotopically analysed from Goyet Cave Horizon 1 are Pleniglacial in age. Statistical analysis of the radiocarbon dates indicates that the Late-glacial occupation at the two sites was contemporaneous, and that while there may appear to be two phases of occupation at Trou de Chaleux, this may be an artefact of the radiocarbon calibration curve.  相似文献   

9.
Pollen analyses and radiocarbon dates from the bottom sediments in the Kaali main crater suggested that the crater group is at least 4000?C5000 years old. Investigations of silicate impact micro-spherules in surrounding mires (Raukas et al. 1995) put the age about 7500?C7600 yr BP. Recently we found both silicate and iron microspherules from organic sediments below well-dated beach ridge in Reo site what supports the conclusions that the most realistic age of the Kaali craters is 7600±50 14C BP (8335?C8537 cal BP) and the meteorite fall was from SSE to NNW.  相似文献   

10.
Using a database of Australian archaeological radiocarbon dates (n = 2996), this paper explores three key methodological issues associated with the use of summed probability plots of radiocarbon data: 1) the minimum sample size needed for a statistically reliable plot; 2) the effect of radiocarbon calibration on the structure of these plots; and 3) the application of a taphonomic correction to such time-series data. The results identify several protocols, recommended as best-practice when using summed probability plots: 1) a minimum sample size of 500 radiocarbon dates should be used, and the sample size and the mean of the standard deviations of the radiocarbon dates (ΔT) in the sample should both be reported; 2) a moving average trendline of 500-800 years should be used to offset the effects of the calibration process; and 3) Surovell et al. “Correcting temporal frequency distributions for taphonomic bias” [Journal of Archaeological Science 36 (2009) 1715-1724] is explored, with modifications and temporal limits (<25,000 cal years BP) proposed. Correction of time-series data using theoretical taphonomic correction curves is useful as a heuristic tool but can obscure real trends if applied routinely. Comparison between summed probability plots and other occupation data is presented and shows good correlation. However it is recommended that plots are supplemented by other archaeological indices and the cross-comparison of such multiple proxies will strengthen identification of occupation trends.  相似文献   

11.
The chronology of prehistoric Sami settlement sites has previously been established by conventional radiocarbon dating of bulk charcoal samples associated with hearths from sunken hut floors (stállo-foundations). Here we present results of a comprehensive dating exercise of stállo-foundations in the alpine area of northern Scandinavia using Accelerator Mass Spectrometry (AMS) radiocarbon dating of charcoal. Over a 3 km2 study area, AMS calibrated ages of hearth charcoal from 22 stállo-foundations across 12 sites securely date these features to between cal. AD 640 and AD 1180. Only small variations in age were found between charcoal samples from different areas of a given hearth. Statistical analysis of all the charcoal AMS radiocarbon dates obtained reveals that 12 stállo-foundations across nine sites are contemporaneous and date to the Viking Period (AD 800–AD 1050). The tightly constrained AMS-based chronology of stállo-foundations contrasts with the existing chronology based on conventional radiocarbon analysis, which places these features within a significantly greater time-frame of between AD 600 and AD 1900, with most dates ranging between AD 800 and AD 1350.This discrepancy is likely to result from the necessity of collecting composite hearth charcoal particles, which may originate from different phases of occupation, in order to achieve the required final carbon content for conventional radiocarbon analysis. We argue that the new AMS-based radiocarbon chronology of stállo-foundations presented here supersedes the existing chronology based on conventional (Gas Proportional counting) radiocarbon analysis and we advocate the use of AMS radiocarbon dating in future hearth investigations.  相似文献   

12.
Excavations in 1970, 1996, and 1999 at Site QJ-280, Quebrada Jaguay, in southern Peru, yielded enough dateable terrestrial plant material to establish an extensive radiocarbon chronology for the site. QJ-280 is one of oldest well-dated fishing sites in the Americas: it was occupied from the terminal Pleistocene to the mid-Holocene (about 13,000–8,300 calibrated years BP) based on 42 terrestrial radiocarbon dates, encompassing the Jaguay and Machas Phases of the local archaeological sequence. In addition to the terrestrial dates, radiocarbon measurements on valves of two marine surf clam (Mesodesma donacium) individuals from a single, well-dated mid-Holocene Manos Phase archaeological context have provided insight into marine upwelling conditions during the occupation of Quebrada Jaguay. The marine reservoir age varied between 130 and 730 14C years during the brief lives of the two clams (up to 5 years each), and varied by up to 530 14C years within an individual valve, suggesting strong and variable deep marine upwelling; conditions broadly similar to those that exist in coastal Peru today. These rapid variations in marine radiocarbon age suggest that marine radiocarbon dates from environments with variable upwelling could be skewed by up to hundreds of years.  相似文献   

13.
Uncertainties regarding the magnitude of freshwater radiocarbon reservoir effects can introduce random errors into dates on archaeological freshwater carbonates. As a result, many archaeologists avoid dating freshwater shells unless no other datable materials are available. The chronology of prehistoric occupation of the former Naval Petroleum Reserve No. 1 (NPR-1) at Elk Hills, Kern County, has been established with 50 radiocarbon dates on freshwater mussels (Gonidea and Anodonta sp.). Characterization of any freshwater radiocarbon reservoir effect is crucial for the accurate interpretation of inferred settlement and subsistence changes on the Elk Hills. Paired charcoal and freshwater mussels sampled from closely associated contexts were dated to identify a freshwater reservoir effect. Paired Anodonta and Gonidea sp. shells were dated to investigate interspecific differences in fractionation. Results indicate that a 340 ± 20 14C yr correction should be applied to conventional 14C dates on freshwater carbonates in the Buena Vista Basin before calendar calibration. Evidence of interspecific differences is inconclusive. Dates recalibrated with the reservoir correction indicate that widespread occupation of the Elk Hills is correlated with increasing precipitation towards the end of the Medieval Climatic Anomaly and during the Little Ice Age, suggesting that slough resource exploitation may have been driven by regional population pressure rather than drought-related declines in aquatic productivity.  相似文献   

14.
The excavation of tomb IGN 117 in Madâ’in Sâlih, ancient Hegra, in Saudi Arabia, produced a large amount of bones, objects and materials (leather, fabric, fruit, wood, amorphous organic substances) of the Nabataean‐Roman period (first to early fourth century AD). Two pieces of fabric and leather are of particular interest because they contained pierced dates (Phoenix dactylifera) strung together using date‐palm leaflets. These exceptional discoveries are poorly attested in Near Eastern funerary contexts. Together with other data from Madâ’in Sâlih, the southern Near East and Egypt, this interdisciplinary analysis leads to the reconstruction of part of the funerary practices related to the preservation and preparation of the body that occurred in tomb IGN 117. Finally, the analysis allows the questioning of the symbolic role of plant jewellery and the date palm in a funerary context.  相似文献   

15.
Genetic data from archaeological specimens provides a potent new approach for addressing questions in prehistory. Hair from archaeological sites is an important but overlooked data source amenable to molecular analysis. To date DNA identification from hair is limited to modern samples. Our study is the first to report DNA recovery from a 9800-year-old specimen. We report methods used to extract mitochondrial DNA and obtain accelerator mass spectrometry radiocarbon dates (AMS-14C) from hairs plucked from a piece of ancient bighorn sheep (Ovis canadensis nelsoni) skin found at Smith Creek Cave, Nevada. The ability to obtain reliable radiocarbon dates and DNA sequences from single ancient hairs opens new possibilities for addressing biological questions in prehistory.  相似文献   

16.
Abstract

This research radiocarbon dates human teeth and bones sampled from seven tombs from the archaeological site of Natfieh, Northern Jordan. The small number of artifact fragments uncovered, looting and disruption of the tombs in antiquity and/or recent times, and the continuity between the Greek and Roman burial traditions and similarity in tomb architecture impede determining accurate dates and chronology of the tombs. This research aims to ascertain the archaeological dates and the chronological sequence of the tombs and the artifacts uncovered. Results show that the probable earliest use of these tombs was between 90 BC and AD 20, and their probable latest use was from AD 126–236. Most probably, at Natfieh new tombs spread northward and carving the tombs started in the lower rock layers and later in the upper layers.  相似文献   

17.
The beginning of the Late Bronze Age in the Aegean has usually been thought to coincide with the start of the Eighteenth Dynasty in Egypt, and radiocarbon dates (which consistently suggest an earlier chronology) have been rejected by Aegean specialists because they do not agree with this view. Evidence from pottery is used to re-examine the links between the Aegean and Egypt, with the conclusion that the Aegean Late Bronze Age began during the Hyksos period.  相似文献   

18.
A pre‐industrial iron‐smelting site in Korea, whose period of active use is placed on typological grounds between the eighth and 18th centuries ad , has been dated using accelerator mass spectrometry and thermoluminescence. The ages of two charcoal samples were 77 ± 25 and 81 ± 25 years bp , with the calibrated date for both ranging from ad 1700 to ad 1955, while a clay fragment dated to ad 1650 ± 50. The results from typology and radiocarbon seem insignificant due to the considerable uncertainties involved, but in combination with the thermoluminescence result they place the most probable date of the site at around ad 1700.  相似文献   

19.
Thermoluminescence dates obtained from burnt flints and quartz recovered from the same sites are compared. For the Upper Perigordian level at la Vigne Brun (Loire, France), four quartz specimens and three flints yielded average ages of 27 400 ± 2300 and 26 900 ± 2200 years respectively, which are 15% greater than the radiocarbon age obtained for the same site (Evin 1982). For the neolithic site of la Vallée aux Fleurs (Loir et Cher, France), the respective averages of three flints and three ceramic sherds were 6830 ± 560 and 6570 ± 520 years.  相似文献   

20.
We conducted an identification of a substance isolated from a T‐shaped ornamental element excavated from a Globular Amphora Culture tomb at the Kowal 14 archaeological site in Poland. 14C dating indicated 4105 ± 35 bp (POZ‐21912) and 3990 ± 50 bp (POZ‐21910). Analytical methods such as SEM–EDS, XRD and FT–IR were applied to study the origin of its structure. The results of instrumental analysis and the archaeological context indicate that the adhesive substance investigated consists mainly of calcium carbonate (calcite, 78–88%), silica dioxide (quartz), sodium aluminium silicate (albite) and potassium aluminium silicate (microcline). The material might be a man‐made, mineral adhesive, a kind of lime mortar. The object is considered as the oldest European finding of this type outside the Mediterranean Basin. It provides evidence for the use of the lime calcination process in Central Europe as early as in the Late Neolithic, for which there were—up to now—no convincing premises.  相似文献   

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