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1.
Since 2005 we have been utilizing accelerator mass spectrometry (AMS) 14C dating in research on calcium oxalate crusts associated with open air rock art of the Iberian Peninsula. In this paper we present two dates linked with three eye-idol pictographs at Abrigo de los Oculados (Henarejos, Cuenca, Spain). Radiocarbon ages for these motifs agree with the expected iconography-based archaeological chronology. Such oxalate dates could provide an independent basis for evaluating chronological theories for post-Palaeolithic sites, designated in the UNESCO World Heritage List as Rock Art of the Mediterranean Basin on the Iberian Peninsula.  相似文献   

2.
This paper proposes a Bayesian model for the 14C chronology of Sicilian Early and Middle Bronze Age, with a specific focus on the northeastern sector of the island. Building on the available 14C determinations, the model allows addressing a number of chronological questions left open in literature, making a first step towards an independent absolute chronology. The analysis put the start of the earlier part of Early Bronze Age (Capo Graziano 1-Casa Lopez phase) between 2400 and 2175 cal BC, and the end at about 1960 cal BC. The advanced stage of the same period (Capo Graziano 1-Filo Braccio phase) is likely to have started and ended around 1960 and 1730 cal BC respectively. The model indicates that the time slot with the highest posterior probability for the start of the Middle Bronze Age–Milazzese (Portella phase) is between 1490 and 1460 cal BC. This turns up to be earlier than held to date. Notably, the model enables for the first time to bracket the development of the later stage of Early Bronze (Capo Graziano 2-M. di Capo Graziano phase) between 1730 (end of Filo Braccio phase) and 1490/60 cal BC (start of Middle Bronze Age–Portella phase). The latter date is earlier than usually held for the end of Capo Graziano 2. The existence of a narrow gap between the end of the latter and the start of Middle Bronze Age-Portella phase is tentatively proposed only on stratigraphic grounds. Further, the analysis enables for the first time to pinpoint and quantify the lag that is likely to have existed between the start of those Sicilian prehistoric phases and the appearance of Late Helladic imports. The comparison with the Aegean 14C Bayesian chronology indicates that a time lag (about 45 yr) is likely to have occurred between the start of Capo Graziano 2 and of the Late Helladic period. A time lag between 20 and 70 yr is likely to have existed between the start of the Sicilian Middle Bronze Age and of the Late Helladic III. Arguments tentatively supporting the narrower interval are also discussed.  相似文献   

3.
The 14C record for the Upper Paleolithic in Siberia has remained largely unevaluated and includes good, bad, and ugly dates. Too often researchers accept either all published dates or only those dates that tend to support proposed chronological hypotheses, regardless of sample quality and association. This article systematically evaluates all published 14C dates (including several newly obtained AMS dates) from middle and late Upper Paleolithic sites in the Enisei River valley of south-central Siberia to establish a reliable chronology for the region and address the tempo of modern human dispersals in Siberia during late Pleistocene times. The revised chronology indicates humans were present before and after the Last Glacial Maximum, but absent during this climatic event. Results also suggest that human population in the region may have increased during the Oldest Dryas.  相似文献   

4.
The organization of Classic Maya society emerged from diverse and overlapping social interactions which shaped a dynamic political landscape. Vying for power, elites legitimized their status by claiming ancestry from various supernaturals and engaged in conspicuous displays of competition, warfare, and ritual practice which were often recorded on stone monuments. By examining the inscribed relationships between Maya centers, we chart organizational changes in sociopolitical networks throughout the Classic period. Methods derived from social network analysis are used to examine temporal changes in the distribution and centralization of political power through different network interactions. We examine the intersection of antagonistic, diplomatic, subordinate, and kinship relationships and discuss how these overlapping networks contributed to dynamic changes in the Classic period. This case study demonstrates how current network analysis techniques can contribute to archaeological studies of the scalar dynamics and organizational changes of past social and political systems.  相似文献   

5.
It is now three decades since Waterbolk introduced evaluation criteria to 14C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of 14C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large 14C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of 14C dates.  相似文献   

6.
Abstract

Excavations near the ceremonial precinct of El Pilar, an important Maya center in Belize, exposed a Late Classic period concentration of almost 200 broken limestone spindle whorls. A program of experimentation demonstrated that the whorls were purposely destroyed, possibly as part of a ritual event or events. Such rituals may have been part of a strategy to enhance the status of spinners by honoring deities associated with spinning.  相似文献   

7.
前言 1949年,碳十四断代的创始人利比(W.F.Libby)公布了第一批碳十四年代数据,宣告碳十四测年方法取得成功,轰动了整个考古界和地质学界。碳十四  相似文献   

8.
This study presents the results of 44 new 14C analyses of Danish Early Iron Age textiles and skins. Of 52 Danish bog finds containing skin and textile items, 30 are associated with bog bodies. Until now, only 18 of these have been dated. In this paper we add dates to the remaining finds. The results demonstrate that the Danish custom of depositing clothed bodies in a bog is centred to the centuries immediately before and at the beginning of the Common Era. Most of these bodies are carefully placed in the bog – wrapped or dressed in various textile and/or skin garments. The care with which these people were placed in the bog indicates that they represent a hitherto unrecognised burial custom supplementing the more common burial pratice for this period.  相似文献   

9.
The Upper Palaeolithic site of the Abri Pataud (Dordogne, France) has been the subject of numerous14C age determinations which cover the period from 20,400±450 years (OXA-373) to 34,250±675 years (Grn-4507). The racemization ratios of aspartic acid have been determined in 26 fossil bones. The bones are present in two different sedimentary surroundings: levels (fine deposits with numerous artefacts and fossil bones) and “éboulis” (coarse deposits derived from the neighbouring limestone cliff). Racemization ratios for total aspartic acid have a poor correlation with14C ages (respectivelyr2=0·59 and 0·82 for the two environments) but apparent racemization rates are clearly dependent on the type of deposits (levels: K=4·4×10−6year−1; éboulis: K=9×10−6year−1).Racemization ratios of aspartic acid in a high molecular weight protein fraction (>10,000 Da) correlate much better with14C ages (r2=0·999) for the samples from the levels (k=2·1×10−5year−1). From this regression line we estimate ages for two Aurignacian levels: level 6≈29,560 years and level 9≈30,440 years .It is noteworthy that none of the regression lines intercepts the origin. Racemization of aspartic acid appears to occur only after a delay of many thousands of years. This phenomenon could be the result of a coupling between the degradation of proteins and the racemization of amino acids.  相似文献   

10.
The Siloam Tunnel (ST) is the best-identified biblical structure that can be entered today. We use geological, structural, and chemical features of ST and its internal deposits to show that it is an authentic engineering project, without any pre-existing natural conduit that could have guided its excavators. Radiometrically and historically dated to ∼700 BCE, ST pinpoints the technological advance in leveling techniques that was essential for the construction of such a long tunnel without intermediate shafts. A combination of geological and archaeological evidence demonstrates that the circuitous route of ST and the final meeting of the two excavating teams are associated with continuous modifications of the plan to allow acoustic communication between hewers and the surface teams. Hydraulic plaster was applied throughout the tunnel in order to seal voids of dissolution and tectonic origin. Organic material accidentally entrapped in the plaster was carbon 14 dated, and speleothems were dated by U–Th, both corroborating the historic and epigraphic evidence ascribing the engineering advance in tunneling techniques to the Judahite King Hezekiah.  相似文献   

11.
An ancient bronze statue of an athlete with a strigil (known as Apoxiomenos) – was raised from the north Adriatic Sea in 1999. In order to help to determine its place and date of manufacture various scientific techniques were used. 14C dating performed by the Accelerator Mass Spectrometry (AMS) on the organic material found inside the statue gave calibrated dates between 100 B.C. and 250 A.D. Non-destructive analysis performed by portable X-Ray Fluorescence (XRF) system and external beam Particle Induced X-Ray Emission (PIXE) spectroscopy could not provide representative results for metal alloy composition due to the electrochemical deterioration of the surface of bronze in seawater. This was observed by the analysis of alloy cross-sections performed by the proton microprobe. The analysis showed much higher lead concentrations on the surface of the bronze than inside, confirming that realistic alloy composition can be only performed on samples taken from at least 0.6 mm below the surface. Subsequent micro-PIXE analysis on metal cross-section showed inhomogeneous lead concentrations between 1 and 12%. Lead isotope analysis for provenance investigation has been done on 15 samples using Multi Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICP-MS). Analysis showed that lead isotope composition is consistent with some of the lead ores originating either from the Eastern Alps or from Sardinia. Altogether, the results lead to the conclusion that the statue is not of a Greek origin, but most probable it is a Roman copy of the Greek original.  相似文献   

12.
Two significant events in the late Holocene history of Madagascar were (a) the arrival of people, and (b) the loss of nearly two dozen species of land vertebrates in the socalled “subfossil extinctions”. The consensus is that the faunal losses occurred shortly subsequent to human arrival, but the timing of these events is poorly constrained. The minimum age for initial human presence on the island may now be set at approximately 2000 bp, on the basis of AMS 14C dates for human-modified femora of extinct dwarf hippos from SW Madagascar. Assuming that this date also marks the beginning of deleterious human interactions with the subfossil fauna, and assuming that this fauna became completely extinct by 900 bp, the width of the anthropogenic “extinction window” may have been as long as c. 1000 a. This estimate, nearly twice the length of previous ones, is close to the unadjusted minimum for the duration of the terminal Pleistocene extinction event in the Americas. Whether or not this length of time comports with theoretical expectations of a “blitzkrieg” pattern of losses is uncertain, but greater refinement in dating the end of the subfossil extinctions is unlikely to produce radically shorter estimates of duration.  相似文献   

13.
Anomalously 13C-depleted carbon stable isotope values from closed forest ecosystems have been termed the ‘canopy effect’. Originally this was ascribed to recycling of depleted carbon from forest floor decomposition of organic material, although others have suggested that it is equally likely to be due to variations in leaf-level processes in response to increased shade. This depletion in the heavier carbon isotope is passed on to woodland herbivores feeding within the forest environments. A similar isotopic depletion has also been reported in the archaeological literature from more open temperate woodland settings, but no measurements have been made on the plants at the base of the food chain in order to quantify the effect. In this study we attempt this by examining the carbon and nitrogen stable isotopic values of different species of grasses from a range of open to closed habitat settings within Wytham Wood, Oxfordshire, UK. We find a strong relationship between carbon isotopic depletion of plant tissue and lowered light intensity with an up to 5‰ shift between grass grown in open and closed locations. In order to follow this up the food chain, we also report data on wool from sheep grazing in open pastures near the Wood, and on fallow deer living within the woodland, but which turn out not to show a strong canopy effect, probably related to their feeding strategies. We conclude that there is indeed a strong ‘canopy effect’ in temperate woodland, probably related to differential light levels, but that not all apparently woodland-dwelling mammals show such an effect. We also show considerable isotopic variation at the base of the food chain, which should counsel caution when attempting to interpret dietary isotopes using mixing models.  相似文献   

14.
This paper presents the results of new stable isotopes (carbon and nitrogen) analysis of human, faunal and fish remains from thirteen cemeteries from the Middle and Lower Dnieper Basin, Ukraine. The results are integrated with earlier analyses, undertaken solely on human samples, in order to provide a comprehensive overview of subsistence across the Upper Palaeolithic through to Eneolithic periods in this region. This is the first time that a combined sample of human, faunal and fish remains has been studied in order to interpret subsistence strategies across these periods in Ukraine. The total dataset comprises 113 samples of human, faunal and fish remains, 59 of which include new analyses of faunal and fish remains that have not previously been made available for study (Table 1). The analysis of the faunal and fish remains allows for a consideration of trophic levels which indicates that the consumption of freshwater fish occurs from the Epipalaeolithic period onwards. Whilst the majority of the cemeteries and the individuals therein cluster in relatively tight groups, there is a significant offset between the human and faunal samples due to the consumption of freshwater resources. The fish samples analysed in the study appear to exhibit a relatively random distribution when compared to the other samples analysed. In general, freshwater resources remain significant through until the end of the Neolithic period and into the Eneolithic period at the sites investigated.  相似文献   

15.
Bone collagen extracted from 14 humans from the Mesolithic cemetery of Vasilyevka II was analysed for their δ13C and δ15N ratios. This cemetery is one of only two later Mesolithic cemeteries from the Dnieper Rapids region, being dated to 7300–6220 cal BC on the basis of three radiocarbon determinations. This analysis provides insights into the nature of the diet of the Dnieper populations at the very end of the Mesolithic period, prior to the adoption of pottery in the region, and the assumed shift towards the exploitation of domesticates in the economies of the populations of the Dnieper region, and considers these in relation to broader temporal indicators of diet in the region.  相似文献   

16.
The Middle to Upper Palaeolithic transition is the key period for our understanding of Neanderthal and modern human interactions in Europe. The site of Les Cottés in south-west France is one of the rare sites with a complete and well defined sequence covering this transition period. We undertook an extensive radiocarbon dating program on mammal bone which allows us to propose a chronological framework of five distinct phases dating from the Mousterian to the Early Aurignacian at this site. We found that the Mousterian and Châtelperronian industries are separated from the overlying Protoaurignacian by a gap of approximately 1000 calendar years. Based on a comparison with Upper Paleolithic sites in Europe we see an overlap in the ages of Châtelperronian industries and Aurignacian lithic assemblages, which are usually associated with Anatomical Modern Humans, which is consistent with an acculturation at distance model for these late Neanderthals. The Proto and Early Aurignacian appear contemporaneous indicating that this transition was rapid in this region. Anatomically Modern Humans are present at the site of Les Cottés at least at 39,500 cal BP roughly coincident with the onset of the cold phase Heinrich 4.  相似文献   

17.
In 1969, Ford offered a comprehensive model for the diffusion of ceramic production and Formative lifeways in the New World. Although criticized as simplistic, it was echoed by other unitary models, such as Lathrap's spread of Tropical Forest culture outward from a lowland South American hearth. Radiocarbon dates suggest that the earliest American pottery appears in the Amazon basin as early as 6000 B.C. However, there is little support for an ex Amazonas lux spread of pottery technology. Diffusionary models predict early complexes will resemble one another at first and then diverge over time, but comparative analysis reveals substantial variability even at the earliest time level. Heterogeneity among the earliest complexes indicates several likely hearths for the independent evolution of ceramic production, including (1) lowland Brazil, (2) northern Colombia, (3) coastal Ecuador, (4) coastal Peru, (5) central Panama, (6) southern Mesoamerica, (7) the southeastern United States, and (8) the central United States.  相似文献   

18.
Demineralization of bone for collagen extraction is most commonly performed using dilute hydrochloric acid (HCl) despite the fact that little data exists on the effects of differing acid concentration or treatment time on the quantity and quality of collagen extracts and that hydrochloric acid is extremely effective at hydrolyzing peptide bonds. Data on yield, elemental composition, and isotopic signature from bone collagen obtained from multiple extractions performed on two large ancient human bone samples from prehistoric Puerto Rico indicate that there is no meaningful difference between acid treatments ranging from 0.05 to 0.2 M concentration and 24–120 h of treatment. As such, a shorter course of demineralization using more concentrated acid would appear to produce quality results in a shorter time.  相似文献   

19.
Bulk δ13C values on charred cooking residues adhering to pottery sherd interior surfaces have been used as a source of information on the histories of maize in various locations in the western hemisphere. This approach is based on an assumption of a linear relationship between the percent maize in the resource mix cooked in a pot and δ13C. Previous experiments suggest that this relationship is non-linear, and maize may not be identified from bulk δ13C values even when it contributed substantially to the resource mix. A second round of experiments, presented here, indicates that the mobilization of carbon from maize and C3 resources over time is the critical variable in residue formation and the resulting bulk δ13C value. This is influenced by the form of maize being cooked.  相似文献   

20.
Despite uniform geochemistry 40Ar/39Ar ages of 0.6, 1.25, and 1.3 Ma on obsidians from a source flow (Worja) and from archeological artifacts at the sites of Kulkuletti (near Gademotta, Ethiopia) have been interpreted to suggest that they derive from different source flows of different ages. A further suggestion is that the magmatic source of the obsidian flows was chemically homogeneous between 1.3 Ma and 0.6 Ma. Chemical analysis of these obsidians indeed suggests that they derive from a single flow. Reexamination of the argon isotopic data reveals that argon isotopes may have been fractionated within the flow, so that the assumption of an atmospheric 40Ar/36Ar ratio of 295.5 is inappropriate to use for computing ages. Three groups of data are apparent, and internally all yield ages near 1.3 Ma if the intercept value for 40Ar/36Ar from an isotope correlation plot is used for computation instead of using the atmospheric ratio. The Soret thermal diffusion effect provides a possible mechanism of fractionation of argon within the obsidian flow that is of approximately the right magnitude to explain the observations by in-diffusion of already fractionated atmospheric argon.  相似文献   

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