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1.
I. K. BAILIFF 《Archaeometry》2007,49(4):827-851
Fired clay brick samples, obtained from a group of seven high‐status late‐medieval and post‐medieval buildings in England ranging in age from c. ad 1390 to 1740, were dated by the luminescence method using an optically stimulated luminescence (OSL) technique. The results obtained indicate that, when applied to quartz extracted from brick, the technique is capable of producing dates that are in consistently good agreement with independent dating evidence for the buildings. For six samples taken from a group of four dating ‘control’ buildings the mean difference between the central values of luminescence and assigned ages was 5 ± 10 years (SD, n = 6). The methodology used is appropriate for application to other standing buildings in other temporal and geographic regions, and may be used with confidence where conventional dating methods are less certain. The study also examines the luminescence characteristics of quartz and the characteristics of the lithogenic radionuclides in brick samples and identifies various aspects related to the assessment of experimental uncertainty in testing the reliability of the method.  相似文献   

2.
An unusual coarse, shelly sedimentary unit is found elevated above present mean sea level in a sheltered pocket embayment at Old Punt Bay in south‐eastern Australia. The coarse sediments, diverse microfauna, and large shelly macrofauna of mixed affinity suggest that the deposit is the result of high‐energy deposition. The deposit was previously thought to have been deposited 1000–1300 cal bp based on one shell dated using 14C and amino acid racemisation. However, additional 14C dating indicates a likely age of ~2500 cal bp . Regardless of age constraints, the presence of rock‐encrusting oyster shells and large articulated bivalves, suggests that the depositional event must have been capable of removing and transporting coarse sediments (rock clasts), bivalves, and oysters shells from a variety of seaward environments and depositing them with little abrasion, something storm waves are unlikely to do. The deposit may be tsunamigenic. If a tsunami origin is accepted, the new dating results indicate that it is possibly coeval with a tsunami event previously reported to have affected several other sites along the coast of New South Wales at c. 2900 cal bp . Consequently, this deposit provides evidence for the event at a new site and importantly, a tighter constraint on the likely date of the events occurrence. It further adds weight to the developing catalogue of palaeotsunamis that may have affected the south‐eastern coast of Australia. Regardless of the deposit's origins, if viewed from a coastal planning perspective, this deposit indicates that this part of the coast has experienced large‐scale overwash events in the past that if repeated, would be catastrophic. There are serious implications for risk management.  相似文献   

3.
A novel luminescence methodology for dating surfaces of granitoid rocks is presented, with encouraging results for archaeological stone structures. It is based on the zeroing of the latent signal of optically stimulated luminescence (OSL) in feldspar and quartz grains of the stone surface during exposure to daylight. When after bleaching the surface is shielded from light, the OSL signal builds up again, such that its intensity provides an age for the event of the last exposure to light. This event could be the construction or the destruction of stone structures or, for example, sedimentary deposition of granitic boulders, such as in fan deposits. The experimental approach utilizes a high spatial resolution detection technique (HR‐OSL) for OSL of minerals that are left in their original petrological context; that is, without any mineral separation. With this approach, steep gradients in microdosimetry at the surface and at grain boundaries become important and are discussed in detail. The new dating technique is successfully applied to a stone wall of the medieval castle of Lindenfels in southwestern Germany and the pre‐Columbian Nasca lines (geoglyphs) around Palpa in southern Peru.  相似文献   

4.
I. LIRITZIS 《Archaeometry》2006,48(3):533-547
The water diffusion mechanism in obsidian has been revisited with the advent of a new dating approach employing secondary ion mass spectrometry (SIMS). The water diffusion SIMS(+) profile and the concept of a surface saturation (SS) layer in obsidians both provide a sound basis for the new diffusion age equation (SIMS‐SS) and are supported by dated world examples ( Liritzis et al. 2004 ). Here, we present the basic physical–chemical analysis of the mass transport phenomenon on which the new dating method is based. The crucial age parameter of the SIMS‐SS dating approach for archaeological obsidians—that is, the surface saturation (SS) layer—is supported by both theoretical and experimental data.  相似文献   

5.
A. R. MILLARD 《Archaeometry》2006,48(2):359-375
Bayesian analysis of radiocarbon dates on Holocene archaeological sites has become well established. Application to Pleistocene sites dated by multiple techniques would be advantageous. This paper develops the necessary mathematical apparatus in the form of likelihoods for luminescence dating, and uranium‐series dating, and considers the possibility for amino‐acid racemization dating. Application of the new methods is illustrated using the stratigraphic sequences of dates from the sites of Saint‐Césaire and La Chaise‐de‐Vouthon. For application to amino‐acid racemization dating, fuller publication of data is found to be required.  相似文献   

6.
A parsimony analysis of the Narmada cranium from central India and a number of other demes and species of Homo concludes that the Narmada hominin shares a closer relationship with the European Steinheim specimen, than with Asian H. erectus or H. pekinensis. This suggests that the population represented by the Narmada cranium is likely to have had its origins in Europe rather than in Asia. Overall the available evidence supports an ‘Out of Africa’ scenario, as the early Asian hominins belong to a distinct clade which has no extant descendants and thus appear to represent an evolutionary ‘dead end’. The later African and European hominins are defined by a clade including early H. sapiens from Africa. The main difference between these two distinct clades is that the H. erectus lineage is defined by increasing degrees of neuro‐orbital disjunction associated with increased anterior cranial base extension, while the lineage leading to early H. sapiens is characterized by the opposite condition of reduced neuro‐orbital disjunction associated with increased anterior cranial base flexion. While there is also evidence of differential patterns of head and neck musculature between these two clades, they are of secondary importance. Preliminary dating of bovid remains found in association with the hominin cranium by the gamma spectrometric U‐series dating technique suggests a tentative minimum age of not less than 236,000 years. This is in agreement with evidence from biostratigraphical studies of the Boulder Conglomerate, which place these deposits in the Middle Pleistocene. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

7.
8.
Archaeomagnetic dating in the American south-west is progressing rapidly in terms of both method and application. Of particular importance has been the creation of a master curve of geomagnetic direction change for the region. However, confirmation, extension and refinement of this curve are always welcome contributions to the technique. So, efforts are under way to accumulate a large body of well-dated virtual geomagnetic pole positions and document these through publication so that the basis for dating samples of unknown age can be evaluated. This article adds 23 new dated pole positions to the list discussed in Eighmy (1991) and reports the results of our experiments with refining the south-west USA master curve, especially the creation of a new south-west master curve, SWCV595.  相似文献   

9.

Generally, two main opinions have been maintained concerning the age of the markets in northern Fenno‐Scandinavia: One asserting that the markets have their origins well before A.D. 1600, and possibly are dating from the Middle Ages; and the other suggesting that the markets may be constructions of the 18th century. The majority of studies relevant to the question of the markets have, however, been confined within strict geographical limits. Few efforts have been made to view the markets in a broader context, comprising the totality of the trade relations of northern Fenno‐Scandinavia. While giving the written evidence a critical and chronological sifting, the author of this paper stresses this perspective on the markets, as instruments of mediation between what is conceived as the three great trade systems embracing the northern part of Fenno‐Scandinavia.  相似文献   

10.
The study of tree rings has been used for over 100 years to inform climatic and geomorphological reconstructions. In mainland Australia, no tree species are currently recognised as providing reliable sources for such studies over extensive areas. Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods. The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies. This study initially examines the microstructure of samples of E. camaldulensis taken from the Barmah Forest to assess the applicability of the species to dendroecological investigation. It is found that samples of the species exhibit ring‐like structures, although there are areas of the samples that contain zones of growth without clear ring boundaries. The patterns of growth rings and zones are found to be common to many trees at a site, although the level of variability of pattern from tree to tree is high. Options for future development of the approach described here are to combine ring studies with isotopic‐based analysis to provide a combination of tree age and climatic history.  相似文献   

11.
A new thermoluminescence (TL) technique for determining the age of heated flint artefacts from archaeological sites is presented. It is a variant of the SAR protocol, which is usually used for OSL dating of sediment, but it is not based on a presumed model for fitting the dose–response curve. Dose recovery tests as well as comparisons with standard protocols show the accuracy of the new technique. It is found that the sensitivity of the thermoluminescence (TL) signal of flint in the orange–red waveband does not show severe changes due to the heating process while measuring the TL. This allows the application of a short SAR procedure, which requires only two dose points. The technique does not require as much instrument time as other SAR techniques, and thus is advantageous for dating very old samples. The major advantage of this new technique is the small amount of sample material required, which allows the dating of samples that are too small for standard TL dating techniques.  相似文献   

12.
S. M. BARNETT 《Archaeometry》2000,42(2):431-457
Dating of later prehistoric settlements relies heavily on potter; typologies in England and yet there has been little scientific dating in order to verify these typologies. In this work, luminescence dating techniques were applied directly to the pottery which forms the typological framework. Excellent agreement was obtained between the luminescence ages, and archaeological age ranges for known‐age pottery sherds with diagnostic form and surface decoration. A lower correlation, however, was found in several regions between the luminescence ages for undecorated body sherds and the archaeological assessment which was necessarily based solely on fabric, suggesting the need for reassessment of these fabric chronologies.  相似文献   

13.
The journal Archaeometry and its first co‐editor Martin Aitken played key roles in the development of archaeomagnetism. This paper briefly reviews all papers published in Archaeometry, and a few others, dealing with archaeomagnetic secular variation, archaeomagnetic dating, archaeointensity studies and related applications of magnetic studies to archaeology, to indicate some of the major developments over the past 50 years.  相似文献   

14.
U‐series dating was used to determine the growth rate of a feldspar‐to‐clay weathering rind in a mid‐Holocene Cascade–Olcott tradition andesite core, and luminescence dating (last exposure to sunlight) was used to date fine‐grained feldspars scraped from the surfaces of similar buried artefacts from a 14C‐sediment‐dated archaeological site (45KI464) on the wet western slope of the Cascade Mountains of Washington. For U‐series dating, we measured 226Ra excess (226Ra excess =226Ra –230Th) in five stratigraphic depth controlled rind scrapings. 238U, 232Th and 230Th were counted by alpha spectrometry, and 226Ra and 210Pb were counted by gamma spectrometry on each sub‐sample.  相似文献   

15.
In this study, solid‐state 13C magnetic resonance spectroscopy using cross‐polarization combined with high‐powered proton decoupling and magic‐angle sample spinning and Fourier transform infrared spectroscopy using a diamond anvil cell, are employed to give information about the organic functional groups present in charred and non‐charred solid organic residues and to give an insight into the degree of condensation of the chars. Residues were preserved in ceramic vessels recovered from the indigenous settlement of Uitgeest–Groot Dorregeest, dating back to the Roman period. In addition, the application of these solid‐state techniques is used for verification of earlier results obtained in analytical pyrolysis studies and to clarify the relationship between the already thermally degraded charred residues and the controlled heating fragmentation taking place during analytical pyrolysis and direct temperature‐resolved mass spectrometry.  相似文献   

16.
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   

17.
This study aimed to further test the method, reported by St Pierre et al. (2009), to develop robust chronologies of deposits in limestone caves through U/Th (Uranium/Thorium or U-Series) dating of soda straw stalactites. The chronology of fossil bearing deposits at Blanche Cave was further constrained with thermal ionisation mass spectrometry (TIMS) U/Th dating of 17 additional soda straw stalactite samples, and results were compared to recalibrated 14C ages of charcoal. The results support the assertion that soda straw stalactites can provide ages close to the time of sediment deposition and may be used as reliable chronological markers, particularly for periods reaching or beyond the radiocarbon dating limit. The application of an enhanced cleaning technique facilitated the reduction of detrital Th in samples, significantly increasing age accuracy and precision. Additionally U/Th age accuracy and precision was increased through the application of site-specific measured U/Th ratios to correct for the detrital 230Th component in samples.  相似文献   

18.
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   

19.
Australia’s constant experimentation with electoral system design, and its effects on voter behaviour, have been consistent themes in the Australian Journal of Political Science and its predecessor, Politics, for half a century. This article examines this research in the context of three areas: electoral institutions; election campaigns; and voter behaviour. Three distinct stages in the research are identified, starting with basic fact-gathering, then progressing to the application of rigorous methods and evidence to real-world questions. In the third stage, scholarly attention has been devoted to placing Australia within a comparative framework. An underlying theme in the research is Australian exceptionalism in electoral politics.  相似文献   

20.
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   

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