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91.
江西仙人洞遗址两万年前陶器的年代研究   总被引:1,自引:0,他引:1  
陶器的出现使得人类生存和社会行为发生了重要转变。我们对江西万年仙人洞遗址出土陶器进行了年代研究、对陶片和碳十四测年样品层位关系开展地层显微结构分析,结果显示遗址出土最早的陶片年代为距今19,000~20,000年,比东亚和其他地区的陶器早了2000~3000年。洞穴内遗存证明这些陶器是在末次冰盛期由采集狩猎者所制造,可能被用做炊煮器。说明陶器在农业出现以前一万年甚至更早就被制造和使用了。  相似文献   
92.
One of the largest and best known sites of the Central European Gravettian is the Kraków Spadzista site. This article summarizes archaeological, palaeontological, and zooarchaeological data from the site, obtained in the course of more than 40 years of excavations and studies. The site is known mainly from the discovery of the large mammoth bone accumulation in trench B. During field work conducted in a few trenches located close to this assemblage, numerous human artifacts and faunal remains were found. On the basis of analyses of lithic materials, faunal remains, and radiometric data it is concluded that the Krakow Spadzista site was frequently re-occupied during a few weeks or months, by groups of Gravettian hunters in the period 24–22,000 rcyBP This short-term camp site was related to mammoth hunting. The analysis allowed identification of three possible activity zones, characterized by the presence of different groups of flint tools, fireplaces, and different faunal assemblages: a camp area, a lithic workshop, and an animal-processing area, besides the well known accumulation of mammoth bones.  相似文献   
93.
The debate about the complex issues of human development during the Middle to Upper Palaeolithic transition period (45–35 ka BP) has been hampered by concerns about the reliability of the radiocarbon dating method. Large 14C anomalies were postulated and radiocarbon dating was considered flawed. We show here that these issues are no longer relevant, because the large anomalies are artefacts beyond plausible physical limits for their magnitude. Previous inconsistencies between 14C radiocarbon datasets have been resolved, and a new radiocarbon calibration curve, IntCal09 (Reimer et al., 2009), was created. Improved procedures for bone collagen extraction and charcoal pre-treatment generally result in older ages, consistent with independently dated time markers.  相似文献   
94.
In 2002, the unexpected discovery of Hellenistic architectural blocks, buried in 8 m of alluvium, found displaced in a former bed of the river of Balkh, brought about a programme of surveys and excavations under the aegis of the French Archaeological Mission in Bactria. The geoarchaeological side of the programme focused on the drawing of a regional geomorphological map then on the identification, mapping and dating of the palaeochannels of the river of Balkh. We established the chronology of several fluvial channel generations by association with archaeological settlements of different eras (Bronze Age, Bactro-Achaemenid period, Kushan period, Islamic period) and with optically stimulated luminescence dating carried out on alluvium deposits. The present riverbed leading up to Aqcha was formed during the Islamic period. We suspect the primary agent of this change in the river channel to, be tectonic activity and the activation of a blind fault crossing the floodplain. We identified a northern Bactro-Achaemenid aqueduct, currently located in the desert area separating the plain of Balkh from the Amu Darya.  相似文献   
95.
Abstract

Within the scope of an interdisciplinary research project to determine the genesis and age of small clusters of oak trees, three soil sections in and three outside oak clusters in an ancient woodland/heath on the Veluwe, central Netherlands, were sampled for palynological analysis. The sections within the clusters show an undisturbed development from the Medieval period onwards, the sections outside the clusters are missing ca. 15 cm because of sod cutting associated with plaggen soil formation. The rate of downward movement of pollen was established, using known dates from the near surroundings.  相似文献   
96.
ABSTRACT

Since a radiocarbon chronology of the Dalton culture in the Southeast was first proposed, several new sites have been dated. I propose a new chronology based on radiocarbon dates from sites in the Dalton Heartland and its eastern periphery using Bayesian statistical models in OxCal and an analysis of the associated diagnostic projectile points. The analyses indicate that the Dalton culture probably evolved from the Clovis or Gainey phenomena about 12,680?cal?BP (ca. 10,700?BP) and lasted at least until ca. 10,400?cal?BP (ca. 9,200?BP), if not several centuries later. I propose early and late Dalton phases that follow changes in how Dalton points were made and resharpened. It appears that the people living to the east of the Heartland followed a different trajectory of projectile point evolution. There, notched points appear about 11,500?cal?BP, while in the Heartland, true notched points do not appear in large numbers until the Graham Cave point over 2,000 years later. The chronologies demonstrate that early, coeval, region-wide cultural changes may not have been the norm. They also raise interesting questions about how people in the Heartland and its eastern periphery interacted.  相似文献   
97.
Caves have yielded some of the most globally important archaeological sequences, but often their interpretation has suffered from assumptions about cave sedimentary processes. Caves contain distinctive sedimentary environments: this has major implications for the understanding of contained archaeological materials. This paper describes and analyses the Holocene sediments in the Haua Fteah, a sequence regarded as essentially continuous by the original excavator. 50 years after it was first excavated, the Haua's Epipalaeolithic to post-Classical chronological range and rich finds make it still the key Holocene archaeological site in North Africa. The reassessment shows, however, that the sequence is strongly discontinuous and this has major implications for the reinterpretation of the site, as the highly-resolved archaeological record is thus likely to reflect a series of brief occupations, rather than continuous human activity. As with many caves, the sedimentary record in the Haua Fteah is an extremely sensitive indicator of environments and processes in the wider landscape. Secure understanding of sedimentary process, from analysis of the highly individual records found in caves, is essential for full understanding of their contained archaeology.  相似文献   
98.
Extensive aggregate extraction in the middle Trent valley, England, has revealed a sequence of Holocene palaeochannels associated with nationally important, and predominantly organic, archaeological remains. This paper reports observations of hyper-acidity (below pH 2), high natural magnetism and metallic sphaerules (framboids) in Holocene palaeochannel sediments at two sites in the middle Trent valley. These properties are associated with high natural remanent magnetism which has allowed the successful palaeomagnetic dating of palaeochannel fills at one of these sites (Hemington). These sediment properties are the result of the formation of ferromagnetic iron sulphides, including griegite, under conditions of high sulphur availability (from groundwater) in the presence of metallic ions and organic matter under low redox conditions, with later oxidation producing the extreme natural acidity through oxidation of disulphide (pyrite). These findings explain why, under certain groundwater conditions, alluvial palaeochannel sediments can carry post-depositional remanent magnetisation and be suitable for palaeomagnetic dating. The low pH may also be beneficial in the initial stage of wood preservation and if the sediments remain waterlogged, but probably not retard decomposition after drainage and acidification, a process that is increasingly being recognised as a threat to archaeological sites in wetland environments.  相似文献   
99.
Luminescence dating techniques have been used extensively for archaeological and geological samples. Such techniques are based on thermally or optically stimulated signals. This paper presents simulations of several luminescence techniques for equivalent dose (ED) estimation for ceramic materials containing quartz. The simulations are carried out using a recently published comprehensive kinetic model for quartz, consisting of 11 electron and hole traps and centers. The complete sequence of the experimental protocols for several thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques are simulated using the same set of kinetic parameters. The specific simulated protocols are: additive dose TL protocol, predose technique (both additive and multiple activation versions), phototransfer protocol, single aliquot regenerative optically stimulated luminescence (SAR-OSL) protocol, and SAR thermoluminescence protocol (SAR-TL). One hundred random variants of the natural samples were generated by keeping the transition probabilities between energy levels fixed, while allowing simultaneous random variations of the concentrations of the 11 energy levels. The relative intrinsic accuracy and precision of the protocols are simulated by calculating the equivalent dose (ED) within the model, for a given natural burial dose of the sample. The intrinsic accuracy of these techniques is estimated by simulating natural irradiation of the samples with a known burial dose, followed by simulation of the luminescence method used to recover the estimated dose ED. The percent difference between the burial dose and the ED value represents the simulated accuracy of the luminescence technique. The relative intrinsic precision of these techniques is estimated by fitting Gaussian probability functions to the ED values obtained with the 100 model variants. It is found that the various techniques can reproduce natural paleodoses in the range 10 mGy–10 Gy with a typical intrinsic accuracy of +1 to 10%. Techniques based on single aliquot protocols were found in general to be more precise than techniques requiring the use of multiple aliquots. In addition, techniques based on interpolation of experimental data were found to be consistently both more precise and accurate than those based on extrapolation of experimental data.  相似文献   
100.
The Middle to Upper Paleolithic transition (MP-UP transition) is considered a major technological and cultural threshold, at the time when modern humans spread “out of Africa”, expanded from the Levant into Europe and possibly into central and northern Asia. The dating of this techno-cultural transition has proved to be extremely difficult because it occurred sometime before 40,000 radiocarbon years before present (14C years BP), which is close to the end of the effective dating range of radiocarbon. Other dating methods such as Thermoluminescence (TL) or Electron Spin Resonance (ESR) are not sufficiently precise to date the recorded archaeological MP-UP transition in the Levant. Here we report a consistent set of stratified radiocarbon ages on freshly excavated charcoal from Kebara Cave, Mt. Carmel (Israel), that span the late Middle Paleolithic (MP) and Early Upper Paleolithic (EUP) This study applied novel strategies to improve sample preparation techniques and data analysis to obtain high-resolution radiocarbon models. From this study it is proposed that the MP-UP transition for this site can be placed immediately after 45,200 ± 700 14C years BP and before 43,600 ± 600 14C years BP or from 49/48 to 47/46 radiocarbon calibrated years before present (years Cal BP).  相似文献   
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