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1.
We report the results of a test excavation of deposits in a limestone cave sub-chamber located beneath the main chamber of Liang Bua, Flores, Indonesia; the discovery site of the small hominin species, Homo floresiensis. Well-preserved remains of extinct Pleistocene fauna and stone artefacts have previously been identified on the surface of a sediment cone within the sub-chamber. Our excavation of the deposits, at the base of the sediment cone in the sub-chamber (to 130 cm depth) yielded only a few fragmentary bones of extant fauna. Uranium/Thorium (U-series or U/Th) dating of soda straw stalactites excavated from 20 to 130 cm in depth demonstrates that the excavated sediments were deposited during the Holocene. Red Thermoluminescence (TL) dating of the sediments at the base of the excavation (130 cm depth) indicates these sediments were last exposed to sunlight at 84 ± 15 ka (thousand years), similar to red TL ages of cave sediments from the main chamber. Together, these results indicate that the surface faunal remains, which are morphologically analogous to Pleistocene finds from the main chamber excavations, were transported to the sub-chamber relatively recently from the main chamber of Liang Bua and probably originated from conglomerate deposits at the rear of the cave and from deposits around the front entrance. There is no evidence for hominin occupation of the sub-chamber, instead it seems to have acted as a sink for cultural materials and fossil remains transported from the surface via sinkholes. Despite the small number of finds from the test excavation, it is possible that more extensive excavations may yield additional transported cultural and faunal evidence at greater depths.  相似文献   

2.
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   

3.
4.
The excavation at Takarkori rock shelter is part of a long-term study of Holocene cultural dynamics in southwest Libya begun in the early 1990s. With a rich Holocene occupation, the area is one of the key spots for reconstruction of human occupation of the last 10,000 years. In this region, similar to the case in the rest of the Sahara, most of the data come from surface investigations at open-air sites, while excavated caves and rock shelters provide just a few. Although less exposed than open-air sites, Holocene archaeological deposits in Saharan caves and rock shelters are characterized by a fairly dynamic nature. Loose sediments, coupled with variability of human occupations and magnitude of natural agents, determine multiple alterations to the archaeological deposits in sheltered sites. In this paper, we present the nature and meaning of the archaeological deposits at Takarkori rock shelter, where a relatively large area has been recently excavated, showing a stratigraphic sequence extending from c. 9,000 to 4,200 BP, unevenly represented by several occupation pulses. In order to sharpen understanding of the development of human occupation at this site, specific procedures for the study and recording of the archaeological deposit have been developed, along with a program of extensive radiocarbon dating. Data from the Takarkori sequence ultimately will be integrated with available published stratigraphies from the Acacus Mountains, with the aim of reviewing the results from past excavations.  相似文献   

5.
Snake Cave (Thailand) is an important site for the study of the evolution in Southeast Asia, leading to a discovery of rich and various faunas, including a human tooth. Fossils of large and small mammals converge to indicate, on the basis of faunal assemblage, a late Middle Pleistocene age for the fossiliferous layers; on the other hand, previous U-series dating of carbonates furnished a lower limit for the fossils of about 130 ky.In order to achieve a better comprehension of the chronology of the cave, the Uranium-series method for absolute age determination has been applied to some carbonates older than those studied previously and to fossils themselves.We used the isochron technique approach to yield valuable ages because spleleothem samples consist in a mixture of calcite and detrital contamination. The results obtained suggest that the main fossiliferous level is older than about 160 ky. The application of the U-series method to tooth samples from this tropical cave leads to erroneous ages, probably because of post depositional groundwater movements.  相似文献   

6.
This paper addresses the issue of how coins are dated, and how coins are then used to provide dates on archaeological excavations. Using examples from Roman archaeology, the author examines how patterns of manufacture, supply, loss and retrieval can impact on the value of those dates. The need to examine coin finds within their stratigraphic context is emphasized, as well as the need for the archaeological numismatist and the excavator to collaborate closely to obtain the best from the data. The paper concludes with an analysis of the impact of sample size on dating.  相似文献   

7.
Archaeological excavations and multidisciplinary studies at the site of Dmanisi (Lesser Caucasus, Georgia) have provided an assemblage of lithic artefacts and numerous palaeontological and human remains in a volcano-sedimentary context dating to the early Lower Pleistocene. The sieving of archaeological sediments from Dmanisi also yielded mineralised botanical macro-remains that were analysed according to a particular protocol. The use of scanning electron microscopy (SEM) allowed the comparison between fossil fruit remains and modern specimens, leading to a precise identification of the earlier. Seed remains recognised by this method belonging to several taxa from the Boraginaceae family as well as to the genus Celtis L., of the Ulmaceae family. The ecological requirements of these taxa suggest the presence of xeric conditions, a result that is in accordance with data obtained by faunal and stratigraphic studies.  相似文献   

8.
At many sites throughout the world rock art paintings have been covered by naturally deposited calcite laminations, which we demonstrate can be individually dated by recently improved uranium-series methods. Here we report the application of multi-collector inductively coupled plasma mass spectrometry to measure the ages for carbonate coatings that bracket red pigment at Lene Hara cave, East Timor, which could be evidence of human painting. These analyses establish the feasibility of dating milligram samples of finely layered calcite deposits associated with archaeological evidence of human occupation. In addition to confirming an age of less then 6300 years for the visible red paintings on the carbonate surface we also report a substantially older age of 24,000 to 29,300 years for a similar, older red pigment lamination providing possible evidence for an earlier painting episode.  相似文献   

9.
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   

10.
We present radiocarbon dates and preliminary micromorphological information from the Neolithic cave site of Cueva del Toro (Antequera, Málaga, Spain). This site has yielded a rich early and late Neolithic archaeological record. The late Neolithic assemblage reflects specialized handcraft activity including in situ ceramic manufacture, textile production, and food processing along with sheep and goat penning, suggesting that the cave occupants and their domestic animals shared the same living space. Until now, dating of the stratigraphic sequence was incomplete, and the function of the combustion activities carried out at the cave remained unclear. New absolute dates from the main late Neolithic domestic activity area, corresponding to the most intense Neolithic occupation of the cave, allow us to place the entire sequence between 5320 and 5170 BP (or 4250–3950 to 2σ Cal BC). Micromorphological results show that many combustion features from this site represent recurrently burnt episodes on sheep/goat stabling deposits all along the sequence, corroborating human-goat/sheep cohabitation. This practice had not been previously documented in southern Spain for such early dates. Our results exemplify the importance of characterizing archaeological deposits at a microstratigraphic scale of observation.  相似文献   

11.
We report on tetrapod (Reptilia, Amphibia, Mammalia, Aves) vertebrates recovered during excavations at Tron Bon Lei rockshelter on the south coast of Alor Island, eastern Indonesia. These include both archaeological specimens recovered from a 1 m² test pit dating from ~21 kya cal BP to the late Holocene, and a modern eastern barn owl deposit recovered nearby. To discern between the depositional processes that accumulated the small numbers of micro- and macrovertebrate remains from the archaeological deposits, the taphonomic signature of the natural assemblage was quantified and compared to the archaeological record. The taphonomic data indicates that the tetrapod archaeofaunal remains are a combination of barn owl predation of microfauna and human predation of larger fauna. This approach provides new information on human-tetrapod interactions on Alor in Wallacea during the late Quaternary, including an apparent increase in cave site use and hunting intensity during the Pleistocene-Holocene transition, sea turtle butchery and probable transport, and extinctions of previously unknown giant to large rat species.  相似文献   

12.
Archaeosediments are deposits with a direct or indirect anthropogenic component. They provide useful information about past human activities and interaction with the environment. When other materials, such as pottery, are present in archaeosediment layers, the combination of TL ages from pottery and OSL ages from sediments can provide complete data about the occupation and evolution of an archaeological setting. In Mesopotamia, tells are mounds formed by the debris of human occupation and the accumulation of muddy sediments mainly due to the decomposition of mud bricks in ancient towns. Many other materials such as pottery fragments, bones and charcoal can be found in the sediment layers. The combination of OSL, TL and radiocarbon ages can be very useful in the case of the Bronze Age Period in Syria, allowing the occupation sequence of such archaeological sites to be reconstructed. Tell Qubr Abu al-’Atiq, is located on the left bank of the Middle Euphrates River (Syria). The archaeological artefacts found in the sediment layers (pottery) collected during excavations in two areas of the site, indicated the occupation of the tell during the Early and Late Bronze Age by typological pottery classification. The radiocarbon ages of charcoal indicate that human occupation fits the archaeological hypothesis, providing an older and maximum occupation period between 2800 and 2300 BC and a younger period between 1400 and 900 BC. OSL dating of sediments shows ages younger than charcoal, while TL ages of pottery are generally older than sediment and charcoal ages. This can be explained as the different materials correspond to different events. The charcoal and pottery correspond to occupation periods, while sediments correspond to the further destruction of the site.  相似文献   

13.
Electron spin resonance (ESR) and mass spectrometric U-series dating has been carried out on teeth recovered from K?lna cave during the excavations of 1961–76. Linear and early uptake (LU and EU) age estimates are similar due to low internal U content of the teeth. In general, ESR ages decrease upward in the section, but teeth from stone-rich (“lumpy”) layers give anomalously young ages, due to uneven dose-rate distribution. Elephant molars also give anomalously low ages, apparently due to self-absorption of gamma dose. Disregarding anomalous data, earliest appearance of Micoquian lithics and last occurrence ofDicerorhinus kirchbergensisin layer 9b is dated to 69±8 ka, which places them near the oxygen isotope stage (OIS) 5a/4 boundary. Neanderthal remains and the latest occurrence of Micoquian lithics in level 7a are dated to 50±5 ka, in good agreement with an uncalibrated radiocarbon date for this level of about 45 ka. The interstadial character of the fauna of this level also agrees with its date which places it in OIS 3. We also report that three stadial/interstadial cycles recognized in the lithological, faunal and palynological record of levels 9b through 7a at Kölna occurred during the timespan from about 70 to 50 ka.  相似文献   

14.
During the restoration of the Radium cinema located in the old Town of Zürich, a stratigraphic sequence of medieval fireplaces came to light. Based on ceramic finds, a preliminary age of about 1000 AD was assigned. In this paper we show the results from archaeomagnetic and radiocarbon dating, which combined with the stratigraphic information yield a better constrain of the period of use of these fireplaces. Whilst the radiocarbon technique continues to be the most widespread methodology for dating young archeological artifacts, archaeomagnetic dating is becoming increasingly more established in Europe thanks to the increased number of available measurements. A Bayesian model on the period of use of these fireplaces was produced with OxCal, by a combination of magnetic and radiocarbon ages, together with the stratigraphic information. The results show that the fireplaces were probably used during 1 to 2 generations (e.g. 20–40 years each), and are in good agreement with the archaeological context of this site. To make use of the magnetic measurements for future reconstructions of the field, we carried out an additional age model using only the radiocarbon and the stratigraphic information. Although some of the structures show large directional scatter due to poor baking in antiquity, the results confirm the trend of the geomagnetic field around 1000 AD.  相似文献   

15.
The remains of a ditched field system dating from the late Iron Age to the early post-Roman period, and two associated corn drying ovens (dating to the 5th–6th centuries AD) were revealed during archaeological excavations at Goldthorpe, South Yorkshire. The site was excavated during 2012 and 2013, during which bulk environmental samples were taken in order to retrieve any surviving botanical remains from deposits associated with the corn drying ovens, and other features across the excavated area. Early post-Roman occupation is under-represented in the archaeological record, especially in northern England, as such human activity and subsistence during this period are currently not well understood. This paper combines evidence for the field system, the physical remains of the corn drying ovens and their associated botanical remains to further understand early post-Roman change and continuity in landscape use and crop production and processing practices.  相似文献   

16.
New excavations have been undertaken at Diepkloof Rock Shelter (DRS; South Africa) since 1999. It is one of the very few sites where Howiesons Poort and Stillbay assemblages can be collected from the same archaeological sequence. These Middle Stone Age techno-complexes are particularly interesting for their affinities with the much younger Later Stone Age facies, and their association with evidence for symbolic behaviour. Establishing their chronology is therefore particularly important for the understanding of the apparition and the evolution of the so-called “modern” behaviours. Data already available suggest ages ranging from 55 to 80 ka for the Howiesons Poort and from 70 to 80 ka for the Stillbay techno-complexes in several South African sites. The thermoluminescence dating undertaken at DRS on 22 stone samples originating from the entire stratigraphic record indicates intervals starting 10–50 ka earlier for these techno-complexes in this site. Possible caveats in the dating process are examined but to the best of our current knowledge must be rejected.  相似文献   

17.
The surface of the floodplain of the Ohio River about 20km southwest of Louisville, Kentucky, is a series of linear ridges and swales that are subparallel to the channel of the river, which here is relatively straight and flows southward. Numerous prehistoric occupational sites are located on these ridges. The sediments that underlie the ridges, which were examined in four archaeological excavations as deep as 8 m, are predominantly sandy silt and silty fine to very fine sand and appear to be mainly the product of overbank deposition from suspended load. Abundant cultural material and occupational sites dating as early as 10,000 years BP are found in the sediments at depths as great as 6·5 m. The fine sediments of the floodplain are underlain by sand and gravel.The context of the cultural materials and the stratigraphy and morphology of the deposits indicate that the ridged deposits began as linear riverside sand and gravel bars. These were succeeded upward by fine-grained overbank deposits in which the ridged morphology was maintained because the overbank silt and fine sand were deposited as prograding elongate bars at high water. As the floodplain ridge built upward, the sedimentation rate decreased and the sand content of the sediments diminished, and as the river channel occasionally shifted, the ridged deposits were built in successive subparallel sequences.Two archaeological consequences are implicit in this depositional model of orderly growth of the floodplain. First, available archaeological data from floodplain segments along other parts of the river should confirm the model; and second, the model should make it possible to search the floodplains of the Ohio River for stratified sites of any desired age.  相似文献   

18.
This study presents a synthesis of the evidence for modern archaeological, and palaeontological bioerosion of vertebrate tissue. It describes the first evidence for the bioerosion of modern, archaeological and fossil bird bones. A new form of bone bioerosion, known as Hackett tunnels, is defined. The bioerosion of vertebrate tissue by cyanobacteria and algae in modern marine and lacustrine environments is also described. Archaeological evidence indicates that the destruction of bone by bioerosion occurs in other terrestrial environments, such as cave deposits and middens. Bone from marine and lacustrine environments that appears to be macroscopically well preserved can have large amounts of microscopic fabric destruction. © 1997 John Wiley & Sons, Ltd.  相似文献   

19.
In many papers different authors was described problem of systematic underestimation of TL ages for sediments older then 100 ka. We presented the results which probably are not significantly rejuvenated. This is another example of the TL dates made in Lublin laboratory which are likely in agreement with the stratigraphic interpretation. In 2002 Kusiak et al. published the TL ages ranging from 200 to 800 ka for the Zahvizdja loess profile in Ukraine. These first promising results of TL dating of so old deposits encouraged us to undertake further studies. In next years were discovered other Ukrainian loess profiles with the Middle and Lower Pleistocene deposits, among others in the Skala Podils’ka, Mamalyha and Vendychany sites. The thermoluminescence dating made for these profiles in the Lublin laboratory gave the next, after Zahvizdja, series of 15 TL ages ranging from 200 to 700 ka. This way we confirmed the possibility of TL dating of the deposits older than 400 ka BP.  相似文献   

20.
Abstract

Geoarchaeological research on the southern coast of Oregon brought to light archaeological evidence of early human occupation in the late Pleistocene. Indian Sands (35CU67) lies on a highly eroded deflated headland on the Oregon coast where previous surveys had found and dated surficial cultural materials as early as 8250 b.p. (uncalibrated radiocarbon years). Prior to excavation of Indian Sands, sediment and stratigraphic analysis, along with radiocarbon and thermoluminescence dates, established the existence of late Pleistocene deposits. The excavations confirmed the presence of buried cultural deposits containing lithic artifacts, charcoal, and fire-cracked rock. Dispersed charcoal from the floor of an artifactbearing level was dated to 10,430 b.p., more than 2000 l4C years older than any other Oregon coastal site.  相似文献   

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