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1.
Results of OSL dating and sedimentary studies from the profile of the low alluvial terrace of the middle Warta River are presented. The samples were dated using the single-aliquot regenera-tive method. Dating was used to establish a timing of the Weichselian Late Glacial events in the river valley environment. Stable conditions on the floodplain are expressed by the deposition of organic-rich series radiocarbon dated at 12 900-12 600 cal BP and 11 600-10 770 cal BP. Samples for OSL dating were collected from the mineral material deposited during the intensification of flood events during the Weichselian decline. The results obtained for the alluvia range from 12.78 ± 0.62 ka b2k to 14.33 ± 0.74 ka b2k. Sedimentological criteria allowed to distinguish between particular flood events. Overestimation of OSL ages is probably a result of rapidity of environmental changes in that time.  相似文献   

2.
This study focuses on the analysis of the structural and textural features of the colluvial (deluvial) deposits in the Suwałki Lake District (NE Poland) and their absolute age. The colluvium has a thickness of up to 150 cm. The dates of the peat under colluvium or lowermost fossil humus-rich horizons point to the ages from 5405±80 BP to 480 BP. Deposition of material at the footslope is a result of a denudation triggered by human action (surface water erosion and tillage erosion) and usually corresponds with the settlement stages. The 14C dating of deposited sediment sometimes indicated to older dates of colluvium then the archaeological evidence available for examined sites. Locally, the overlying fossil humic horizon was older then the lowermost one. The textural features of the colluvial deposits such as: the content of fine fraction, weak sorting and relationship between the mean grain-size (Mz) and the sorting index (σ1) were used to recognize sediment redeposited from the upper part of the slope. Basing on the mineral composition and electrical conductivity of fossil humus horizon it is possible to say whether the soil was degraded or aggraded. These features of the humus-rich horizons occurring between colluvial sediments can be used to explain discrepancy between the radiocarbon dating and archaeological evidence.  相似文献   

3.
Botanical assemblage including charred and mineralized macro plant remains were examined from tell Kedesh in the Upper Galilee, Israel. Flotation samples were collected from various contexts within and outside a large Persian-Hellenistic administrative building complex at tell Kedesh, dated to the 5th to the 2nd century BC, based on the archaeological material. Four AMS radiocarbon dates were obtained on plant macro remains recovered from the flotation samples from the complex. The radiocarbon dates range from the 9th century BC to 17th century AD. The discrepancy among the radiocarbon dates obtained from plant remains and those based on archaeological material can be attributed to bioturbation, including the deep burrowing of harvester ants. The study demonstrates the need for direct radiocarbon dating of the charred plant remains generally assumed to be of ancient origin. This research improves the understanding of depositional and postdepositional processes of plant macro remains and explains their mode of arrival, relevant for the sites with a long occupational history by humans and animals.  相似文献   

4.
The first fission track analyses of detrital apatite grains from the subsurface of the Kaapvaal Craton were utilized to delineate the thermal history for the northern margin of the Witwatersrand Basin, South Africa, where evidence for subsurface thermophilic and hyperthermophilic microorganisms have been discovered. Fission track apatite ages for core samples ranged from 21 to 422 Ma. The trend of decreasing age with increasing depth parallels a trend previously reported for fission track data from surface samples collected from the higher altitude centre and lower altitude margins of the Kaapvaal Craton, South Africa. These new fission track ages are older than the surface samples of equivalent elevation, indicating that the uplift history and/or the geothermal gradient of the centre of the Kaapvaal Craton is distinct from that of its margins. Modelling of one sample collected from a depth of 3.7 km records cooling from 120°C at 75 Ma at a rate of approximately 1.4°C m.y.?1 and reaching present day temperatures at 30 Ma. This modelling result when compared to other apatite fission track dates indicate that this cooling trend followed a 90‐Ma thermotectonic event. The fission track data also indicate that heated fluid migration, which is observed today in this region of the Witwatersrand Basin, was also active in the past in order to explain the greater palaeogeothermal gradient (18 versus 8°C km?1). The fission track results suggest that at approximately 70 Ma only hyperthermophilic microorganisms could have existed at palaeodepths >3.2 km depth in the Witwatersrand Basin, and that the current meso/thermophilic microbial communities living at or beneath the present depth of 1.7 km in the Witwatersrand Basin must have migrated to their current location since 70 Ma. Any hyperthermophilic microorganisms found at the present depths 1.2–3.7 km could be descendents of subsurface hyperthermophiles that colonized the crust since the early Mesozoic to Palaeozoic eras.  相似文献   

5.
Over a period of some 100 years it has gradually been accepted that the human skeletal remains found in the late nineteenth century in ancient gravels at Galley Hill, Kent are not those of early man, but are of much more recent date. This conclusion was finally verified by means of relative (N, F) and absolute (14C) dating. Here we present the results of further analysis of the remains from Galley Hill for their uranium content by a method having general application to the relative dating of fossil human and other mammalian bone.  相似文献   

6.
Around the globe, archaeological settlement pattern survey has brought a new spatial, diachronic, and theoretical vantage to the study of early civilizations. This paper provides a new perspective on the rise and reorganization of complex societies in northern China through the synthesis of 11 years of systematic regional survey in southeastern Shandong Province. Based on our surface findings, we suspect that the agricultural colonization of this coastal region occurred primarily during the later half of the Neolithic and was rapidly followed by the development of a four-tiered settlement hierarchy with two primary centers during the Early Longshan period. We also document the reorganization of this regional system during the Bronze Age, and the eventual political integration of this study area under polities centered to the west (and outside the region surveyed). We argue that southeastern Shandong was not merely a backwater or periphery throughout its history, particularly in regard to the Early–Middle Longshan periods when there were centers of great size. Through our long-term and broad-scale perspective, we provide new evidence of how complex societies arose and changed over millennia in northern China.  相似文献   

7.
Three hominin phalanges were recently identified in old faunal collections attributed to the Late Acheulean (Layer D2) dated to ca. 213 Kya, from Oumm Qatafa Cave (Judean Desert), a site excavated in 1928–1949. In terms of general appearance (colour, patina and adhering sediment), these specimens resembled the fauna with which they were found, but the likelihood of stratigraphic problems especially in old excavations, the presence of 4th millennium b.c. burials in the topmost Layer A at the site and the absence of any mention of Late Acheulean hominin remains in publications relating to the site prompted us to verify that the phalanges were indeed in situ. Osteometric examination showed the phalanges to be indistinguishable from those of Middle Paleolithic Levantine anatomically modern humans (AMHS) as well as Upper Paleolithic and recent populations, thus contributing little to the resolution of their provenance. To further investigate this issue, we compared the elemental composition of the phalanges to that of fauna from the same and overlying archaeological layers using non-destructive laser ablation–inductively coupled plasma mass spectrometry (LA-ICP-MS). The results showed a close resemblance in elemental composition between the phalanges and fauna from Layer D2, implying that they are in situ. This would indicate either an early occurrence of AMHS in the region or the presence of an ancestral archaic Homo. We propose that LA-ICP-MS offers a useful minimally invasive method for provenancing isolated human and faunal remains.  相似文献   

8.
9.
A very accurate archaeological dating of a Roman site in NE Spain (El Vila-sec) was made based on the typology of pottery artifacts. Three different phases were identified with activity ranging from the mid-1st century BC to the early-3rd century AD. Analyses of bricks from kilns at El Vila-sec produced data on their stored archaeomagnetic vector. These data were compared with the secular variation curve for the Iberian Peninsula and the SCHA.DIF.3K regional archaeomagnetic model. Both, the reference curve and the model, produced probability distributions for the final period of use for two kilns from the second archaeological phase that were not used during the third phase. At a 95% confidence level, both time distributions cover a wide chronological range including the presumed archaeological age. Both the Iberian secular variation curve and the SCHA.DIF.3K regional model proved to be suitable models for dating the site, although on their own they do not produce a single unambiguous solution. This archaeomagnetic approach could also be applied to neighbouring archaeological sites that have an imprecise archaeological age.  相似文献   

10.
Journal of Archaeological Research - This paper reviews significant issues related to the fossil hominins from the Altai Mountains of Siberia (Russia), namely Denisovans, Neanderthals, and early...  相似文献   

11.
Extended research covering an area of approximately 300 sq km centered on the ancient metropolis of Aksum has revealed a coherent sequence of development in stone tool production and use spanning most of the last millennium BC and the first millennium AD. It has provided new evidence of the presence of multiple independent lithic traditions in the Pre-Aksumite period, and of Aksumite social and economic organization. This paper summarizes the results of the detailed study of a large corpus of excavated and surface-collected lithics, emphasizing their functional characteristics.
Résumé  De vastes recherches couvrant sur une superficie d’environ 300 kilomètres carrés et concentrées sur l’ancienne métropole d’Aksoum ont mis à jour une série cohérente de développements dans la production et l’utilisation d’outils de pierre au cours du dernier millénaire avant J.C. et du premier millénaire après J.C. Ces recherches ont fourni de nouvelles informations sur la présence de multiples traditions lithiques indépendantes durant la période pré-aksoumite, et sur l’organisation sociale et économique des Aksoumites. Cet article présente les résultats d’une étude détailée portant sur un large répertoire de vestiges lithiques recueillis au cours de fouilles et collectes de surface, et met en exergue leurs caractéristiques fonctionnelles.
  相似文献   

12.
"Theories of trade and migration explain the distribution of individuals among regions based on private good productivities. The theory of local public goods (LPG's) uses collective good consumption economies to explain the size and composition of communities. This essay combines the two theories, to explore regional population heterogeneity and stability. Assuming that individuals must consume and produce in the same jurisdiction, the paper examines the nature of efficient allocations, the tensions between the private and public incentives, the nature of the equilibrium (if any) which migration among jurisdictions will generate, and how such equilibrium will depend on tax rules for sharing the costs of the LPG."  相似文献   

13.
Palaeoenvironmental evidence for the character of lowland cultural landscapes during the last 2500 years in Britain is poorly understood, owing to a combination of an over-reliance on data from upland sequences, and because lowland mires are typically located in positions marginal to areas of settlement and agriculture. This paper presents an attempt to derive environmental evidence for this time period from a lowland context in order to characterise the key periods of change and continuity in the lowlands. The study focuses on mid-Devon, in South West Britain, and uses small pollen sites which are embedded within the historic landscape. The South West is a particularly poor region for lowland environmental data, and has until now been reliant on upland sequences. The results show that continuity, rather than abrupt change, has characterised the landscape from the later Iron Age to the early medieval period (around cal AD 800). There is no palynologically distinct Roman period in the data, contrary to evidence from the high uplands of Exmoor that suggests a decline of the agricultural system during the immediate post-Roman period. Around cal AD 800 there is a change in the agricultural system from predominantly pastoral activities to one that led to relatively high proportions of cereal pollen appearing in the sequences, which is interpreted here as marking the onset of convertible husbandry, a regionally distinct agricultural system which is recorded from AD 1350, but whose origins are not documented. This agricultural system remained in place until the post-medieval period, when the predominant agricultural regime returned to pastoralism around AD 1750. The data clearly show discrepancies between the high uplands and the lowlands, demonstrating the potential hazards of extrapolating upland sequences to lowlands environments.  相似文献   

14.
15.
The role of natural processes in the formation of the Bed I and II sites at Olduvai Gorge (Tanzania) remains the subject of much debate, five decades after their original excavation. Preferred orientation of items is indicative of water disturbance, but compass bearings were not available in Mary Leakey's (1971) study. Using GIS methods, we have vectorized maps from 1960s excavations at Olduvai, and applied a range of statistical techniques to calculate items strike. The GIS analysis suggests strongly preferred orientation patterns in Bed I, and more heterogeneous angular histograms in Bed II. Two complementary lines of evidence support these results. Firstly, modelling of potential mapping errors provides a large interval of confidence for preferred orientation patterns. Second, the GIS study was extended to photographs of the earlier excavations and to maps from recent fieldwork at Olduvai; both yielded patterned arrangement of lithics and bones, and are consistent with results based on the analysis of the 1960s maps, i.e. a large number of the Bed I and II assemblages are preferentially oriented. These results highlight the potential of GIS applications to the analysis of imagery in Stone Age studies, and bear important implications for the understanding of the role of natural agents in site formation processes at Olduvai.  相似文献   

16.
Radiocarbon and U-series methods (230Th/U and 231Pa/235U) for absolute age determination have been applied to some fossil samples from Grotta Juntu, in North Eastern Sardinia (Italy). The remains belong to the endemic deer species Praemegaceros cazioti, which is here represented by an almost complete skeleton. The three dating methods lead to concordant ages of about 7500 years BP, indicating that the skeleton was maintained as closed system after burial. Taking into consideration these results, Praemegaceros cazioti from Grotta Juntu is now the youngest representative of this species in Sardinia.  相似文献   

17.
Looking at Fijian Methodism and its role in discourses on identity in Fiji leads to the question of the relationship between Christianity and the vanua, the complex notion of land so crucial for ethnic Fijians' traditionalistic identity constructions. How is it possible to retain important dimensions of the vanua within a Christian worldview? An attempt to understand this relationship using the example of a Fijian meke makes clear that specific ways of constructing the past are crucial here. A concept of history as a symbolic form renders these ways of constructing the past understandable as historical — and it is exactly this historical character which opens the possibility of establishing a relationship to the Christian God while retaining essential dimensions of the vanua, a possibility which can provide one experiential background for the plausibility of an ethnic interpretation of Christianity.  相似文献   

18.
Numerous local, regional and family historians in the nineteenthand early twentieth century collected oral narrations and conductedinterviews as a form to document information that otherwisemight have never been preserved. Family historians, in particular,not only practiced interviewing relatives for family histories,but also encouraged the practice in how-to-do manuals amongtheir peers. While advocating the practice, family historiansalso reflected about the value of "traditionary evidence" collectedthrough interviews and other means. These reflections by familyhistorians mirrored the discussions about the value of traditionsand memories as historical sources among several professionalhistorians at the time. These reflections were shaped by a modernizedunderstanding of tradition, which combined a reverential approachto the authoritarian element of tradition with a critical approachquestioning the validity of tradition. In this context, oralhistory was both a tool to negotiate the value of traditionand a mirror to the contemporary understanding of tradition.  相似文献   

19.
The Devonian Antrim Shale is an organic‐rich, naturally fractured black shale in the Michigan Basin that serves as both a source and reservoir for natural gas. A well‐developed network of major, through‐going vertical fractures controls reservoir‐scale permeability in the Antrim Shale. Many fractures are open, but some are partially sealed by calcite cements that retain isotopic evidence of widespread microbial methanogenesis. Fracture filling calcite displays an unusually broad spectrum of δ13C values (+34 to ?41‰ PDB), suggesting that both aerobic and anaerobic bacterial processes were active in the reservoir. Calcites with high δ13C values (>+15‰) record cementation of fractures from dissolved inorganic carbon (DIC) generated during bacterial methanogenesis. Calcites with low δ13C values (13C values between ?10 and ?30‰ can be attributed to variable organic matter oxidation pathways, methane oxidation, and carbonate rock buffering. Identification of 13C‐rich calcite provides unambiguous evidence of biogenic methane generation and may be used to identify gas deposits in other sedimentary basins. It is likely that repeated glacial advances and retreats exposed the Antrim Shale at the basin margin, enhanced meteoric recharge into the shallow part of the fractured reservoir, and initiated multiple episodes of bacterial methanogenesis and methanotrophic activity that were recorded in fracture‐fill cements. The δ18O values in both formation waters and calcite cements increase with depth in the basin (?12 to ?4‰ SMOW, and +21 to +27‰ PDB, respectively). Most fracture‐fill cements from outcrop samples have δ13C values between ?41 and ?15‰ PDB. In contrast, most cement in cores have δ13C values between +15 and +34‰ PDB. Radiocarbon and 230Th dating of fracture‐fill calcite indicates that the calcite formed between 33 and 390 ka, well within the Pleistocene Epoch.  相似文献   

20.
The pre-Magdalenian phase of the Côa River Valley open-air rock art is mostly distributed at the boundary between the rocky valley slopes and the floodplain that correspond to the most favourable geomorphological setting for the preservation of pecked and deeply superposed engravings of the most famous artistic phase of the area. The natural vertical panels of the engraved art located at this geomorphological interface have suffered weathering during two cold events of the Lateglacial. They were buried by several colluvial and alluvial deposits. The reconstruction of the sedimentary and archaeological context of the CôaRiver Valley engraving permits a better assessment of the preservation processes and interpretation of Palaeolithic open-air rock art.  相似文献   

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