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51.
There is an increasing use of palynological data to infer prehistoric agricultural activity. The uncritical acceptance of the technique of pollen analysis by archaeologists and palynologists is questioned. Attention is focussed upon the nature of clearance activity and problems of its inference from pollen spectra; the spatial distribution of palaeoenvironmental sites; and the proximity of such sites to those of prehistoric activity. The resolution apparent in peat and lake sediment pollen profiles together with problems of dating and temporal inference, are examined. In response to a perceived lack of formalization in palynological research, some simple models of clearance activity are presented. The complexity involved in environmental reconstruction is emphasized by reference to the use of supplementary data to augment the orthodox pollen record.  相似文献   
52.
The construction date of the medieval manor house at Clevedon Court has long been said to be ‘c. 1320’, but no explanation or justification has ever been published. Stylistic, documentary and archaeological evidence is assembled to show that, following three distinct building phases, the house was completed during the decade ending in 1320. Analysis of the development of reticulated tracery helps to determine the date of the iconic chapel window. Other elements of the medieval house are considered and explained.  相似文献   
53.
The thermoluminescence dating method was applied to 77 heated flints from the Mousterian layers of Hayonim Cave in order to provide a precise TL-based chronology for this important Levantine sequence. A detailed dosimetric study was performed by using 76 dosimeter capsules and revealed strong spatial dose-rate variations. In parallel, Fourier transform infrared spectrometry enabled the identification of various mineral assemblages in the sediments of the cave and to localize the boundaries of these assemblages. By comparing these two data sets, it is shown that low dose-rate values (∼500 μGy/a) are systematically recorded in areas where the calcite-dahllite (CD) assemblage is preserved, whereas higher values (up to 1300 μGy/a) are associated with the leucophosphite, montgomeryite, variscite and siliceous aggregates (LMVS) assemblage. The dosimetric and mineralogical information was combined in order to assess, where possible, the dose-rate experienced by each flint during its burial. Some of the flint samples analyzed were too close to mineral assemblage boundaries and were therefore discarded. This rigorous selection led to TL ages ranging from 230 to 140 ka for the lower part of the Mousterian sequence (layers F and Lower E), which contains lithic industries characterized by blade production using the laminar method.  相似文献   
54.
More than 40 logboats are known from the Czech Republic, and at least 20 are preserved in repositories or regional museums (seven in Moravia, 13 in Bohemia). Two further vessels remain in situ. Many logboats are known from neighbouring countries, but until recently vessels from the Czech Republic have not attracted the same research interest. Only five Czech vessels (two from Bohemia and three from Moravia) have been dated by absolute methods. Several more have been assigned tentative dates on the basis of context or close similarity to other dated vessels. This article presents a summary of current evidence. © 2009 The Author  相似文献   
55.
Under certain environmental conditions, post-depositional diagenetic loss of bone collagen can severely reduce the number of bones from a particular archaeological site that are suitable for stable isotopic analysis or radiocarbon dating. This study examined nearly 300 bones from 12 archaeological sites across southern England known to yield poor or variable preservation to try to identify one, or more, pre-screening technique(s) that would indicate suitable collagen preservation for radiocarbon dating. The most reliable method was shown to be the percent nitrogen (%N) of whole bone powder, which has an 84% chance of successfully predicting whether or not a bone will yield sufficient (i.e. >1% weight) collagen for dating.  相似文献   
56.
This paper presents new AMS radiocarbon dating results of six ungulate bones from the current excavation of Isturitz Cave, France, layer C 4c4. The assemblage from this layer exhibits a suite of traits closely aligned with the Early Aurignacian, but with some aspects that bear strong similarities with the Protoaurignacian, with possible in situ technological transformation. Accurate and precise dating of the late Middle Palaeolithic and the early Upper Palaeolithic periods is critical to our understanding of the possible relationship between final Neanderthals and early modern humans in Europe. As such, a rigorous set of sample selection and evaluation protocols was developed and used in this research. Among these, only cutmarked bones were selected and a total of 31 targets were made, giving a weighted average of 37,180 ± 420 BP for this assemblage and providing a terminus ante quem for the ornaments, decorated artefact and amber pendants beneath it. The implications and importance of these results to debates concerning the chronological relationship between the Châtelperronian, Protoaurignacian and Early Aurignacian and associated debates regarding hominin dispersal, interaction and the timing of technical and cultural innovations are discussed.  相似文献   
57.
A set of 104 independently dated archaeomagnetic directions was used to extend the U.S. Southwest reference curve back to 375 cal BC and to calculate isolated mean VGPs centered on 960 cal BC and 2390 cal BC. Prior to this study, most U.S. Southwest reference curves extended to only ca. AD 585. This study employed Sternberg’s moving window technique with variably sized windows, rather than fixed windows, to smooth the dataset into a continuous curve. The size of each averaging window was determined by the density of data captured by the window, such that each window had a minimum data density of 5.0 and a minimum window size of 50 years. This approach differs from previous studies in the U.S. Southwest, which have applied a uniformly sized averaging window to a dataset regardless of the temporal distribution of the data.  相似文献   
58.
A new sedimentary morphogenic analysis was carried out at the Divje babe I Paleolithic site to determine paleotemperatures for Late Pleistocene deposits (around 80,000–40,000 BP) and to discover hiatuses in the sedimentary sequence. The Divje babe I paleotemperature record is based on the relative abundance of congelifracts in a 280 cm thick sedimentary sequence. Congelifracts are clasts whose morphogenesis is directly associated with post-depositional frost wedging. The Divje babe I paleotemperature record compares well with global GRIP (Summit) and other regional paleotemperature records for the Late Pleistocene. Comparisons are supported by ESR dates from the Divje babe I site. Two significantly cool climate phases were identified in the Divje babe I record. The older cool phase was placed between 67,000 BP and 62,000 BP and the second, younger cool phase was placed between 61,000 BP and 58,000 BP (both Middle Würmian) according to correlations with the GRIP record. The main disadvantage with the Divje babe I paleotemperature record is missing data. The sequence of cave sediments is not complete in Divje babe I due to breaks in sedimentation. Two reliable and two assumed hiatuses were identified in the studied sedimentary sequence.  相似文献   
59.
2003年2月,云南省文物考古研究所为配合三峡工程建设,对位于重庆万州区武陵镇的中嘴遗址进行了考古发掘。本次发掘的遗存以隋唐时期为主,出土了陶器、瓷器以及其他遗物,从中透射出渔业活动是当时当地居民生产生活的一个重要方面,同时也可看到当地文化与周边文化的交流。  相似文献   
60.
The Aterian has a huge geographic extension covering all North Africa, although it was not supposed to exist in the mountain ranges of the central Sahara. Its chronological context is not yet definitively determined and it is still difficult to say whether the Aterian tools are technological, typological, functional, or chronological markers. Recent surveys and excavations at Uan Tabu and Uan Afuda, two rock-shelters located in the central Tadrart Acacus, provide the first chronological, environmental and archaeological indications on this Late Pleistocene human occupation in the area. The lack of organic matter led us to perform OSL and TL analyses on sand. L'Atérien a une énorme extension géographique qui couvre tout le Nord de l'Afrique, tandis qu'on ne pensait pas qu'il existait dans les montagnes du Sahara central. Son contexte culturel n'est pas définitivement déterminé et il est encore difficile de dire si les instruments atériens sont des indicateurs téchnologiques, typologiques, fonctionels ou culturels. Reconnaissances et fouilles récentes à Uan Tabu et Uan Afuda, deux abris situés dans l'Acacous central, fournissent les premières indications sur la chronologie, l'environnement et l'archéologie de l'Atérien dans la région. L'absence de la substance organique, nous a porté à faire des déterminations OSL et TL sur les sables.  相似文献   
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