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11.
This paper reviews the results of a long-term research project that used stable isotope analyses (δ13C, δ15N, δ34S) and Bayesian mixing models to better model the chronology for a presumed Viking Age cemetery at Hofstaðir, near Lake Mývatn in north-east Iceland. δ13C and radiocarbon dating indicated that many of the individuals consumed a large amount of marine protein, which results in a marine reservoir effect (MRE), making ages older than expected. In addition to the MRE, geological activity in the region has the potential to introduce massive quantities of radioactive ‘dead’ carbon into the freshwater system, resulting in a very large freshwater reservoir effect (FRE) that can offset radiocarbon ages on the order of a few thousand years. The radiocarbon dates of organisms that derive an unknown proportion of their carbon from both marine and freshwater reservoirs are extremely difficult to ‘correct’, or, more appropriately, model. The research not only highlights the complexities of dealing with multiple reservoirs, but also how important it is to develop models that are temporally and geographically relevant to the site under study. Finally, it shows how this data can be used to inform the development of chronological models for refining the dating for archaeological activity. 相似文献
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Wouter A. Marra Liesbeth van de Grint Koko Alberti Derek Karssenberg 《Journal of Geography in Higher Education》2017,41(2):213-229
Field courses are essential for subjects like Earth Sciences, Geography and Ecology. In these topics, GIS is used to manage and analyse spatial data, and offers quantitative methods that are beneficial for fieldwork. This paper presents changes made to a first-year Earth Sciences field course in the French Alps, where new GIS methods were introduced. Students use GIS in preparation to explore their research area using an elevation model and satellite images, formulate hypotheses and plan the fieldwork. During the fieldwork, a pilot group managed their field-observations using GIS and made digital maps. Students praise the use of quantitative digital maps in the preparation. Students made use of the available techniques during the fieldwork, although this could be further intensified. Some students were extra motivated due to the technical nature as well as the additional analytical possibilities. The use of GIS was experienced as a steep learning curve by students, and not all staff members are confident in supervising students using GIS, which calls for a sufficient preparation and training of both students and staff. The use of GIS adds abstract analyses and quantitative assessment, which is a complementary learning style to fieldwork that mostly focuses on practical skills. 相似文献
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Marta García-Alonso 《History of European Ideas》2017,43(4):331-344
ABSTRACTFor most interpreters of the philosopher from Rotterdam, his political doctrine is solely a consequence of his religious and moral doctrines, and so an image of Bayle as a political philosopher is not usually presented. To my mind, however, only by analyzing his political doctrine can the extent of his religious proposal be understood. In this article, I intend to show that both the Baylean criticism of popular sovereignty and his rejection of the right of resistance are analyses that are indissociable from the Baylean doctrine of tolerance. The protection of individual freedom of conscience and the defense of a multi-confessional state model, tolerant regarding religious minorities, can only be articulated as historical reality if they rest on the political doctrine of indivisible sovereignty and on the strictest separation between political obedience and religious membership. 相似文献
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Dánae Fiore Marta Maier Sara D. Parera Luis Orquera Ernesto Piana 《Journal of archaeological science》2008
This paper presents the results of chemical analyses of the organic and inorganic fractions of pigment residues found in three archaeological sites located in the Beagle Channel region, Tierra del Fuego, Southern South America. Twenty-one archaeological samples have been analysed through XRD, SEM–EDX, FT-IR and GC–MS in order to characterise their inorganic colouring components and to search for the presence of organic substances used as binders. Lipids found in some samples are considered as potential binders. These organic components are compared to those found in archaeological sediment samples from the same layers where the pigments have been found, in order to search for potential taphonomic contaminations of the latter by the former. Results show that such contaminations are unlikely, hence the lipid contents are deemed of anthropic origin. The pigment sample results are also compared to data from analyses of natural sediment samples collected in several localities of the Beagle Channel in order to search for potential natural pigment sources. Results show that organic and inorganic components of these sediments are not the same than those present in the archaeological pigment samples, hence the pigment raw material sources have not been yet located. All these data provide for the first time evidence of the existence of ancient activities of pigment sourcing and paint preparation with organic binders which range from 6000 BP to 1900 BP in the southernmost region of the planet. 相似文献
16.
Rosa Maria Albert Ruth Shahack-Gross Dan Cabanes Ayelet Gilboa Simcha Lev-Yadun Marta Portillo Ilan Sharon Elisabetta Boaretto Steve Weiner 《Journal of archaeological science》2008
The presence of many phytolith-rich layers in late Bronze and Iron Age deposits at Tel Dor, Israel, are indicative of specific locations where plants were concentrated. Detailed studies of six of these phytolith-rich layers and associated sediments from Tel Dor show that the phytoliths were derived mainly from wild and domestic grasses. The most common domestic grass was the cereal Triticum aestivum (bread wheat). Three of these layers have a microlaminated microstructure, associated dung spherulites and phosphate nodules; characteristics that all point to the phytolith-rich layers having formed from dung in animal enclosures. In two of the layers, the microlaminated structure is absent while dung spherulites and phosphate nodules are present, suggesting that these too originate from dung that was not deposited in an enclosure. The sixth layer is microlaminated but does not contain spherulites. We thus cannot suggest a parsimonious explanation of its observed properties. Concentrations of burnt phytoliths are present in three locations, implying that dung was either burnt in situ or the ashes from burnt dung were redeposited. The transformation of dung accumulations into phytolith-rich layers involves a loss of organic material and hence a significant reduction in sediment volume, which is clearly apparent in the stratigraphy of some of the locations examined. The volume reduction can be observed in the macrostratigraphy and has important implications with regard to macrostratigraphic interpretation. The presence of abundant phytolith-rich layers on the tell has significant implications for the concept of ‘urbanism’ during these periods. 相似文献
17.
Marta Navazo Alvaro Colina Salvador Domínguez-Bella Alfonso Benito-Calvo 《Journal of archaeological science》2008
Microscopy, mass spectrometry and X-ray diffraction methods were used to analyse 415 samples of natural and archaeological flint from Sierra de Atapuerca (Burgos, Spain) in order to define the different types from Neogene and Cretaceous formations in the study area, infer their genetic context and ascertain the supply sources used by hunter-gatherers who exploited this area in the Upper Pleistocene. A statistical classification model was also designed using linear discriminatory analysis and support vector machines which permitted the differentiation of the flint on an age basis. 相似文献
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Efthymia Nikita David Mattingly Marta Mirazón Lahr 《Journal of Anthropological Archaeology》2012,31(4):564-572
Archaeological evidence shows that populations used to transverse the Sahara Desert throughout the Holocene despite the extreme temperatures and the rough physical terrain. The current paper examines whether the desert inhibited extended gene flow among populations by means of cranial morphology as captured by geometric morphometrics. The examined populations include the Garamantes, a group centered in Southwest Libya and largely controlling trans-Saharan trade, and various Egyptian, Tunisian and Sudanese groups dating to the Middle and Late Holocene. The results showed that most inter-population comparisons were statistically significant and therefore all populations appear more or less distant to each other. The Mahalanobis biodistance measure identified four clusters. The first consists of the Garamantes alone, the second includes the populations from Kerma and Gizeh, the third includes the Badari and Naqada, while the fourth consists of the samples from Algeria, Carthago, Soleb and Alexandria. Moreover, the distance of the Garamantes to their neighbors was significantly high and the population appeared to be an outlier. This is attributed to the location of the Garamantes at the core of the desert, indicating that, despite the archaeological evidence, the Sahara Desert posed important limitations to gene flow between the Garamantes and other North African populations. 相似文献