Monte Arci Obsidians: Some More Geochemical Data from EMP-WDS, SEM-EDS and PIXE

We bring new geochemical data on Monte Arci (Sardinia) obsidians from elemental analyses by electron microprobe (EMP) and proton-induced X-ray emission (PIXE). Obsidians from the geochemical groups SA, SB1, SB2 and SC can be sorted out from their major element contents by EMP and from their trace element contents by PIXE. While EMP analysis requires for analysis a few milligrams polished fragment, PIXE is strictly non-destructive. Forty samples were part of a program aimed at the geochemical characterization of Monte Arci secondary sources

Datação por traços de fissão e geocronologia do Plio-Quaternário

A datação por traços de fissão aplicada em estudos do Plio-Quaternário é pouco conhecida no Brasil. O objetivo principal do presente manuscrito, redigido em língua portuguesa, é apresentar e fazer ampla divulgação das potencialidades desta metodologia aos pesquisadores que atuam nesse domínio temporal das ciências da natureza no nosso país. Para tal são apresentados detalhadamente todos os aspectos da datação por Traços de Fissão. São abordados os princípios básicos da datação por Traços de Fissão, a equação da idade, precisão e acurácia, as técnicas analíticas utilizadas em função das particularidades e natureza dos materiais, suas limitações assim como os casos de sucesso. Também são apresentados diversos estudos de caso com exemplos de utilização da metodologia nas variadas áreas de aplicação de pesquisas do Plio-Quaternário, inclusive em arqueologia

Obsidian Economy in the Rio Saboccu Open-Air Early Neolithic Site (Sardinia, Italy)

Integrated provenance/typo-technologic/chaînes opératoires studies on obsidians from Early Neolithic (EN) assemblages are still quite exceptional in the western Mediterranean region. The Rio Saboccu S1-S2 EN dwelling structures (Central-western Sardinia) 14C dated to the last three centuries of the VIth millennium BC provided us with an opportunity to apply such an approach. A comprehensive provenance study of its 1.114 obsidian artefacts was realized through a combined visual/instrumental approach. Elemental compositions were determined mostly by ion beam analysis (PIXE) and by electron microprobe (SEM-EDS). The S1-S2 structures are situated inside the so-called supply zone of the Monte Arci volcanic complex. A technological analysis of the implements revealed a non-opportunistic behaviour in relation to obsidian procurement among the four (SA, SB1, SB2, SC) Monte Arci types locally available in various contexts (from primary to secondary sources). A comparison with other Sardinian EN sites suggests that the human groups settled near the Monte Arci sources might have acted as a ‘filter’ in the first stages of the diffusion of obsidians in Sardinia and possibly elsewhere in the northern Tyrrhenian area

Tendances actuelles dans la caractérisation des obsidiennes pour les études de provenance

Les recherches de provenance des obsidiennes de sites paléolithiques et néolithiques connaissent actuellement une grande expansion, notamment par leur intégration dans les études de chaînes opératoires, qui nécessitent de déterminer l’origine de la matière première de séries importantes de pièces archéologiques. Il existe par ailleurs une forte demande de mesures peu à non destructives et éventuellement à effectuer in situ. D’où un certain nombre de développements méthodologiques récents. Le but de cette contribution est d’en présenter le statut actuel.Sourcing studies involving obsidians from Palaeolithic and Neolithic sites are presently undergoing a period of change, notably in terms of the average number of samples analyzed per project, due largely to their integration into the chaînes opératoires approach of lithic technologies. This can entail working with a large number of artifacts from an archaeological context. There is also an ever-increasing demand to employ quasi non-destructive characterization methods and completely non-destructive methods that eventually could be performed in situ. As such, recent methodological advances have taken several directions. The purpose of this short note is to give an overview of these approaches

Obsidian in the Upper Palaeolithic of Iberia

Sourced from the Tyrrhenian Islands and exchanged over long distances, obsidian was used widely across prehistoric Western Europe. An obsidian core and bladelets from a newly discovered rockshelter site in south-eastern Spain, however, raised the possibility of an unrecognised mainland source of obsidian. EDXRF analysis of the Early Magdalenian finds from La Boja links them to a source 125km to the south-west. The artefacts were discarded during two brief activity phases at the site, indicating that obsidian procurement was integral to the technological choices of the site's users. The specificities of the technocomplex may explain the unique nature of this occurrence.info:eu-repo/semantics/publishedVersio

Flint in its diverse natural occurrences: geo-­‐tools for a better definition of the sourcing of secondary outcrops

International audiencePrecise identification of siliceous geo-resources used during prehistory still poses many problems, and archaeologists make ever-increasing demands for this data. The purpose is to provide a database containing an exact and descriptive identity for each different type of geological flint found within a region. The parameters we have chosen to characterize are the mineralogical composition (by optical microscopy, SEM, microprobe, cathodo-luminescence), microfacies characteristics (identified during microscopy and SEM image analysis), porosity measurements (by image analysis and porosimeter), and the presence and distribution of major and trace elements (using ICP, LA-ICP-MS, XRF, PIXE, Raman and SEM-EDS) at the surface or in the cracks in the matrix

Sourcing lithic raw materials

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Analyse Factorielle Discriminante et Circulation de l’obsidienne préhistorique

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Towards the Hyperboreans : tracing out a parabola of Sardinian obsidian exploitation and distribution during the Neolithic

International audienc