30 resultados para lithics


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Archaeological excavations carried out in the archaeological site of São Pedro (Southern Portugal) revealed a Chalcolithic settlement occupied in different moments of the 3rd millennium BC. The material culture recovered includes different types of materials, such as ceramics, lithics and metals. The later comprises about 30 artefacts with different typologies such as tools (e.g. awls, chisels and a saw) and weapons (e.g. daggers and arrowheads) mostly belonging to the 2nd and 3rd quarter of the 3rd millennium BC. In the present work the collection of chalcolithic metallic artefacts recovered in São Pedro was characterized. Analytical studies involved micro energy dispersive X-ray fluorescence spectrometry (micro-EDXRF) to determine elemental composition, together with optical microscopy and Vickers microhardness testing for microstructural characterisation and hardness determination. Main results show copper with variable amounts of arsenic and very low content of other impurities, such as iron. Moreover, nearly half of the collection is composed by arsenical copper alloys (As > 2 wt.%) and an association was found between arsenic content and typology since the weapons group (mostly daggers) present higher values than tools (mostly awls). These results suggest some criteria in the selection of arsenic-rich copper ores or smelting products. Furthermore, after casting an artefact would have been hammered, annealed and sometimes, finished with a hammering operation. Additionally, microstructural variations in this collection reveal somewhat different operational conditions during casting, annealing and forging, as expected in such a primitive metallurgy. Moreover the operational sequence seems to be used to achieve the required shape to the object, rather than to intentionally make the alloy harder. Overall, this study suggests that Chalcolithic metallurgists might have a poor control of the addition of arsenic and/or were unable to use this element to increase the hardness of tools and weapons. Finally, the compositions, manufacturing processes and hardness were compared to those from neighbouring regions and different chronological periods.

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Ce mémoire traite de l’utilisation des matières premières lithiques telle que représentée sur les sites préhistoriques de la Moyenne-Côte-Nord du Golfe du Saint-Laurent, au Québec. Cette étude régionale se base sur la réanalyse d’un nombre important de collections archéologiques et accorde une grande importance à l’identification et à la description des matières premières utilisées. Un matériau d’origine locale, le Chert de la Minganie, y occupe une place particulière. L’importance de ce matériau pour la préhistoire régionale était jusqu’ici virtuellement inconnue. Suite à nos analyses, un inventaire complet des matières premières utilisées est mis sur pied. Ces données mettent en évidence un certain nombre de comportements. Principalement, nous identifions deux ensembles qui illustrent la présence de territoires attribuables à la répartition de groupes amérindiens subrégionaux (bandes). Finalement, à travers l’utilisation des ressources lithiques, les liens qui rattachent les groupes de notre région d’étude à ceux de la péninsule du Québec-Labrador sont illustrés.

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Les assemblages lithiques dominent la plupart des sites archéologiques du Nunavik et constituent ainsi une véritable mine d’informations. Le nombre limité de travaux sur les matériaux de la côte est de la baie d’Hudson, nous a amené à nous pencher sur une source présente dans ce secteur. Notre objectif était alors de caractériser la matière première provenant de cette formation géologique, le chert Nastapoka. Pour ce faire, nous avons choisi la technique de fluorescence aux rayons X. Les résultats ont permis de constater, en plus des observations macroscopiques, la nature très variable de ce chert présentant une signature chimique complexe. Pour compléter le portrait, nous avons évalué l’utilisation du chert Nastapoka par les Paléoesquimaux par une comparaison d’analyses technologiques déjà effectuées sur les sites GhGk-4, GhGk-63 et IcGm-5. Cet examen a révélé que l’évolution des stratégies d’exploitation des matériaux lithiques dans cette région appui le continuum culturel Prédorsétien-Dorsétien observé ailleurs.

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This paper explores the roles played by local collectors, often little-known or rarely remembered, in the compilation of Britain’s Earlier (Lower and early Middle) Palaeolithic record, with reference to the work of C.E. (Charles) Bean at the Lower Palaeolithic site of Broom, and the activities of George Smith and Llewellyn and Mabel Treacher in the Middle Thames Valley. Their collecting practices, publication records, and archaeological knowledge and insights are reviewed, and their impacts assessed with reference to the activities of other contemporary collectors, and the regional archaeological records of the south-west and the Middle Thames. Their archives demonstrate that while the key sites and artefact assemblages sampled by Bean, Smith and the Treachers would not otherwise have been unknown, their work left important legacies in terms of rich artefact assemblages, site archives (Bean), and the long-term monitoring of key sites and fluvial terraces.

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Recent work on a sample of the chipped stone from one of the late Mesolithic shell midden sites on the Inner Hebrides island of Oronsay has shown that the assemblage was created using bipolar and platform technologies, with an unexpected element of narrow blade technology shown in cores and core trimming elements, suggesting that there may have been links between this classic ‘Obanian’ assemblage and the more typical Mesolithic narrow blade technology. Findings raise questions about the relationship of settlement on the island to Mesolithic settlement rounds and to the transition to the Neolithic.

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At various times during the Quaternary, north-eastern England was a zone of confluence between dynamic ice lobes sourced from the Pennines, northern Scotland, the Cheviots, and Scandinavia. The region thus has some of the most complex exposures of Middle to Late Pleistocene sediments in Britain, with both interglacial and glacial sediments deposited in terrestrial and marine settings. We investigated sedimentary sequences exposed on the coastline of County Durham at Warren House Gill, and present a new model of British and Fennoscandian Ice Sheet interaction in the North Sea Basin during the Middle Pleistocene. The stratigraphy at Warren House Gill consists of a lower diamicton and upper estuarine sediments, both part of the Warren House Formation. They are separated from the overlying Weichselian Blackhall and Horden tills by a substantial unconformity. The lower diamicton of the Warren House Formation is re-interpreted here as an MIS 8 to 12 glaciomarine deposit containing ice-rafted lithics from north-eastern Scotland and the northeast North Sea, and is renamed the ‘Ash Gill Member’. It is dated by lithological comparison to the Easington Raised Beach, Middle Pleistocene Amino Acid Racemisation values, and indirectly by optically stimulated luminescence. The overlying shallow subaqueous sediments were deposited in an estuarine environment by suspension settling and bottom current activity. They are named the ‘Whitesides Member’, and form the uppermost member of the Warren House Formation. During glaciation, ice-rafted material was deposited in a marine embayment. There is no evidence of a grounded, onshore Scandinavian ice sheet in County Durham during MIS 6, which has long been held as the accepted stratigraphy. This has major implications for the currently accepted British Quaternary Stratigraphy. Combined with recent work on the Middle Pleistocene North Sea Drift from Norfolk, which is now suggested to have been deposited by a Scottish ice sheet, the presence of a Scandinavian ice sheet in eastern England at any time during the Quaternary is becoming increasingly doubtful.

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Os solos de terra preta arqueológica são ricos em matéria orgânica, contêm fragmentos cerâmicos e artefatos líticos e apresentam nutrientes em concentrações mais elevadas do que outros tipos de solos. Com o intuito de contribuir com informações sobre concentrações de micronutrientes disponíveis em solos de terra preta, foram avaliadas através de extrações químicas sequenciais, a distribuição e disponibilidade de Cu, Fe, Mn e Zn em um perfil de terra preta arqueológica no município de Juruti, estado do Pará. As maiores concentrações de Cu, Fe, Mn e Zn no perfil são encontradas na fração residual. Este estudo mostrou que ferro, manganês e zinco são preferencialmente disponíveis a partir das frações, associados aos óxidos de Fe-Mn, variando de 1265,39 a 1818,12 mg kg-1, 0,83 a 48,51 mg kg-1 e 1,92 a 12,05 mg kg-1, respectivamente, e o cobre a partir da matéria orgânica, variando de 0,13 a 0,45 mg kg-1.

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Este trabalho apresenta os resultados da aplicação de métodos geofísicos no salvamento arqueológico em três sítios no estado do Pará: Bittencourt, localizado em Abaetetuba; Jambuaçu, localizado em Moju; e Jaburu, localizado em Almeirim. Os métodos utilizados foram Magnetometria, Cintilometria e Radar de Penetração no Solo (GPR). As medidas magnéticas foram utilizadas para indicar os locais para escavação. O GPR foi usado para confirmar as anomalias detectadas pelas medidas magnéticas e proporcionou a diminuição de erros cometidos quando se identificam anomalias magnéticas que não são causadas por feições arqueológicas. As medidas de cintilometria foram usadas para tentar mapear os solos de Terra Preta Arqueológica (TPA) através da radiação gama natural do solo. Os locais indicados para escavação pela magnetometria e GPR possibilitaram a descoberta de materiais arqueológicos como cerâmica, louça, lítico e ferro. Os resultados obtidos com a cintilometria foram satisfatórios, mostrando haver relação entre as medidas mais baixas de cintilometria e as áreas com maior espessura de TPA. A metodologia geofísica utilizada demonstrou eficiência e rapidez sem causar impactos destrutivos nos sítios.

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The Thrace Basin is the largest and thickest Tertiary sedimentary basin of the eastern Balkans region and constitutes an important hydrocarbon province. It is located between the Rhodope-Strandja Massif to the north and west, the Marmara Sea and Biga Peninsula to the south, and the Black Sea to the est. It consists of a complex system of depocenters and uplifts with very articulate paleotopography indicated by abrupt lateral facies variations. Its southeastern margin is widely deformed by the Ganos Fault, a segment of the North Anatolian strike-slip fault system . Most of the Thrace Basin fill ranges from the Eocene to the Late Oligocene. Maximum total thickness, including the Neogene-Quaternary succession, reaches 9.000 meters in a few narrow depocenters. This sedimentary succession consists mainly of basin plain turbiditic deposits with a significant volcaniclastic component which evolves upwards to shelf deposits and continental facies, with deltaic bodies prograding towards the basin center in the Oligocene. This work deals with the provenance of Eocene-Oligocene clastic sediments of the southern and western part of Thrace Basin in Turkey and Greece. Sandstone compositional data (78 gross composition analyses and 40 heavy minerals analyses) were used to understand the change in detrital modes which reflects the provenance and geodinamic evolution of the basin. Samples were collected at six localities, which are from west to est: Gökçeada, Gallipoli and South-Ganos (south of Ganos Fault), Alexandroupolis, Korudağ and North-Ganos (north of Ganos Fault). Petrologic (framework composition and heavy-mineral analyses) and stratigraphic-sedimentologic data, (analysis of sedimentologic facies associations along representative stratigraphic sections, paleocurrents) allowed discrimination of six petrofacies; for each petrofacies the sediment dispersal system was delineated. The Thrace Basin fill is made mainly of lithic arkoses and arkosic litharenites with variable amount of low-grade metamorphic lithics (also ophiolitic), neovolcanic lithics, and carbonate grains (mainly extrabasinal). Picotite is the most widespread heavy mineral in all petrofacies. Petrological data on analyzed successions show a complex sediment dispersal pattern and evolution of the basin, indicating one principal detrital input from a source area located to the south, along both the İzmir-Ankara and Intra-Pontide suture lines, and a possible secondary source area, represented by the Rhodope Massif to the west. A significant portion of the Thrace Basin sediments in the study area were derived from ophiolitic source rocks and from their oceanic cover, whereas epimetamorphic detrital components came from a low-grade crystalline basement. An important penecontemporaneous volcanic component is widespread in late Eocene-Oligocene times, indicating widespread post-collisional (collapse?) volcanism following the closure of the Vardar ocean. Large-scale sediment mass wasting from south to north along the southern margin of the Thrace Basin is indicated (i) in late Eocene time by large olistoliths of ophiolites and penecontemporaneous carbonates, and (ii) in the mid-Oligocene by large volcaniclastic olistoliths. The late Oligocene paleogeographic scenario was characterized by large deltaic bodies prograding northward (Osmancik Formation). This clearly indicates that the southern margin of the basin acted as a major sediment source area throughout its Eocene-Oligocene history. Another major sediment source area is represented by the Rhodope Massif, in particolar the Circum-Rhodopic belt, especially for plutonic and metamorphic rocks. Considering preexisting data on the petrologic composition of Thrace Basin, silicilastic sediments in Greece and Bulgaria (Caracciolo, 2009), a Rhodopian provenance could be considered mostly for areas of the Thrace Basin outside our study area, particularly in the northern-central portions of the basin. In summary, the most important source area for the sediment of Thrace Basin in the study area was represented by the exhumed subduction-accretion complex along the southern margin of the basin (Biga Peninsula and western-central Marmara Sea region). Most measured paleocurrent indicators show an eastward paleoflow but this is most likely the result of gravity flow deflection. This is possible considered a strong control due to the east-west-trending synsedimentary transcurrent faults which cuts the Thrace Basin, generating a series of depocenters and uplifts which deeply influenced sediment dispersal and the areal distribution of paleoenvironments. The Thrace Basin was long interpreted as a forearc basin between a magmatic arc to the north and a subduction-accretion complex to the south, developed in a context of northward subduction. This interpretation was challenged by more recent data emphasizing the lack of a coeval magmatic arc in the north and the interpretation of the chaotic deposit which outcrop south of Ganos Fault as olistoliths and large submarine slumps, derived from the erosion and sedimentary reworking of an older mélange unit located to the south (not as tectonic mélange formed in an accretionary prism). The present study corroborates instead the hypothesis of a post-collisional origin of the Thrace Basin, due to a phase of orogenic collapse, which generated a series of mid-Eocene depocenters all along the İzmir-Ankara suture (following closure of the Vardar-İzmir-Ankara ocean and the ensuing collision); then the slab roll-back of the remnant Pindos ocean played an important role in enhancing subsidence and creating additional accommodation space for sediment deposition.

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Durch den Straßenbau an der Bundesstraße B3a veranlasst, wurden im Zeitraum vom 13.08.2007 bis zum 07.12.2007 archäologische Untersuchungen im Bereich der Streckenkilometer 19 bis 22 durch die Firma Archbau Essen, unter Kontrolle des Landesamtes für Denkmalpflege Hessen und der Kreisarchäologie Wetteraukreis durchgeführt. Bei km 19 wurde dabei eine Siedlung mit angrenzendem Gräberfeld aus der Linienbandkeramik (im Folgenden als LBK bezeichnet) festgestellt. Daneben ergaben sich eine Bestattung und ein Erdwerk der Michelsberger Kultur, Grubenkomplexe und ein Bronzehort aus der Urnenfelderkultur sowie eine mittelalterliche Straße.Heute liegt die Fundstelle Friedberg B3a km 19 in der südlichen Wetterau 30 km nördlich von Frankfurt am Main in Hessen an der Wetter 140 m über NN und gehört zum Wetteraukreis. rnDie 21 ha messende Ausgrabungsfläche umfasste insgesamt 344 Befunde. Die Identifikation der bandkeramischen Strukturen erfolgte hierbei vorwiegend durch die vergesellschaftete Keramik. Von zentraler Bedeutung sind die fünf Hausgrundrisse A bis E im nördlichen Sektor der Fundstelle, wobei die Präsenz zahlreicher „Dreipfostenriegel“ sowie die Nordost-Südwest Ausrichtung der Strukturen als Belege für eine Zeitstellung innerhalb der LBK angesehen werden. Über die Korrespondenzanalyse der bei den Siedlungsstrukturen angetroffenen Keramik konnte darüber hinaus eine Abfolge von Hausgenerationen erstellt werden. Daneben existierten eine Reihe weiterer Befunde von LBK-zeitlichen Pfostenstellungen, bei denen es sich um Zäune oder Palisaden gehandelt haben könnte. Südwestlich dieser Hausgrundrisse wurde bei den Ausgrabungen eine Grabenstruktur geschnitten, für die eine Funktion als Einfassung der bandkeramischen Siedlungsstrukturen möglich ist. Südlich dieser Grabenstruktur konnten sechs Hockerbestattungen der LBK festgestellt werden. Die räumliche Anordnung im Bereich der westlichen Grabungsgrenze lässt den Schluss zu, dass es sich hierbei um ein Gräberfeld handelt, welches bisher nur zu einem geringen Teil ergraben wurde. Ein Zusammenhang zu den Hausgrundrissen A bis E kann erwogen werden. Der nördliche Sektor der Fundstelle umfasste außerdem zahlreiche Grubenbefunde der LBK sowie einige Grubenkomplexe, wobei letztere als Lehmentnahmegruben anzusprechen sind. Abschließend soll hier noch auf die Existenz zweier bandkeramischer Öfen, darunter ein Grubenofen, im Südosten von Friedberg B3a km 19 hingewiesen werden. rnDen mit Abstand größten Anteil am bandkeramischen Fundmaterial aus Friedberg B3 km 19 hatte die Keramik mit 3428 Elementen. An Steingeräten konnten nur 12 Silices sowie 4 Beile und 14 Mahlsteine über die Typologie und die vergesellschaftete Keramik in die LBK eingeordnet werden. Bei den Knochengeräten zeigte sich ein einzelner beschädigter Kamm. Der Fokus der Analysen des bandkeramischen Fundmaterials aus Friedberg B3a km 19 lag auf der Keramik und deren Auswertung innerhalb von Seriation und Korrespondenzanalyse. Um den Untersuchungen mehr Validität zu verleihen und eine optimale Einordnung zu erreichen, wurden die Keramik-Daten aus Friedberg B3a km 19 mit anderen Datensätzen aus Südhessen kombiniert. Dabei war nicht nur die räumliche Nähe der Fundstellen entscheidend, sondern auch die stilistisch-typologische Nähe der Inventare. In Friedberg B3a km 19 waren die Phasen nach Meier-Arendt von einem frühen III bis zum Ende der Phase V anwesend. Phase II kann nur als marginal angesprochen werden. Es ließ sich kein Übergang zum Mittelneolithikum fassen. Nach der Interpretation aller relativchronologischer Daten könnte es sich in Friedberg B3a km 19 um eine Hausentwicklung mit sieben Phasen à 25 Jahren über 175 bis zu 200 Jahren handeln, die eine kontinuierliche Belegung des Platzes von der mittleren bis zum Ende der jüngsten LBK beschreibt. Insgesamt pflegt sich die Fundstelle Friedberg B3a km 19 so in die bandkeramische Siedlungslandschaft der südlichen Wetterau ein.