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LITHOLOGICAL SELECTION IN POLYGENIC GRAVELS OF NOTARCHIRICO (EARLY ACHEULEAN, SOUTHERN ITALY)
No full textThe several human occupations attested at Notarchirico (Venosa, southern Italy) date back to 610-695 ka, among the oldest
ones in Western Europe at the MIS 17/MIS 16 transition.Open-air occupations were at the top or in proximity of polygenic
pebbles/cobbles formed in fluvio-lacustrine environment, which made available various knappable material. Prevalent larger
limestone lithotypes, together with smaller silicified calcarenites (flysch chert), nodular chert (carbonate platform) and
radiolarite (basin) originated from the outer geological units of the Southern Apennine. The technological study of the lithic
assemblages identified pebbles with percussion marks or broken, pebble tools, Large Cutting Tools (bifaces, cleavers, unifacial
tools, pick), cores, flakes, flake-tools and retouched nodules. A selection of archaeological and geological lithic samples was
studied to verify the archaeological hypothesis of the exploitation of local polygenic pebble/cobble lags to produce artefacts, as
well as the hypothesis of lithological selection. Petrographic analysis of samples as such, coupled with thin section microscopy
for geological samples, as well as colorimetric (spectrophotocolorimeter) and geochemical (pXRF) analyses were carried out.
The results show that the lithotypes of the pebble/cobble lags are compatible with those of the artefacts. Moreover, pre and
post depositional black patina due to wetland conditions further prove local exploitation. Preferential use of limestone cobbles,
with some exception, for Large Cutting Tools and silicified calcarenites to produce very small flakes indicate adaptation to local
raw materials. The relative abundance of flysch chert among artefacts, compared to the other chert varieties, is interpreted as
a consequence of its abundance among chert lithotypes. The size/shape of the pebbles/cobbles was the main limiting factor in
the choice of raw materials for lithic artefacts
Chert circulation in Neolithic sites from central-northern Apulia: Gargano mines and secondary sources
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Application of non destructive multiparametric protocol for chert characterisation: preliminary data from apulian neolithic sites
No full textIn last decades, archaeometric research about obsidian sources and circulation in Central Mediterranean area reached good results, despite what happened for other knappable materials. In much detail, archaeometric literature on cherty materials is poor and discontinuous in time and space. Difficulties in unambiguous characterisation to identify distinguishing features of chert for sourcing, makes relatively hard to compare materials from different regions and retrace ancient trade routes. Current archaeological knowledge about the circulation of chert in central Mediterranean Sea identifies Gargano Promontory as one of the main sources. In addition, the Gargano is located along one of the supposed ways of the spread of the Neolithic in Southern Italy, which is the “bridge” of Adriatic islands connecting the Southern Croatia to the north of Apulia. Our previous study based on macroscopic and chemical analysis of a selection of 151 samples of chert from mining districts and geological outcrops throughout Gargano Promontory (Northern Apulia) provided a reference dataset to compare with new data obtained on flint tools and debitage from archaeological excavated contexts at Scaloria, Masseria Candelaro, Monte Aquilone (Tavoliere area), and Balsignano and Madonna delle Grazie (Murge area). New colorimetric (CIELAB) and chemical (portable XRF) data on 80 samples showed that most of the flints from the Tavoliere settlements share the same chemical/colorimetric features, together with few samples from Murge ones. Further, the flint from Madonna delle Grazie and Balsignano show different compositional groupings not compatible with those of the mining districts of Gargano. The relatively small size of most of these artefacts points to the use of secondary flint sources, associated with the continental deposits from the Tavoliere area, not yet characterised
Modelling of thermo-mechanical behaviour of pre-industrial ceramics: functional analysis via an experimental and a numerical approach
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Investigating the evolution of fractures in clay–based ceramics during repeated freeze-thawing cycles using micro X-ray computed tomography and image analysis
Full text linkAcknowledgements Ignazio Allegretta was supported by a research grant on the project PON R&I – Progetto AIM1809249 – attivitá 1, linea 1. Data Availability The raw/processed data required to reproduce these findings cannot be shared at this time as they include more than 4TB of raw micro-tomographic data. However, for those researchers interested in analysing this dataset, tomographic data will be made available upon request by contacting the Dr. Carlo Porfido (e-mail: [email protected]). The FracPaQ toolbox, used for image analysis, is freely available to download from the following addresses: http://fracpaq.com/index.html.Peer reviewe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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