1,721,341 research outputs found
The transition from alkaline to tholeiitic magmatism: a case study from NE Sardinia (Italy)
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Ophiolitic olistoliths in Middle Miocene turbidites (Cilento Group) at Mount Centaurino (Southern Apennines; Italy).
No full textTrace element and Sr-Nd-Pb isotope geochemistry of Plio-Quaternary volcanic rocks of Sardinia (Italy)
No full textRaw materials for ancient ceramic productions from Campania region: provenance studies by means of Sr-Nd isotopes
No full textWhen archaeometric studies on archaeological ceramics are performed, one of the most important questions
asked by archaeologists is the provenance of pottery. This is usually performed by comparing mineropetrographic
and chemical composition of ceramics with that of local raw materials (clays, temper), production
indicators and appropriate reference groups. Nevertheless, the commonly-used analytical techniques (e.g. OM,
SEM-EDS, XRF, ICP-MS) may not always be helpful for the determination of provenance. Indeed, processing
of raw materials, such as tempering or levigation, can significantly modify their original chemical composition,
sometimes leading to an ineffective identification of raw material resources. For this reason, a pioneering
analytical approach has been recently applied by measuring the Sr and Nd isotopic signature.
Isotope analysis has largely used in archaeological sciences to date objects and identify their provenance,
making it also a useful tool for the determination of provenance of ceramic vessels (De Bonis et al., 2018 and
references therein). For this study, 87Sr/86Sr and 143Nd/144Nd isotope ratios were measured on archaeological
pottery from Campania and raw materials (clays and volcanic temper) exploited in antiquity for producing
ceramics. The analyses were focused on samples from both the Bay of Naples and Southern Campania. The
isotope signatures allowed us to better discriminate among different productions and find a strong relationship
between the archaeological pottery and the geological sources of raw materials.
In order to validate the method, Sr-Nd isotope ratios were also measured for the first time on experimental
ceramic materials that replicate archaeological pottery (De Bonis et al., 2018). It was interesting to note that
synthetic mixtures used for the ceramic replicas plot exactly on the theoretical mixing curve between the
clay and volcanic temper end-members. This suggests that the artificial manipulation of raw materials (firing,
levigation, tempering) induces no significant variations to the Sr-Nd isotope fingerprint, which strictly depends
on the geochemical affinity of the raw materials. Thus, isotopic analysis can be considered as an effective
and robust method that could complement the common multi-analytical approach in order to more precisely
constrain potential geological sources for ceramic materials and pottery provenance.
De Bonis, A., Arienzo I., D’Antonio, M., Franciosi, L., Germinario, C., Grifa, C., Guarino, V., Langella, A. & Morra, V.
(2018): Sr-Nd isotopic fingerprint as a tool for ceramic provenance: application on raw materials, ceramic replicas and
ancient pottery. J. Archaeol. Sci., 94, 51-59
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
Plagioclase textures, mineralogy and petrology of Tertiary orogenic volcanic rocks from Sindia (central Sardinia)
No full textErratum: Evidence of crystallization in residual, Cl-F-rich, agpaitic, trachyphonolitic magmas and primitive Mg-rich basalt-trachyphonolite interaction in the lava domes of the Phlegrean Fields (Italy) (Geological Magazine (2011) DOI: 10.1017/S0016756811000902)
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