113,163 research outputs found
Gianfranco Morra tra filosofia e sociologia
No full textRicostruzione dell'itinerario intellettuale e scientifico di Gianfranco Morra. Analisi delle sue opere e aggiornamento di un predecente studio. Valutazioni critiche
Raw 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
The transition from alkaline to tholeiitic magmatism: a case study from NE Sardinia (Italy)
No full textOphiolitic olistoliths in middle-lower Miocene turbidites (Cilento group) at Mount Centaurino (Southern Apennines; Italy).
No full textThe transition from alkaline to tholeiitic magmas: a case study from the Orosei-Dorgali Pliocene volcanic district (NE Sardinia, Italy)
No full textDuring the Pliocene, simultaneously with the opening of the Tyrrhenian Sea, mafic magmas were erupted in NE Sardinia (Orosei-Dorgali area). These range from mildly alkaline with sodic affinity (about 80% of exposure) to tholeiitic (about 20%). The tholeiitic rocks (basaltic andesite) are slightly more evolved than the alkaline ones and show geochemical features (e.g., Mg# 20). Similar incompatible element ratios for both alkaline and tholeiitic rocks suggest different degrees of melting of a single mantle source. Mathematical modeling indicates similar to 4-6% and similar to 10-15% partial melting for alkaline and tholeiitic lavas, respectively. Trace element abundances of the Orosei-Dorgali volcanic rocks are typical of Plio-Pleistocene volcanic rocks of Sardinia but differ strongly from other Cenozoic anorogenic volcanic rocks of Europe. Similarly, Sr (Sr-87/Sr-86=0.70442-0.70455), Nd (Nd-143/Nd-144=0.512465-0.512558) and Ph (Pb-206/Pb-204=17.74-17.86; Pb-207/Pb-204=15.53-15.60; Pb-208/Pb-204=37.89-38.02) isotopic ratios are very unusual when compared with other Cenozoic European volcanic rocks. Trace element abundances and isotopic composition of the Orosei-Dorgali volcanic rocks suggest a lithospheric mantle origin. (C) 2002 Elsevier Science B.V. All rights reserved
- …
