Chlorine as a Discriminant Element to Establish the Provenance of Central Mediterranean Obsidians

Chlorine is a minor element present in obsidians in quantities greater than in average igneous rocks. The chlorine concentration in obsidians is generally low, of the order of tenths of wt %, but it exhibits an appreciable differentiation among geological sources. Despite these characteristics, chlorine has rarely been taken into consideration as a possible indicator of obsidian provenance and it does not appear in the chemical analytical tables accompanying the geochemical characterisation of obsidian samples. In this work, after an overview of chlorine geochemistry and cycle, we present thirty-one new electron microprobe (EPMA) analyses, including Cl, of geologic obsidians sampled from the four sources of the Central Mediterranean, exploited in prehistoric times (Monte Arci, Palmarola, Lipari and Pantelleria). The results are compared with 175 new EPMA analyses, including Cl, of archaeological obsidians already characterised in previous work and of known provenance. As such it was possible to ascertain that each source has a characteristic chlorine concentration, showing the utility of its use in the studies of obsidian provenance. Furthermore, given that the solubility of chlorine in silicate melts is correlated to its alkali content, in particular sodium, we assessed the efficacy of simple binary graphs Cl vs Na2O to better constrain the provenance of the obsidian samples

The argonautica orphica version for the voyage of the argonauts: A geo-analysis

This study traces and analyzes the itinerary followed by Argo and her crew, according to the unknown author of Argonautica Orphica: The voyage of the Argonauts from Iolcos to Colchis and their return following a different path, from Phasis River through central Europe to the Atlantic Ocean and then through the Mediterranean Sea. Conclusions are drawn about whether such a voyage could be possible in the remote antiquity and the “problematic” points of the description are pointed out. © 2017 MAA Open Access. Printed in Greece. All rights reserved

THE ARGONAUTICA ORPHICA VERSION FOR THE VOYAGE OF THE ARGONAUTS: A GEO-ANALYSIS

This study traces and analyzes the itinerary followed by Argo and her crew, according to the unknown author of Argonautica Orphica: The voyage of the Argonauts from Iolcos to Colchis and their return following a different path, from Phasis River through central Europe to the Atlantic Ocean and then through the Mediterranean Sea. Conclusions are drawn about whether such a voyage could be possible in the remote antiquity and the “problematic” points of the description are pointed out