ROCK MAGNETIC AND PALAEOMAGNETIC ANALYSES ON LITHIC FRAGMENTS FROM THE ARCHAEOLOGICAL SITE OF AKROTIRI, SANTORINI

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Published: Jul 27, 2016
DOI: https://doi.org/10.12681/bgsg.11831
Keywords:
Rock magnetism Pumice fall Lithic clast Akrotiri archaeological site Santorini
E. Tema
Dipartimento di Scienze della Terra, Università degli Studi di Torino
Abstract

Rock magnetic and palaeomagnetic analyses on lithic clasts collected from the pumice fall deposited inside the archaeological site of Akrotiri have been applied in order to estimate the deposition temperature of the first volcanic products of the Minoan eruption. A total of 50 lithic clasts have been collected from four different locations inside the excavation of Akrotiri. All samples have been stepwise thermally demagnetized and the obtained results have been interpreted through principal component analysis. The equilibrium temperature obtained after the deposition of the pumice fall varies from sample to sample but generally shows temperatures around 240-280oC. These temperatures are in good agreement with those estimated from lithic clasts from the Megalochori Quarry while they are higher compared with those from ceramic fragments from Akrotiri. The new temperature data presented here show that the pumice fall was still relatively hot when deposited inside the archaeological site and even if it interacted with the buildings, often causing the collapse of roofs, it still remained hot with mean temperature around 260oC.

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  • Geophysics and Seismology
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