Palaeomagnetic results from Minoan ash deposits in (RV Vema) cores V10-50 and V10-58, south Aegean Sea

Part of : Mediterranean archaeology & archaeometry : international journal ; Vol.11, No.2, 2011, pages 151-168

Issue:
Pages:
151-168
Section Title:
Articles
Author:
Abstract:
Palaeomagnetic and anisotropy measurements were carried out on Minoan ash deposits ob-tained from the deep-sea cores, (V10-50 and V10-58), South Aegean Sea. Three distinct layers have been reported within the ash deposit in core (V10-50). Based primarily on grain-size differences, a link to three separate eruptive phases of Santorini has been suggested. Magnetic results were una-ble to resolve any differences between these layers which suggests that the eruption may have been a ‘single event’. Some magnetic parameters indicate that the final ignimbrite phase of the eruption of Santorini is most likely to have been responsible for the bulk of the deep-sea ash deposits, alt-hough a contribution from the first phase (phreatomagmatic and/or Plinian air-fall) cannot be ex-cluded. Anisotropy of magnetic susceptibility measurements indicate a primary sedimentary fabric and quiet depositional conditions for V10-50 ash sediment. A more disturbed petrofabric is ob-served for V10-58 suggesting, bottom current activity and/or slumping. The mean palaeomagnetic inclination calculated from appropriate V10-50 results is:- 60.2° ± 4.3° (corrected for anisotropy and geographical location differences of sites). This is statistically identical to values obtained for burnt mud brick from destruction sites in eastern Crete but different to the mean palaeomagnetic inclina-tion obtained for central Cretan sites. A comparison with the secular variation (inclination) data for the Balkan region and for Greece, suggests that the eruption/s of Santorini occurred in the period between ~1540 and 1500 BC.
Subject:
Subject (LC):
Keywords:
Deep-sea cores, ash deposits, magnetic remanence, inclination, secular variation, ani-sotropy, Santorini, dating
Notes:
The author thanks the Lamont-Doherty Earth Observatory (in particular Floyd McCoy) for sup-plying and allowing magnetic measurements on the Vema Minoan ash samples. Thanks also to the anonymous referees and to Phua Eng Siong, Nur Farah Tuah and Mdm Lim Yeely (University Bru-nei Darussalam) for technical assistance. The project was originally funded by the former Science and Engineering Research Council (UK)., Corresponding author: billdowney49@yahoo.com