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

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Publiée : Jul 27, 2016
DOI : https://doi.org/10.12681/bgsg.11831
E. Tema
Dipartimento di Scienze della Terra, Università degli Studi di Torino
Résumé

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.

Article Details
  • Rubrique
  • Geophysics and Seismology
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Références
Aramaki, S. and Akimoto, S., 1957. Temperature estimation of pyroclastic deposits by natural
remanent magnetism, Am. J. Sci., 255, 619-627.
Bardot, L., 2000. Emplacement temperature determinations of proximal pyroclastic deposits on
Santorini, Greece, and their implications, Bull. Volcanol., 61, 450-467.
Bond, A. and Sparks, R.S., 1976. The Minoan eruption of Santorini, Greece, Journal of the
Geological Society of London, 132, 1-16.
Cioni, R., Gurioli, L., Sbrana, A. and Vougioukalakis, G., 2000. Precursory phenomena and
destructive events related to the Late Bronze Age Minoan (Thera, Greece) and AD 79
(Vesuvius, Italy) Plinian eruptions; inferences from the stratigraphy in the archaeological
areas. In: The Archaeology of Geological Catastrophes, McGuire, W.G., Griffiths, D.R.,
Hancock, P.L. and Stewart, I.S., eds., Geological Society Special Publication, London, 171,
-141.
Cioni, R., Gurioli, L., Lanza, R. and Zanella, E., 2004. Temperatures of A.D. 79 pyroclastic density
currents deposits (Vesuvius, Italy), J. Geophys. Res., 109, B02207, doi:
1029/2002JB002251.
Cogné, J.R., 2003. PaleoMac: a Macintosh application for treating palaeomagnetic data and making
plate reconstructions, Geochem. Geophys. Geosyst., 4(1), 1007, doi:
1029/2001GC000227.
Doumas, Ch., 1974. The Minoan eruption of the Santorini volcano, Antiquity, XLVIII, 110-115.
Downey, W.S. and Tarling, D.H., 1984. Archaeomagnetic Dating of Santorini Volcanic Eruptions
and Fired Destruction Levels of Late Minoan Civilization, Nature, 309(5968), 519-523.
Druitt, T.H., Mellors, R.A., Pyle, D.M. and Sparks, R.S.J., 1989. Explosive volcanism on Santorini,
Greece. Geol. Mag., 126, 95-126.
Heiken, G. and McCoy, F., 1984. Caldera development during the Minoan eruption, Thera,
Cyclades, Greece, J. Geophys. Res., 89, B 10, 8441-8462.
McClelland, E. and Druitt, D.H., 1989. Palaeomagnetic estimates of emplacement temperatures of
pyroclastic deposits on Santorini, Greece, Bull. Volcanol., 51, 16-27, doi:
1007/BF01086758.
McClelland, E., Kondopoulou, D., Westphal, M. and Sophos, Ph., 1996. Palaeomagnetic estimation
of emplacement temperatures of plinian airfalls on Santorini, Greece. In: Casale, R., Fytikas,
M., Sigvaldasson, G. and Vougioukalakis, G., eds., The European laboratory volcanoes,
Proceedings of the 2nd workshop, 2-4 May 1996, Santorini, Greece.
McCoy, F. and Heiken, G., 2000. The Late Bronze Age explosive eruption of Thera (Santorini),
Greece: Regional and local effect, Geological Society of America, Special paper, 345, 43-70.
Paterson, G.A., Roberts, A.P., Mac Niocaill, C., Muxworthy, A.R., Gurioli, L., Viramonte, J.G. and
Navarro, C., 2010. Paleomagnetic determination of emplacement temperatures of pyroclastic
deposits: an underutilised tool, Bull Volcanol., 72, 309-330, doi: 10.1007/s00445-009-0324-4.
Porreca, M., Mattei, M., Mac Niocaill, C., Giordano, G., McClelland, E. and Funiciello, R., 2008.
Paleomagnetic evidence for low-temperature emplacement of the phreatomagmatic Peperino
Albano ignimbrite (Colli Albani volcano, Central Italy), Bull. Volcanol., 70, 877-893, doi:
1007/s00445-007-0176-8.
Sparks, R.S.J. and Wilson, C.J.N., 1990. The Minoan deposits: a review of their characteristics and
interpretation. In: Hardy, D., Keller, J., Galanopoulos, V.P., Flemming, N.C. and Druitt,
T.H., eds., Thera and theAegean World III, vol. 2. The Thera Foundation, London, 89-99.
Sulpizio, R., Zanella, E. and Macías, J.L., 2008. Deposition temperature of some PDC deposits from
the 1982 eruption of El Chichón volcano (Chiapas, Mexico) inferred from rock magnetic
data, J. Volcanol. Geotherm. Res., 175, 494-500, doi: 10.1016/j.jvolgeores.2008.02.024.
Tema, E., Kondopoulou, D. and Pavlides, S., 2013a. Palaeotemperature estimation of the pyroclastic
deposit covering the pre-Minoan palaeosol at Megalochori Quarry, Santorini (Greece):
Evidence from magnetic measurements, Stud. Geophys. Geod., 57, 627-646, doi:
1007/s11200-013-0601-8.
Tema, E., Pavlides, S. and Kondopoulou, D., 2013b. Late Bronze age pottery as indicator of the
deposition temperatures of the Minoan pyroclastic products, Santorini, Greece, Bulletin of
the Geological Society of Greece, XLVII, Proceedings of the 13th International Congress,
Chania, Sept. 2013.
Tema, E., Zanella, E., Pavón-Carrasco, F.J., Kondopoulou, D. and Pavlides, S., 2015.
Palaeomagnetic analysis on pottery as indicator of the pyroclastic flow deposits temperature:
new data and statistical interpretation from the Minoan eruption of Santorini, Greece,
Geophys. J. Int., 203, 33-47, doi: 10.1093/gii/ggv267.
Zanella, E., Gurioli, L., Pareschi, M.T. and Lanza, R., 2007. Influences of urban fabric on pyroclastic
density currents at Pompeii (Italy): 2. Temperature of the deposits and hazard implications,
J. Geophys. Res., 112, B05214, doi: 10.1029/2006JB004775.
Zanella, E., Sulpizio, R., Gurioli, L. and Lanza, R., 2015. Temperatures of the pyroclastic density
currents deposits emplaced in the last 22 kyr at Somma-Vesuvius (Italy). Geological Society,
London, Special Publication: “The Use of Palaeomagnetism and Rock Magnetism to
Understand Volcanic Processes”, 396, doi:10.1144/SP396.5.
Zijderveld, J.D.A., 1967. A.C. demagnetization of rocks: Analysis of results. In: Methods in
Palaeomagnetism, Collinson, D.W., Creer, K.M. and Runcorn, S.K., eds., Elsevier,
Amsterdam.
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