Evdokia Tema: The Earth's magnetic field in Italy during the Neolithic period
Channel: Institute for Rock Magnetism
Date: 2021-06-02

12th Institute for Rock Magnetism Conference 

Lightning Talk

Title: The Earth's magnetic field in Italy during the Neolithic period: New data from the Campi Diomedei archaeological site (Foggia, Italy)

Authors: Evdokia Tema (1,2) & Italo Maria Muntoni (3)

Institutions:
(1) Dipartimento di Scienze della Terra, Università degli Studi di Torino, via Valperga 35, 10125, Torino, Italy
(2) CIMaN-ALP Alpine Laboratory of Palaeomagnetism, via G.U. Luigi Massa 6, 12016, Peveragno, Italy
(3) Soprintendenza Archeologia, Belle Arti e Paesaggio per le Province di Barletta - Andria - Trani e Foggia, via Alberto Alvarez Valentini 8, 71121, Foggia, Italy

Abstract:
Archaeomagnetic data from ancient baked clays is a precious source of information about the past variations of the Earth's magnetic field. However, as we go back in time, retrieving suitable, well dated and still in situ baked clay archaeological structures becomes a difficult and challenging task. We present here the results of an archaeomagnetic study carried out on three hearths (UUSS 148, 158 and 201) excavated in 2018-2019 at the Early Neolithic village of the Ex Ippodromo (actually Campi Diomedei), situated at Foggia (Southern Italy). The three discovered firing structures are dated at 5800-5500 BCE based on archaeological information and radiocarbon dating. Magnetic mineralogy experiments show the dominance of a low coercivity mineral, most probably magnetite and/or Ti-magnetite, completely demagnetized at 580 oC. Stepwise thermal demagnetization procedures accompanied by bulk magnetic mineralogy monitoring were used to investigate the thermal stability of the samples while systematic alternative field demagnetization was carried out to determine the archaeomagnetic direction registered by the hearths during their last firing. The new directions, which are very well defined, are in very good agreement with the directions previously obtained from the Neolithic ovens of Portonovo (Marche) and the combustion structures of Balsignano (Bari) as well as with other contemporaneous data from Europe. Independent archaeomagnetic dating of the three hearths is also obtained using the SHA.DIF.14k geomagnetic field model. The obtained results are in good agreement with the radiocarbon dates. The new directional records aim to enrich our knowledge of the geomagnetic field during the Neolithic period that is poorly covered by data, and show that archaeomagnetic dating can provide accurate results even for prehistoric periods.