New magnetic mineralogy and archaeointensity results from greek kilns and baked clays

Abstract

Seven archaeological sites in Northern Greece and a pottery assemblage from IthakiIsland (Ionian Sea) have provided material from kilns and a collection of baked clays. The whole dataset consists of 69 samples and covers a period of almost 4000 years. Although the majority of the samples was oriented, only few directions could be obtained, mostly due to small sample size and fragility. Detailed rock magnetic experiments identified magnetite/titano-magnetite and substituted magnetite as the main magnetic minerals. Variable amounts of haematite were detected in some cases. In three out of eight sites, multi-domain grains prevail, whereas single-, pseudo-single domain or mixtures are detected in the remaining five. The classical Thellier-Thellier palaeointensity method was applied to 94 specimens. Following stringent acceptance criteria, 66 results from the 8 sites were considered successful and retained. These new results show a convergence with regional and global compilations and improve the knowledge of the past geomagnetic field behaviour in Greece.

An Archaeometric and Archaeological Approach to Hellenistic-Early Roman Ceramic Workshops in Greece: Contribution to Dating

“…The archaeomagnetic directions were generally well grouped, with well-defined inclinations and declinations. Several successful laboratory experiments provided reliable archaeointensity results (De Marco et al 2008a, b;Spatharas et al 2011). In cases of failure during the relevant experiment, the classical rock-magnetic protocols for sample preselection proved to be insufficient for reducing this failure, as suggested by Morales et al (2011).…”

“…Apart from the already published results (Spatharas 2005;De Marco 2008a, b;Aidona et al 2010;Spatharas et al 2011;Tema et al 2012), additional thermomagnetic analysis and Triaxe experiments (Le Goff and Gallet 2004) were carried out to complement the existing data set.…”

“…A detailed description of each site and the sampling strategy involved is given in Spatharas (2005), De Marco (2007), De Marco et al (2008a), and Spatharas et al (2011). A brief description is given below together with basic information regarding the geological background-an important factor likely to affect our study since kilns were constructed from locally available material.…”

Improving our knowledge of rapid geomagnetic field intensity changes observed in Europe between 200 and 1400 AD

“…As for western Europe only data derived from Thellier derived experiments and including pTRM checks have been retained. A total of 42 data from Bulgaria (N ¼33, Kovacheva et al, 2009a), Greece (N ¼6, De Marco et al, 2008;Spatharas et al, 2000Spatharas et al, , 2011Tema et al, 2012) and Italy (N ¼3; Leonhardt et al, 2006;Tema et al, 2010) have been selected and relocated to the latitude of Sofia through the VADM (Fig. 7b).…”

Archeointensities in Greece during the Neolithic period: New insights into material selection and secular variation curve

“…Numerous studies have provided high quality data for both the direction and intensity of the geomagnetic field in Europe e.g., compilations of (Genevey and Gallet, 2002, 2003. In particular, Greece owns a substantial number of suitable archeological materials and volcanic fields, so that numerous data are available from such artefacts (Aitken et al, 1984(Aitken et al, , 1989DeMarco, 2007Spatharas et al, 2011;Aidona and Kondopoulou, 2012;Tema et al, 2012) or historical lava flows (Spassov et al, 2010). The most recent Greek secular variation curves (SVCs) are available for the last 8 millennia for the intensity and the last 6 millennia for the direction .…”