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We present the first Italian reference secular variation curves for both direction and intensity that cover the last 3000 years. Strict selection criteria were applied to guarantee the collection of the most reliable data within a 1000 km radius of Viterbo, including archaeomagnetic records from archaeological material and volcanic rocks. The new curves are calculated using Bayesian statistics and they depict interesting geomagnetic field features, such as high‐intensity periods. These are the first curves for Italy, including both directional and intensity data, and they can be used as reference curves for archaeomagnetic dating, not only in Italy but also in nearby countries. [ABSTRACT FROM AUTHOR]

Abstract: An archaeomagnetic study was carried out as part of a rescue operation on a lime kiln discovered during the exploitation of a gravel quarry at Bazzano, near Bologna (northern Italy). Based on very poor archaeological information the kiln is dated around 3rd–4th century AD but no other structures have been found in the area to support this age. A hierarchical sampling process has been followed; twelve independently oriented bricks were collected from the circular wall of the baking room from which 35 cylindrical specimens were cut and measured. Demagnetization procedures reveal a single-component, stable remanent magnetization. The dispersion of the mean direction is low, even though some deviations in the remanence direction as a function of the position of the samples in the kiln wall are observed. The archaeomagnetic age of the kiln has been obtained using recent advances on data elaboration involving Bayesian statistics and the preliminary secular variation (SV) curve of Italy. For comparison, the kiln has been also dated using the French SV curve. The ages obtained are in good agreement and suggest that the last firing of the kiln could have occurred as late as at the end of 6th century AD. [Copyright &y& Elsevier]

Published Italian archaeomagnetic data are combined with new data from the Genève and Torino laboratories. A total of 74 directional data is presented with age estimates falling between 1300 BC to 1600 AD, including results from volcanic deposits of unquestionable age. The data set has been analysed using the Bayesian stochastic approach for curve building to produce a preliminary Italian secular variation (SV) curve. Comparison with the French SV curve shows a general agreement but some significant differences are also observed. The new Italian SV curve can be used for archaeomagnetic dating of Italian artefacts, even though caution must be paid for the period 9th–12th century AD and times older than 8th century BC, when only few data are available and error envelopes are large. [ABSTRACT FROM AUTHOR]

Abstract: Archaeodirectional results from kilns and other baked structures in southern Italy are presented. They are generally compatible with the much larger data sets from France and Bulgaria. In particular, a summary of all the results associated with the well-known eruption of Vesuvius that destroyed Pompeii (n =9, D =355°, I =58°, α 95 =1.5°) provides a reliable archaeomagnetic anchor point supporting the French and Bulgarian master curves. It is extremely well-constrained in time and it comprises independent studies carried out in four different countries. Furthermore, it is derived from a diverse set of features agreement amongst which argues strongly against significant perturbations due to magnetic refraction, structural disturbance, or depositional shallowing. In terms of geomagnetic secular variation, we interpret the western European archaeomagnetic data summarized here in terms of an open loop caused by westward drift, followed by an inclination low spanning the first few centuries CE representing the signal of a static flux pulse that reaches a maximum magnetic moment of a few percent of the earth''s main central dipole. [Copyright &y& Elsevier]

The inclination (I), declination (D) and total intensity (F) of the geomagnetic field were measured on Mount Etna in 1989–1991 at a dozen sites previously sampled for archeomagnetic studies. The purpose of the work was to determine the variations of these parameters at 30 cm above ground level, and how the distortion from the main field can affect the archeomagnetic record of volcanic rocks. Ten measurements were usually performed at each site with a three-component flux-gate magnetometer, whose estimated precision is ±0.2° on direction and ±50 nT on intensity. This was considered sufficient on volcanic areas with highly magnetized rocks and where the geomagnetic gradient may be in excess of 1000 nT/m. Results averaged for each site generally show small variations in intensity (±3% of the total field) and direction (±1.5°). The averaged values of the 12 sites (I=52.6°, D=0.3°, F=44010 nT) are very close to those measured in sedimentary terrain away from the volcano (I=52.9°, D=0.35°, F=44110 nT), themselves consistent with the interpolated IGRF in eastern Sicily. The largest deviations of the geomagnetic direction have been observed on four sites, three of them located on the South flank between 1900 and 700 m elevation. It is suggested that these anomalies are mainly related to dyke swarms which are common within the South Rift Zone of Mount Etna. Our findings show that reliable archeomagnetic results can be obtained from volcanic rocks, provided that lavas of the same eruption are sampled on several sites distributed over the largest possible area. [Copyright &y& Elsevier]