Palaeomagnetism of Holocene and Late Pleistocene sediments from Lago di Mezzano and Lago Grande di Monticchio (Italy): initial results

Palaeomagnetic records of the geomagnetic secular variation reaching back to 31 and 102 kyr cal. BP, respectively, were obtained from two sediment cores from Lago di Mezzano (central Italy) and two cores from Lago Grande di Monticchio (southern Italy). Intra-lake correlation was based on continuous high-resolution susceptibility measurements and discrete dry density samples. Characteristic remanent magnetization (ChRM) of all 4800 samples was determined by analysis of the results of progressive alternating field (AF)-demagnetization. Intra-lake comparison of the resulting ChRM-directions confirms that the inclination and declination records reflect the palaeosecular variation of the local geomagnetic field. Composite curves of geomagnetic palaeosecular variations (PSV) were created for each lake in order to compare the reconstructed PSV records with those from Lac du Bouchet (Massif Central, France) and Lac de Joux (Switzerland). The good agreement in the general patterns of the inclination and declination records of all lakes mentioned above, confirms the reconstructed PSV records of the Italian lakes investigated. (C) 1999 Elsevier Science Ltd. All rights reserved.