PALEOMAGNETIC SECULAR VARIATION OF LATE PLEISTOCENE AND HOLOCENE SEDIMENT, GULF OF SALERNO, WESTERN MEDITERRANEAN SEA

Sediment in a 6-m gravity core from the Gulf of Salerno in the western Mediterranean Sea records long-term change (secular variation) of Earth's magnetic field during much of the last approximately 40,000 years. The age of the sediment is based on tephrochronology and correlation to the relative intensity in the NAPIS-75 (Laj et al., 2000) and SAPIS (Stoner et al., 2002). The core (GS1202, 40º08.34'N, 14º43.57'E, 243 m) has a hiatus between about 14,000 and 24,000 yrs B.P. caused by slumping of shelf margin sediments (Trincardi et al., 2003). Where GS1202 overlaps in time with a second core (GS1201, 40º28.92'N, 14º42.24'E, 300 m), also from the Gulf of Salerno and that terminates at about 25,000 yrs B.P. (Iorio et al., 2006), there is good agreement of paleomagnetic directions and normalized intensity. Both cores confirm very well the paleomagnetic record for the last 8,000 years in a third core from the Gulf of Salerno (Iorio et al., 2004). An objective of our investigation is a search for the Laschamp (LE) and Mono Lake (MLE) excursions, believed to be either a single excursion (Kent et al., 2002) or two that differ in age by 6,000 to 8,000 years (Benson et al., 2003). Unstable field directions in GS1202 occur during relative field minimums at about 34,000 and 40,000 yrs B.P.; these portions of the record that may represent the LE and MLE are being further investigated using the archive half of the core.