Rekonstruktion von Paläosäkularvariationen des Erdmagnetfeldes an holozänen marinen Sedimenten aus der Region des Makran Akkretionskeils

Abstract

Annually laminated marine sediments from the Makran accretionary wedge off Pakistan were cored during cruises SO 90 (1993) and SO 130 (1998) with the RV SONNE. Sediments from the earlier cruise have been dated by varve counting and other methods back to 5000 y.b.p. From the same site core 315KA (24°49´N/65°54´E; SO130) has been retrieved, correlated to the dated core and continuously sampled at 2.5 cm intervals. Detailed rock magnetic analysis suggests that the main carriers of the magnetization are predominantly single domain/pseudo single domain magnetite and shows that the sediment preserved magnetic signals with an excellent quality. For the first time a high-resolution and well dated secular variation record of the paleomagnetic field for the past 3600 years (Holocene) from marine sediment was obtained for the Northeastern Arabian Sea region.The determined paleointensity of the Earth magnetic field during the past 3600 years corresponds in most parts to the results of investigations of Egypt (Aitken et al., 1984; Hussain, 1983, 1987; Odah et al., 1995; Odah, 1999), Central Asia (Nachasova et al., 2000), Bulgary (Kovacheva, 1997), Italy (Frank, 1999) and Pennsylvania (King et al., 1983). Though the directions reflect reliable data it appears that they can t be clearly correlated with records of other investigations.