Recurrent Geomagnetic Excursions: A Review for the Brunhes Normal Polarity Chron

Abstract

Until now, a large number of records of geomagnetic excursions have been reported both for volcanic rocks and sedimentary sequences. By straightening up the, extensive excursion records, 23 geomagnetic excursions were identified in total for the Brunhes. Eighteen out of 23 excursions are considered to be reliably determined and dated. Above all, Mono Lake 3234 ka , Las-champ 3941 ka , Blake 115122 ka and Iceland Basin 180190 ka are well-documented worldwide excursions. Others include Hilina Pali 1823 ka , Norwegian-Greenland Sea 6080 ka , Albuquerque 140160 ka , Jamaica/Pringle Falls 210220 ka , Fram Strait 255265 ka , Kolbeinsey Ridge 280290 ka , Calabrian Ridge 1 310320 ka , Agulhas Ridge 330340 ka , Weinen 400420 ka , West Eifel 500510 ka , Calabrian Ridge 2 535545 ka , Emperor/Big Lost 550570 ka , Calabrian Ridge 3 580605 ka , and Delta 665690 ka. Most of these excursions can be correlated with minima in relative paleointensity records of Sint-800 and ODP Site 983, suggesting that excursions occur due to dominance of a non-dipole field at minima of the main dipole field intensity.