Significance of the sedimentary Al:Ti ratio as an indicator for variations in the circulation patterns of the equatorial North Atlantic

Abstract

This paper presents results of geochemical investigations conducted on three gravity cores recovered along an E-W transect (3°-5°N) in the equatorial Atlantic. Considering the high terrigenous content of the sediments (approximately 12-74 wt%), Al and Ti concentrations are predominantly associated with the input of lithogenous phases. The terrigenous fraction of western equatorial Atlantic sediments is more influenced by material derived from the Amazon River than by deposition of African dust particles. As a possible route of transport, the North Equatorial Countercurrent is considered. Fluctuations in Al/Ti records generally reflect changes in the low-latitude insolation cycle (19-23 kyr) ..