![]() Eccentricity forcing (405 and 100 kyr) and precession frequencies are found in the entire studied interval. ![]() This suggests continent-wide aridity or larger climate variability during that interval. Between 3.2 and 2.9 Ma, ODP Site 959 Ti/Ca ratios exhibit three maxima corresponding to eccentricity maxima similarly to other dust records of northern Africa. From the increased values and variability of Ti/Al and Ti/Ca ratios, we suggest that after 3.5 Ma dust started to reach the study site probably as a result of the southward shift of the Intertropical Convergence Zone during winter. A long-term decrease of river supply is documented after 5.4 Ma until the end of the Pliocene. During the interval corresponding to the earlier stages of the Messinian Salinity Crisis, our proxy records indicate enhanced run-off from the West African continent and major supply of fine material at ODP Site 959, suggesting a stronger monsoon and increased precipitation during eccentricity minima. We discuss sedimentation patterns at ODP Site 959 associated with the environmental changes from the late Miocene until the early Pleistocene. Based on this new stratigraphy, we studied the variations of Ti/Al, Ti/Ca and Al/Si ratios, proxies for aeolian versus fluvial supply, as dust indicator and fine versus coarse grain size, respectively. Iron intensity data have been used to build a 91-m composite depth record that has been astronomically tuned allowing the development of a detailed age model from 6.2 to 1.8 Ma. ![]() ![]() In this study, new high-resolution XRF data from ODP Site 959 (3☃7′N, 2☄4′W) have been used to investigate the relationship between palaeoenvironmental changes in West Africa and sedimentation in the tropical East Atlantic Ocean. Palaeorecords from tropical environments are important to explore the linkages between precipitation, atmospheric circulation and orbital forcing. ![]()
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