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A combined geomorphological, radiocarbon dating, archaeological and historical approach permits a refining of the age of the coastal dune systems related to estuaries in the Gulf of Cádiz. Three dune systems are distinguished in this paper. The oldest one, D1, which accumulated under prevailing WSW winds during the first millennium bc, overlays both the occupational horizons of Late Neolithic-Early Copper Age (fourth millennium bc) and the‘lithic workshop levels' (fourth to second millennia bc). The middle dune system, D2, containing both Roman and medieval remains, accumulated between the thirteenth or fourteenth centuries and the seventeenth century ad. The youngest D3 system is associated with the time of building of watchtowers in the seventeenth century ad but extends to the present; it is related to SW prevailing winds. We explain the absence of aeolian deposits prior to 2700 cal. BP as the result of trapping of a large part of the sediment supply in the estuaries, which starved the neighbouring beaches and aeolian settings. Aeolian accumulation reached significant values when sedimentation in the coastal zone changed from being mainly aggradational in the estuaries (6500–2700 cal. BP) to mainly progradational in spit barriers and related dunes (post 2700 cal. BP). The present analysis of aeolian systems suggests a non-direct correlation, at least in some cases, between coastal progradation of spit barriers and aridity.

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During the late Pleistocene to mid-Holocene, the Medjerda river system in Mediterranean Tunisia shows events of increased flooding and aggradation of relatively coarse overbank deposits. Geomorphic activity in river systems within this region correlate with aridification of the climate, but not with temperature. The late-Pleistocene to mid-Holocene synthetic profile of the Ghardimaou floodplain (mid-Medjerda river) indicates fluvial activity from 12.4 to 11.8, 6.6 to 6.0 and after 4.8 ka cal. BP. External correlations imply global and regional causes of the late-Pleistocene to mid-Holocene climatic development such as North Atlantic deep-water formation, fluctuations in Saharan humidity and impacts of local Mediterranean weather phenomena. Palaeomagnetic records offer additional opportunities to interpret fluvial activity in river systems, especially for detecting chronological hiatuses in apparently homogeneous sediment sequences.

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