Chronology of Pleistocene sedimentary cycles in the western Mediterranean

Abstract

This study focuses on the sedimentological and stratigraphic description and chronology of Pleistocene coastal deposits on the Pityusic Islands (Balearic Islands, Spain). These deposits show evidence of interference between processes characteristic of alluvial, marine, and aeolian environments. Optically stimulated luminescence dating of aeolian levels indicates that deposition took place from the Lower to Upper Pleistocene. The sedimentological and chronological analysis of these deposits allows reconstruction of coastal Pleistocene environmental history from MIS 22 to MIS 2. The results show that changes in the average wind direction over time, modulated by the interaction with coastal relief orientation, were the main controls on the Lower to Upper Pleistocene coastal landscape evolution on the Pityusic Islands. The main episodes of aeolian activity identified in the Western Mediterranean, can be linked to periods of low sea level. The study's findings the presence of two dominant environments, coastal aeolian and alluvial, each characterized by distinct geological processes. Interestingly, these processes have led to the formation of deposits that exhibit a combination of characteristics from both environments. Moreover, these deposits retain elements inherited from each environment in terms of sedimentary supply, precipitation, runoff or aeolian transport. These results corroborated by OSL dating provide a useful indicator of the geomorphological processes and changes that occurred during the Pleistocene, unraveling the environmental evolution, and contributing to the growing knowledge on western Mediterranean aeolian or aeolian-alluvial interacting environments during the last 1000 ka.