Sergiou, SpyrosGeraga, MariaRohling, EelcoRodriguez Sanz, LauraPrandekou, A.Noti, A.Paraschos, FrancescaSakellariou, DimitrisBailey, Geoff2025-05-072025-05-070377-8398https://hdl.handle.net/1885/733749961The southern Red Sea is affected by intense interactions between monsoon and sea level changes in a semi-closed environment. Still, the impacts on the wide shelves remain poorly documented. We investigate the seafloor environmental conditions on the southern Red Sea shelf over the last 30 ka through sedimentological (visual inspection, granulometry, bulk density), geochemical (organic carbon, calcium carbonate and nitrogen content) and micropaleontological (benthic foraminifera) observations in a previously dated sediment core (FA09) from the Farasan Islands Archipelago. Glacial sediments exhibit high density and low carbonate contents, whereas post-glacial sediments reflect increased biogenic productivity. Seafloor oxygenation was limited in most of the glacial interval, along with hypersaline conditions. During the maximum sea level lowstand, an enhanced presence of eutrophic-indicator benthic assemblages likely reflects efficient organic matter preservation induced by weak water ventilation. Our proxies combined with a previous surface-water productivity reconstruction reveals a coupling between organic matter flux to the seafloor and surface productivity levels in the southern Red Sea shelf, particularly pronounced during periods of enhanced summer monsoon. This pattern is often accompanied by a decrease in seafloor oxygenation. In contrast, well oxygenated and more oligotrophic seafloor conditions are recorded around the time of Heinrich Stadial 2, when previous work indicates a reduction in summer monsoon intensity and surface productivity levels. A drastic decrease of benthic foraminifera along with increased organic carbon contents in late glacial and late Holocene reflect oxygen-depleted seafloor conditions that we attribute to expansion of an intensified southern Red Sea oxygen minimum zone (OMZ).The present study arises from the “DISPERSE: Dynamic Landscapes, Coastal Environments and Human Dispersals” research project, funded by the European Research Council under the Ideas Programme of the 7th Framework Programme as Advanced Grant 269586. We thank the Saudi Commission for Tourism and National Heritage (SCTH) and the Department of General Survey of the Ministry of Defense for fieldwork permissions. We are also grateful to the crew of the R/V AEGAEO for successfully undertaking the coring survey. Finally, S. Sergiou thanks the General Secretariat for Research and Technology (GSRT) and the Hellenic Foundation for Research and Innovation (HFRI) for scholarship funding during his research work. This is DISPERSE contribution no. 65.application/pdfen-AU©2022 The authorsRed SeaSea level changesSeafloor conditionsMonsoonBenthic foraminiferaPaleoceanography202210.1016/j.marmicro.2022.1021812023-12-10