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This study is part of a multidisciplinary project dealing with the investigation of geoarchaeological sites on the Egyptian Plateau. With the aim of reconstructing the palaeoecological background, providing age assessment which put the various results in an age frame that is of special interest. Here, results of one particular section have been selected because of a discrepancy in age determination based on different approaches. Radiocarbon ages were inconsistent with the age range provided by the archaeological context in this area. The underestimation observed is inferred to be caused by poor C-14-sample quality. An attempt to overcome this problem was the determination of the depositional ages of the non-organic sediments by using optically stimulated luminescence (OSL). Equivalent doses of four sediment samples were estimated from OSL measurements carried out on sand-sized quartz grains using the single-aliquot regenerative-dose (SAR) protocol. Dose rates were calculated from neutron activation analysis results. From the OSL ages obtained, we conclude that the sediment sequence exposing an alternation of lacustrine and eolian layers was deposited in a short period of time during the mid-Holocene (mean of OSL ages similar to 7.8 ka). Compared to the C-14 ages, the luminescence ages fit better into the archaeological context confirmed by surface dating. (C) 2003 Elsevier Science Ltd. All rights reserved.