NEW AGE-DETERMINATIONS FOR THE EOCENE-OLIGOCENE BOUNDARY SEDIMENTS IN THE FAYUM DEPRESSION, NORTHERN EGYPT

The Fayum Depression of northern Egypt contains the richest collection of fossil vertebrates known from the Afro-Arabian Paleogene. This fauna has been collected for over a century, and yet the sediments containing the fossil localities have remained undated. Paleomagnetic sampling was carried out through the fossil-bearing Jebel Qatrani Formation and the underlying Dir Abu Lifa Member of the Qasr el Sagha Foundation to determine a correlation between the paleomagnetic reversal stratigraphy and the Geomagnetic Reversal Time Scale (GRTS). A new date of 23.64 +/- 0.035 Ma was determined for the overlying Widan cl Faras Basalt by the laser incremental-heating Ar-40/Ar-40 dating method. The results of this study indicate that the majority of the vertebrate fossil localities occur in Chrons C13-Cl5r late Eocene to early Oligocene in age. These age determinations provide a minimum date for the origin of higher primates.