The Paleocene-Eocene GSSP at Dababiya, Egypt – Revisited

We investigated the Paleocene-Eocene boundaryGSSP (Dababiya quarry) near Luxor, Egypt, in twonearby (25m and 50m) sequences based on high-resolution biostratigraphy, lithostratigrapy, mineralogyand geochemistry. Results confirm the many positiveaspects of the Dababiya GSSP but also show potentiallyserious limiting factors: (1) the GSSP is located in thedeepest part of a ~200 m wide submarine channel, whichlimits its use as global type section. (2) Some lithologicunits identified at the GSSP are absent or thin out anddisappear within the channel and beyond. (3) The P-Eboundary is placed at the base of a clay layer above anerosion surface with variable erosion of latest Paleoceneand earliest Eocene sediments. (4) The current definitionof the P-E boundary as marked by the abrupt onset ofthe carbon isotope excursion at the base of a clay layeris not supported at the GSSP because 50m to the leftthe excursion begins gradually 60cm below the P-Eboundary and reaches minimum values in the boundaryclay. With awareness of these limiting factors andrecognition of the gradual onset of the PETM excursionthe GSSP can contribute significantly to a more completeunderstanding of this global warm event.  PDF