The Paleocene-Eocene GSSP at Dababiya, Egypt - Revisited

Abstract

We investigated the Paleocene-Eocene boundary GSSP (Dababiya quarry) near Luxor, Egypt, in two nearby (25m and 50m) sequences based on high-resolution biostratigraphy, lithostratigrapy, mineralogy and geochemistry. Results confirm the many positive aspects of the Dababiya GSSP but also show potentially serious limiting factors: (1) the GSSP is located in the deepest part of a ∼200 m wide submarine channel, which limits its use as global type section. (2) Some lithologic units identified at the GSSP are absent or thin out and disappear within the channel and beyond. (3) The P-E boundary is placed at the base of a clay layer above an erosion surface with variable erosion of latest Paleocene and earliest Eocene sediments. (4) The current definition of the P-E boundary as marked by the abrupt onset of the carbon isotope excursion at the base of a clay layer is not supported at the GSSP because 50m to the left the excursion begins gradually 60cm below the P-E boundary and reaches minimum values in the boundary clay. With awareness of these limiting factors and recognition of the gradual onset of the PETM excursion the GSSP can contribute significantly to a more complete understanding of this global warm event.