Following a decade of studies in search of appropriate criteria
for selecting/defining and characterizing/correlating an optimum
location/level for a GSSP, the Working Group on the
Paleocene/Eocene boundary selected the 1.65 m level at the
base of Section DBH in the Dababiya Quarry, on the east bank
of the Nile River, about 35 km south of Luxor, Egypt (text-figs.
1-3). This level is correlative with the onset of a Carbon Isotope
Excursion (CIE) that was denoted as the primary criterion for
recognition and correlation of the Eocene GSSP. This (lithologic)
definition was formalized (Aubry et al. 2007) following
ratification by the IUGS at the 33rd IGC (Florence, August
2004). The basal Bed 1, the oldest bed of the Eocene Epoch, is a
dark gray clay, and one of five characteristic beds (named the
“Dababiya Quarry Beds”, Ouda and Aubry, eds., 2003,
text-figs. 4a and b, this paper) that outcrop through extensive areas
of the Middle East. These five beds (~3.5 m-thick in the
Dababiya GSSP section) that occur in an otherwise monotonous
lithology of shales (~120 m in the quarry) are indicative of a
major disruption that affected the Earth system at the time of
their deposition. Elsewhere, this disruption has left its mark in
the sedimentary record, in most instances with abrupt changes
in lithology.