Planktonic foraminiferal biostratigraphy of the Paleocene/Eocene boundary interval in the Dababiya Quarry Corehole, Dababiya, Upper Nile Valley, Egypt

摘要

We report here on the planktonic foraminiferal faunas of the Paleocene-Eocene boundary interval between 21.15 m (Tarawan Chalk/Esna Shale 1 boundary; basal Zone P4c) and the basal part of the Mahmiya Member of Esna Shale Unit 3 (～5-6 m; Zone E2; Lower Eocene) in the Dababiya Quarry Corehole (DQC). The sequential lower/initial late Paleocene appearance of several morozovellid and acarininid taxa in the ～10 minterval from the top of the Tarawan Chalk (21.15 m) to the base of the lithologically distinct Dababiya Quarry Member (11.82 m), the presence of the characteristic PETM excursion planktonic fauna (Acarinina sibaiyaensis, Ac. africana and Morozovella allisonensis) within the DBQ Beds (11.82 m to 9.5 m), the "Eocene flood"of planktonic faunal elements and the LO/initial appearance of Pseudohastigerna wilcoxensis in Bed 5 of the DBQ Beds mirrors our earlier observations in the nearby Dababiya Quarry outcrops and makes precise correlation between the two sections possible.