Integrated biostratigraphy, stage boundaries and Paleoclimatology of the Upper Cretaceous–Lower Eocene successions in Kharga and Dakhala Oases, Western Desert, Egypt H. Khalil ⇑ , S. Al Sawy Geology Department, Faculty of Science, Tanta University, Egypt article info Article history: Received 17 November 2013 Received in revised form 4 April 2014 Accepted 5 April 2014 Available online 2 May 2014 Keywords: Cretaceous Paleogene Calcareous nannofossils Planktonic foraminifera Biostratigraphy Stage boundaries abstract The Upper Cretaceous–Lower Eocene succession in the studied sections is divided into four rock units that arranged from base to top: the Dakhla, Tarawan, Esna and the Thebes formations. Detailed study of the foraminifera and calcareous nannofossils has led to the recognition of 58 and 82 species, respectively. Based on planktonic foraminifera and calcareous nannofossils 8 planktonic foraminiferal biozones (CF4, P2, P3, P4, E1, E2, E3 and E4) have been recognized as well as 8 calcareous nannofossil biozones (CC25b, NP3, NP4, NP5, NP6, NP7/8, NP9, and NP10). At Gabal Teir/Tarawan section, Kharga Oasis, the Paleocene can be divided into three stages; Danian, Selandian and Thanetian. The Danian/Selandian boundary is placed at P3a/P3b zonal boundary (LO of Igo- rina albeari) which corresponds to the level of LO of Lithoptychius ulii, Fasciculithus pileatus, Fasciculithus involutus and Lithoptychius janii (upper part of Zone NP4). The Selandian/Thanetian boundary, on the other hand, can be traced within the foraminiferal Zone P4 (Globanomalina pseudomenardii Zone) and between the nannofossil zones NP6 and NP7/8 (LO of Discoaster mohleri). At Gabal Ghanima section, the Paleocene/Eocene boundary is located within the lower part of the Esna Formation. It can be traced at the base of planktonic foraminiferal Zone E1 (LOs of Acarinina africana, A sibaiyaensis and Morozovella allinsoensis), and at the NP9a/NP9b subzonal boundary (LO of Rhomboaster spp). However, the lower Eocene succession seems to be condensed and punctuated by minor hiatus (absence of Subzone NP10a). The dominance of cool water nannofossil species in the late Maastrichtian and early Danian interval suggests a gradual decrease in the surface water paleotemperature. However, a slight warming condition prevailed around the Danian/Selandian transition as evidenced by the warm water nannofossil species. At the P/E boundary interval, the high abundance of warm-water taxa (e.g. Discoaster, Sphenolithus, Rhomboaster, Tribrachiatus and Pontosphaera species) indicates a warm-water paleotemperatures. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction The Upper Cretaceous–Lower Paleogene successions of the Western Desert have attracted several studies with special empha- sis on the general geology, stratigraphy and paleontology (e.g., Abdel-Kireem and Samir, 1995; Tantawy et al., 2000; EL-Azabi and Farouk, 2010). The surface geology of the Kharga Oasis has been the subject of numerous studies including those by Bassiouni et al. (1991), Faris (1993), Tantawy (1998), Faris et al. (1999), Ouda et al. (2004), Obaidalla et al. (2008), Tantawy (2006) and El-Azabi and Farouk (2010). Also, several studies have been published on the stratigraphy, of the Maastrichtian–Paleo- cene rocks exposed in the Dakhla–Farafra stretch of the Western Desert (e.g. Faris et al., 1999; Tantawy et al., 2001; Obaidalla et al., 2008; EL-Azabi and Farouk, 2010). The aim of the present study is to integrate the data obtained from planktonic foraminifera and calcareous nannofossils to subdivide the Late Cretaceous–Early Paleogene into biostrati- graphic units, as well as their biostratigraphic correlation, delineate and discuss some of the Paleocene and Early Eocene stage boundaries, shed light on the Paleocene hiatuses in the studied area and to predict the paleoecological conditions that prevailed during the deposition of the Cretaceous/Paleocene and Paleocene/lower Eocene succession in the area under consideration. http://dx.doi.org/10.1016/j.jafrearsci.2014.04.010 1464-343X/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +20 1201095731. E-mail address: hamzakhalil2002@yahoo.com (H. Khalil). Journal of African Earth Sciences 96 (2014) 220–242 Contents lists available at ScienceDirect Journal of African Earth Sciences journal homepage: www.elsevier.com/locate/jafrearsci