The planktonic foraminiferal morphogroups and planktonic quantitative analysis as well as the lithological variations across the Pre-Albian to Maastrichtian sediments of Gebel Arif El Naga section (Northeastern Sinai, Egypt) are studied in detail in order to detect the prevailing paleoecological conditions (paleotemperature and paleodepth) along these sediments.
At the studied area of Gebel Arif El Naga there is a clear warming trend from the latest Cenomanian of the Halal Formation (extinction level of Rotalipora cushmani) to the earliest Turonian (Abu Qada Formation) is observed due to the high abundance of Whitenella and Hedbergella at this transition. Unfortunately, the Wata Formation (Middle-Upper Turonian) is barren of planktonic foraminifera.
A gradual cooling started at the base of Globotruncana elevata Zone (early-middle Campanian) of the lower part of the Markha Member and continued till Globotruncana tricarinata Zone (late Campanian-early Maastrichtian) of the upper part of the Markha Member. This trend corresponds to the onset of a global cooling that began at about 73 Ma (Late Campanian) and ended the Cretaceous greenhouse climate mode.
At Gebel Arif El Naga section, a gradual warming started at the base of Pseudogumbelina palpebra Zone (Late Maastrichtian) and continued till Plummerita hantkeninoides Zone (latest Maastrichtian) due to the high abundance of Plummerita hantkeninoides and P. reicheli, which have been flourishing in warm waters. So this warming near the end of the Maastrichtian is a global event as shown by many authors.
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