Foraminiferal biostratigraphy, paleoenvironmental interpretation, and sequence stratigraphy of the latest Maastrichtian–Thanetian succession in the Southern Galala Plateau, Eastern Desert, Egypt

Abstract

We present an integrated study of two stratigraphic sections from the Southern Galala Plateau that combines foraminiferal biostratigraphy with quantitative paleoenvironmental proxies and sequence stratigraphic analysis across the latest Maastrichtian–Thanetian interval. High-resolution planktic zonations (Maastrichtian CF2–CF1; Paleocene P1c–P4c) reveal variable temporal hiatuses at the Cretaceous/Paleogene (K/Pg) boundary, with an abrupt planktic foraminifera extinction, a low benthic foraminiferal extinction (∼9%), and drops in TFN, HOFS%, and paleodepth, followed by increased EBFOI, reflecting improved bottom water oxygenation in the Danian. The Latest Danian Event (LDE) is recorded only in South Wadi El-Maheer, characterized by brown nodular calcareous shale, high HOFS%, low EBFOI, a paleodepth drawdown, and the invasion of the Neoeponides duwi assemblage. The Danian/Selandian (D/S) boundary exhibits a pronounced sea-level fall, mirroring the global signal. Its placement varies between both sections due to differences in hiatus magnitude, which is greater in Wadi Ragela, as indicated by an abrupt planktic foraminiferal assemblage shift and the reduced thickness of P3a and P3b. The sequence stratigraphic analysis revealed seven third-order depositional sequences in Wadi Ragela and five in South Wadi El-Maheer. The proposed sequence stratigraphic framework confirms that the study area was influenced by eustatic changes and regional tectonic activities.