Detailed litho,-biostratigraphic analyses are carried out on the two lower Eocene stratigraphic sections at Kharga-Baris oases namely; Gabal El Aguz and Darb Gaga. These lower Eocene sediments are represented by two rock units: Esna Formation (at the base) and Thebes Formation (at the top). Only the upper two members of the Esna Formation (El Mahmiya and Abu Had) are included in the present work. Based on the nannofossil marker species two zones are recognized covering the Early Eocene interval; NP10 and NP11. Quantitative analyses of the calcareous nannofossil species lead to recognize two distinct assemblages, which indicating a cool and an eutrophic to mesotrophic marine environmental conditions. At G. El Aguz, the depositional setting are marked by deep marine environmental conditions characterize El Mahmiya and the lower part of Abu Had members, while the nannofossil contents of the upper part of Abu Had Member reflect shallow marine setting. In contrast, the whole succession of Darb Gaga section is deposited under shallow marine environmental conditions. These changes in the depositional setting could be interpreted as a result of sea level fluctuations due to the tectonic events during the Early Eocene interval with greater magnitude at Darb Gaga section.

Benthic foraminiferal fauna are analyzed quantitatively and qualitatively at three stratigraphic sections in Eastern Desert of Egypt(Serai, Duwi, and Um El Huetat). These sections embrace the Paleocene–Eocene Thermal Maximum (PETM) interval which is represented by the occurrence of five distinctive beds. These beds constitute the Dababiya Quarry Member at the lower part of Esna Formation. The occurrence of them indicates an expanded and relatively continuous record across the P/E boundary. The organic-rich clay layer (bed no. 1 of the Dababiya Quarry Member) marks the start of the PETM event. This bed is characterized by the extinction of all benthic foraminiferal fauna except for the occurrence of rare agglutinated foraminiferal species. The presence of these species indicates an oceanic anoxic event at the sea floor. High concentration of phosphatic contents including fish remains occurred in the middle part of the PETM (bed nos. 2 and 3 of the Dababiya Quarry Member) with the continuous absence of benthic foraminiferal fauna except for few specimens at the top of bed 3. Bed nos. 4 and 5 of the Dababiya Quarry Member represent the upper part of the PETM and the initial stage of sea floor recovery. Low diversity and abundance of benthic foraminiferal taxa occurred within these beds, represented by Valvulineria scrobiculata, Lenticulina midwayensis, Loxostomoides appliane, and Siphogenerinoides eleganta. This phenomenon continues upward during the post-PETM event.The Paleocene velasco-type benthic foraminifera Angulogavelinella avnimelechi and Coryphostoma midwayensis species are extinct within the advent of the PETM event. The benthic foraminiferal assemblages at the studied sections are dominated by midway-type fauna with little representative of velasco-type fauna. The velasco-type species are represented with high abundance at Serai section and with low densities at Um El Huetat section, while at Duwi section, they rarely occurred. This suggests outer neritic-upper bathyal (150–400 m) setting at Serai section and mostly middle-outer neritic (50–150 m) setting at Um El Huetat and Duwi sections.

Benthic foraminiferal fauna are analyzed quantitatively and qualitatively at three stratigraphic sections in Eastern Desert of Egypt(Serai, Duwi, and Um El Huetat). These sections embrace the Paleocene–Eocene Thermal Maximum (PETM) interval which is represented by the occurrence of five distinctive beds. These beds constitute the Dababiya Quarry Member at the lower part of Esna Formation. The occurrence of them indicates an expanded and relatively continuous record across the P/E boundary. The organic-rich clay layer (bed no. 1 of the Dababiya Quarry Member) marks the start of the PETM event. This bed is characterized by the extinction of all benthic foraminiferal fauna except for the occurrence of rare agglutinated foraminiferal species. The presence of these species indicates an oceanic anoxic event at the sea floor. High concentration of phosphatic contents including fish remains occurred in the middle part of the PETM (bed nos. 2 and 3 of the Dababiya Quarry Member) with the continuous absence of benthic foraminiferal fauna except for few specimens at the top of bed 3. Bed nos. 4 and 5 of the Dababiya Quarry Member represent the upper part of the PETM and the initial stage of sea floor recovery. Low diversity and abundance of benthic foraminiferal taxa occurred within these beds, represented by Valvulineria scrobiculata, Lenticulina midwayensis, Loxostomoides appliane, and Siphogenerinoides eleganta. This phenomenon continues upward during the post-PETM event.The Paleocene velasco-type benthic foraminifera Angulogavelinella avnimelechi and Coryphostoma midwayensis species are extinct within the advent of the PETM event. The benthic foraminiferal assemblages at the studied sections are dominated by midway-type fauna with little representative of velasco-type fauna. The velasco-type species are represented with high abundance at Serai section and with low densities at Um El Huetat section, while at Duwi section, they rarely occurred. This suggests outer neritic-upper bathyal (150–400 m) setting at Serai section and mostly middle-outer neritic (50–150 m) setting at Um El Huetat and Duwi sections.

Benthic foraminiferal fauna are analyzed quantitatively and qualitatively at three stratigraphic sections in Eastern Desert of Egypt(Serai, Duwi, and Um El Huetat). These sections embrace the Paleocene–Eocene Thermal Maximum (PETM) interval which is represented by the occurrence of five distinctive beds. These beds constitute the Dababiya Quarry Member at the lower part of Esna Formation. The occurrence of them indicates an expanded and relatively continuous record across the P/E boundary. The organic-rich clay layer (bed no. 1 of the Dababiya Quarry Member) marks the start of the PETM event. This bed is characterized by the extinction of all benthic foraminiferal fauna except for the occurrence of rare agglutinated foraminiferal species. The presence of these species indicates an oceanic anoxic event at the sea floor. High concentration of phosphatic contents including fish remains occurred in the middle part of the PETM (bed nos. 2 and 3 of the Dababiya Quarry Member) with the continuous absence of benthic foraminiferal fauna except for few specimens at the top of bed 3. Bed nos. 4 and 5 of the Dababiya Quarry Member represent the upper part of the PETM and the initial stage of sea floor recovery. Low diversity and abundance of benthic foraminiferal taxa occurred within these beds, represented by Valvulineria scrobiculata, Lenticulina midwayensis, Loxostomoides appliane, and Siphogenerinoides eleganta. This phenomenon continues upward during the post-PETM event.The Paleocene velasco-type benthic foraminifera Angulogavelinella avnimelechi and Coryphostoma midwayensis species are extinct within the advent of the PETM event. The benthic foraminiferal assemblages at the studied sections are dominated by midway-type fauna with little representative of velasco-type fauna. The velasco-type species are represented with high abundance at Serai section and with low densities at Um El Huetat section, while at Duwi section, they rarely occurred. This suggests outer neritic-upper bathyal (150–400 m) setting at Serai section and mostly middle-outer neritic (50–150 m) setting at Um El Huetat and Duwi sections.

Integrated high resolution calcareous planktonic nannofossil and foraminiferal biostratigraphic studies are carried out on the Paleocene/Eocene (P/E) boundary at Gebel El Aguz and Gaga on the eastern plateau of the Kharga-Baris oases, Western Desert, Egypt. The five beds of the Dababiya Quarry Member of the Esna Formation are represented partially on the study sections. At G. El Aguz beds nos. 1–4 are missing, whereas at Gaga bed no.1 is absent which indicates the occurrence of a hiatus with different magnitude. This hiatus is documented by the occurrence of irregular surface with pebbles at G. El Aguz and the occurrence of glauconitic layers at Gaga section. Biostratigraphically, the P/E boundary is defined at the NP9a/NP9b nannofossil zonal boundary which is equivalent to the Morozovella velascoensis (P5)/Acarinina sibaiyaensis (E1) at Gaga section and A. soldadoensis/Globanomalina pseudomenardii (P4c)/A.sibaiyaensis (E1) planktonic foraminiferal zonal boundaries at G. El Aguz with interzonal hiatus. This indicates that the sedimentary basin during the P-E interval at the study area was unstable and affected by a tectonic event may be due to the echo of the Syrian Arc Orogeny.

The increasing anthropogenic activities (e.g., constructing touristic resorts) have led to notable changes in the Yemeni Red Sea coastal regions. In this context, recent sediments have been investigated to infer possible natural and man-induced processes on these coastal areas. The target area lies between longitudes 43130–43300E and latitudes 13150–13550N. It extends about 90 km along the coastline as a part of the Tihama plain. Geomorphologically, it forms a longcurved stretch with pronounced headlands, embayments and bays. Generally, it is covered by recent sediments (wadi, lagoon, beach and spit deposits along with sabkha, coastal dunes and mangrove). Textural studies reveal that most of the studied sediments are mainly poorly to moderately sorted and are composed mainly of sandy fractions with few gravel and mud, mostly bimodal with minor unimodal patterns. The igneous (granites) as well as basic (basalt, andesite and andesitic pyroclastics) and acidic (dacite and rhyolite) volcanic rocks of Tertiary age, which are exposed to the east of the study area, are believed to be the source of pyroxenes, amphiboles, epidotes, biotite, sphene, zircon, tourmaline and rutile, in a decreasing order of abundance. Moreover, smectite, kaolinite, chlorite, illite and palygorskite are the predominant clay minerals, mainly of detrital origin. The total carbonate content fluctuates from 37.41% (lagoon sediments) to 53.74% (sabkha sediments). The high amount of sea grasses, which covers the tidal flat zone and relates to the fine-grained sediments, accounts for the high organic matter content. The mineralogy of the source rocks has controlled the general distribution of major elements (Fe, Mg, Na, K and Mn) in the beach sediments. In such sediments, the concentrations of the heavy metals (Cu, Zn, Cd, Ni, Pb and Co) may reflect the sediment pollution using different approaches. The enrichment factors (EFs) of the trace metals for most samples reveal values that are greater than 1, referring to three groupings, which are: moderate to moderately severe (Zn, Cu and Mn), minor to moderate (Pb and Co) and zero to minor (Cd and Ni) enrichment. The EFs for Pb, Cd, Ni and Co metals (5) may be attributed to the crustal materials and/or natural weathering processes. But, those for Zn, Cu and Mn ([5), especially in Al-Khowkhah–Abu-Zahr, Moushij– Zahari–Ruays, Yokhtol and Mokha localities, are possible of anthropogenic contributions.

The increasing anthropogenic activities (e.g., constructing touristic resorts) have led to notable changes in the Yemeni Red Sea coastal regions. In this context, recent sediments have been investigated to infer possible natural and man-induced processes on these coastal areas. The target area lies between longitudes 43130–43300E and latitudes 13150–13550N. It extends about 90 km along the coastline as a part of the Tihama plain. Geomorphologically, it forms a longcurved stretch with pronounced headlands, embayments and bays. Generally, it is covered by recent sediments (wadi, lagoon, beach and spit deposits along with sabkha, coastal dunes and mangrove). Textural studies reveal that most of the studied sediments are mainly poorly to moderately sorted and are composed mainly of sandy fractions with few gravel and mud, mostly bimodal with minor unimodal patterns. The igneous (granites) as well as basic (basalt, andesite and andesitic pyroclastics) and acidic (dacite and rhyolite) volcanic rocks of Tertiary age, which are exposed to the east of the study area, are believed to be the source of pyroxenes, amphiboles, epidotes, biotite, sphene, zircon, tourmaline and rutile, in a decreasing order of abundance. Moreover, smectite, kaolinite, chlorite, illite and palygorskite are the predominant clay minerals, mainly of detrital origin. The total carbonate content fluctuates from 37.41% (lagoon sediments) to 53.74% (sabkha sediments). The high amount of sea grasses, which covers the tidal flat zone and relates to the fine-grained sediments, accounts for the high organic matter content. The mineralogy of the source rocks has controlled the general distribution of major elements (Fe, Mg, Na, K and Mn) in the beach sediments. In such sediments, the concentrations of the heavy metals (Cu, Zn, Cd, Ni, Pb and Co) may reflect the sediment pollution using different approaches. The enrichment factors (EFs) of the trace metals for most samples reveal values that are greater than 1, referring to three groupings, which are: moderate to moderately severe (Zn, Cu and Mn), minor to moderate (Pb and Co) and zero to minor (Cd and Ni) enrichment. The EFs for Pb, Cd, Ni and Co metals (5) may be attributed to the crustal materials and/or natural weathering processes. But, those for Zn, Cu and Mn ([5), especially in Al-Khowkhah–Abu-Zahr, Moushij– Zahari–Ruays, Yokhtol and Mokha localities, are possible of anthropogenic contributions.

The Upper Cretaceous-Lower Paleogene succession at Gabal Qreiya area that covers six rock units, Quseir, Duwi, Dakhla, Tarawan, Esna, and Thebes formations, is reviewed through a high-resolution sequence stratigraphic analysis. Six third-order depositional sequences and their associated surfaces and systems tracts are recognized based on stratigraphic, sedimentological, and high-resolution foraminiferal studies. The pre-Campanian sequence, comprising the Quseir Formation, was accumulated in inner neritic paleodepths, on marginal to shallow subtidal shelf. The Lower Campanian sequence that covers the Duwi Formation was accumulated in oscillating settings between inner to middle neritic paleodepths, on a shallow subtidal shelf. The Upper Campanian-Maastrichtian sequence that covers the lower part of the Dakhla Formation was accumulated in outer neritic-upper bathyal to middle neritic paleodepths, on a deep subtidal shelf to a shallow subtidal shelf. The Danian sequence that covers the middle part of the Dakhla Formation was accumulated in oscillating conditions between upper bathyal and middle neritic paleodepths, on a deep subtidal and a shallow subtidal shelf. The Selandian-Thanetian sequence that comprises the upper part of the Dakhla, Tarawan, and the lower part of the Esna formations was accumulated in fluctuating conditions from upper bathyal to middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. The Ypresian sequence that includes the main parts of Esna and Thebes formations was accumulated in fluctuating settings among middle bathyal and middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. Most of the sequence boundaries coincide with the global sea-level curve whereas some of them suggest a local tectonic event.

The Upper Cretaceous-Lower Paleogene succession at Gabal Qreiya area that covers six rock units, Quseir, Duwi, Dakhla, Tarawan, Esna, and Thebes formations, is reviewed through a high-resolution sequence stratigraphic analysis. Six third-order depositional sequences and their associated surfaces and systems tracts are recognized based on stratigraphic, sedimentological, and high-resolution foraminiferal studies. The pre-Campanian sequence, comprising the Quseir Formation, was accumulated in inner neritic paleodepths, on marginal to shallow subtidal shelf. The Lower Campanian sequence that covers the Duwi Formation was accumulated in oscillating settings between inner to middle neritic paleodepths, on a shallow subtidal shelf. The Upper Campanian-Maastrichtian sequence that covers the lower part of the Dakhla Formation was accumulated in outer neritic-upper bathyal to middle neritic paleodepths, on a deep subtidal shelf to a shallow subtidal shelf. The Danian sequence that covers the middle part of the Dakhla Formation was accumulated in oscillating conditions between upper bathyal and middle neritic paleodepths, on a deep subtidal and a shallow subtidal shelf. The Selandian-Thanetian sequence that comprises the upper part of the Dakhla, Tarawan, and the lower part of the Esna formations was accumulated in fluctuating conditions from upper bathyal to middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. The Ypresian sequence that includes the main parts of Esna and Thebes formations was accumulated in fluctuating settings among middle bathyal and middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. Most of the sequence boundaries coincide with the global sea-level curve whereas some of them suggest a local tectonic event.

The Upper Cretaceous-Lower Paleogene succession at Gabal Qreiya area that covers six rock units, Quseir, Duwi, Dakhla, Tarawan, Esna, and Thebes formations, is reviewed through a high-resolution sequence stratigraphic analysis. Six third-order depositional sequences and their associated surfaces and systems tracts are recognized based on stratigraphic, sedimentological, and high-resolution foraminiferal studies. The pre-Campanian sequence, comprising the Quseir Formation, was accumulated in inner neritic paleodepths, on marginal to shallow subtidal shelf. The Lower Campanian sequence that covers the Duwi Formation was accumulated in oscillating settings between inner to middle neritic paleodepths, on a shallow subtidal shelf. The Upper Campanian-Maastrichtian sequence that covers the lower part of the Dakhla Formation was accumulated in outer neritic-upper bathyal to middle neritic paleodepths, on a deep subtidal shelf to a shallow subtidal shelf. The Danian sequence that covers the middle part of the Dakhla Formation was accumulated in oscillating conditions between upper bathyal and middle neritic paleodepths, on a deep subtidal and a shallow subtidal shelf. The Selandian-Thanetian sequence that comprises the upper part of the Dakhla, Tarawan, and the lower part of the Esna formations was accumulated in fluctuating conditions from upper bathyal to middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. The Ypresian sequence that includes the main parts of Esna and Thebes formations was accumulated in fluctuating settings among middle bathyal and middle neritic paleodepths, on a deep subtidal to a shallow subtidal shelf. Most of the sequence boundaries coincide with the global sea-level curve whereas some of them suggest a local tectonic event.