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To extract V5+ ions from the ferruginous siltstone in the Abu Zeneima region of Southwestern Sinai, Egypt, a chelating polyimine ligand (PVAm-Ben) was synthesized via a condensation reaction involving polyvinyl amine and a-hydroxy ketone (Benzoin). The structure of PVAm-Ben underwent comprehensive characterization employing various techniques, namely; FT-IR, 1HNMR, 13C-NMR, and GC/MS analyses. Experimental factors controlling such as pH, time, initial concentration, dosage, temperature, and stripping, were systematically optimized to enhance measurement accuracy. Under conditions of 25°C, 0.015 mol/L, and 30 minutes, PVAm-Ben/C2H4Cl2 exhibited remarkable retention capacity at pH 3. Linear regression analysis results suggested the release of a mole of H+ during the extraction process. The stability constant (log ß = 2.1882) of the PVAm-Ben/V5+ complex was determined, yielding a value of 154.24. The stoichiometry mechanism between PVAm-Ben and V5+ ions displayed a linear correlation (slope: 0.9922), signifying 1 mole of PVAm-Ben reacting with 1 mole of vanadium. The pseudosecond-order kinetic model indicated an exothermic, spontaneous, and advantageous extraction process at low temperatures. Efficient stripping of PVAm-Ben/C2H4Cl2 loaded with vanadium was achieved using 0.05 M NaOH with a 99% efficiency rate. Ultimately, enhanced variables were employed to yield a V2O5 concentrate with a vanadium content of 55% and a purity level of 98.21%. [ABSTRACT FROM AUTHOR]

To extract vanadium (V) ions from the ferruginous siltstone at Abu Zeneima in Southwestern Sinai, Egypt, a synthesized chelating N-phenyl acetyl-N-naphthyl hydroxyl amine (PANHA), was used. Complete characterization was carried out successfully to elucidate the structure using several techniques such as FT-IR,1H-NMR, 13C-NMR, GC-MS and TGA analysis performances. Improved experimental measurements, such as pH, shaking time, initial concentration of V(V), PANHA dosage, temp., and stripping agents, have been achieved with the solvent extraction technique. At 25 ℃ and 0.015 mole per liter through 30 minutes, PANHA/CHCl3 has an extreme retention potential of 50 mg per gram at 25 ℃ at pH 1.5 at 1:1 aqueous to organic phase ratio. The linear regression analysis, consisting of a log D track versus pH, shows a straight line with a slope of 0.859, indicates that a mole of H+ was released during the extraction. The stability constant (β), of PANHA-V(V) complex was calculated from the intersection (log β=1.7958), and it was found to equal 63.1. The stoichiometry mechanism among a chelating ligand of PANHA and V(V) indicates a roughly linear correlation with slope of 0.882 which explains that one mole of PANHA chelating ligand can react with one mole of V (V). According to the kinetic and thermodynamic interpretations, the pseudo-second order kinetic model predicted the kinetics of vanadium (V) extraction, the thermodynamic factors ΔS, ΔH, and ΔG were also measured. As the temperature rises, ∆G values rise from -10.45 kJ/mol at 198 K to -2.2 kJ/mol at 353 K. Vanadium may be stripped from the loaded PANHA/CHCl3, by 0.5M NaOH with a 99% efficiency rate. To obtain a vanadium concentrate (NH4VO3, AMV) with a vanadium content of 42.6 percent and pureness of 98 percent, the enhanced variables were finally put to use. [ABSTRACT FROM AUTHOR]

Dinosaur footprints occur in the Upper Cretaceous strata known as the Nubian Sandstone Formation in the south Eastern Desert, Egypt. The Nubian Sandstone unit is subdivided into three informal members: A lower member is marked by reddish‐brown, trough cross‐bedded, coarse‐ to medium‐grained sandstone interbedded with thin beds of varicolored mudstone, reflecting deposition in a braided fluvial system, a middle member is characterized by reddish‐white to yellow, planar cross‐bedded, medium‐grained sandstone with ferruginous siltstone intercalations, interpreted as meandering fluvial deposits, and an upper member consists of repeated coarsening‐upward cycles of rippled siltstone to fine‐ to medium‐grained sandstone and planar cross‐bedded, yellowish‐white sandstone, containing many vertebrate footprints and invertebrate trace fossils, reflecting deposition in a coastal to deltaic environment. Sixteen dinosaur footprints are recorded at the base of the upper member of the Nubian Sandstone, on inclined surfaces of rippled, fine‐grained sandstones. Twelve are overlapping each other and belong to distinct individuals of dinosaurs, the other four are distributed on a younger bedding surface. Twelve footprints are from more than one sauropod dinosaur, while three of the isolated footprints belong to a theropod dinosaur. The footprints described are semiplantigrade and digitigrade. This discovery is the second record of tetrapod footprints in Egypt and the first record of tetrapod footprints in the Eastern Desert. [ABSTRACT FROM AUTHOR]

The Coniacian–Santonian Matulla Formation is one of the important reservoirs in the July oilfield, Gulf of Suez Basin. However, this formation is characterized by uncertainty due to the complexity of reservoir architecture, various lithologies, lateral facies variations and heterogeneous reservoir quality. These reservoir challenges, in turn, affect the effectiveness of further exploitation of this reservoir along the Gulf of Suez Basin. In this work, we conduct an integrated study using multidisciplinary datasets and techniques to determine the precise structural, petrophysical, and facies characteristics of the Matulla Formation and predict their complex geometry in 3D space. To complete this study, 30 2D seismic sections, five digital well logs, and core samples of 75 ft (ft = 0.3048 m) length were used to build 3D models for the Matulla reservoir. The 3D structural model shows strong lateral variation in thickness of the Matulla Formation with NW–SE, NE–SW and N–S fault directions. According to the 3D facies model, shale beds dominate the Matulla Formation, followed by sandstone, carbonate, and siltstone beds. The petrophysical model demonstrates the Matulla reservoir's ability to store and produce oil; its upper and lower zones have good quality reservoir, whereas its middle zone is a poor quality reservoir. The most promising areas for hydrocarbon accumulation and production via the Matulla reservoir are located in the central, southeast, and southwest sectors of the oilfield. In this approach, we combined multiple datasets and used the most likely parameters calibrated by core measurements to improve the reservoir modeling of the complex Matulla reservoir. In addition, we reduced many of the common uncertainties associated with the static modeling process, which can be applied elsewhere to gain better understanding of a complex reservoir. [ABSTRACT FROM AUTHOR]

Radiation shielding performance against gamma rays for four mineralized natural rock samples collected from Um Bogma area, Southwestern Sinai, Egypt was determined by Monte-Carlo simulation, theoretical calculations and confirmed by experimental evaluations. The Monte Carlo simulation was utilized to investigate the shielding capacity of the investigated rock samples in the energy range between 0.015 and 15 MeV. According to the Monte Carlo simulation the best shielding properties were achieved for sample siltstone S22 which contains (Fe–Mn) mineralization and density of 3.85 (g/cm3), where the simulated linear attenuation coefficient decreased from 71.30 cm−1 to 0.09 cm−1, increasing the incident gamma photon energy between 0.015 and 15 MeV. On the other hand, the lowest gamma ray shielding capacity achieved for sample siltstone S24 which rich in iron sulfate, with linear attenuation coefficient decreased from 37.50 cm−1 to 0.05 cm−1, increasing the incident gamma ray energy between 0.015 and 15 MeV, respectively. The gamma ray shielding properties for sample siltstone S22 were examined experimentally to confirm the simulated results. Both of experimental and simulated results are close together, with a difference of ±0.5%. Moreover, the siltstone S22 sample shows a thin half-value layer, high effective and equivalent atomic numbers as well as low EBF and EABF values. • The gamma-ray shielding features were examined for four various types of rocks. • The Monte Carlo (MC) simulation was utilized to evaluate the collected rocks' shielding capacity. • The siltstone sample containing (Fe–Mn) mineralization has the best shielding capacity. • The experimental measurement was performed for the sample with MC's best gamma-ray shielding capacity. [ABSTRACT FROM AUTHOR]

Thermoluminescence ( TL) dating has been used to determine the age of the meteorite impact crater at Gebel Kamil (Egyptian Sahara). Previous studies suggested that the 45 m diameter structure was produced by a fall in recent times (less than 5000 years ago) of an iron meteorite impactor into quartz-arenites and siltstones belonging to the Lower Cretaceous Gilf Kebir Formation. The impact caused the complete fragmentation of the impactor, and the formation of a variety of impactites (e.g., partially vitrified dark and light materials) present as ejecta within the crater and in the surrounding area. After a series of tests to evaluate the TL properties of different materials including shocked intra-crater target rocks and different types of ejecta, we selected a suite of light-colored ejecta that showed evidence of strong thermal shock effects (e.g., partial vitrification and the presence of high-temperature and -pressure silica phases). The abundance of quartz in the target rocks, including the vitrified impactites, allowed TL dating to be undertaken. The variability of radioactivity of the intracrateric target rocks and the lack of direct in situ dosimetric evaluations prevented precise dating; it was, however, possible to constrain the impact in the 2000 BC-500 AD range. If, as we believe, the radioactivity measured in the fallback deposits is a reliable estimate of the mean radioactivity of the site, the narrower range 1600-400 BC (at the 2σ confidence level) can be realistically proposed. [ABSTRACT FROM AUTHOR]

Abstract: Lower Paleozoic rocks are exposed in various regions of Egypt (south central Sinai, north Eastern Desert and southwest Western Desert), in addition to occurring in the subsurface such as north Western Desert and the Gulf of Suez. The Lower Paleozoic rocks in Egypt include surface and subsurface rock units of formational status. The surface rock units are the Taba, Araba and Naqus formations. The subsurface rock units include the Shifa, Kohla and Basur formations. The Infracambrian Taba Formation has been discovered recently in the outcrops of the southeast central Sinai in the Taba-Ras El-Naqab area. It is missing and/or not recognized in the subsurface. The Taba Formation consists mainly of reddish brown, unfossiliferous gravelly fine- to medium-grained kaolinitic sandstones and subordinate horizons of paleosols. The Cambrian Araba Formation and its subsurface equivalent (the Shifa Formation) are essentially composed of reddish brown, fine-grained laminated sandstone and siltstone with abundant Skolithos and Cruziana sp. In contrast, the Ordovician–Silurian Naqus Formation and its subsurface equivalents (the Kohla Formation and Basur Formation) are mainly composed of white, unfossiliferous, cross-bedded, medium- to coarse-grained sandstones with haphazardly distributed pebbles and cobbles. Sedimentological analysis indicates that the Araba Formation and its subsurface equivalent were deposited in a marginal-marine environment, whereas the Naqus Formation and its subsurface equivalents were laid down in a fluvio-glacial environment. Integrated stratigraphic and sedimentological studies of the Lower Paleozoic rocks permit reconstruction of the paleogeography of Egypt at that time. Egypt has been largely controlled since the Cambrian by the pre-existing structural framework of the pre-Phanerozoic basement rocks inherited from the Late Proterozoic Pan-African event. Additionally, sedimentation processes were controlled during Cambro-Ordovician times by tectonic movements, whereas glacio-eustatic control predominated during the Late Ordovician–Silurian Period. These studies suggest that most areas of Egypt were exposed lands with episodically transgression by epi-continental seas related to the paleo-Tethys. These lands formed a part of a stable subsiding shelf at the northern Gondwana margin. [Copyright &y& Elsevier]

Abstract: Petrography, mineralogy and chemical analyses were combined to investigate the lower Paleozoic sandstones at Wadi El-Quseiyeb area, East Sinai. They are mainly classified texturally as silty sandstones, sandstones and clayey siltstone. Their average modal composition (QFL, 87:11:2), classifies them as quartz arenite and arkosic arenite, with high proportions of quartz, monocrystalline quartz grains, more potash feldspar than plagioclase and a low plagioclase/total feldspar ratio (P/F <0.2). High SiO2, K2O>Na2O, and low Fe2O3 +MgO values revealed by chemical analyses are consistent with the modal data. Other criteria include elevated Ba and Sr contents and depletion in the ferromagnesian elements. The petrography and geochemistry suggest a stable continental (passive) margin or intracratonic basin, analogous to that of an Atlantic-type continental shelf. Also, they reflect a stable craton interior source, devoid, to a large extent, of basic debris and ultimately derived from a low-lying granite-rich Precambrian craton. Chemical index of alteration (CIA) and the Plagioclase index of Alteration (PIA) values range from 57.2 to 93.0 and from 79.7 to 94.6, respectively. However, most samples have values more than 60, suggesting a moderate to relatively high degree of alteration (weathering) in the source area. [Copyright &y& Elsevier]

A total of 78 sandstone core samples were obtained from the NES-2 well of the SWS field in the Abu Sennan area to assess the reservoir properties of the Middle Zone of the Bahariya Formation. It comprises carbonate, silt, and shale with sandstone interbeds, where the sandstone was targeted as it represents the main production zone in the studied area. The studied samples were subjected to porosity and permeability measurements, where the relationship between them showed the reservoir heterogeneity in terms of flow properties. Capillary pressure correlations displayed four hydraulic flow units with different performances within the studied samples in accordance with r35 parameter classification. The very permeable flow unit (megaport) constitutes 92% of the total flow capacity. Other petrophysical parameters such as apex, pore throat radii, reservoir quality index (RQI), and turbulence factor (β) were used to confirm the previous results and deeply evaluate the studied reservoir samples. Petrographically, the Middle Zone of the Bahariya Formation is represented by intercalations of siltstone, quartz arenite (the common facies), quartz wacky, and sandy siltstone facies from base to top. These microfacies represent the different petrophysical flow units. In terms of log evaluation, the middle zone of the Bahariya sandstone reservoir is characterized by a net pay thickness of about 6.9 m in the NES-2 well and marked by (Vsh = 0.05, φE = 0.24, and Sw = 0.4) as an oil producer. All the results were consistent and confirmed that the Middle Zone of the Bahariya Formation has excellent reservoir capabilities. Megaport flow units of the highest flow rate nature are predominant and nearly constitute the flow capacity, hence the reservoir may suffer some productivity loss under the turbulence flow conditions or the moving fines. • Middle Zone Bahariya Fm. is an excellent reservoir at Abu Sennan area. • Four flow units were discovered within Middle Zone Bahariya Fm. • Megaport flow unit constitutes 92% of the flow capacity. [ABSTRACT FROM AUTHOR]