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The magmatic complex along the Marsa Alam-Idfu transect, Central-Eastern Desert of Egypt, represents the northern segment of the Arabian–Nubian Shield (ANS), which developed within the framework of the East African Orogen. The basement rocks of the Arabian-Nubian Shield have been developed through three distinct phases of magmatic activity: the island-arc, the syn-orogenic, and the post-orogenic phases. Transitioning of the magmatic phases from the syn-orogenic to the post-orogenic, identifies changing the tectonic regime from a compressional to an extensional setting. The scarcity of comprehensive regional geochronological data that rely on precise isochron methods, such as the zircon U-Pb technique, could limit the comprehensive understanding of this region's geological and tectonic history. That would raise a number of uncertainties ranging from the timing of the different magmatic activities and timing of changes in the tectonic regime to the existence of the pre-Pan-African crust in the CED. Our study provides new insights into the aforementioned uncertainties through zircon U-Pb dating of different rock units along the Marsa Alam-Idfu transect, CED, Egypt. The resulting ages ranged from 729 ± 3 Ma to 570 ± 2 Ma, constraining the temporal evolution of the ANS in the studied region into (1) the island-arc phase, represented by a metamorphic sample with an age of 729 ± 3 Ma. (2) the syn-orogenic phase, represented by calc-alkaline and alkaline granitic samples with ages ranging from 699 ± 4 Ma to 646 ± 2 Ma. These two phases indicate initiation of the compressional subduction regime in the CED since 729 ± 3 Ma and being dominated till 646 ± 2 Ma. (3) the post-orogenic phase, represented by metavolcanics, volcanic rocks, and alkaline plutonic samples with ages ranging from 623 ± 3 Ma to 570 ± 2 Ma. This phase suggests dominance of the compressional-to-extensional tectonic transition setting from 623 ± 3 Ma to 600 ± 1 Ma along with the Dokhan volcanism and activation of post-collision tensional regime activated at 582 ± 3 Ma. Our findings discourage the proposed dominance of the island-arc and syn-orogenic phases in the CED and the classical restriction of older magmatic activity to calc-alkaline granitic rocks and younger magmatic activity to alkaline granitic rocks. Additionally, we identified evidence of local magmatic sources by dating five grains with Mesoproterozoic (pre-Arabian–Nubian Shield) xenocrysts with ages ranging from 1549 ± 4 to 1095 ± 25 Ma. [ABSTRACT FROM AUTHOR]

ABSTRACT This research focuses on the field observations, petrography, mineral chemistry and geochemistry of the serpentinised peridotite of Al‐Barramiya ophiolitic sequence to place constraints on their magmatic history and their geodynamic evolution. Al‐Barramiya ophiolitic rocks are a dismembered ophiolite which was strongly deformed and metamorphosed under greenschist to lower amphibolite facies. They comprise a mantle section dominated by highly serpentinised peridotite with less metapyroxenite and chromitite, as well as a crustal portion represented by metagabbros. Along shear zones, the ophiolite sequence was affected by several types of alteration. Extensive carbonate alteration is common in the ultramafic section, resulted in talc carbonates, listvenites and magnesite, while rodingitisation is common in the metagabbro resulted in rodingite. Despite the extensive serpentinisation, some fresh relics of primary mantle minerals such as Cr‐spinel, olivine and pyroxenes are preserved sporadically in the serpentinised peridotite. Few Cr‐spinel crystals are sometimes surrounded by subhedral flakes of Cr‐chlorite (kämmererite) that was formed due to replacement of Cr‐spinel during later alteration or regional metamorphism. The serpentinite samples are depleted in the total REE (0.56–1.19 ppm) with slightly negative to slightly positive Eu anomalies (0.89–1.28). The fresh cores of Cr‐spinel have Cr# mostly > 60, and the relics of pyroxenes and olivine are Mg‐rich suggesting that the Al‐Barramiya serpentinites are residual to high degrees of melt extraction. The estimated degrees of partial melting range between 18.2% and 20.7%. All the mineralogical and geochemical characteristics of the ultramafic section of the Al‐Barramiya ophiolites are most consistent with its formation in a fore‐arc setting. [ABSTRACT FROM AUTHOR]

Most of Africa's illegal mining operations are conducted in rural areas, but along the Red Sea coast, they primarily occur in the Eastern Desert, where they are regarded as the major source of revenue. Soil samples were collected and examined at an illegal gold mining site in the far south of Egypt's Eastern Desert to determine the toxicity levels of eight heavy metals for pollution load index (PLI), Igeo, and health (Au, Ag, As, Hg, Ni, Cr, Zn, and Pb). The methodology used in this study was categorized into fieldwork with restricted rules within the visit, soil samples collected from the field, chemical analyses for heavy metals, and statistical analyses by applying six equations to define the environmental status of the study area. It was found that the PLI increases contamination as an environmental risk grade, Igeo, reaches grade 6, which is highly contaminated, and the average hazard index (HI) for the individual elements is high (>0.01). The health risk assessment results for Ni and Cr showed that oral intake was the main mode of exposure to heavy metals in the tailings of illegal mines. In addition, the average levels of As, Hg, Cr, Ni, Pb, and Zn were higher than the equivalent background levels for soils. Thus, adult cancer risk (CR) exceeds the permissible level of 10−4. The illicit mining activities in the Eastern Desert also resulted in heavy metal contamination with substantial noncarcinogenic hazards for As and Zn, necessitating urgent remediation. [ABSTRACT FROM AUTHOR]

The present work deals with the investigation of the mineralogical characteristics of stream sediments, as possible source of economic heavy minerals. Their heavy minerals content was separated and identified, and the most abundant economic heavy minerals are ilmenite, magnetite, garnet, rutile, leucoxene, zircon, monazite, and cassiterite. Besides the identified economic heavy minerals, some radioactive and REE-bearing minerals were found too including: thorite, xenotime, and chernovite. Also, fluorite, apatite and gold occur in the sediments. The studied stream sediments are characterized by moderate concentrations of major oxides and trace elements commonly associated with mafic rocks, and high concentrations of those associated with felsic rocks, suggesting that they were derived from different sources. The existence of some elements was interpreted in terms of their occurrence in the structure of the recorded accessory minerals such as Th, Zr, and Y. The low values of the Cr/V ratio of the stream sediments (Average = 0.48) indicate a negligible contribution from ultrabasic sources. The radioactivity measurements show a predominance of thorium over uranium as these sediments are most likely pronounced natural trap for the thorium minerals such as thorite and monazite. The low values of eU/eTh ratio (average = 0.17) indicate the removal of uranium due to supergene processes. [ABSTRACT FROM AUTHOR]

The Fawakheir-Attala gold mining zone in Egypt's Central Eastern Desert features a diverse range of rock formations, including Precambrian crystalline rocks and Phanerozoic sedimentary formations. These formations encompass gneisses, metavolcanics, metasediments, a metagabbro-diorite complex, Dokhan volcanic rocks, and granitic rocks, alongside lower and upper Nubia sandstones. Faults and shear zones are pivotal in controlling gold mineralization within the area, indicative of substantial mineral wealth. This study aimed to map subsurface structural characteristics and investigate gold mineralization zones using aerial magnetic data and ASTER remote sensing, the latter of which played a crucial role in highlighting the surface exposure of alteration zones. Geological surveys combined with remote sensing techniques were employed to identify rock types and mineralization zones, while magnetic methods, including aeromagnetic surveys and ground-based studies, were used to reveal underlying structural properties and fault systems. Analysis of aeromagnetic data revealed a large mineralization zone running from the Fawakhir Gold mine through the Attala Gold mine in a NW–SE direction. Various structural trends and faults, including NW–SE, NE–SW, E–W, and N–S directions, were identified, strongly associated with hydrothermal alteration zones and gold mineralization. Shallow basement relief was observed in the eastern and central regions, contrasting with deeper formations and greater relief in the western section. Land magnetic surveys were utilized to identify new areas for gold mineralization, with geochemical analysis confirming gold content in quartz veins and host rocks. The integration of magnetic and remote sensing techniques effectively highlighted alteration zones indicative of potential mineralization, which could have a subsurface continuation, aiding in the identification of gold occurrences connected to faults, lineaments, and mineralization zones. [ABSTRACT FROM AUTHOR]

Abstract The South Eastern Desert (SED) of Egypt is one of the most promising areas in Egypt; it is widely explored for exploring the rare earth elements (REEs) and uranium-bearing ores. It is a main part of the Arabian-Nubian Shield (ANS). Therefore, the present study concerns with Sikait-Nugrus area as one of the most prolific sites in this region. The study provides a detailed geological, structural, and mineralogical investigation of the monzogranites to describe and characterize the various alteration types and sequence. For this purpose, remote sensing, geochemical and petrographical techniques were applied. The remote sensing technique helped in constructing a detailed geologic map of the study area to follow up strictly the alteration zone of the Sikait-Nugrus area. Petrographically, the granites predominates in the study area, they are described as slightly and highly altered monzogranites. The slightly altered one is composed mainly of quartz (~ 20–35%), alkali feldspar (~ 25–30%), plagioclase (~ 25–30%), and mica (~ 5–15%), while accessory minerals are represented by zircon and monazite. On the other hand, the portion of this granite close to the shearing zone is intensively altered and characterized by sericitization as the main alteration processes. This sheared portion is characterized by accessory minerals as, uranothorite, allanite, fluorite and Nb-minerals (ishikawaite). Minerlogically, the altered monzogranites are predominated by the following mineral groups: (1) radioactive minerals as uranyl silicates (soddyite, uranophane and kasolite), and thorium minerals (thorite and uranothorite), (2) Nb–Ta minerals (betafite, plumbobetafite, columbite, fergusonite, and aeschynite), (3) REE minerals (monazite, cheralite and xenotime), and (4) zircon and fluorite as accessory minerals. Geochemically, the recorded pattern of the REEs tetrad effect (M-type) for the highly altered samples indicate that these granites are highly evolved and affected by late stage of hydrothermal alteration and the effective water-rich alteration processes that connected to intensive physico-chemical changes. The total REE concentrations equal 241.8 and 249.75 ppm for the highly and slightly altered samples. A significant mass change (MC) was analyzed by the isocon technique (22.95 & 11.11) and volume change (VC) (1.8 &-7.99) for the highly and slightly altered samples, respectively. The mass balance calculations and the isocon diagrams revealed that some major oxides were removed from the slightly altered monzogranites and transformed later into highly altered monzogranites with increasing the alteration intensity due to the impacts of hydrothermal alteration processes. The studied area is virgin, where no detailed studies have been applied to this region. It is extendable to other parts of the Arabian-Nubian Shield in around the Red Sea in Egypt, Sudan, Saudi Arabia and Yemen. The applied technical workflow is also extendible to other surface analogues everywhere.

Abstract This study presents a comprehensive analysis of mineralization exploration in the Egyptian Eastern Desert (ED), one of the most sought-after areas for those interested in mining industry, by integrating Landsat-9 images and geophysical magnetic data. Employing advanced techniques like Principal Component (PC) analysis, Minimum Noise Fraction (MNf) transform, and Band-Ratio (B-Ratio), the research focuses on mapping lithological units, hydrothermal alteration regions, and structural elements. Composite images derived from specific PC, and MNf bands, and B-Ratio exhibit superior lithological unit identification. The findings emphasize that there are significant variations in the types of rocks extend from the southern to the northern parts of the ED. Hydrothermal alteration mapping, guided by B-Ratio results, aids qualitative lithological discrimination. A novel false color composite image optimizes Landsat-9 B-Ratios, enhancing rock unit discrimination. Correlation analyses reveal associations between mineralization types and major lithological units, while exploration of the magnetic anomaly map highlights its role in correlating mineralization sites. Structural features, analyzed through Center for Exploration-Targeting Grid-Analysis (CET-GA) and Center for Exploration-Targeting Porphyry-Analysis (CET-GA) with Tilt Derivative of RTP (TDR) techniques, contribute to a robust association between regions with medium to high structural density and porphyry intrusions and mineralization. The study significantly supports the advanced exploration geoscience, providing insights into the geological structures and dynamics governing mineralization in the Egyptian ED.

The South Eastern Desert (SED) of Egypt is one of the most promising areas in Egypt; it is widely explored for exploring the rare earth elements (REEs) and uranium-bearing ores. It is a main part of the Arabian-Nubian Shield (ANS). Therefore, the present study concerns with Sikait-Nugrus area as one of the most prolific sites in this region. The study provides a detailed geological, structural, and mineralogical investigation of the monzogranites to describe and characterize the various alteration types and sequence. For this purpose, remote sensing, geochemical and petrographical techniques were applied. The remote sensing technique helped in constructing a detailed geologic map of the study area to follow up strictly the alteration zone of the Sikait-Nugrus area. Petrographically, the granites predominates in the study area, they are described as slightly and highly altered monzogranites. The slightly altered one is composed mainly of quartz (~ 20–35%), alkali feldspar (~ 25–30%), plagioclase (~ 25–30%), and mica (~ 5–15%), while accessory minerals are represented by zircon and monazite. On the other hand, the portion of this granite close to the shearing zone is intensively altered and characterized by sericitization as the main alteration processes. This sheared portion is characterized by accessory minerals as, uranothorite, allanite, fluorite and Nb-minerals (ishikawaite). Minerlogically, the altered monzogranites are predominated by the following mineral groups: (1) radioactive minerals as uranyl silicates (soddyite, uranophane and kasolite), and thorium minerals (thorite and uranothorite), (2) Nb–Ta minerals (betafite, plumbobetafite, columbite, fergusonite, and aeschynite), (3) REE minerals (monazite, cheralite and xenotime), and (4) zircon and fluorite as accessory minerals. Geochemically, the recorded pattern of the REEs tetrad effect (M-type) for the highly altered samples indicate that these granites are highly evolved and affected by late stage of hydrothermal alteration and the effective water-rich alteration processes that connected to intensive physico-chemical changes. The total REE concentrations equal 241.8 and 249.75 ppm for the highly and slightly altered samples. A significant mass change (MC) was analyzed by the isocon technique (22.95 & 11.11) and volume change (VC) (1.8 &-7.99) for the highly and slightly altered samples, respectively. The mass balance calculations and the isocon diagrams revealed that some major oxides were removed from the slightly altered monzogranites and transformed later into highly altered monzogranites with increasing the alteration intensity due to the impacts of hydrothermal alteration processes. The studied area is virgin, where no detailed studies have been applied to this region. It is extendable to other parts of the Arabian-Nubian Shield in around the Red Sea in Egypt, Sudan, Saudi Arabia and Yemen. The applied technical workflow is also extendible to other surface analogues everywhere. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive analysis of mineralization exploration in the Egyptian Eastern Desert (ED), one of the most sought-after areas for those interested in mining industry, by integrating Landsat-9 images and geophysical magnetic data. Employing advanced techniques like Principal Component (PC) analysis, Minimum Noise Fraction (MNf) transform, and Band-Ratio (B-Ratio), the research focuses on mapping lithological units, hydrothermal alteration regions, and structural elements. Composite images derived from specific PC, and MNf bands, and B-Ratio exhibit superior lithological unit identification. The findings emphasize that there are significant variations in the types of rocks extend from the southern to the northern parts of the ED. Hydrothermal alteration mapping, guided by B-Ratio results, aids qualitative lithological discrimination. A novel false color composite image optimizes Landsat-9 B-Ratios, enhancing rock unit discrimination. Correlation analyses reveal associations between mineralization types and major lithological units, while exploration of the magnetic anomaly map highlights its role in correlating mineralization sites. Structural features, analyzed through Center for Exploration-Targeting Grid-Analysis (CET-GA) and Center for Exploration-Targeting Porphyry-Analysis (CET-GA) with Tilt Derivative of RTP (TDR) techniques, contribute to a robust association between regions with medium to high structural density and porphyry intrusions and mineralization. The study significantly supports the advanced exploration geoscience, providing insights into the geological structures and dynamics governing mineralization in the Egyptian ED. [ABSTRACT FROM AUTHOR]

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield (ANS) in the Eastern Desert (ED) of Egypt comprises juvenile suites of metavolcanics (MV), large amounts of meta-sedimentary rocks (MS), and voluminous metagabbros-diorites (MGD) and syn-tectonic intrusions of older granitoids (OG). We report here the updates of these four rock units in terms of classification, distribution, chemical characteristics, geodynamic evolution, metamorphism, and ages. In addition, we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the ANS. The main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental arcs. Integrated information of the island arc metavolcanic and plutonic rocks (gabbros, diorites, tonalites, and granodiorites) furnish evidence of the genetic relationships. These include proximity and a coeval nature in the field; all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities; common geochemical signature of the arc rocks and subduction-related magmatism; their similar enrichment in LREEs; and similar major element compositions with mafic melts derived from metasomatized mantle wedge. The volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed slightly. Based on the magmatic, sedimentological, and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes, a possible gradual decrease in the subducted slab dip angle is the most influential in any geodynamic model for arc assemblage in the ED of Egypt. [ABSTRACT FROM AUTHOR]

The Nile Delta and Valley act as an important natural ecological barrier that the animals of the Western and Eastern Deserts cannot cross. For historical biogeographic reconstructions of arid habitats, the genus Acomys is an excellent model. Barriers that restrict the movement of animals allow for geographic isolation. In the present study, to investigate the evolutionary forces driving the differentiation of the Cairo spiny mice, Acomys cahirinus, particularly as related to the biogeographical relationship between the Western and Eastern Deserts of Egypt, thirty-eight skulls of male specimens of the Cairo spiny mouse from four different regions of Egypt that were kept in Al-Azhar University Zoological Collection in Cairo, Egypt were examined. Five of these skulls came from Bahariya Oasis, seven from Dakhla Oasis, five from Helwan region, and twenty-one came from Eastern Desert. Based on sixteen absolute cranial and dental measurements and seventeen ratios used here, A. c. helmyi from Dakhla Oasis differ greatly from those from Bahariya Oasis (A. c. cahirinus), Helwan region (A. c. cahirinus), and Eastern Desert (A. c. hunteri) populations. There were many cranial and dental characteristics correlated with each other. Most of these characteristics are highly positively correlated with body mass, condyloincisive length, and mastoid width. Despite the presence of this natural ecological barrier (the Nile Delta and Valley), a great similarity was found between the Cairo spiny mouse populations from Bahariya Oasis (Western Desert) and from Eastern Desert, noting the great difference between the Cairo spiny mouse populations from Dakhla Oasis (Western Desert) from the other populations in the present study. [ABSTRACT FROM AUTHOR]

Beryl mineralization in the Nugrus-Sikait domain in the South Eastern Desert (SED) of Egypt occurs as disseminated crystals in granitic pegmatite and quartz, as well as pegmatite veins crosscutting mélange schist and ophiolitic rocks. When granitic pegmatite comes into contact with the ophiolitic rocks, phlogopite and amphibole schists are formed due to K metasomatism. The ophiolitic mélange is intruded by leucogranite and related pegmatite along the NNW to NW Nugrus shear zone. Beryl samples have been collected from Um Sleimat, Madinat Nugrus, Wadi Abu Rusheid, and Wadi Sikait. Major oxides and in situ trace and rare earth elements (REEs) of beryl and associated minerals were analyzed through EPMA and LA-ICP-MS, respectively. The investigated beryl, based on its color and chemical compositions, can be classified into the two following types: pegmatitic beryl (type I) and schist-related beryl (type II). The former is colorless to pale green, and is mainly restricted in pegmatite veins; it is poor in Cr2O3 (up to 0.03 wt%) and MgO (Nil). The latter, deep green in color, is rich in Cr2O3 (up to 0.27 wt%) and MgO (up to 2.71 wt%), and occurs within quartz veins, phlogopite schists, and tremolite schists. The abundant beryl mineralization in phlogopite schists and their related quartz veins suggests that granite and associated pegmatite are the source rocks for the Be-bearing fluids that migrate along the NW-SE trending deep-seated tectonic zone, such as the Nugrus shear zone. Therefore, the formation of beryl in schists is attributed to the interaction of granitic/pegmatitic-derived Be-bearing fluids with serpentinite and gabbro interlayered with mélange schists. Variations in the trace and REE contents of both beryl types (I and II) indicate their two-stage formation from different compositions of Be-rich fluids, where light REEs, Zr, Nb, Ba, and Th decrease from type I beryl to type II. These two phases of beryl could be attributed to the magmatic/hydrothermal fluids associated with the pegmatite emplacement. The early phase of the late-stage magmatic-derived fluids was closely related to magma evolution and pegmatite formation, forming euhedral type I beryl. The late phase of pegmatite-derived fluids was mixed with serpentinite/schist-derived fluids that cause high V and Cr content in type II beryl. The composition of parent magmas of felsic rocks, the high degree of magma fractionation or the late stage melts, fluid compositions (rich in Be, Li, Cs, Rb, K), and alkali metasomatism, as well as the linear NW-SE trending deep-seated shear zone, are all factors possibly influencing beryl mineralization in the SED of Egypt. [ABSTRACT FROM AUTHOR]

Since the Middle Pleistocene, the Sahara region has undergone strong environmental changes resulting from climate changes. Dry periods, constituting an ecological barrier to human presence, alternated with wet periods when the Sahara area was covered with green savanna and an extensive network of watercourses, allowing the area to be occupied by hunter-gatherer groups. Responding to the Quaternary climatic changes, hominin dispersal was channeled through vegetated corridors. Such evidence for human settlements connected to Pleistocene green corridors in the Sahara region has been discovered in the research area called EDAR (Eastern Desert Atbara River). This area comprises a cluster of Acheulean and Middle Stone Age (MSA) sites discovered in the fluvial sedimentary context. This manuscript discusses the occurrence of Middle Pleistocene Acheulean artifacts in much younger sediments documented at the site EDAR 6. These Acheulean artifacts are present within thick Holocene calcareous sandy silts formed between 2.7 ka and 8.7 ka based on an optically stimulated luminescence (OSL) chronology, which is also supported by paleomagnetic analysis. The stone gravelly artifacts mantled above the eolian deposits have been known in other Paleolithic sites under the desert environment of Northern Africa. We propose that the relocation of the Palaeolithic artifacts was due to long-lasting erosional and redepositional processes affecting the Acheulean artifacts-bearing sediments since the Middle Pleistocene. We interpret that the cumulative results of the two processes, i.e., the gravel framework dilation and the gravel overpassing, allowed the stone artifacts to be exposed at the surface or incorporated in the Holocene sediment layers.

This study examines the accessory wodginite and the discovery of titanium-bearing wodginite and Fe and Ti-bearing wodginite in lithium-fluorine granites from the Abu Dabbab and Nuweibi massifs in Eastern Egypt. The wodginite group's mineral association includes tantalum-bearing cassiterite and tin-bearing tantalum–niobate minerals: tantalite-(Mn), columbite-(Mn), and microlite. Three forms of wodginite crystallization were identified: (1) rims around columbite-(Mn) and tantalite-(Mn) varying from 1.5 to 21.9 μm in thickness, (2) micro-inclusions in cassiterite ranging from 5.4 to 27.0 μm in size, and (3) autonomous crystals measuring 3–124 μm in length. Wodginite in the Nuweibi massif is mainly found in porphyritic granite of late-stage porphyry intrusion. It has a similar composition to the worldwide wodginite of rare-metal granites, but exhibits a lower content of TiO2 (average 0.54%) and is a mineral indicator of rich tantalum ore deposits. In contrast, wodginite in the Abu Dabbab massif is replaced by titanium-bearing wodginite (Ti/(Sn + BTa + Ti + Fe3+) = 0.23) and is associated with Fe and Ti-bearing wodginite. Wodginite and Ti-bearing wodginite are maximally enriched in manganese (Mn/(Mn + Fe2+ +Ca) = 0.95), expressed in all intrusive phases of the massif, and are mineral indicators of tantalum-bearing granites with associated cassiterite-quartz mineralization. [ABSTRACT FROM AUTHOR]

Beryl mineralization represents one of the most significant gemstones. The radioactive concentrations of 238U, 232Th, and 40K in beryl-bearing rocks in South Sinai, Central and South Eastern Desert, Egypt were measured using a portable RS230 gamma spectrometer. 238U (40 ± 14), 232Th (51 ± 19), and 40K (1176 ± 277 Bq/kg) are recorded for Ghazala, 54 ± 16, 36 ± 12, and 921 ± 243 Bq/kg for Sedri, 39 ± 15, 27 ± 12, and 842 ± 356 Bq/kg for Igla, 69 ± 16, 34 ± 3, and 1572 ± 83 Bq/kg for Homrit-Akarem, 89 ± 21, 130 ± 16, and 1439 ± 175 Bq/kg for Homrit-Mikpid, and 35 ± 13, 21 ± 12, and 940 ± 645 Bq/kg for Zabara-Um Addebaa. Radiological risk assessment parameters (e.g., annual effective dose, radium equivalent activity) were estimated to deduce the radiation effects on human organs. The obtained results are within acceptable limits. [ABSTRACT FROM AUTHOR]

New geochemical data of the Iron Oxide-Copper–Gold (IOCG) mineralization and its host rocks in the Dara area, North Eastern Desert of Egypt, are investigated for a better understanding of their petrogenesis. The host rocks are classified into metagabbro-diorite and I-type younger granitoids (monzogranite and alkali feldspar granites). The metagabbro-diorite rocks are volcanic arcs with calc-alkaline affinity and were generated by partial melting of mantle related to the subduction zone. The monzogranite and alkali feldspar granite are metaluminous to weakly peraluminous with calc-alkaline and highly fractionated I-type affinity, respectively. The monzogranite was suggested to be generated from the partial melting of the lower mafic crust, whereas the alkali feldspar granites were from the upper continental crust. IOCG mineralization at the Dara prospect is confined along contacts between the metagabbro-diorite and monzogranite rock types in the form of quartz and quartz-carbonate veins surrounded by alteration zones. The IOCG mineralization is structurally controlled where the quartz and quartz-carbonate veins follow rejuvenation NW–SE compressional Najd fault to E-W and NE-SW extensional fault systems. The hydrothermal mineralization consists of magnetite, hematite, specularite, quartz, calcite, chalcopyrite, minor pyrite, and native gold. Hydrothermal alteration is subdivided into inner sericite-rich and outer chlorite-rich zones. Chemical discrimination using CCPI (chlorite-carbonate-pyrite chemical index), AI (alteration index), and mass balance calculation suggests a redistribution of most elements during alteration without extensive elemental changes except for Eu and Ho. The field, mineralogical, and geochemical features advocated that the mineralization is akin to be related to the Iron Oxide-Cu-Au (IOCG) system that could be linked to the post-collisional tectonic setting of the Arabian-Nubian Shield (ANS). [ABSTRACT FROM AUTHOR]

Introduction: Rodents are the best-studying mammalian species in terms of classification and biology (histological structure and physiology). Gerbils, mice, and rats are the favorite mammal species for most studies due to their small size, short lifespan, and rapid reproduction. Aim of the Work: We tried to demonstrate the kidney histological structure and functions, oxidative stress, and immunohistochemical expression of Gerbillus pyramidum, Mus musculus, and Rattus norvegicus collected from three different habitats. Materials and Methods: We collected 21 live specimens; 7 of G. pyramidum from the New Valley region, 8 of M. musculus from the Faiyum region, and 6 of R. norvegicus from the Eastern Desert region. Results: G. pyramidum recorded six significantly increased biochemical parameters which are ALT, AST, cholesterol, triglycerides, sodium, and chloride. Also, M. musculus recorded six significant increase in the values of urea, creatinine, uric acid, alkaline phosphatase, calcium–ionized, and phosphorous. Total protein, potassium, calcium, and magnesium were the four biochemical parameters recorded as significant increase for R. norvegicus. The results confirmed that the New Valley region gerbils, who live in a desert arid area, have kidneys that are more efficient than those that live in Faiyum and Eastern Desert regions. The greater relative medullary thickness 2.83±0.45 was recorded for New Valley gerbils and the lowest one was 2.15±0.50 for Faiyum mice. The average juxtamedullary glomeruli diameter was greater 1.63 times than superficial glomeruli of G. pyramidum, 1.45 times of M. musculus, and 1.29 times of R. norvegicus. The highest values of the kidney GSH, SOD, and CAT were recorded for G. pyramidum, and the minimum values of the kidney GSH, SOD, and CAT were recorded for M. musculus. Weak expression of both anti-apoptotic protein bcl2 and pro-apoptotic protein p53 was observed for rodents’ kidney tissues from New Valley and Eastern Desert Regions but the Faiyum mice recorded positive strong immunoreactivity of bcl2 and moderate positive reactivity of p53 for cortex and strong expression for medulla of kidney tissues. Conclusion: G. pyramidum from the New Valley region has the highest RMT, superficial glomerular number, diameter, volume, RGBV, juxtamedullary glomerular number, and RGBV than other studied rodents. [ABSTRACT FROM AUTHOR]

Beryl mineralization in the Nugrus-Sikait domain in the South Eastern Desert (SED) of Egypt occurs as disseminated crystals in granitic pegmatite and quartz, as well as pegmatite veins crosscutting mélange schist and ophiolitic rocks. When granitic pegmatite comes into contact with the ophiolitic rocks, phlogopite and amphibole schists are formed due to K metasomatism. The ophiolitic mélange is intruded by leucogranite and related pegmatite along the NNW to NW Nugrus shear zone. Beryl samples have been collected from Um Sleimat, Madinat Nugrus, Wadi Abu Rusheid, and Wadi Sikait. Major oxides and in situ trace and rare earth elements (REEs) of beryl and associated minerals were analyzed through EPMA and LA-ICP-MS, respectively. The investigated beryl, based on its color and chemical compositions, can be classified into the two following types: pegmatitic beryl (type I) and schist-related beryl (type II). The former is colorless to pale green, and is mainly restricted in pegmatite veins; it is poor in Cr2O3 (up to 0.03 wt%) and MgO (Nil). The latter, deep green in color, is rich in Cr2O3 (up to 0.27 wt%) and MgO (up to 2.71 wt%), and occurs within quartz veins, phlogopite schists, and tremolite schists. The abundant beryl mineralization in phlogopite schists and their related quartz veins suggests that granite and associated pegmatite are the source rocks for the Be-bearing fluids that migrate along the NW-SE trending deep-seated tectonic zone, such as the Nugrus shear zone. Therefore, the formation of beryl in schists is attributed to the interaction of granitic/pegmatitic-derived Be-bearing fluids with serpentinite and gabbro interlayered with mélange schists. Variations in the trace and REE contents of both beryl types (I and II) indicate their two-stage formation from different compositions of Be-rich fluids, where light REEs, Zr, Nb, Ba, and Th decrease from type I beryl to type II. These two phases of beryl could be attributed to the magmatic/hydrothermal fluids associated with the pegmatite emplacement. The early phase of the late-stage magmatic-derived fluids was closely related to magma evolution and pegmatite formation, forming euhedral type I beryl. The late phase of pegmatite-derived fluids was mixed with serpentinite/schist-derived fluids that cause high V and Cr content in type II beryl. The composition of parent magmas of felsic rocks, the high degree of magma fractionation or the late stage melts, fluid compositions (rich in Be, Li, Cs, Rb, K), and alkali metasomatism, as well as the linear NW-SE trending deep-seated shear zone, are all factors possibly influencing beryl mineralization in the SED of Egypt.

I discuss two near-identical passages preserved on ostraca from the Eastern Desert (O.Claud. 1.141, ll. 1–4 and O.Claud. 1.142, ll. 1–3). Although they seem to provide an insight into how speakers of Greek in the first centuries AD perceived the relationship between finite and non-finite clauses, their interpretation turns out to be an intricate task. This is because the authors of most texts from the area were L2 speakers of Greek (Leiwo, ‘L2 Greek in Roman Egypt’). Based on the concept of authenticity (Joseph, ‘Textual Authenticity: Evidence from Medieval Greek’), I nonetheless argue that the passages in question reflect the wider processes that took place in Koine, resulting in the use of the perfect infinitive to convey anteriority in the infinitive clauses dependent on verbs of saying and thinking. [ABSTRACT FROM AUTHOR]

Fused remote sensing datasets have greatly contributed to enhancing lithological targets and providing significant information for mineral exploration. For instance, multispectral datasets can discriminate rock units through their unique spectral signatures. Digital Elevation Models (DEMs) could be an effective tool boosting lithological discrimination based mainly on their topographic variations. Consequently, the current study applied the power of the support vector machine (SVM) algorithm and the integrated Phased Array L-type band Synthetic Aperture Radar (PALSAR) DEM and multispectral Sentinel 2 data to: 1—Create an updated lithological map of a poorly mapped arid terrain (Khashir-Ras El-Kharit district, Eastern Desert of Egypt), and 2—Compare and assess the distribution of ferrogabbros with the aim of improving the localization of these rock bodies and investigating their mineral content. Our results enhanced the lithological mapping and revealed a better generalization of mineralized ferrogabbros when the input was a fused DEM with Sentinel 2 compared to the salt and pepper effect observed when adopting the Sentinel 2 solely as the input data. Additionally, the current research strongly recommends detailed exploration programs for Fe-Ti oxide ores within the gabbroic rocks delineated through the resultant thematic map. The ferrogabbros were subjected to a comprehensive analysis involving whole rock geochemistry, XRD, EDX, and light-reflecting investigations, which revealed the existence of magnetite, titanomagnetite, and hematite. The titanomagnetite crystals display subhedral morphology and exhibit fine- to medium-grained surfaces with irregular shapes. X-ray diffraction (XRD) analysis revealed the presence of magnetite and hematite in the concentrated Fe-Ti oxides. Additionally, the whole rock geochemistry highlighted the origin of the ferrogabbros and their proposed tectonic setting as an alkaline to calc-alkaline magma type that developed in a continental arc setting. [ABSTRACT FROM AUTHOR]

The Sudanese Eastern Desert or the 'Atbai' is still largely unexplored from the point of view of rock art surveys. As part of the Atbai Survey Project's fieldwork program, surveys conducted in 2018 and 2019 identified new rock art sites in the deserts around Gebel Nahoganet. Findings included a large tableau of a boat 'fleet' along with numerous sites yielding faunal rock art and surface remains. While a generalized boat motif is relatively commonplace in the corpus of rock art from Egypt and Nubia, this specific type of boat encountered in this distant desert exhibits a number of unique features. Notably, the tableau is carved within the walls of a natural tunnel and the features and manner of its execution have few parallels elsewhere. This contribution introduces the hypothesis that these boat motifs may have been the products of local Nubian groups including the A-Group horizon (c. 3800–3100 BCE). [ABSTRACT FROM AUTHOR]

Through various scales of observation, ranging from remote sensing data, field investigations, hand specimens, microscopic petrographic examinations, XRD, to SEM, indicators of various mineralization types are highlighted in Ras El-kharit-wadi Khashir (Eastern Desert, Egypt). Systematic remote sensing exploration of the mineralized zones is performed through integrating Sentinel 2 and ASTER datasets. False-color combinations, informative band ratios, relative absorption band depth, and CEM techniques were applied to discriminate rock units and various types of hydrothermal alterations. Moreover, ALOS PALSAR DEM was utilized to decipher the structural lineaments. Intensive field investigations confirmed hydrothermally altered zones that were picked out through remote sensing analysis and revealed that the study area is affected by cataclastic metamorphism to some extent. Magmatic and metamorphic rock types are represented by propylitic, phyllic, argillic, and silicification zones. Sericitization, chloritization, epidotization, kaolinitization, carbonatization, and silicification are recorded utilizing petrographic and remote sensing investigations. Moreover, the current study reveals that the detected alteration is the main reason for the apparent wide range of petrographic characteristics of each rock type and bearing several opaque minerals, such as pyrite, magnetite, titanomagnetite, chalcopyrite, arsenopyrite, covellite, galena, goethite, and hematite. Most of these opaques were identified using ore microscopy, XRD, and SEM. The distribution of hydrothermal alterations, representative samples bearing mineralization, structurally dissected zones are integrated to build a mineral potentiality map of the study area. The resultant MPM was confirmed via field survey and emphasized the usefulness of the current integrated approach besides highlighting about 125 km2 as potential mineralized zones.

Gold-sulfide mineralization in the Abu Zawal (Fatira) mine area, North Eastern Desert of Egypt, is related to porphyritic felsite dikes and elongate silicification zones in granitic rocks. These felsite dikes and the host granitic rocks exhibit major and trace element geochemical features typical of calc-alkaline and metaluminous I-type granites, likely originated in a late-orogenic setting. Their geochemical characteristics along with their fractionated LREE relative to HREE patterns imply either formation in a subduction-related environment or generation from subduction-modified source materials. Partial melting of subduction-metasomatized lower crustal rocks during extension following the lithospheric thickening may account for the production of such fertile, high Sr/Y and La/Yb magmas. In the Abu Zawal (Fatira) area, NE-trending altered felsite dikes, hydrothermal breccias, quartz enclaves, and wall-rock replacements are characterized by disseminations of chalcopyrite, pyrite, and rare gold. Alteration mineralogy, dominated by sericite, drusy quartz, kaolinite, calcite, and specular hematite, combined with the available fluid inclusion data suggests moderate to low temperature and near neutral pH conditions. The geochemical data of the altered wallrocks and mass balance calculations indicate significant mass losses in the altered rocks consistent with fluid/wallrock ratios higher than unity and near neutral pH conditions. Considering that the silica-rich host rocks, hydrothermal alteration, and sulfide-bearing hydrothermal quartz breccia in Fatira mine area were intuitively related to sulfur-saturated, oxidized felsic magmatism and associated hydrothermal systems, they are most likely linked to the post-subduction felsite porphyries (post-Hammamat felsites ~ 607 Ma), or pertaining to the late phases of the subaerial high-K calc-alkaline volcanics (Dokhan Volcanics ≤ 620 Ma). [ABSTRACT FROM AUTHOR]

The rapid expansion of economic activities in Egypt's Central Eastern Desert has resulted in poorly coordinated groundwater development, having a negative impact on the resource. This study was conducted to assess the hydrochemical characteristics of the different aquifers in the Central Eastern Desert, with an emphasis on the impact of seawater intrusion and groundwater quality for different purposes. A total of 21 groundwater samples were collected representing the three main aquifers (Eocene Carbonate, Nubian Sandstone, and Fractured Basement) in the Central Eastern Desert, and analyzed for major ions and trace elements. The majority of the samples had electrical conductivity values that exceeded the salinity limit for natural water. Groundwater saline load is primarily influenced by sodium, calcium, chloride, and sulfate concentrations. The groundwater in the Central Eastern Desert mainly consists of Na-Cl, Ca-Cl, and Na-SO4 water-types. Saltwater intrusion and water-rock interactions via cation exchange and minerals weathering are the primary controlling factors of groundwater hydrochemistry. The high salinity of this groundwater renders it unsuitable for irrigation or consumption. Additionally, it is unfit for domestic use based on total hardness values. Furthermore, the Al, Cd, Fe, Mn, and Ni concentrations in the investigated groundwater exceed the allowable limits for human consumption. Proper mitigation measures and adaptation strategies are required for groundwater sustainability in the Central Eastern Desert. [ABSTRACT FROM AUTHOR]

The Abu Ghalaga pluton in the southern eastern desert of Egypt (SED) consists of undeformed norite and hornblende gabbro intruding island arc metavolcanics, ophiolitic rocks, and syn-tectonic older granitic rocks. The Fe-Ti ore (mainly ilmenite) occurs in the form of lenses at the base of the norite. Based on microtextures, mineralogy, and chemical composition, three types of ilmenites are recognized: massive high-Mg type, disseminated high-Mg type, and disseminated low-Mg ilmenite. The three ilmenite types are chemically distinguished by their MgO, MnO, TiO2, Fe2O3, FeO, and V2O3 contents. The variations in the concentration of these oxides are interpreted as a function of variations in T, fO2, and the composition of the parental magma. Reconstruction of the orthomagmatic conditions shows that T and fO2 of the magma from which the norite and its Fe-Ti deposit formed decrease during the course of magmatic differentiation, whereas the hornblende gabbro and its Fe-Ti mineralization have formed from a more evolved magma under relatively lower T and fO2. The REE patterns and variation diagrams support a model of crystal fractionation as the primary means of formation of the Fe-Ti deposits. Chemical features also suggest that the parent magma of both types of gabbroic rocks was generated in the mantle, but in two different pulses. Subduction zone, MORB, and WPB chemical signatures for these gabbroic rocks suggest a complex tectonic history consistent with compression followed by within plate extension possibly contributing to the development of a back-arc/intra-arc basin. [ABSTRACT FROM AUTHOR]

The mantle rocks from Kadaboura and Madara areas represent sections of dismembered ophiolitic complexes developed during the Neoproterozoic in the Eastern Desert of Egypt, which is located in the northwestern corner of the Arabian–Nubian Shield. The Kadaboura mantle rocks comprise serpentinites and serpentinized dunites, whereas those of the Madara consist of serpentinites and serpentinized pyroxenites. Despite the serpentinization of the studied mantle rocks, few relicts of primary chromite, olivine and pyroxene are preserved. Chromite is partly altered having unaltered Al-rich chromite cores surrounded by Fe-rich chromite and Cr-rich magnetite rims. The unaltered Al-rich chromite cores show compositions equilibrated at temperatures mostly below ~500-600°C, which is a temperature comparable to that estimated for primary chromite in greenschist up to lower amphibolite facies rocks. The high Cr# [100×Cr/(Cr+Al)= 47-76] of the unaltered chromite cores and the Mg-rich nature of the olivine relicts (Fo91–94) indicate that the studied mantle rocks were produced from a highly depleted mantle that experienced high degrees of melt extraction (mostly ~30-40%). This range of melt extraction resembles that estimated for supra-subduction zone peridotites, but higher than that in abyssal and passive margin peridotites. Furthermore, the clinopyroxene relicts show compositions comparable to those from the Mariana forearc peridotites. Bulk-rock geochemistry also reflects derivation from an extremely depleted and a highly refractory mantle source. Modelling of rare-earth elements suggests that the studied mantle rocks were possibly formed by the interaction of their highly depleted harzburgitic mantle precursors with subduction-related melts/fluids during their evolution in a fore-arc basin of the supra-subduction zone. The proposed geodynamic model suggests that the oceanic lithosphere generated during the seafloor spreading of the Mozambique Ocean was emplaced in the upper plate of the intra-oceanic subduction zone, in which the formely depleted Neoproterozoic mantle of the Arabian-Nubian Shield experienced mature phases of hydrous melting, extreme depletion and enrichment.

The Neoproterozoic Arabian-Nubian Shield (ANS) in the Eastern Desert of Egypt encloses the regional thermal-tectonic history from its development till the Oligo-Miocene when the Red Sea rift system was initiated. The application of multi-thermochronometry techniques has proven to be a successful approach to revealing the influence and extent of each regional tectonic event and the recreation of the tectono-thermal development of the studied region through time. Therefore, characteristic samples from the ANS different rock suits of the Gabal Loman area at the western flank of the northern Red Sea were collected. The Zircon fission-track data reveals the Carboniferous cooling ages, while the apatite fission-track cooling ages present two differential time spans of Cretaceous and Eocene-Oligocene. The time-temperature history modeling is integrated with fission-track data to reveal three differentiated cooling events developed in response to regional tectonic events: 1) the Hercynian (Variscan) tectonic event that influenced the ANS vicinity with rock uplifts of ca. 4 km through the Devonian-Carboniferous time, 2) the Gondwana disintegration event which influenced the region with differential rock exhumations, and 3) the northern Red Sea rifting through the Oligo-Miocene which caused a regional ca. 1 km of rift flanks exhumation. This modest rift flank uplift suggests a passive rift of the northern Red Sea rifting in the region of study.

Recently, detecting the edges and geologic structures (deep and shallow) from potential field sources provides a fundamental tool for interpreting geological structures. Therefore, the high precision computation of the edges of potential sources is becoming an essential requirement for studying subsurface structures. In this study, nine common detectors like tilte angle (TA), Theta-map (TM), Horizontal tilt angle (TDX), hyperbolic tilt angle (HTA), Improved tilt angle (ITA), Tilt angle of the total horizontal gradient (TTHG), Tilt angle of the total gradient (TTG), improved Theta-map (ITM), and improved logistic (IL) were applied. These filters have been tested on theoretical models and real data (aeromagnetic) from the Wadi Umm Ghalqa area, South Eastern Desert of Egypt. The obtained results have shown that the improved logistic (IL) filter could detect edges more successfully than the other eight filters. The results of the IL method were used to generate new accurate structural maps for local and deep components of the investigated area. Moreover, surface structures obtained from remote sensing data were considered to control the interpretation of the mapped subsurface lineaments. Hence, the IL method can be utilized as a sharp tool for the high precision structural imaging of the potential data.

The mantle rocks from Kadaboura and Madara areas represent sections of dismembered ophiolitic complexes developed during the Neoproterozoic in the Eastern Desert of Egypt, which is located in the northwestern corner of the Arabian--Nubian Shield. The Kadaboura mantle rocks comprise serpentinites and serpentinized dunites, whereas those of the Madara consist of serpentinites and serpentinized pyroxenites. Despite the serpentinization of the studied mantle rocks, few relicts of primary chromite, olivine and pyroxene are preserved. Chromite is partly altered having unaltered Al-rich chromite cores surrounded by Fe-rich chromite and Cr-rich magnetite rims. The unaltered Al-rich chromite cores show compositions equilibrated at temperatures mostly below ~500-600°C, which is a temperature comparable to that estimated for primary chromite in greenschist up to lower amphibolite facies rocks. The high Cr# [100xCr/(Cr+Al)= 47-76] of the unaltered chromite cores and the Mg-rich nature of the olivine relicts (Fo91-94) indicate that the studied mantle rocks were produced from a highly depleted mantle that experienced high degrees of melt extraction (mostly ~30-40%). This range of melt extraction resembles that estimated for supra-subduction zone peridotites, but higher than that in abyssal and passive margin peridotites. Furthermore, the clinopyroxene relicts show compositions comparable to those from the Mariana forearc peridotites. Bulk-rock geochemistry also reflects derivation from an extremely depleted and a highly refractory mantle source. Modeling of rare-earth elements suggests that the studied mantle rocks were possibly formed by the interaction of their highly depleted harzburgitic mantle precursors with subduction-related melts/fluids during their evolution in a fore-arc basin of the supra-subduction zone. The proposed geodynamic model suggests that the oceanic lithosphere generated during the seafloor spreading of the Mozambique Ocean was emplaced in the upper plate of the intra-oceanic subduction zone, in which the formely depleted Neoproterozoic mantle of the Arabian-Nubian Shield experienced mature phases of hydrous melting, extreme depletion and enrichment. [ABSTRACT FROM AUTHOR]

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The transition zone between the North and the Central Eastern Desert of Egypt has been investigated using airborne magnetic and radiometric data to better characterize the subsurface structures, the tectonic framework, and mineral occurrences in the area. The magnetic data were subjected to several filtering and depth estimation techniques including edge detectors, Euler deconvolution, 2D forward modeling and 3D inversion. Statistical trend analysis of the lineaments obtained from geological and filtered magnetic maps shows that the major tectonic trends are NNE–SSW, NE–SW, and NW–SE, in addition to less predominant ENE–WSW and N–S trends. Two parallel shear zones trending NE–SW were detected. The causative magnetic structures were imaged at depths varying from the surface down to 2200 m. A number of strong uranium anomalies associated with Younger Granites and Dakhla, Duwi, and Quseir formations were identified which are worth being considered for further ground investigations. [ABSTRACT FROM AUTHOR]

Through various scales of observation, ranging from remote sensing data, field investigations, hand specimens, microscopic petrographic examinations, XRD, to SEM, indicators of various mineralization types are highlighted in Ras El-kharit-wadi Khashir (Eastern Desert, Egypt). Systematic remote sensing exploration of the mineralized zones is performed through integrating Sentinel 2 and ASTER datasets. False-color combinations, informative band ratios, relative absorption band depth, and CEM techniques were applied to discriminate rock units and various types of hydrothermal alterations. Moreover, ALOS PALSAR DEM was utilized to decipher the structural lineaments. Intensive field investigations confirmed hydrothermally altered zones that were picked out through remote sensing analysis and revealed that the study area is affected by cataclastic metamorphism to some extent. Magmatic and metamorphic rock types are represented by propylitic, phyllic, argillic, and silicification zones. Sericitization, chloritization, epidotization, kaolinitization, carbonatization, and silicification are recorded utilizing petrographic and remote sensing investigations. Moreover, the current study reveals that the detected alteration is the main reason for the apparent wide range of petrographic characteristics of each rock type and bearing several opaque minerals, such as pyrite, magnetite, titanomagnetite, chalcopyrite, arsenopyrite, covellite, galena, goethite, and hematite. Most of these opaques were identified using ore microscopy, XRD, and SEM. The distribution of hydrothermal alterations, representative samples bearing mineralization, structurally dissected zones are integrated to build a mineral potentiality map of the study area. The resultant MPM was confirmed via field survey and emphasized the usefulness of the current integrated approach besides highlighting about 125 km2 as potential mineralized zones. [ABSTRACT FROM AUTHOR]

The knowledge of the natural radioactivity content of various radionuclides in the rocks plays an important role in the health physics because of the population's exposure to the radiation. The study is devoted to assessing the specific activity and examining the radiation hazard indices of naturally occurring radionuclides 226Ra, 232Th, and 40K in rocks samples at different locations in Gabal Qatar II, Eastern Desert, Egypt. The activities were measured using a γ-ray spectrometer with a hyperpure germanium detector (HPGe). They ranged from 279 ± 50 to 196061 ± 19726, from 48 ± 13 to 23223 ± 2342, and from 17 ± 2 to 1358 ± 216 Bq kg–1 for 226Ra, 232Th, and 40K, respectively. The calculated hazard indices due to natural radionuclides were higher than the average national and world recommended values; therefore, the rocks pose health risks to the population of the area. [ABSTRACT FROM AUTHOR]

Egypt is characterized by many deserts associated with cities. The desert raven is considered an ancient one of the most abundant birds in the Egyptian desert and is susceptible to a wide range of ectoparasites. therefore, the present study was to identify the ectoparasites that infect brown-necked raven Corvus ruficollis in Wadi Dara, Eastern Desert, Red Sea Governorate, Egypt. During the two years from 2020 to 2022, several parasites were collected from a brown-necked raven. Sixteen live brown-necked ravens and nine nests in the Red Sea governorate were investigated. The collected ectoparasites were thirteen lice species belonging to two suborders, four dipteran species belonging to two families, ten mite species belonging to two families, also nine tick species belonging to two families. Generally, ectoparasites are considered the primary cause of many dangerous effects for many domestic and migratory bird species, the presence of the brown-necked ravens in the bird migration route in the eastern desert increases the chance of ectoparasites transmission between different species in the same area. [ABSTRACT FROM AUTHOR]

Granite rocks are currently one of the foremost raw materials that can be used for various economic purposes such as ornamentation and building materials, because they do not possess radioactive concentrations and have good physical and mechanical properties. The granite rocks of north Um Taghir are connected to neoproterozoic rocks and integrated to the north Arabian-Nubian Shield (ANS), which lies in Northeast Africa. Inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence analysis, concurrent to some statistical analysis, have been carried for major oxides and some trace elements to extract much fundamental information by following certain mathematical methods. The exposed granite rock units in north Um Taghir are classified into four rock units represented by tonalite, granodiorite, monzogranite, and alkali-feldspar granite which are cut by different types of dikes. The magma of tonalite and granodiorite is low-to-medium K calc-alkaline affinity, while the magma of monzogranite and alkali-feldspar granite is medium-to-high K calc-alkaline affinity, and of metaluminous to peraluminous nature. Granite rocks show a slightly depletion of fractionated patterns from light rare earth elements (LREEs) to heavy rare earth elements (HREEs) with slightly positive to negative Eu anomalies from tonalite to monzogranite and alkali-feldspar granites. The statistical criteria have been achieved to explore the significant differences of radiological hazard parameters among samples. It is obvious that there is no homogeneity among samples; furthermore, in Kruskal–Wallis test, Mann–Whitney test, and Pearson correlation coefficient, it can be noticed that there are significant differences between each pair of samples: tonalite, monzogranite; tonalite, alkali-feldspar granite; granodiorite, monzogranite; and granodiorite, alkali-feldspar granite. There is a strong direct relationship among granodiorite and both tonalite and alkali-feldspar granite, and among alkali-feldspar granite and tonalite and granodiorite. There is a strong inverse relationship among monzogranite and tonalite, granodiorite, and alkali-feldspar granite. As stated by all results, it can be mentioned that the granite rocks have a worthy result of mechanical and physical properties. So that they can be used for various economic purposes.

The Khashir gabbro-granitoid suite represents a bimodal intrusive complex exposed in the northern part of the Arabian-Nubian accretionary orogen. The gabbro is composed mainly of amphibole and plagioclase, while the granitoid is represented by tonalite. The gabbro and tonalite yielded overlapped SIMS U-Pb zircon ages of 736 ± 5 and 727 ± 5 Ma, respectively. The gabbro occurs as dikes with some ultramafic screens, but it appears massive close to the granitoid. The gabbro forms lobate enclaves in its contact with the tonalite. Both the gabbro and the tonalite follow the medium-K magmatic series and exhibit arc-like geochemical signatures. The gabbro was probably generated by partial melting of subduction-modified N-MORB-like mantle related to oceanic arc rifting. The geochemical characteristics of the tonalite are consistent with low-pressure anhydrous melting of a mafic source. The tonalite and the widespread surrounding granitoids are similar to the Izu-Bonin arc middle crust. The regional geochemical variation in the K 2 O contents and La/Yb ratio within the batholitic belt suggests that the oceanic arc was built above an east/northeast-dipping subducted slab. The lack of the plume-related magmatism and the juvenile nature of the arc material, as indicated by the zircon εHf(T) values (+ 9.5 to + 14.8) of the Khashir suite, related the construction of such Tonian oceanic arc to the subduction at the periphery of Rodinia rather than to the internal rifting and breakup of the Rodinia supercontinent during the formation of the Arabian-Nubian accretionary orogen. • The Khashir complex is composed mainly of amphibole-rich gabbro and tonalite. • The gabbro and tonalite yielded zircon ages of 736 ± 5 and 727 ± 5 Ma, respectively. • Geochemistry is consistent with a rifted to rear intra-oceanic arc settings. • The Arabian-Nubian Shield was formed by subduction rather than by plume activities. [ABSTRACT FROM AUTHOR]

Band rationing, principal component analysis (PCA) and decorrelation stretch (DS) techniques of Landsat-8 with Sentinel-2 data successfully used in the discrimination of the lithological units and the surface structure features of Wadi Al-Miyah area in the Central Eastern Desert of Egypt. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) were processed to identify the hydrothermal mineralized alteration zones related to the radioactive minerals. Airborne gamma-ray spectrometry (AGRS) has been used to determine the naturally occurring radioactive anomalous zones such as potassium (K), equivalent uranium (eU) and equivalent thorium (eTh) and to follow their spatial distribution in Wadi Al-Miyah area. The analysis of AGRS data revealed that, the study area owns a wide range of radioelement concentrations ranging from 15.5 to 98.4 μR/h, 5.9–37.1 ppm, 17.2–95.4 ppm, and 0.53%-10.29% of total count (TC), (eU), (eTh), and (K), respectively. The interpretation of the Radioelements Composite Image (RCI) successfully delineated the enrichment zones with radioelement concentrations within the alkali feldspar granite, biotite-muscovite schist, granodiorite and the hydrothermal alteration areas within the diorite of Gabal Al- Bakriyah. The results concluded that the integrated remote sensing and airborne AGRS data are promising in detecting the potential areas enriched with K, eU and eTh.

The current study is mainly devoted to the integration, analysis, and interpretation of the available geologic, remote sensing, and potential field data (mainly magnetic) to delineate the subsurface geologic structural elements controlling the western part of Baranes, South Eastern Desert, Egypt, and its relation to the southwestern desert structural regime. Additionally, to detect potential mineralization zones for future mining plans in the study area. The Western part of Baranes has not had enough geomorphological mapping, consequently, potential discoveries of mineralization zones are very low. So, in this paper, an attempt is initiated to better understand the evolution of the geomorphology and structural regime of the region and construct a digital geological map and structural patterns showing the possible locations of mineralization zones based on the previous knowledge from similar potential sites and focus on the future economic importance of the region. To achieve this purpose, processed Landsat-8 images successfully revealed the lithological contacts and fault zones helping in distinguishing between the different rock units; moreover, the aeromagnetic data available in the area is used and several filters are applied including reduction to the pole, Euler homogeneity equation, analytic Signal (AS), and advanced grid filtering are sequentially used aiming to detect the possible subsurface distribution of mineralization zones from the integrated interpretation of magnetic susceptibilities and available geologic and remote sensing data. [ABSTRACT FROM AUTHOR]

Every day, mining corporations grow and develop over Egypt's Eastern Desert in search of gold, silver, and other metals. Mineral resources in Egypt are a powerful tool for increasing national income. In this study, we are interested in mineral exploration, such as gold and porphyry deposits, using aeromagnetic data, applying various processing techniques such as First Vertical Derivative, Total Horizontal Gradient, Analytical Signal, Tilt Derivative, and the center of exploration targeting (CET). The study area is located at the Central Eastern Desert, which includes the Barramiya, Abu Marwa, and Abu Mireiwah regions. The analysis of the delineated structural trends shows that the N–S, NW–SE, and NE–SW are the most effective directions for managing deposits in the investigated area. A minor trend is also shown in the E–W direction and corresponds to the alteration zones reported by geology and prior investigations. Mineralization zones occur most frequently at the contact between ophiolitic serpentinite, sediments, and other rock types. This study intends to add more about the use of the recently developed technology of CET grid analysis for mineral exploration and structural interpretation across the Central Eastern Desert. The CET porphyry analysis map shows locations where several occurrences of porphyry deposits are probable. The newly discovered spots are similar to the area's usual deposit sites. This study proves that aeromagnetic data are significant in mineral exploration since they are useful for the discovery of the structure and shear zones controlling the mineralization zones. [ABSTRACT FROM AUTHOR]