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Origin and Petrogenetic Implications of Spessartine Garnet in Highly-Fractionated Granite from the Central Eastern Desert of egypt

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Acta Geologica Sinica(English Edition) 2020年第3期94卷 763-776页

作者： Mabrouk SAMI Theodoros NTAFLOS Haroun A.MOHAMED Esam S.FARAHAT Christoph HAUZENBERGER Nasser M.MAHDY Khaled M.ABDELFADIL Douaa FATHY Geology Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt Department of Lithospheric Research University of ViennaAlthanstrasse 14A-1090 ViennaAustria Institute of Mineralogy and Petrology Karl-Franzens UniversityGrazAustria Nuclear Materials Authority P.O.530El-MaadiCairoEgypt Geology Department Faculty of ScienceSohag UniversityEgypt

A highly-fractionated garnet-bearing muscovite granite represents the marginal granitic facies of the Abu-Diab multiphase pluton in the Central Eastern Desert of egypt. New electron microprobe analyses(EMPA) and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) data from garnets are reported, in order to constrain their origin and genesis. Garnet in the Abu-Diab host granite is euhedral to subhedral, generally homogeneous and, in rare cases, it shows weak zonation. The garnet contains appreciable amounts of MnO and FeO, with lesser amounts of MgO and CaO, yielding an end-member formula of Sps61–72Alm25–35Prp1–4Adr0–1. Moreover, it is depleted in large ion lithophile elements(LILE) with lower values of Ba, Nb and Sr relative to the primitive mantle. Additionally, it contains high concentrations of HREE and Y and their REE pattern shows strong negative Eu anomalies. The garnet was crystallized under relatively low temperature(646°C–591°C) and pressure(< 3 kbar) conditions. The textural and chemical features indicate that the garnet is magmatic in origin and is chemically similar to that from highly-fractionated A-type granite. It was probably formed at the expense of biotite in a highly-evolved MnO-rich magma and/or by hydroxyl complexing of Mn during the ascending fluid phases.

关键词： spessartine garnet LA-ICP-MS A-type granite Abu-Diab egypt

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Avian influenza virus surveillance in migratory birds in egypt revealed a novel reassortant H6N2 subtype

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Avian Research 2019年第4期10卷 507-516页

作者： Ali M.Zanaty Ahmed M.Erfan Wessam H.Mady Fatma Amer Ahmed A.Nour Neveen Rabie Mohamed Samy Abdullah A.Selim Wafaa M.M.Hassan Mahmoud M.Naguib National Laboratory for Veterinary Quality Control on Poultry Production Animal Health Research InstituteGiza 12618Egypt Zoonosis Science Centre Department of Medical Biochemistry and MicrobiologyUppsala University75123 UppsalaSweden

Background:Avian influenza viruses(AIVs)have been identified from more than 100 different species of wild birds around the globe.Wild migratory birds can act as potential spreaders for AIVs to domestic birds between different countries.egypt is situated on important migratory flyways for wild birds between different continents.While much is known about circulation of zoonotic potential H5N1 and H9N2 AIVs in domestic poultry in egypt,little is known about the pivotal role of migratory birds in the maintenance and transmission of the viruses in egypt.Methods:Targeted AIV surveillance has been conducted in 2017 in different wetlands areas in Northern and Eastern egypt.Results:AIV of subtype H5 was detected in two bird species.In addition,a novel reassortant strain of the H6N2 subtype was identified which reveals the continuous risk of new influenza virus(es)introduction into egypt.This novel virus possesses a reassortant pattern originating from different AIV gene pools.Conclusions:Intervention control strategies should be performed to minimize the possible contact of domestic birds with wild birds to lower the risk of virus transmission at this interface.In addition,constant monitoring of AIVs in migratory birds is essential in the early detection of influenza virus introduction into egypt.

关键词： Avian in fluenza virus H6N2 egypt Reassortment Wild birds

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Geochemical and Environmental Evaluation of Um Shashoba Gold Mine Area,Southeastern Desert,egypt

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Acta Geologica Sinica(English Edition) 2011年第4期85卷 881-898页

作者： Mohamed Abdallah Gad DARWISH Geology Department Aswan Faculty of ScienceSouth Valley UniversityPost No.81528 AswanEgypt

A suite of elements（Ag,Au,Ba,Bi,Cd,Co,Cr,Cu,Ga,Hf,Hg,Mn,Mo,Ni,Pb,Rb,Sb,Se, Sr,Te and Zn）,total organic carbon（TOC）and pH were analyzed in stream sediment and tailing samples from Um Shashoba area,in order to evaluate Au placer and the sediments being impacted by old mining activities.Analytical results were examined using statistical,graphical and mapping methods.In spite of the results revealing that Au and most of the elements in sediments were in general significantly lower than those in tailing,Au was concentrated in the NE and SW parts forming Au placer.It is remarkably a close association of Au with Hg and Sb;both are useful as pathfinder elements for Au placers.Values of pH could not control a fate of analyzed elements,whereas TOC and Mn oxides and hydroxides could uptake some elements Au,Ba,Co,Cr,Hg,Ni,and Sr.The results also indicated that the sediments were contaminated by anthropogenic factors causing moderate,strong to very strong pollution with respect to Bi,Se and Te,respectively.Additionally,geogenic factors could also contribute elemental enrichment to the drainage system and cause significant toxicity level.

关键词： geochemical exploration environmental evaluation Um Shashoba gold mine egypt

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Geochemical Constraints of the Ediacaran Volcano-Sedimentary Succession of the Sa'al Metamorphic Complex at Wadi Zaghra, South Sinai, egypt

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 50-73页

作者： SAMUEL D.Michael MOUSSA E.Hilmy AZER K.Mokhles SADEK GHABRIAL Doris Geological Sciences Department National Research Centre (NRC)

The volcano-sedimentary succession around Wadi Zaghra in Sinai, at the northernmost segment of the Arabian Nubian Shield, comprises volcanic rocks interbedded with rather immature sediments. The succession is dominated by intermediate to silicic volcanics of medium-to high-K calc-alkaline affinity. It is divided into two units, the lower unit includes intermediate rocks and dacites interbedded with graywackes, semi-pelites and pelites and topped by polymict conglomerates. This unit is subjected to folding and regional metamorphism(up to garnet zone) and is intruded by quartz diorite-granodiorite inducing, locally, low-pressure contact thermal metamorphism. The unmetamorphosed upper unit encompasses acid volcanics intercalated with litharenite, sublitharenite and minor arenite. The rhyolites of this unit pertain to the highly fractionated granites and are characterized by an agpaitic index(NK/A) ranging from 0.87 to 0.96. They may reflect either extensive interaction of subduction-related magmas with the continental crust or a change in the tectonic regime. The present lithological and geochemical characteristics of the studied sediments together with available zircon ages indicate rather distal provenance of their detritus. This detritus comprises fluvial-alluvial sediments accumulated in the intermontane basins, which are half-grabens or tilted fault blocks. The tectonic setting of the depositional basins is active continental margin and continental island arcs. Geochemical patterns of the Zaghra volcano-sedimentary succession indicate their correlation with the Dokhan Volcanics-Hammamat Clastics sequence of the Eastern Desert of egypt. Also, the Zaghra volcanics display geochemical similarities with those exposed in Sinai, at the Rutig, Ferani and Iqna Shar'a areas. The Zaghra succession is dated as Ediacaran but is not related either to the ensimatic island arc assemblage or to the rift-related assemblage formed during the early stages of the break-up of Rodinia as previously thought.

关键词： geochemistry Neoproterozoic Dokhan Volcanics Arabian-Nubian Shield Sinai egypt

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Sequence Stratigraphy and Rudist Facies Development of the Upper Barremian-Lower Cenomanian Platform, Northern Sinai, egypt

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Acta Geologica Sinica(English Edition) 2018年第1期92卷 286-310页

作者： Yasser SALAMA Michael GRAMMER Shaban SABER Soheir EL-SHAZLY Gouda ABDEL-GAWAD Beni-Suef University Faculty of SciencesGeology Department Boone Pickens School of Geology Oklahoma State University

The Lower Cretaceous sections in northern Sinai are composed of the Risan Aneiza(upper Barremian-middle Albian) and the Halal(middle Albian-lower Cenomanian) formations. The facies reflect subtle paleobathymetry from inner to outer ramp facies. The inner ramp facies are peritidal, protected to open marine lagoons, shoals and rudist biostrome facies. The inner ramp facies grade northward into outer ramp deposits. The upper Barremian-lower Cenomanian succession is subdivided into nine depositional sequences correlated with those recognized in the neighbouring Tethyan areas. These sequences are subdivided into 19 medium-scale sequences based on the facies evolution, the recorded hardgrounds and flooding surfaces, interpreted as the result of eustatic sea level changes and local tectonic activities of the early Syrian Arc rifting stage. Each sequence contains a lower retrogradational parasequence set that constituted the transgressive systems tracts and an upper progradational parasequence set that formed the highstand systems tracts. Nine rudist levels are recorded in the upper Barremian through lower Cenomanian succession at Gabal Raghawi. At Gabal Yelleg two rudist levels are found in the Albian. The rudist levels are associated with the highstand systems tract deposits because of the suitability of the trophic conditions in the rudist-dominated ramp.

关键词： Cretaceous sequence stratigraphy rudists Sinai egypt

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Mineralogy and geochemistry of Nb-,Ta-,Sn-,U-,Th-,and Zr-bearing granitic rocks from Abu Rusheid shear zones,South Eastern Desert,egypt

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Chinese Journal Of Geochemistry 2011年第2期30卷 226-247页

作者： Ali M.A. Lentz D.R. Hall D.C. Nuclear Materials Authority P.O.530.El MaadiCairoEgypt Department of Geology New Brunswick UniversityUNBCanada Microscopy and Microanalysis Facility New Brunswick UniversityUNBCanada

Granite-hosted,Nb-,Ta-,Sn-,U-,Th-,and Zr(Hf)-bearing mineralization from the Abu Rusheid shear zones occurs about 97 km southwest of the town of Marsa Alam,South Eastern Desert,egypt.The SSE-trending brittle-ductile Abu Rusheid shear zones crosscut the peralkalic granitic gneisses and cataclastic to mylonitic rocks(mylonite,protomlyonite,and ultramylonite).The northern shear zone varies in width from 1 to 3 m with a strike length of >500 m,and the southern shear zone is 0.5 to 8 m wide and >1 km long.These shear zones locally host less altered lamprophyre and locally sheared granitic aplite-pegmatite dykes.The rare-metal minerals,identified from the peralkalic granitic gneisses and cataclastic to mylonitic rocks are associated with muscovite,chlorite,quartz,fluorite,pyrite,magnetite,and rare biotite that are restricted to the Abu Rusheid shear zones;these are columbite-tantalite and pyrochlore(var.betafite) in the northern shear zone and ferrocolumbite in the southern shear zone.Cassiterite occurs as inclusions in the columbite-tantalite minerals.U-and Th-minerals(uraninite,thorite,uranothorite,ishikawaite,and cheralite) and Hf-rich zircon coexist.Magmatic(?) zircon contains numerous inclusions of rutile,fluorite,U-Th and REE minerals,such as uranothorite,cheralite,monazite,and xenotime.Compositional variations in Ta/(Ta+Nb) and Mn/(Mn+Fe) in columbite range from 0.07-0.42 and 0.04-0.33,respectively,and Hf contents in zircon from 1.92-6.46 of the two mineralized shear zones reflect the extreme degree of magmatic fractionation.Four samples of peralkalic granitic gneisses and cataclastic to mylonitic rocks from the southern shear zone have very low TiO2(0.02 wt%-0.04 wt%),Sr [(15-20)×10-6],and Ba [(47-78)×10-6],with high Fe2O3T(0.94 wt%-1.99 wt%),CaO(0.14 wt%-1.16 wt%),alkalis(9.2 wt%-10.1 wt%),Rb [(369-805)×10-6],Zr [(1033-2261)×10-6],Nb [(371-913)×10-6],U [(51-108)×10-6],Th [(36-110)×10-6],Ta [(38-108)×10-6],Pb [(39-364)×10-6],Zn [(21-424)×10-6],Y [(8-304)×10-6],Hf [(29-157)×10-6],and ∑REE [(64-304)×10-6],especia

关键词： uranium thorium zircon columbite-tantalite fluorite monazite xenotime age dating granitic gneisses South Eastern Desert egypt

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Repeated occurrence of palaeo-wildfires during deposition of the Bahariya Formation(early Cenomanian) of egypt

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Journal of Palaeogeography 2019年第4期8卷 332-345页

作者： Haytham El Atfy Tarek Anan Andre Jasper Dieter Uhl Department of Geology Faculty of ScienceMansoura UniversityMansoura 35516Egypt Programa de Pos-Graduacao em Ambiente e Desenvolvimento PPGADUniversidade do Vale do Taquari UnivatesLajeadoRio Grande do SulBrazil Senckenberg Research Institute and Natural History Museum 60325 Frankfurt am MainGermany Senckenberg Centre for Human Evolution and Palaeoenvironment Tubingen University72076 TubingenGermany

The Upper Cretaceous(early Cenomanian)Bahariya Formation of egypt has an outstanding reputation for its wealth of vertebrate remains,including a variety of iconic dinosaurs,like the carnivorous Spinosaurus and Carcharodontosaurus,as well as the herbivorous Aegyptosaurus and Paralititan.Besides these dinosaur fossils,the Bahariya Formation yielded also a wealth of invertebrate and plant remains,but even today many aspects concerning the continental palaeoenvironments reflected in these deposits(including the occurrence of palaeo-wildfires)have not been studied in detail.So far six distinct macro-charcoal bearing levels could be identified within the type section of the Bahariya Formation at Gabal El Dist profile,one of the most prolific outcrops of this formation in terms of fossil occurrence located in the north of the Bahariya Oasis,Western Desert,egypt.Most of the charcoal investigated by means of SEM originates from ferns,pointing to a considerable proportion of this plant group within the palaeo-ecosystems that experienced fires.Gymnosperms and(putative)angiosperms have less frequently been identified.The collected data present evidence that the landscapes at the northern shores of Gondwana repeatedly experienced palaeo-wildfires,adding extra proof to previous statements that the Late Cretaceous was a fiery world on a global scale.

关键词： Bahariya Oasis Gabal El Dist Charcoal Wildfire Dinosaurs Upper Cretaceous Early Cenomanian egypt

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On the Validity and Evolution of Assilina Species during the Ypresian–Lutetian:Example from Bir Dakhl,Eastern Desert,egypt

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1080-1085页

作者： Safia AL MENOUFY Mohamed BOUKHARY University of Ain Shams Faculty of EducationDepartment of Biological&Geological SciencesCairo 11341Egypt Geology Department University of Ain ShamsFaculty of ScienceCairo 11566Egypt

The genus Assilina is a taxon within the Nummulitacea that appeared early in the Ypresian(Early Eocene)and continued until the end of the Lutetian(Middle Eocene).Thus,this taxon could be useful for the chronostratigraphy of this time interval.Lower Eocene rocks in southern Galala,egypt are exposed at Bir Dakhl.This section includes marl sediments with debris flow shallow-marine facies deposits laid down during early Eocene times and includes fossils of large foraminifera:Assilina placentula Deshayes,1838 and Nummulites burdigalensis de la Harpe,1926.These are systematically treated,described and illustrated.Nummulites burdigalensis belongs to the N.burdigalensis group,and Assilina placentula belongs to the group of Assilina exponens.This assumption is based on qualitative morphology and quantitative measurements.Both species,together with Operculina libyca Schwager,1883,enable the assignment of the Bir Dakhl(D5-40 Section)to the Early Eocene,Ypresian(SBZ10 of Serra-Kiel et al.,1998)supporting an earlier opinion that Assilina placentula belongs to that zone in the calibrated larger foraminiferal biostratigraphic zonation.

关键词： foraminifera Assilina evolution Eocene Galala egypt

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Transpressive Structures in the Ghadir Shear Belt, Eastern Desert, egypt: Evidence for Partitioning of Oblique Convergence in the Arabian-Nubian Shield during Gondwana Agglutination

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1614-1646页

作者： Mohamed ABD EL-WAHED Samir KAMH Mahmoud ASHMAWY Aly SHEBL Geology Department Faculty of Science Tanta University

Transpressional deformation has played an important role in the late Neoproterozoic evolution of the ArabianNubian Shield including the Central Eastern Desert of egypt.The Ghadir Shear Belt is a 35 km-long,NW-oriented brittleductile shear zone that underwent overall sinistral transpression during the Late Neoproterozoic.Within this shear belt,strain is highly partitioned into shortening,oblique,extensional and strike-slip structures at multiple scales.Moreover,strain partitioning is heterogeneous along-strike giving rise to three distinct structural domains.In the East Ghadir and Ambaut shear belts,the strain is pure-shear dominated whereas the narrow sectors parallel to the shear walls in the West Ghadir Shear Zone are simple-shear dominated.These domains are comparable to splay-dominated and thrust-dominated strike-slip shear zones.The kinematic transition along the Ghadir shear belt is consistent with separate strike-slip and thrustsense shear zones.The earlier fabric(S1),is locally recognized in low strain areas and SW-ward thrusts.S2 is associated with a shallowly plunging stretching lineation(L2),and defines^NW-SE major upright macroscopic folds in the East Ghadir shear belt.F2 folds are superimposed by^NNW–SSE tight-minor and major F3 folds that are kinematically compatible with sinistral transpressional deformation along the West Ghadir Shear Zone and may represent strain partitioning during deformation.F2 and F3 folds are superimposed by ENE–WSW gentle F4 folds in the Ambaut shear belt.The sub-parallelism of F3 and F4 fold axes with the shear zones may have resulted from strain partitioning associated with simple shear deformation along narrow mylonite zones and pure shear-dominant deformation in fold zones.Dextral ENEstriking shear zones were subsequently active at ca.595 Ma,coeval with sinistral shearing along NW-to NNW-striking shear zones.The occurrence of upright folds and folds with vertical axes suggests that transpression plays a significant role in the tectonic evolution of the Ghadir shear belt

关键词： Arabian-Nubian Shield Ghadir shear belt transpression splay-dominated and thrust-dominated strike-slip shear zones egypt

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Urological and genital surgery in ancient egypt

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History & Philosophy of Medicine 2023年第1期5卷 16-23页

作者： Patric Blomstedt Department of Clinical Neuroscience UmeåUniversityUmeåSE-90185Sweden

Background:Ancient egypt might be considered the cradle of medicine.The modern literature is somewhat too enthusiastic regarding the procedures given an egyptian origin.The aim of the current paper is to briefly analyze the claims regarding urological and genital surgery in egypt,in order to decide what the egyptian actually do,and what has incorrectly been ascribed to them.Methods:The original sources as well as the modern literature was reviewed regarding surgery in ancient egypt.Results:There is only one source indicating a urological procedure for medical indications in the egyptian material.The Ebers papyrus can be interpreted as describing a surgical treatment for hydrocele.The sources are more abundant regarding male circumcision,while female circumcision is mainly documented from a later period.The suggestions that castration and lithotomy were performed are based on a lack of understanding of the sources.Conclusion:The ancient egyptians did possibly treat hydrocele with a minor surgical procedure,but there are no indications in the sources that other urological procedures were performed.Circumcisions were common,but were not performed on a medical indication.These findings are in line with the general level of egyptian surgery.

关键词： egypt urology circumcision castration history

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