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Acta Geologica Sinica(English Edition) 2014年第1期88卷 196-212页

作者： mohamed abdallah gad darwish Geology Department Faculty of Science Aswan University

The SEM-EDX technique was applied to investigate Au, and Cu＋Sn alloyed grains in the mineralization of the Um Shashoba mine for achieving further understanding of occurrences, internal structures and microchemistry of Au and Cu alloys and associated minerals, and mineralization type. This study is aiming at the genetic history of ore-bearing fluid events, geochemical evaluation and exploration significance. The results showed that the mineralization could be considered as a single major episode generated by metamorphic mesothermal solution rich in sulfides and unsaturated respect to Au. It was differentiated into many stages; started with formation of auriferous pyrite that was pseudomorphed by secondary hematite, limonite and goethite. Three phases of Au alloy were precipitated, and Cu＋Sn and Ag-rich alloys were produced respectively and followed by deposition of two generations of barren pyrite. Calcite and ankerite were crystalized, surrounded and partially replaced some of early formed minerals. Finally, barren muscovite recrystallized around and inside both later formed carbonate minerals that were free of any sign of Au in their structures. The processes of deformation, recrystallization, annealing, dissolution, remobilization and re-precipitation played the most important roles in the genetic history of the mineralization.

关键词： SEM–EDX analyses Au and Cu alloy grains Um Shashoba gold mine Egypt

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Geochemical Stream Sediment Survey in the Wadi Umm Rilan Area,South Eastern Desert,Egypt:A New Occurrence for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1041-1062页

作者： mohamed abdallah gad darwish Geology Department Faculty of ScienceAswan University

The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements.

关键词： geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southEastern Desert Egypt

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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 *** results were examined using statistical,graphical and mapping *** 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 *** is remarkably a close association of Au with Hg and Sb;both are useful as pathfinder elements for Au *** 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 *** 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,***,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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Geochemistry of the High Dam Lake sediments,south Egypt:implications for environmental significance

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International Journal of Sediment Research 2013年第4期28卷 544-559页

作者： mohamed abdallah gad darwish Geology department Faculty of ScienceAswan University

The goal of the present work is to perform a geochemical assessment of High Dam Lake bottom sediments for determining the fate,dispersion and levels of trace elements causing environmental pollution,and provided an access to their probable *** sediment samples were analyzed using ICP-MS for 20 elements;Ag,Ba,Cr,Cu,Ga,Hf,Mn,Pb,Rb,Sc,Sc,Sn,Sr,Ta Th Ti,T1,U,V and Zr,and their obtained data were treated using statistical,graphical and mapping *** results showed the data set of all analyzed elements affected by outliers and extreme values that caused deviation away from *** Wallis test revealed that median of some trace clement levels in Lake sediments,was not significantly different and other elements rejected the Null *** analyzed elements had high values of median and mean in sediments of Lake Nubia rather than Lake Nasser and their normalization gave the same results of calculated environment ***,Lake Nubia sediments possessed high combined EF levels of Th,Sc,Sn,Ag,Zr,Hf,Ta,Sr,U,Ti,V,Cr,and Mn,causing significant contamination,which was great potentially related to industrial,agricultural,urbanization and mining ***,combined EF of Se,Cu,Ga,Pb,Ba,Rb,and Tl,which are highly elevated in southern Lake Nasser sediments owing to their source are great possibly derived from Lake Nubia and geogenic *** decreasing distance towards the High Dam body,the contaminant elements were diminished due to reduction in the environmental factors and Sudanese pollution sources leading to the northern Lake Nasser considered to be less ***,the present study is an environmental alert for contaminated sediments that carried contaminants and considered the secondary source of pollution impact on ecosystem,and subsequently,their environmental risk on Human health.

关键词： Geochemistry High Dam Lake sediments Environmental significance South Egypt

Molecular detection of monocyte chemotactic protein-1 polymorphism in spontaneous bacterial peritonitis patients

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World Journal of Gastroenterology 2014年第33期20卷 11793-11799页

作者： Maysa Kamal Salama Dina Sabry mohamed AS Al-Ghussein Rasha Ahmed Sayed abdallah Fatma mohamed Taha Wael Fathy Miriam Safwat Wadie Mona Nabih Amr Abul-Fotouh Tarneem darwish Medical Biochemistry and Molecular Biology Department Faculty of Medicine Cairo University Cairo11562 Egypt Biochemistry Department Faculty of Pharmacy Al-Azhar University Gaza 1277 Palestine Tropical Medicine Department Faculty of Medicine Cairo University Cairo11562 Egypt Internal Medicine Department Faculty of Medicine Cairo University Cairo 11562 Egypt Tropical Medicine Department Faculty of Medicine Bny Swif University Bny Swif 62511 Egypt Biomedical Informatics and Biostatistics Department Faculty of Medicine Cairo University Cairo 11562 Egypt

AIM: To investigate the association of the functional monocyte chemotactic protein-1 (MCP-1) promoter polymorphism (A-2518G) with spontaneous bacterial peritonitis (SBP).

关键词： Monocyte chemotactic protein-1 Genotype Spontaneous bacterial peritonitis Liver cirrhosis As-cites Gene expression Interleukin-10