الفهرس 
Location of the Study Area
Geological Overview of the Eastern DesertOnly 14 pages are availabe for public view
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Abstract
The examined Gabal Umm Hammad area is located at the central part of the Eastern Desert. It covers an area about 1490.4 km2 and lies between longitudes 33o 50′ 42.20″ and 34o 21′ 15.23″ East and latitudes 25o 54′ 13.03″ and 26o 15′ 27.74″ North. The present work deals essentially with the analysis and interpretation of airborne gamma-ray spectrometry, gravity and aeromagnetic prospecting and digital elevation model shading to delineate the surface spatial extension of radioactive anomalies with relevant dose rates and to explore the relationship between these extensions and the dominating structures, lithologic variations and the tectonic evolution. A Detailed geologic map of the study area which illustrates the distribution of exposed rock units together with the structural trends affecting the area is provided. The stratigraphic colomn of the exposed rocks in the study area is arranged from older to younger as: 1) Late Proterozoic rocks, comprising the Muʹtiq group (classified into orthogneiss and psammilic gneise)., Ophiolite group (consisting mainly of massive serpentine talc carbonate and related rocks), Hammamat clastic (essentially unmetamorphosed conglomerate, greywackes, sandstone, siltstone and mudstone)., Younger granite (represented by calc alkaline of weakly deformed granitic rocks overlain by pink grey coarse and medium grained equigranular biotite monzogranite), Dokhan volcanic; (mostly non metamorphosed volcanics) and Post Hammamat felsite (composed of effusive felsite, felsite porphyry and quartz porphyry and overlain by a series of trachyte plugs and sheets). 2) Cretaceous rocks, comprising from the older to younger the Taref Formation (representing the oldest sedimentary beds) that rests uncomfortably over the basement complex rocks., Quseir Formation (made up of littoral varicolored shale, siltstone and flaggy sandstone) and Duwi Formation (consisting mainly of three phosphate horizons ranging in thickness between 30-100 m and separated by beds of marls, shale and Oyster limestone with flint. 3) Cenozoic Rocks, from the bottom to the top are: Tarawan Formation (made up of marl and marly limestones), Thebes Formation (consists of fossiliferous limestone), Nakhil Formation (composed of very coarse brecciate beds and fine-grained lacustrine deposits), Ranga Formation (made up of conglomerate derived from the basement with rounded to angular and ranged in size from granular to boulders), Umm Mahara Formation (rests unconformably over Ranga Formation and is made up of a lower sandy limestone member and upper gypsiferous fossiliferous limestone member), Abu Dabbab Formation (formed of evaporate (gypsum) deposits and extends for hundreds of kilometres along the coastal plain), Umm Gheig Formation (consists mainly of hard dolomite bed that seems to be deposited in shallow water above the wave base), Shagra Formation (composed of sandstone, bioclastics and some siliciclastics) and Quaternary deposits (comprising raised beaches, wadi gravel deposits, silt, sandy bands and coral reefs). Several structural trends have been recorded at the area under investigation including the; NW-SE (Red Sea - Gulf of Suez trend), NE-SW (Syrian arc trend) and N-S (East African trend).