الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Haliab area, south eastern desert, Egypt. It must be doing detailed image processing for study area to delineate the alteration zones and differentiated between rock types, The studied area is located about 25 km west of Abu Ramad City on the coastal highway that is roughly bound by latitudes 22º 17` - 22º 21` N and longitudes 36 ° 10` - 36° 17` E. One of the high favorable areas are Gabal El Sela and south part of Qash Amir pluton is high radioactivity, Gabal El Sela area was subjected to detailed field geology and mapping. This research aims at integrating remote sensing data and field studies to prospect for radioactive materials at the study area, South Eastern Desert of Egypt. This area is a part of the Arabo - Nubian shield, which is constituted by Late Precambrian basement rocks and developed during the Pan African tectono-thermal event. Geological interpretation of Landsat ETM+ image and field studies revealed that the study area is mainly covered by ophiolitic ultramafic rocks, intermediate metavolocanics, granodiorites, biotite granites and garnetiferous muscovite granites. These rocks are injected by pegmatitic and quartz veins and cut by acidic and basic dykes. The processed Landsat ETM+ data enables also to identify uraniferous alteration zones hosted in the granitic rocks (using band ratio 5/7, 4/5, 3/1 in RGB, density slicing and supervised classification techniques). The measured reflectance values (DNs) of six spectral bands of Landsat ETM+ for all exposed rock types in the study area show that the alteration zones have the highest reflectance values.The study recorded the presence of uranium mineralizations in alteration zones associating with the granitic rocks occurring along ENE-WSW trending shear zones. Three uranium-bearing alteration zones hosted in granitic rocks were detected. These zones are characterized by ferrugination, silicification, grizenization and kaolinitization. The most promising alteration zones (Site 1) occurs at the northeastern part of Gabal El Sela and is characterized by very high radioactive anomalies (up to 5000 ppm eU). Microprobe analyses of samples collected from these alteration zones reveal the presence of uraninite crystals. It seems that the high fractures density of the granitic rocks acted as good channels for the ascending hydrothermal fluids and the percolating meteoric water, that leached the uranium minerals disseminated all over the rocks and redeposited them along the fractures of the shear zones. This study demonstrates the utility of orbital remote sensing data for finding unknown mineralized zones in the Eastern Desert of Egypt and similar arid regions.The geochemistry and the analyses of the accessory minerals were studied also to characterize the U hosting minerals and their U-fertility. The ENE-WSW shear zone cross cut El Sela granite at the northern boarder was separated as the more anomalous zone in the area. In order to illustrate the geophysical signature of Sela U-mineralization, the radiometric, maps were produced from the detailed ground survey using 400m interval and sometimes close to 40m. Because of the sharp development of radiometric signatures over Gabal El Sela Shear zone, the shear zone is characterized by very high eU anomalies, though the process of uranium mobilization toward the shear zone is very important as such altered rock were subjected to mineralization bearing solutions; shear zone acts as a good trap for U-rich fluids or U- ores. Geochemicaly, El-Sela and Qash Amir younger granites are nearly similar in their geochemical characteristics. Generally, they are low-Ca, S-type granites slightly enriched in alkalies and depleted in Mg. Mineralogical studies revealed the presence of secondary uranium minerals (uranophane and autonite), fluorite, sulphides (pyrite and galena), iron oxides (magnetite and hematite), iron- titanium oxides (ilmenite and rutile), micas, zircon and monazite. Under the binocular microscope, uranophane are distinguished by their canary to lemon yellow colour.