الفهرس 
GENERAL ASPECTS OF THE STUDY AREAOnly 14 pages are availabe for public view
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Abstract
Processing and analysis geophysical data and satellite images have widely used for geological mapping and mineral exploration in arid regions and their abilities increase with the advanced satellite missions of higher spatial, spectral, radiometric and temporal resolutions. The major target of this research is exploration of radioactive materials which achieved by one direct method that represents to radiometric analysis and two indirect methods that represent to satellite images and aeromagnetic analysis.
The present study area is located in upper central Eastern Desert between latitude 26° 21¢ 22’’ to 26° 36¢ 02’’ N and longitude 33° 39¢ 22’’ to 33° 57¢ 58’’ E. The area is about 857 km2 south west of port safaga. The compiled geologic map clarifying the geologic rock units which varying from Pre-Cambrian basement rocks to the Quaternary deposits. The basement complex rocks (granitic, metavolcanic, dokhan volcanic and gabbroic rocks) form the most widespread rock types (about 70 % of the total area) and the other parts included Quaternary, Tertiary and Cretaceous deposits in north, east, central and south of the study area. The geochemical examinations show metasomatism process associated radioactive and rare earth elements bearing minerals represented by; Accessory minerals such as Allanite, Romanechite, Fergusonite, Apatite, Zircon, Monazite and Xenotime (Phosphate mineral) that bearing radioactive materials; Secondary minerals which represented by; Epidote, Zeolites, Chlorite, Sericite and Kasolite that considered one of Uranium minerals associated with black shale, Chert and meta andesite; Base metal concentration represented by (Pb, Zn, Cu, Ni, W, Mn).
Surface lineaments results show that there are two main trends that are NW-SE and NNW-SSE as major trends, this is besides the lineament density, which represents the pathways of the mineralizing solutions. The drainage basins of the study area shown three major drainage basins which have been extracted using the model are from north to south wadi Safaga, wadi Gasus and wadi Quieh. By using remote sensing and GIS techniques, morphometric parameters of drainage basin are calculated.
The statistical analysis of airborne gamma-ray spectrometry data showed that Phosphate and black shale have the highest radioactivity in the study area which reached to 116 &117 ppm in Mohamed rabah and um al huweitat respectively. According to the radiometric signature, the rock unit divided into more than one, hence constructing lithological mapping. Calculation of heat production shown that the highest values are obtained for upper cretaceous rocks (4.58 μWm-3). Satellite images (ASTER & Landsat-8) processing techniques success in mapping both rock units and alteration end members using mapping methods, such as False Color Composites (FCC), Spectral Angle Mapper (SAM), Support Vector Machine (SVM), Band Ratio Codes (BRC), Minimum Noise Fraction (MNF), Feature Oriented Principal Component selection (FPCS), Constrained Energy Minimization (CEM).
Aeromagnetic data is subjected to Gaussian filtering for depth slices and determine regional and residual components at frequency cut off 0.1 km/wavenumber on which two main average levels (interfaces) at depth 1.3 km and 0.7 km for the deep seated and near surface magnetic components respectively. 3D Euler deconvolution and analytical signal techniques are applied to calculate the depth to the magnetic contacts; the results show that, the shallow solutions are related to the outcrops less than 150 m from flight level, and the solutions which related to sedimentary covers locations (Um al-Huweitat, Wasif, and Mohamed Rabah basins) are ranged between 200 to more than 1000 m.
Moreover, anomaly enhancement techniques such as Tilt Derivative (TD), Horizontal Tilt Derivative (TDX) and Source Edge Detect (SED) are applied to enhance shallow features and determining structure element boundary for both shallow and deep seated anomalies. The analysis show the study area is affected with network of dip slip faults due to high shearing and compression stress which formed grabens and horsts at different depths levels in the study area. The trends of predominant faults related to deep seated structures are NW-SE and regard to the shallow seated structure, the predominant fault trends are NW-SE, NNW-SSE, and NNE-SSW. The outcome of 2D forward modeling shown that Mohamed Rabah basin extend to depth ranged between 300 to 350 m, Um al Huweitat basin extend from 100 to 750 m, and in Wasif basin ranged between 150 to 500 m.
Integration of three methods shows good relation between radioactive potentialities and alteration zones and aeromagnetic signatures. Based on these criteria, the present study suggests approximate new exploration sites for radioactive mineral exploration.