الفهرس 
Chapter I Chapter I Page 1 IntroductionOnly 14 pages are availabe for public view
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Abstract
Processing and analysis of 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.
West Ras Gharib area is located in the Northern part of the Eastern Desert. It is enclosed between latitudes 28° 00` to 28° 41` N and longitudes 32° 20` to 33° 00` E and occupies an area approximately 2319.286 Km2. Geologically the mapped area is covered mainly by Precambrian basement rocks, which are unconformably overlain by Phanerozoic sedimentary
succession, while the structural settings delineate that the main trend of the surface lineaments mainly related to NW-SE, NE-SW and NNW-SSE directions.
The remote sensing imagery data Landsat-8 and ASTER bands are used in an integration with the aerospectrometric and aeromagnetic data to delineate the surface uranium provinces in addition to their probable extensions within subsurface.
The current study aims essentially to find a relationship between land surface heat temperature (LST) (derived from the ASTER-TIR data and Landsat 8-TIR) and radiogenic heat production rate (RHPR) (derived from the airborne gamma ray spectrometry) to locate hydrothermal alteration areas and radioactive mineralized zones. In addition to extraction of surface lineaments (from Geological, ALOSPALSAR, SRTM and ASTER GDEM) and comparing them with subsurface lineaments extracted from aeromagnetic data. Reliable results would solve the problem of cost and time besides enabling the design of effective sampling plan for any further geological studies.
Air-borne gamma-ray spectrometry data shows a relative higher RHPR threshold value reached 4.8μW/m3. Besides, ASTER-TIR land surface heat temperature (AST-LST) ranges between 27.64o C to 47.2o C while, Landsat- 8 (LS-8-LST) ranges between 30.64o C to 50.68o C. Comparing all results,
there were a weak relationship or to some extent parallel relation (which mean, when the value of the Y-axis is constant, there are multiple values on X-axis) between RHPR and LST. This is because of the very weak RHPR that is not enough to affect the surface heat temperature, which can be remotely sensed by ASTER and Landsat-8 satellites TIR data. This factor in addition to other factors such as: topography, wind, shading and scattering, rock moisture and density, can strongly affect the surface temperature.
The factor analysis technique is used to derive the ILRU map using the ternary color composite image from the derived three factors F1, F2 and F3, the provided ILRU map enhanced and modified using the statistical signatures of different lithological units obtained from the compiled geological map.
The statistical analysis of airborne gamma-ray spectrometric data shows that there are ten main groups of statistically significant (anomalous) zones have been distinguished and shows localities that represent uraniferous anomalous zones which could be considered as possible target of interest for ground follow-up investigation.
Aeromagnetic data reduced to the north magnetic pole (RTP), is subjected to band-pass filtering for depth slices and determine regional and residual components at depths 2000 m and 800 m for the deep seated and near surface aeromagnetic components respectively. 3D Euler deconvolution, source parameter imaging (SPI) and analytical signal (AS) techniques are applied to calculate the depths to the regional and residual data and through the three techniques those applied, the depths range from 500 to 3000 meters for
regional aeromagnetic component and from 200 to 1000 meters for residual aeromagnetic component. These depth results are agreeing with the residual and regional depths extracted from the magnetic power spectrum of the RTP map as 800 m and 2000 m respectively.
The detection of surface lineaments extracted from remote sensing (ASTERGDEM, SRTM and ALOSPALSAR data) and geological map, in addition to subsurface lineaments extracted from aeromagnetic data (regional and residual magnetic structure anomalies) show that the major trends are NW-SE, NE-SW, WNW-ESE, E-W and N-S.
Satellite images (ASTER & Landsat-8) processing techniques success in determine the hydrothermal alteration zones using mapping methods, such as false color composites (FCC), band ratio (BR), principle component analysis (PCA), feature oriented principal component selection (FPCS), and minimum noise fraction (MNF).
By integrating the results, it was found that there is tie relationship between the extracted fault trends, six radioactive zones, location of uraniferous zone concentration, radiogenic heat production rate and hydrothermal alteration zones.