الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Um Junud area has been given little attention, although it represents a key to understand the geologic history of the SED and the entire ED. The present thesis is an integrated study using GIS and remote sensing (ASTER data imegary) and field data to geological mapping and structural analysis. False-color composite image, color-ratio composite image, decorrelation stretch, mafic index (MI) and quartz index (QI) were used to discriminate and map various lithologies. False color images of ASTER band combination (7, 3, 1), with previous lithological mapping studies of the study area, allow preliminary to discriminate the exposed rock units and consequently to draw the base map. The Quartz Index (QI) was high for quartz-rich/feldspar, whereas the mafic index separates the mafic and ultramafic rocks. Spectral Angle Mapper (SAM) supervised classification using reference spectra of USGS spectral library was used for detecting alteration zones. For verification, the accuracy assessment carried out to evaluate the band combination and band ratios that used in lithologic mapping.
The lineaments trends of the study area have been auto-extracted from ASTER band combination 7, 4, 2 in RGB and ASTER global elevation model(GDEM) and calibrated with and ground truth data. The drainage network also extracted automatically from ASTER GDEM and show the prevalence of two main structural trends; NE-SW and NW-SE directions.
Um Junud is a polydeformed area showing a complex history indicated by various structures and fabrics. The three Pan-African deformation phases (D1, D2 & D3) recorded elsewhere in the ED are well represented in the study area. Thrusting and thrust related structures play significant role in the structural shaping of the area. The most obvious thrusts are Abu Jurdi thrust sheets strike E- W to ESE – WNW, Abu Marwah flower structure which extends with NW-SE strike, Gabal Um Junud thrust fault strikes nearly N- S to NNW-SSE. The superposition of D1 folds on pre-D1 folds led to the development of a map-scale mushroom-like interference pattern of folding which is described for the first time in the present study. A new domal-like structure was recognized in the present study, referred as Alhefery gneiss dome. Two sets of shear zones NE-SW, NW-SE developed in the area, the most prominent is Almandeet-Kalalat shear zone(AKSZ) which is a major NE-trending high strain zone extending from Gabal Almandeet in the east to the Gabal Kalalat in the west with dextral sense of shearing.
Quntitative strain analysis using the Rf/φ and Fry methods has been also been done in the present thesis. It is concluded that finite strain is of the same order of magnitude for various lithologic units outcropping in the area, and that contacts were formed under semi-brittle to semi-ductile deformation conditions.
Furthermore. The present study was an attempt to figure out a geo-data management approach by using the geo-information system (GIS). It is proposed to capture different geological data and processed digital images, together with conceptual model, to facilitate a geo-spatial framework and improve the exploration and detection of lithologies, drainage system and other features that would contribute the sustainable development of SED.