الفهرس 
X-ray diffraction analysisOnly 14 pages are availabe for public view
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Abstract
This thesis is concerned with the study of sedimentological, geomorphological and hydrogeological characteristics of Wadi Araba, Wadi Gharib, Wadi Safaga and Wadi Ambagi, along the Red Sea coast. It also focuses on the structural significance of faults, drainage lineations, meteorological and morphometric parameters of drainage basins of both Safaga and Quseir areas in a trial to assess flash floods and mitigate their dangerous effects. The Quaternary sediments of the four wadis consist mainly of siliciclastic detritus in the form of sands, muds and gravels mixed in variable proportions. The sediments generally decrease in size and increase in sorting downstream. The greater part of the deposits is transported by rolling and their grain- size characteristics are indicative of areas of intensive erosion and high energy environments. The majority of the deposits at Wadi Araba is derived from the uplifted two Galalas, whereas at Wadi Gharib, Wadi Safaga and Wadi Ambagi, they are drived from the tectonically uplifted Precambrian rocks and transported by eolian and fluvial processes during periods of wetting and drying. Structural analyses of aerial photographs indicate that, the significant preferred orientations of both faults and drainage lineations at Safaga and Quseir areas are conformable and dominate in the NNW and WNW trends, in addition to NNE trend recognized from drainage lineations. All these trends are determined by poisson frequency distribution at the 99% and 95% probability levels. The analysis of morphometric parameters at Safaga area points out to the existence of 8 hydrographic subbasins of different sizes . In the Quseir area, 2 hydrographic subbasins are present which are characterized by high bifurcation ratio and drainage frequency values, that permit collection of runoff water and possible dangerous flash floods. This demands building earth dams at different localities of the main channels to minimize damages due to flash floods, and to maximize the recharge of the basement aquifers which increase the downward infiltration to obtain more water for different purposes.