INFLUENCE OF STRUCTURES ON DRAINAGE PATTERNS IN THE TUSHKA REGION, SW EGYPT

Since 1997, plans for the agricultural development of the Tushka region in SW Egypt have been underway. In this research, we analyze the area between 22-23°N and 30°30'-31°30'E (the southern Tushka region) that is known to be underlain by 3 aquifers, including the Nubian, distinguishable by their depths: shallow, intermediate and deep. The methods used are cost effective, nondestructive and noninvasive whereby areas with enhanced groundwater resources are located using advanced remote sensing, GIS and geophysical techniques to obtain an improved understanding of the groundwater aquifers there. Radar and thermal images were analyzed to understand the spatial organization of near-surface fluvial and structural features and the results entered into a GIS database. The SRTM DEM was processed to derive hydro-morphological parameters and hydrological properties for drainage basins that were automatically defined. Based on these analyses, specific areas were selected for fieldwork. In these areas, advanced GPR and electrical geophysical profiling was performed in order to provide information about the aquifer depth and the subsurface distribution of faults. So far, three fieldtrips have been conducted. Analysis of ground penetrating radar profiles and their correlation to structures mapped using remote sensing data show positive relations for those areas with faults and fracture zones, and for those without. Analysis of the Vertical Electrical Sounding (VES) data is underway to determine information about the aquifer depth and distribution. In addition, some petrophysical and petrographical measurements are being performed in the lab to understand the best horizons for groundwater accumulation. On completion of this work, the most suitable locations for groundwater accumulation can be depicted with the view that development of these areas will improve the chances of a more sustainable development. Further, understanding the structural setting and the potential distribution of faults that receive most recharge is significant in building development. Faults with increased pore fluid pressure have increased seismic vulnerability and must be flagged in building development plans.