ROLE OF REGIONAL STRUCTURES ON SURFACE AND SUBSURFACE WATER FLOW IN EASTERN QATTARA DEPRESSION, WESTERN DESERT, EGYPT
In this study remote sensing data were used to identify buried fluvial channels and fractures\faults. Most of the surface fractures\faults of the study area trend NE-SW and NW-SE directions. GPR surveys were conducted to confirm presence of these channels. The migrated 2D GPR profiles together with field observations identified a major paleochannel distributary system with numerous minor channels at its margins. Potential field data were used to probe deeper subsurface. Magnetic data recognize two aquifer systems; deeper saline-water-bearing (Mesozoic-Paleozoic Nubian sandstone) and shallow fresh-water-bearing (Lower Miocene Moghra sandstone) aquifer systems. Both these aquifer systems are controlled by regional structures. Results of gravity data demonstrate presence of shallow faults and density interfaces in the sedimentary cover overlying the basement rocks. The trend of these shallow structures (faults) agrees with the flow direction of the paleochannel system identified. This work contributes to the reconstruction of paleo drainage of this region and raises a possibility that tectonics may have contribution to the surface and subsurface water flow in eastern Qattara Depression.