الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
At the present time, there is an increasing need for finding new fresh water resource worldwide, especially in the aired regions. Therefore, finding new freshwater resources is even more pressing and is more urgent in all over the world including Egypt, which gets almost all of its fresh water from the River Nile. The Kharga Oasis represents one of the most promising areas, on which the government relies for development and land reclamation. The Nubian Sandstone Aquifer (NSA) beneath the Kharga Depression is considered replenish able artesian system with enough ground water that can last for more than century. Therefore the Kharga Depression is selected for this study because it is a suitable site for development using the Nubian Sandstone Aquifer (NSA) ground water.
The present study represents an application of 2D homogeneous function method to investigate the subsurface geologic sections and evaluating the groundwater potentiality in two selected regions within the Kharga Oasis territory. The first region occupies the Northwestern part of the Kharga town where the thickness of the NSA is more than 600m and the second region represents the southern part of the Kharga Oasis (south of Bares town) where the thickness of the NSA is ranged between zero, where the basements complex is crop out to the surface, and 400m maximum. The study focused on understanding the structural complexity of the Kharga Depression and the inter play between groundwater movement and brittle structure.
A simple inversion of refraction traveltimes (GOOGRAF) is used for the automatic determination of 2D velocity field models and interface structures of the subsurface geologic section in the study areas. In this method the homogeneous function automatically inverts first arrival refractions to derive a 2D velocity distribution which involves seismic boundaries. A complex set of observed refracted traveltimes along three seismic profiles (about 1200m length each) in the first investigated region and two long perpendicular profiles (3600 and 5400m length) in the second study region is used to construct refraction time field sections t(x, l) and 2D velocity field sections. Such kind of sections allows seeing complex layered structure of the subsurface section and allocation of boundaries and faults. Moreover, the interpreted geoseismic sections, where the interfaces between different seismic zones, faults and contact between different blocks of rocks are traced according to their own gradient and velocity range are also introduced. The resultant satisfactory models were successful in meeting the survey objectives. They provided the required details on the delineation and mapping the geometries of the inversion boundary of the deduced five seismic zones with velocities ranging from 200 to >4400m/s at the northwestern part, ,and provided the required details on the delineation and mapping the geometries of the inversion boundary of the deduced six seismic zones with velocities ranging from velocities ranging from 500 to >5600m/s at southern part, in which the significant structural complexities where large fault blocks were interpreted. Besides, two aquifers at different levels are also delineated at northwestern part; the upper water-saturated fluviomarine-continental sandstone of the Nubia group (upper Aquifer) was found at varied depths ranging from 50 to 120m increasing northward direction and has average thickness about 150m and the lower water-saturated sandstone layer of the Nubia group (lower Aquifer) was detected at depth varies between 200 t0 300m increasing to the north. It has thickness more than 150m in the eastern side