Since 2001, the
Nubian Sandstone aquifer situated between the
Toshka and
Abu Simbel areas of Egypt has undergone intensive drilling and development as part of a
land reclamation project. Drilling information was used to conduct a variety of studies regarding the hydrogeological setting of the area's aquifer. Results indicated that
lithological characteristics and
tectonic settings are having a substantial effect on groundwater flow patterns and the area's overall aquifer potentiality, which is considered relatively low when compared to neighboring areas in eastern
Oweinat or
Dakhla.
Geology The aquifer is largely composed of hard
ferruginous sandstone with great
shale and clay
intercalation, having a thickness that ranges between 140 and 230 meters. Groundwater type varies from fresh to slightly brackish (
salinity ranges from 240 to 1300
ppm). The
ion dominance ordering shows that
sodium cation is most commonly predominating over
calcium and
magnesium – whereas
chloride is predominant over
sulfate and
bicarbonate. The groundwater is of
meteoric origin (the term meteoric water refers to water that originated as precipitation; most groundwater is meteoric in origin). High concentrations of sodium, chloride, and sulfates reflect the
leaching and
dissolution processes of
gypsiferous shales and clay, in addition to a lengthy duration of water residence. Two recharge locations have been identified by
Reika Yokochi et al.: one 38,000 years ago originating from the Mediterranean, and the second dated at around 361,000 years ago from the tropical Atlantic. ==International development projects==