Preliminary Hydrogeologic Investigations of Nubia Sandstone and fractured Basement Aquifers in the Area between El Shalateen and Halayeb, Eastern Desert, Egypt

Abstract

El Shalateen-Halayeb triangle is a promising district for tourism and agricultural development. Pre-Miocene rocks (fractured basement and Nubia sandstone) represent the main water-bearing formations in the investigated area. Rainfall and occasionally flash floods represent the main sources of recharge. Groundwater occurrence and movement in basement aquifer is mainly controlled by the structural elements, where interaction between fractures and intrusive dykes reflect a good environment for groundwater entrapment. In fractured basement aquifer, the transmissivity ranges from 2.75 m2/day to 784 m2/day. Such wide variation could be attributed to the lateral facies changes as well as the impact of the complicated structural setting. Nubia sandstone is detected as a water-bearing in Abraq, Abu Saafa and EL Dif localities, its transmissivity varies from 2.72 m2/day to 72.4 m2/day. Poor potentiality of aquifers is mainly due to high channel gradient, which gives no chance for groundwater replenishment. Regionally, the direction of groundwater flow is mainly restricted by the variable hydraulic gradients from locality to another.