干旱区生态环境知识资源中心

This work addresses the detection of aquifers and the delineation of subsurface structures predominant in the basement rocks and their relations with these aquifers at the Bahariya Oasis, Western Desert, Egypt, and the relationship between the subsurface structures and the aquifers. In this respect, land geomagnetic and geoelectric-reconnaissance surveys were carried out over the oasis. Additionally, wells and bore-hole logs were used to verify the results and to explore the distributions of the subsurface reservoirs and the geological sequences. The results illustrate that the main groundwater aquifers in the fractured limestone ranges from 40 m to 90 m in depth and in the saturated Nubian sandstone from 800 m to 1200 m in depth. The thickness of the Carbonate reservoir varies from 90 m to 160 m. The Nubian sandstone formation that unconformably overlies the basement rocks has a thickness of approximately 250 m. In general, the depth to the basement rocks ranges from 1.2 km and 2.9 km in certain local areas according to the magnetic data. The structure trend analyses show that the dominant tectonic trends are northeastward and northwestward. These structures play an important role in controlling the aquifer depths and most probably supply water from the deeper Nubian aquifer to the shallower Carbonate aquifer.