Shalateen area is located on the Red Sea coast at the southeastern part of the Eastern Desert. It is suffering from shortage in fresh water, where the main source of water is the rain water. Desalinated water is another source but it is more expensive. So, groundwater is the alternative solution to face the gap between the water demand and available water in this area. Vertical electrical sounding (VES) is considered as one of the most common methods in groundwater exploration. Twenty Schlumberger VES's with maximum current electrode spacing of 400 m were carried out in the coastal zone of Shalateen area at the alluvial fan of Wadi Rahaba. The obtained data were processed and interpreted qualitatively and quantitatively. The geoelectric layers that were detected in the study area are Quaternary dry alluvial sediments, Quaternary alluvial deposits and Miocene sandstone aquifer, clay lens, sill, fractured basement, non-fractured basement. The Quaternary alluvial deposits and Miocene sandstone represent the main shallow aquifer in the study area. The salt water appears at the eastern part while fresh water is concentrated at the western part. Resistivity values of the fresh to slightly brackish water ranges between 38.6 and 98.4 XÁm with thickness varies from 1.18 to 24.4 m and depth range between 1.31 and 19 m. Clay lenses appear in the alluvial fan channel with resistivity values ranges between 1.3 and 9.1 XÁm and thickness varies from 2.1 to 13.7 m. The fresh coastal aquifers are affected by set of faults. These faults appear in all profiles distributed orthogonally through the study area. In the study area, a fractured sill intrusion is intruding the groundwater aquifer. It is located near a granodiorite-tonalite exposure with resistivity values (230-315 XÁm) at (5.6-16.4 m) depth. Basement is also detected at shallow depths especially in the western part of the study area.

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Geoelectric technique has been used to detect the subsurface stratigraphy and structures around Dakhla Oasis, Egypt. 1D inversion approach has been applied to interpret the geoelectrical data obtained along 10 vertical electrical soundings (VES) using the well known Schlumberger array of AB/2 with electrode spacing varying from 3 to 400 m in successive steps.A preliminary quantitative interpretation of the vertical electrical sounding curves was achieved firstly by using two-layer standard curves and generalized Cagniard graphs. The final models were obtained in 1D using IPI2 WIN program. The modeling results were used to construct a geoelectrical section.Three geoelectric units were identified: The superficial geoelectrical layer is composed mainly of sand and gravel with relatively high resistivity values (7.61-346 X m) and thin thicknesses (0.252-9.19 m), of late Pleistocene to Holocene (Quaternary deposits).The second geoelectrical layer is composed of shale (Dakhla Shale). It is characterized by relatively very low electrical resistivity values (0.3-8.68 X m). The maximum depth of this layer ranges from 4.18 to 56.4 m.The Nubian sandstone (upper aquifer) third layer with moderate electrical resistivity values (68.5-1585 X m) can be detected at the maximum depth of penetration.

Asyuit area is considered as the most promising area for irrigated agriculture and development in both the Eastern Desert and the Western Desert. Groundwater is the most important resources necessary for such development. Forty-two vertical electrical soundings (VES.'s), using Schlumberger array were carried out in Asyuit area. The main goal of such survey was to elucidate hydrogeological information and to delineate subsurface structural elements. VES. curves were interpreted using a 2-D horizontal layering resistivity model assumption. The interpretation results showed that the geoelectrical succession consists of four layers. The top layer is formed of gravely sand with relatively high electrical resistivity values, the second layer is composed of sand (aquifer) with relatively intermediate electrical resistivity values, the third layer is made up of clay (aquiclude) with relatively low electrical resistivity values and the fourth layer consists of limestone with relatively high electrical resistivity values. As for groundwater potentiality, the second layer is highly promising to be the water-bearing layer. The maximum depth to water ranges between 9.9 to 522 m.

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