Geoelectrical Exploration of Groundwater by Using Vertical Electrical Sounding Technique at Wadi Morra, South Sinai, Egypt

Research Article

Austin J Earth Sci. 2021; 4(1): 1025.

Geoelectrical Exploration of Groundwater by Using Vertical Electrical Sounding Technique at Wadi Morra, South Sinai, Egypt

Zayed MA*

Geology Department, Faculty of Science, Al-Azhar University, Cairo, Egypt

*Corresponding author: Mahmoud A. Zayed, Geology Department, Faculty of Science, Al-Azhar University, Al Mokhaiam Al Daem, Al Nasr Road, Nasr City, Cairo, Egypt

Received: May 31, 2021; Accepted: July 10, 2021; Published: July 17, 2021


Wadi Morra area is one of the most important areas targeted by the government for sustainable development. This development depends mainly on groundwater occurrences. This research aims to explore groundwater in this region, which depends on groundwater for its needs. To achieve this aim, the geoelectrical resistivity method was used, represented by Schlumberger Vertical Electrical Soundings (VESs). Seventeen VESs have been carried out with a maximum half current electrode spacing (AB/2) of 700m. The measured VESs are interpreted qualitatively and quantitatively to construct a geoelectrical model. To detect the water-bearing layers and their extensions, three geoelectric cross-sections in addition to a one-panel diagram were constructed using all the available data. Also, both true resistivity and isopach contour maps of waterbearing layers were created based on these data. The interpretation results indicate that there are five geoelectric layers (A, B, C, D, and E), two of them (C and D) are water-bearing layers. The first water-bearing layer is layer C, which represents the Nubian sandstone aquifer, and the second layer is layer D, which represents the fractured basement aquifer. These two aquifers were observed along the northern part of the Saint Catherine - Nuweiba road that dissects the Wadi Morra basin, while it is absent at the southern part of this road. It is due to the presence of a few faults. According to groundwater occurrences, the study area was divided into two zones. The first zone is zone (A) where the groundwater is present, either in the Nubian sandstone aquifer or in the fractured basement aquifer and the second zone is zone (B) where there is no groundwater at all due to the presence of basement rocks at a few depths. This research also recommends that the best places for drilling productive wells be at zone A.

Keywords: Groundwater; Geoelectrical resistivity; Vertical electrical sounding (VES); Nubian sandstone aquifer; Fractured basement aquifer


A new community of the Bedouins is currently being established at the Wadi Morra area, as it serves the considerable inhabitants that are living in the Wadi Morra, Wadi Saal, and surrounding area. Wadi Morra represents one of the main tributaries of the Wadi Dahab basin and is located in the northern part of the Dahab basin (Figure 1). Wadi Morra dissects the high basement terrains of south Sinai province and drains eastwards to Wadi Al Ghaib that is a drain to the Gulf of Aqaba via Dahab city. It represents an elongated structural sandy plain that takes NW-SE direction [1], and covers an area of about 30km2. Also, the main asphaltic road between Nuweiba and Saint Catherine is passing through this Wadi, for these reasons, this area is very important for development. Generally, the development of the arid and semiarid areas depends upon the groundwater occurrences and their proper utilization [2], Wadi Morra, and in general, South Sinai belongs to these areas. Groundwater is the only source of water in South Sinai and it is considered the key supply of safe drinking water for more than 104,000 people [3]. Also, groundwater is the only source of water in the Wadi Morra area, whether for drinking or other purposes. Therefore, groundwater exploration in this region is very important and vital for sustainable development. Many researchers explored groundwater in South Sinai, among them [2,4-7]. The results concluded, in its entirety, that there are three aquifers: the alluvial (Quaternary), the Nubian sandstone (Early Cambrian), and the fractured basement (Pre- Cambrian) aquifers. There is a high difference in the groundwater occurrences at the structurally controlled areas like Wadi Morra. This difference is due to the nature of the geological structures that affect many valleys in South Sinai, and the amount of annual precipitation, where you find in the same valley large differences in the groundwater occurrences, as well as the thickness of the water-bearing layers. Also, there is a previous recommendation for conducting geophysical studies and drilling wells to explore the Nubian sandstone aquifer in Wadi Morra’s depression [8]. From the above, the determination of water-bearing layers in such places is very important for sustainable development. In this manuscript, Vertical Electrical Sounding (VES) of the geoelectrical resistivity method was used for (1) groundwater exploration by detecting the areal extent and distribution of waterbearing layers at the foothills of the basement complex, and (2) detection of the probability for drilling production wells.