Impact of sea water intrusion on groundwater aquifers using geoelectrical techniques: A case study, the new port of Jarjob, El-Negila area, Marsa Matrouh, Egypt

This research investigates the effect of seawater intrusion on groundwater quality in the western coastal zone of the Mediterranean Sea, Egypt, between Wadi Abu Emera and Abu-Hesha. The objective of this research is to study the effect of seawater intrusion on groundwater quality, using geoelectrical techniques including vertical electrical resistivity soundings (VES) and time-domain electromagnetic methods (TEM). Ten Schlumberger VES with a current electrode distance of as high as 600 m and twenty TEM soundings with a single loop of 200 × 200 metres were carried out during this study. Processing and interpretation of the field data concluded that the geoelectrical succession of the area consists of three layers, where the bottom layer is the water-bearing formation. Also, the resistivity values decrease with depth and towards the Mediterranean Sea because of the seawater intrusion. This intrusion occurs along a system of faults that act as conduits to bring seawater inland. It is recommended to avoid the locations of these faults while drilling wells unless these wells are used for the desalination process. These faults serve as conduits for seawater to migrate inland. In contrast, the southern portion of the survey area is suitable for well drilling, provided that careful measures are implemented to maintain the wells' safe yield.