Groundwater aquifer assessment using hydrogeophysical investigations: the case of western Al Ain Sokhna area, Gulf of Suez, Eastern Desert, Egypt

Abstract

This study aims to assess the groundwater aquifer and defined the quality of water in the Gulf of Suez region. Hydrochemical and electrical resistivity techniques have been used for evaluating an aquifer, including its extension and quality, in the western Al Ain Sokhna area, Gulf of Suez. This study collected 16 groundwater samples from wells tapping the upper Miocene aquifer. Laboratory tests, including the estimation of electrical conductivity (E.C.), pH, total dissolved solids (TDS) and major ions such as Ca2+, Mg2+, Na+, K+, CO3 2–, HCO3 3–, SO4 2– and Cl–, were conducted. Most water samples belonged to the category of permissible water (TDS 500–1500 ppm) which represented 62.5% and brackish water which represented 37.5%. A total of 47 vertical electrical sounding stations were measured using the Schlumberger array of AB/2 up to 1500 m to detect the subsurface geologic section and delineate water-bearing layers. The results of geoelectrical interpretation illustrated that the subsurface section has five geoelectrical layers. The third layer represents the freshwater aquifer, and the fourth layer represents the brackish water aquifer. The upper Miocene aquifer represents the first aquifer with fresh groundwater of resistivities ranging from 14.7 to 100 Ω.m and thickness ranging between 28.4 and 86 m.