Hydraulic and electric anisotropy of shallow fresh coastal aquifer in Nabq, Sinai, Egypt

Abstract

The prospective of this research is to investigate the hydraulic and electric anisotropy of the fresh coastal aquifer. In this context, 44 Schlumberger DC soundings associated with the available boreholes data and numbers of measured and/or calculated hydraulic and electric parameters were carried out in Nabq area, Sinai. The inverted DC soundings revealed high potentiality of the fresh coastal aquifer toward the western part of the Quaternary and Pre-Quaternary. An increased tortuosity (T) toward the west direction was associated with coarser grains size and increase in resistivity (ρ) hydraulic conductivity (K), transmissivity (T), and a decrease in porosity (ϕ). The longitudinal hydraulic conductivity (K l ) was found to be greater than the transverse hydraulic conductivity (K t) which implied a lower tortuosity in the horizontal direction than in the vertical direction. The decrease in the hydraulic anisotropy (λ H) was associated by an increase in transmissivity. Minor variation in electric anisotropy (λ e) could be observed as a result of alternating layers and intercalation of different grain sizes. Resistivity of the fresh aquifer was recognized by a liner direct relation with λ H, whereas, no clear relation could be observed with λ E. A polynomial relation with poor correlation coefficient could be observed between λ H and λ E.