Electrical Resistivity Tomography for Coastal Sea Water Intrusion Characterization along Rafah Area, South of Gaza Strip, Palestine

Abstract

Resistivity methods mainly electrical resistivity tomography 2D and resistivity sounding 1D represent the main geophysical tools to delineate seawater intrusion into freshwater aquifers. Thirty 2D imaging sections were applied with Wenner-Schlumberger array (NW-SE direction), distributed on six profiles (perpendicular to the coast) in southern part of the coastal aquifer in Gaza Strip (Rafah Governorates), supported by 4 Vertical electrical soundings points with Schlumberger array, to map shallow-depth seawater intrusion into freshwater aquifer and study the subsurface geologic formation. Analysis and interpretation of the electrical resistivity tomography 2D and 1D sounding results reveal that seawater intrusion zone appears at the western part of the study area and extends along Rafah coast with a difference distance and depths. The depths are ranging between (few meters to 20 m) in the western sections, while they are betwee 40 to more than 65 m in the eastern section. The resistivity data results were correlates well with the 3 boreholes data and 3 chemical analyses water samples.