Study of Groundwater Potentiality and Sea Water Intrusion along the Coastal Plain, Wadi Thuwal, KSA- A Case Study Based on DC Resistivity

The present study mainly aims to outline zones that have groundwater potentiality with good quality and those which are affected by sea water intrusion. The electrical resistivity data were acquired over an area of about 170 km^2 of a coastal plain, Wadi Thuwal, which is bounded by the Red Sea in the west and the volcanic hills in the east. In such an area, resistivity measurements, using n-layering model, generally reveal a wide range of resistivity values which do not reflect the reality. Hence, the statistical analysis has to be involved to overcome this problem and to make the final interpretation reliable. In our case, the n-layer models were modified to other statistical geoelectric models (SLM), consisting of a number of layers equivalent to the stratigraphic layering beneath each VES site. The modified models were used to outline the depth to the bed rock, groundwater accumulation zones and water table as well as to define the effect of sea water intrusion through the study area.