Application of Electrical Resistivity Method for Assessment of Shallow Groundwater in Southern Part of Punjab Province, Pakistan

摘要

The hydrogeology and groundwater quality of Lower Punjab,north of Pakistan,is important for the characterization of aquifer systems in order to explore fresh water resources.In order to understand the underground water quality,53 Vertical Electrical Sounding (VES) data was reprocessed by multiplication of geometric factor with observed resistivity data and interpreted along with litho-log data by resistivity lithology calibration.Litho-log data shows that the sedimentation pattern in the study area is heterogeneous mainly comprised of coarse and fine grained sand,silt,clay,clayey sand and some mixed facies.The correlation results of Iso-resistivity and Electrical conductivity (EC) maps at various depths show that high resistivity zones (resistivity ＞ 45 Ohm-m) and EC (＜1.5 dS/m) in aquifer layers are considered as fresh water zones and safe for irrigation as these zones correspond to comparatively large grain size sediments.To drill more boreholes for enhancing the fresh water exploration in the study area it is important to carry out time based resistivity measurements accompanied by some laboratory analysis.