Role of Electrical Resistivity Method for Groundwater Exploration in Paithankheda area, of Gangapur Taluka, Aurangabad District, Maharashtra, India

Abstract

In this study the data generated while conducting electrical resistivity surveys through Vertical Electrical Sounding (VES) at 22 sites in different location along with a available geological &hydro-geological information of Paithan Kheda village were analyzed. The objective are (i)to understand the nature and extent of aquifer(ii)to find out the location and thickness of unsaturated zones and (iii)to evaluate and extent of appropriate artificial recharge structures at suitable locations across the village. Interpretation of the top sounding curves indicates presence of three to four subsurface geo-electric layers across the study area. The top soil ;layer has range of resistivity values from 2 to 30-ohm m & litho logy comprise clay with kankar, lateritic sand. This is followed by the weathered and jointed Basalt layers with resistivity values 100 300-ohm m could be is identified below the depth of 45m.At some places,doleritic dykes were also observed with resistivity values >300-ohms. The interpretation of VES data when correlated with the available lithilog data indicates a prominent water bearing zone between 30 and 45 mbgl.The underlying hard and compact Basalt has very little possibility of occurrence of groundwater. The top unsaturated and unconfined granular zone up to a depth of 30mts could therefore be easily recharged artificially through rainwater harvestining measures thereby augmenting the grounwater resources of the existing aquifers.Site specific artificial recharge measures from amongst counter bunding ,gully plugs ,check dams, percolation tank. Recharge shafts&subsurface dekes have been identified across the village for effective recharge of the aquifer especially in its north eastern &southern blockregions.Considering the deteeoriating grounwater sitution,these initiatives would be significant in catering the needs of future generations.