Estimation of Hydraulic Characteristics of Alluvial Aquifers from Electrical Resistivity Data

The applicability of geophysical techniques has been examined for evaluating aquifer properties like transmissivity and hydraulic conductivity of alluvial anisotropic aquifers of Saharanpur area, Western Uttar Pradesh. The available pumping test data for various tube well sites is reinterpreted by using different methods for obtaining the aquifer characteristics. The available vertical electrical soundings (VES) data in the vicinity of the sites of pumping tests have been interpreted and true resistivity and thickness determined for each site under both isotropic and anisotropic conditions. Three types of empirical relations from the data are established for estimating the hydraulic parameters from electrical data: (i) Relation between hydraulic conductivity and apparent formation factor; (ii) Relation between hydraulic conductivity and a modified aquifer resistivity; (iii) Relation between transmissivity and modified transverse resistance.

It is concluded that in an alluvial area where Darcy flow is deemed to be valid, hydraulic conductivity and transmissivity of aquifers can be estimated with reasonable accuracy at aquifer level by using relations between hydraulic properties and resistivity parameters.