Abstract:
The objective of this study is to develop surface electrical resistivity methods for estimating hydraulic -conductivities in alluvial aquifers. The hydrogeological framework in the Ganga-Yamuna Interfluve is evaluated in view of formulating and testing relationships between hydraulic parameters and geo-electric parameters for alluvial aquifers under anisotropic conditions.
Resistivity of the aquifer is determined from results of Schlumberger electrical soundings conducted at twenty three sites in parts of Ganga-Yamuna interfluve, North India where pumping tests had previously been made. The data of pumping tests were analyzed using different methods including Neuman's (1975) method to calculate vertical hydraulic conductivity. The resistivities of collected water samples were determined to compute the formation factor. Computed formation factor were correlated with hydraulic conductivity. The formation factor is directly related to hydraulic conductivity. The normalized aquifer resistivity, normalized transverse resistivity, normalized longitudinal resistivity was correlated with hydraulic conductivity, and normalized transverse resistance with aquifer transmissivity. A four parameter empirical relation between hydraulic conductivity, modified longitudinal resistivity, modified transverse resistivity, and hydraulic anisotropy is developed for anisotropic aquifers underlain by conductive layer (clay). Results indicate that electrical parameters determined from soundings can be used to predict aquifer parameters.
