GEOHYDROLOGICAL STUDIES OF HARD ROCKS IN KARANJA AND CHIKKAHAGARI BASINS, KARNATAKA

Abstract

In this work an attempt has been made to study the Geohydrological characteristics of hard rocks. For this study Karanja and Chikkhagari basins of Karnataka State, which are frequently subjected to drought, have been selected. Making use of specific capacity, unit area specific capacity and specific capacity index, well yields of different hard rocks have been studied. Estimation of aquifer parameters from (a) short duration pumping tests conducted on large dia-meter dug wells and (b) ground water balance, has been attemp_ ted. Recharge to ground water body from water balance method has also been attempted. The study indicates that there is wide variation in yield characteristics among the hard rocks and even within a rock type. Variation in yield is due to intensity of weathering and fracturing of rocks and their topographic location. Re-charge 0 ground water is also controlled by Geohydrological characteristics of rocks and their topographic disposition.