Item

Abstract

Underground aquifer, water lung of planet Earth, is facing mounting stress due to excessive groundwater withdrawal than recharge in many parts of the world. India, covered 2/3^rd by hard rock terrain with limited groundwater storage, are worst hit. To arrest groundwater depletion and attain resource sustainability, it is very important to generate precise knowledge of hard rock aquifer system predominantly controlled by fracture network, and aquifer parameters for realistic simulation of aquifer conditions and effective groundwater management plan. The Airborne electromagnetic survey is gaining increasing application for rapid and high-resolution mapping of aquifers system in 3D and its hydrogeological connectivity spatially from soil to deep aquifer at 100-300m below ground surface. The paper presents AEM imaging of fractured controlled crystalline aquifer system in granitic hard rock of southern India and translating AEM resistivity data into natural recharge coupled with rainfall magnitude. The AEM, having ability of rapid and dense data sampling with advance processing of spatially constrained inversion that accounts indirectly the degree of lithological variability in its surroundings, helps in improving spatial distribution of aquifer system and parameter at regional scale. The paper also presents the role of data density on its spatial relationship through variogram analysis. The quantitative knowledge of groundwater availability through improved estimates of recharge, will help farmers to plan suitable strategy to cultivate different kinds of crops with ensured yield.