- Indian Institute of Science Education and Research Bhopal, Earth and Environmental Sciences, Bhopal, India (abdul23@iiserb.ac.in)
Groundwater assessment in the Deccan basalt region of India is challenging due to its heterogeneous geology and complex aquifer dynamics. This study integrates hydrogeophysical methods, including DC resistivity and time domain Induced Polarization (DCIP) and slug tests, to evaluate aquifer potential near Bhopal, Madhya Pradesh. The research focuses on both shallow unconfined and deeper semi-confined aquifers within weathered and fractured basalt formations.
Electrical resistivity surveys included more than 25 DCIP profiles targeting weathered and fractured zones. Resistivity values ranged from 15–70 Ωm in weathered/fractured basalts and varied based on the degree of water saturation and fracturing, reflecting lithological heterogeneity. ERT profiles revealed low-resistivity and moderate-to-high chargeability zones, indicative of fracture porosity and groundwater retention. Fracture anisotropy and resistivity contrasts provided critical insights into aquifer connectivity and dynamics.
Slug tests conducted at a borehole with a drilled depth of 61 m validated geophysical findings. Hydraulic parameters, including hydraulic conductivity (3.9E-7 m/s), transmissivity (1.9E-5 m²/s), storativity (0.001), and specific storage (2.1E-5 m-1), were estimated using Bouwer-Rice and Cooper-Bredehoeft-Papadopulos solutions. These localized parameters complement the spatially extensive data from geophysical surveys. Seasonal water-level fluctuations emphasize the significance of monsoonal recharge in sustaining aquifers.
This integrated approach highlights the role of fractures, weathered zones, and advanced geophysical techniques in delineating groundwater zones and assessing recharge potential. The findings contribute to effective groundwater exploration and sustainable management strategies, addressing water scarcity challenges in basaltic terrains of the Deccan Traps.
Keywords: Aquifer potential, Bouwer-Rice and Cooper-Bredehoeft-Papadopulos solution, ERT, slug test, weathered/fractured basalts, hydrogeology.
How to cite: Khalique, A., Singh, A., and Gaurav, K.: Integrating Geophysical and Hydrogeological Methods for Groundwater Assessment in the Deccan Basalt Region of India, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17885, https://doi.org/10.5194/egusphere-egu25-17885, 2025.
