Himalayan Geology, Vol. 39 (1), 2018, pp. 92-100, Printed in India
Geospatial analysis and hydrogeochemical investigation ofa part of southern Mahanadi delta, Odisha, India
J.K. SAHU1, P.P. DAS2*, H.K. SAHOO3, P.P. MOHAPATRA4, S. SAHOO5
1NTPC Ltd., Noida, Uttar Pradesh – 201 301, India
2Amity Centre for Ocean-Atmospheric Science and Technology, Gurugram 122413, India
3Department of Geology, Utkal University, Bhubaneswar 751004, India
4Sector 82, Gurugram, Haryana 122004, India
5Geological Survey of India, Faridabad 121001, India
*Email(Corresponding Author): prabhuprasaddas@gmail.com
Abstract: The Quaternary alluvial deposits of Mahanadi delta along the east coast of India are very intricate with regard to its depositional history. Present research carries out a comprehensive hydrogeological investigation of the coastal aquifer system belonging to the southern part of this deltaic deposit encompassing 6 administrative blocks of Jagatsinghpur district, Odisha. The study follows an integrative approach combining representative groundwater sampling, geophysical, geochemical and geospatial analysis to appreciate the hydrogeochemical functioning of the aquifer system. The geophysical investigation points towards a varying composition of sand, silt and clay fabricating alternating lithic units of granular and nongranular horizons. The subsurface lithology also exhibits several spatially heterogenous fragmented clayey masses forming numerous perched aquifers. Hydrogeochemical analysis indicates spatial dominance of strong acids, alkali and alkaline earth anions imparting profound saline influence on the groundwater. Major ion chemistry, hydrochemical diagrams and spatial distribution of the predominant hydrochemical variables is suggestive of a gradual freshening of the aquifer system across the northern part as well as occurrence of acid-base, surface, dissolution and cation exchange reactions across the aquifer system.
Key words: Geospatial; Hydrogeochemistry; Mahanadi; Aquifer; Groundwater; Cation Exchange.
