Evaluation of hydrogeomorphologicall and forms and lineaments using GIS and Remote Sensing techniques in Bargur -Mathur subwatersheds, Ponnaiyar River basin, India

The Landsat ETM satellite data is used to demarcate hydrogeomorphologica11andforms and lineaments to evaluate groundwater potential of the study area. The Bargur -Mathur subwatersheds of Ponnaiyar river basin is occupied mostly by hard rocks and half of the portion in the study area is covered mainly by both wet and dry cultivation. The major hydrogeomorphic units identified in the area are, Structural Hills, Denudational Hills, Residual Hills, Inselberg, Pediments, Buried Pediment Inselberg Complex, Pediplains, Yalley Fills, Linear Ridges, Boulders and Rocky Knobs. Most part of the study area is occupied by pediplains with various thicknesses and the ground water potential is directly related to thickness of pediplain. Field observations showed that ground water occurs under unconfined conditions with water table at shallow to deep depth. From the lineament map, the lineament density and lineament intersection maps prepared to understand the impacts on groundwater percolation. Finally, the hydrogeomorphology and Lineament maps are overlaid following the weighted index overlay method, which delineates groundwater potential zones. An integrated remote sensing and geographic Information System (GIS) based approach has been used for demarcating groundwater potential zones in the study area.