Assessment of groundwater potential zones in Vellore district, Tamil Nadu, India using geospatial techniques

The present study focuses on the exploration of groundwater potential zones in Vellore district, Tamil Nadu, India based on geospatial technologies. Various thematic layers such as landuse/ land cover, soil texture, slope, geology, geomorphology, drainage and lineament density, rainfall, transmissivity, permeability and specific capacity were derived from suitable sources. All the thematic layers and classified raster’s were prepared using ArcGIS version 10.1 software. The value in each thematic layer was assigned a common scale thus integrating all the thematic layers and to generate a final output layer. The score for each influencing factor were calculated based on multi-influencing factor technique. During weighted overlay analysis, the ranking was given for each individual parameter of each thematic map, and weights were assigned according to the multi-influencing factor (MIF). In this study, the groundwater potential zones were classified by four categories such as poor, moderate, good and excellent. Excellent groundwater potential zones have been observed in the eastern part of the study area due to the presence of good porosity and permeability. The obtained results were validated with specific yield of the aquifer in the study area. It is noted that there is a strong positive correlation between excellent groundwater potential zones with high specific yield and it diminishes with low specific yield with poor potential zones.