Prioritization of sub-basins based on geomorphology and morphometricanalysis using remote sensing and geographic informationsystem (GIS) techniques

Abstract

Geomorphology and drainage characteristics of the Gurpur river basin have been studied using satellite images, topographic maps and geographic information system (GIS) techniques. Geomorphology and morphometric parameters have been used to prioritize the sub-basins (SB-I to -VII) and identify the most deficit/surplus zones of groundwater. The study reveals that 8% (SB-VII) to 85% (SB-II) area of the geomorphic units have poor to moderate groundwater prospect. About 16% (SB-V) to 92% (SB-VII) area were estimated as good to excellent zones for groundwater potential. Bifurcation ratio results show that geomorphic control predominates over structural control in the development of drainage network. Computed values of stream frequency of SB-II, SB-III and SB-VI indicate steep ground slopes, with less permeable rocks, while drainage density indicates that the river basin is moderately permeable. Sub-basin-wise prioritization reveals that SB-II is the most deficit zone, while SB-VII is found to be surplus zone of groundwater potential.