Targeting the bauxite rich pockets from lateritic terrain utilizing ASTER data: A case study from Kabirdham District, Chhattisgarh, India

The vast unexplored lateritic terrain of Kabirdham District, Chhattisgarh has received attention due to the presence of localized bauxite mines. In the present study, the ASTER images are processed to demarcate the ore, based on the spectral features of boehmite, gibbsite, and goethite in the VNIR–SWIR electromagnetic domain. This approach delineates the target and helps us to pinpoint the potential areas of bauxite deposits more easily from laterite. The bauxite ore is mainly enriched in Al2O3 (37.30–59.90%), TiO2 (4.30–13.40%), and Fe2O3 (1.75–29.07%), with low amounts of SiO2 (0.69–9.83%) of metallurgical grade. Boehmite is the predominant mineral in the study area followed by gibbsite. The band ratio, relative band depth images from ASTER data and the sub-pixel classifications of bauxite are mapped by using Adaptive Coherence Estimator (ACE), Matched Filtering (MF) and Linear Spectral Unmixing (LSU) methods. The bauxite-rich pixels derived from density-sliced images are overlaid on the digital elevation model (DEM) to interpret the relationship between the high-level bauxite distributions and the topographical slope/altitude. The results are validated by conducting substantial fieldwork. An integrated approach of spectral analysis with the petrological and colorimetric studies at Bamhantara block has supported the evidence of bauxite deposits and aided to find out the similar type of deposits at another lateritic province.