Mapping alteration minerals using sub-pixel unmixing of ASTER data in the Sarduiyeh area, SE Kerman, Iran

Implementation of reflection spectroscopy based new ASTER indices and principal components to delineate chromitite and associated ultramafic–mafic complex in parts of Dharwar Craton, India

“…in addition to map different alteration zones associated with Pb-Zn, Porphyry Cu, Au deposits (Guha et al, 2013;Rajendran et al, 2012Rajendran et al, , 2011Tangestani et al, 2011). Such wide utilization of ASTER data in geoexploration is possible for its mineralogically sensitive wavelength specification of VNIR, SWIR bands; which were effective in mapping surface alteration zones of hydrothermal deposits, residual enrichment deposits (Guha et al, 2013;Amer et al, 2010;Bedini, 2011;Brandmeier, 2010;Chen et al, 2007;Hosseinjani and Tangestani, 2011;Hashim, 2011, 2012). This can be substantiated from the fact that the wavelengths of diagnostic absorption features of sulphates, clay minerals, iron oxides, carbonates, aluminum and magnesium hydroxide bearing minerals coincide with the central wavelength of ASTER VNIR-SWIR bands.…”

“…Detail records of band ratios used in delineation of different rocks, economic minerals are available in the literatures (Guha et al, 2013;Kalinowski and Oliver, 2004;Pour and Hashim, 2012). Spectral mapping algorithms; which have been coined for classifying hyperspectral data (characterized with spectrally contiguous bands with 10 nm spectral resolution) have also been successfully used for classifying ASTER data to delineate potential areas of mineralization (Guha et al, 2014;Haselwimmer et al, 2011;Hewson et al, 2005;Hosseinjani and Tangestani, 2011;Kavak, 2005).…”

Comparative analysis on utilisation of linear spectral unmixing and band ratio methods for processing ASTER data to delineate bauxite over a part of Chotonagpur plateau, Jharkhand, India

“…ASTER data have been widely used for mapping economic rocks, alteration zones associated with mineralization using both per-pixel and sub-pixel mapping methods (Kalinowski & Oliver 2004;Galvão et al 2005;Hewson et al 2005;Azizi et al 2010;Mars & Rowan 2010;Aboelkhair et al 2011;Bedini 2011;Hosseinjani & Tangestani 2011;Pour & Hashim 2012;Pal et al 2011;Rajendran et al 2012;van der Meer et al 2012;Guha et al 2013). Recently, few attempts have also been made to delineate lateritic bauxite using spectral features.…”

Lithological Discrimination and Mapping using ASTER SWIR Data in the Udaipur area of Rajasthan, India

“…The ASTER sensor acquires earth's surface imagery in the VNIR, SWIR and TIR wavelength regions and has offered a great opportunity of using these datasets for mapping of various lithological units 1,7,26 , minerals 5 , hydrothermal alteration such as propylitic, argillic, phyllic and potassic zone 4,15,16,19 . Various image enhancement techniques such as Principle Component Analysis (PCA), Minimum Noise Fraction (MNF), Band Ratios (BRs), Band Combinations (BCs) and Spectral Indices (SIs) 6,7,18,19,27 ; spectral mapping algorithms such as Spectral Angle Mapper (SAM), Spectral Feature Fitting (SFF), Matched Filter (MF), Constrained Energy Minimization (CEM), Linear Spectral Unmixing (LSU), Mixture Tuned Matched Filter (MTMF) have been well employed on ASTER datasets to obtain the lithological, mineral and hydrothermal alteration maps with reasonable accuracies 5,8,12,[15][16][17]28 . Most of the full and sub-pixel spectral algorithms require target spectra or endmember to detect and classify them, which needs a rigorous procedure of spectral data extraction either from image, laboratory or spectral library 14 .…”