Estimation of Mineral Abundance From Hyperspectral Data Using a New Supervised Neighbor-Band Ratio Unmixing Approach

Abstract

This article compares the ability of nine unmixing models, including radiative transfer (RT) models as well as a new nonlinear unmixing approach called neighbor-band ratio unmixing (NBRU), to obtain mineralogical information from hyperspectral data. Their performance in estimating mineral abundances of 94 crafted mineral mixtures was first assessed. NBRU led to the best results among non-RT models with mean and median errors of 9.8% and 7.4%, respectively. Hapke’s and Shkuratov’s RT models obtained 6.5% and 5.6%, and 6.7% and 4.7%, respectively. In a second experiment, the mapping ability of six non-RT models and their robustness when facing endmember variability were evaluated. The assessment was performed on an AVIRIS hyperspectral image of the widely studied Cuprite area, NV, USA. Comparisons with validation maps showed that NBRU retrieved the best spatial distributions for seven of the nine minerals mapped.