Determining Mineral Types and Abundances from Reflectance Measurements

Mineral types and their abundances were quantitatively determined from laboratory reflectance spectra using principal components analysis (PCA). PCA reduced the measured spectral dimensionality and allowed testing the uniqueness and validity of spectral mixing models. In addition to interpreting absorption bands, in this new approach we interpreted variations in the overall spectral curves in terms of physical processes, namely changes in mixtures of minerals, in particle size and in illumination geometry. Application of this approach to reflectances of planetary surfaces allows interpretation to be extended to quantitative determinations of mineral types and abundances.