Combining SWIR and TIR spectral features for regnizaion of phyllosilicate of martian surface

Abstract

Phyllosilicate is a principal form of hydrous minerals on the martian surface. It's also an indicative mineral in comparing different sediments and degree of aqueous alteration. Shortwave infrared (SWIR) and thermal infrared (TIR) spectral bands have distinct spectral response to the mineral groups and ions. However, combining SWIR and TIR to recognize phyllosilicate has been rarely studied. Based on the USGS spectral library, facing sensors of Mars: Compact Reconnaissance Imaging Spectrometer for Mars(CRISM) and Thermal Emission Imaging System(THEMIS), we conducted the research on the mechanis m of the spectral response of phyllosilicate, and established the SWIR and TIR identification model respectively, then combined the SWIR and TIR spectral features to build the combined recognition model of phyllosilicate by Fisher discriminant analysis. The results show that the identification accuracy of the combined model is the highest, which can correctly classify 90.6% of the mineral samples and improve the identification accuracy of phyllosilicate effectively.