Thermal Emission Measurements of Foidite Rocks: Possible Martian

Introduction: A TES spectral study of low albedo (LA) deposits within the Amazonis Planitia of Mars revealed that the derived bulk composition of these deposits contain very low silica contents (Fig. 1), classifying some of the deposits as foidites [1]. A foidite is an igneous rock in which feldspathoid minerals constitute ≥60% of the light-colored mineralogy; it is the inclusion of feldspathoids in place of feldspars that lowers the silica content of these silica-undersaturated rocks. Currently, the TES spectral library lacks spectra of feldspathoid minerals and so none were available for the spectral unmixing of these deposits. To assess the significance and effect of unmixing spectra of silica-undersaturated rocks without feldspathoid spectra, we conducted a subsequent thermal emission study of the Honolulu Volcanic (HV) series, which include samples ranging from foidite to basalt (Fig. 1).