A Global View of Martian Surface Compositions from MGS-TES

TLDR

The study uses TES data from MGS to determine the compositions and distributions of Martian low‑albedo regions. The authors analyze TES thermal‑emission spectra to map these compositions across the planet. Two distinct low‑albedo surface spectral signatures were identified: a basaltic composition dominated by plagioclase feldspar and clinopyroxene, and an andesitic composition dominated by plagioclase feldspar and volcanic glass, with the basaltic signature confined to older surfaces and the silicic signature concentrated in the younger northern plains, roughly split along the planetary dichotomy.

Abstract

Thermal Emission Spectrometer (TES) data from the Mars Global Surveyor (MGS) are used to determine compositions and distributions of martian low-albedo regions. Two surface spectral signatures are identified from low-albedo regions. Comparisons with spectra of terrestrial rock samples and deconvolution results indicate that the two compositions are a basaltic composition dominated by plagioclase feldspar and clinopyroxene and an andesitic composition dominated by plagioclase feldspar and volcanic glass. The distribution of the two compositions is split roughly along the planetary dichotomy. The basaltic composition is confined to older surfaces, and the more silicic composition is concentrated in the younger northern plains.