MASTCAM SPECTRAL DIVERSITY OF ROCKS THROUGH CURIOSITY'S EXPLORATION OF GLEN TORRIDON

NASA's Curiosity rover is exploring a 5-km tall sedimentary mound in the center of Gale crater, known as Mt. Sharp, hypothesized to have formed via primarily lacustrine and aeolian processes. Orbital data of lower Mt. Sharp indicate phyllosilicate- and sulfate- bearing strata (Bibring et al., 2006). The phyllosilicate -sulfate transition has been observed in several locations on Mars, indicating a global environmental change around the Noachian-Hesperian transition (around 3.7 Ga) from a more wet climate that accommodates clay mineral formation to a drier, more acidic environment that allows sulfates to precipitate (Milliken et al., 2010; Chevrier et al., 2007). The Mast Camera (Mastcam) is an imaging instrument on Curiosity that can collect visible to near infrared (VNIR) multispectral observations, which provide broad mineralogic interpretations and context for other instruments. Our goal is to compare previously established Mastcam multispectral classes of rocks (Rice et al., 2022) to newer spectra from the phyllosilicate- rich region, known as Glen Torridon, and the overlying sulfate- bearing unit, thus enhancing our understanding of ancient geologic processes and habitability of the surface of Mars. Initial results reveal variation in three of the nine rock classes, potentially influenced by nontronite and/or other phyllosilicates, and Mg- and Ca- sulfates. Using WWU's goniometer, these hypothesized constituents will be tested by collecting VNIR spectra on multiple mineral mixtures.