FUMAROLIC ALTERATION ON MARS: LESSONS LEARNED FROM TERRESTRIAL ANALOG FIELDWORK
The identification and interpretation of hydrated mineral assemblages, within ancient aqueous environments on Mars, are key to the evolution of the Martian surface and its past habitability. To contribute to the identification of fumarole and hot spring deposits on Mars, we surveyed their mineral assemblages at a few terrestrial analog sites: the Solfatara Volcano (Campania, Italy), and Pico Alto Volcano and Furnas Volcano (Azores archipelago, Portugal). Several mineral identification techniques (VNIR and Raman spectroscopy, XRD) were used in the field and in the lab, and their individual merit was assessed. Characterization of the collected rock samples revealed a variety of mineralogical assemblages and alteration patterns at the three sites, which are best explained by the influence of temperature, bedrock composition and texture, and possibly the duration of hydrothermal activity.
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