Mars Science Laboratory CheMin Data From the Glen Torridon Region and the Significance of Lake‐Groundwater Interactions in Interpreting Mineralogy and Sedimentary History

The Glen Torridon (GT) region in Gale crater, Mars is a with strong clay mineral signatures inferred from orbital spectroscopy. CheMin X-ray diffraction (XRD) instrument onboard the Science Laboratory rover, Curiosity, measured some of highest abundances to date within GT, complementing detections. GT may also be unique because XRD patterns samples, identified new phases, including: (a) Fe-carbonates, and (b) phase novel peak at 9.2 Å. Fe-carbonates have been previously suggested other instruments onboard, but this first definitive reporting by Fe-carbonate. This Å reflection has never observed crater for Mars, discrete identification still remains enigmatic no single on Earth able account all mineralogical, geochemical, sedimentological constraints. Here, we modeled profiles propose an interstratified mineral, specifically greenalite-minnesotaite, as reasonable candidate. coexistence Fe-carbonate Fe-rich minerals samples supports conceptual model lacustrine groundwater mixing environment. Groundwater interaction percolating lake waters sediments common terrestrial settings, diffusion two distinct water bodies subsurface can create geochemical gradient front sediments. Ultimately, proximity zone controlled secondary preserved sedimentary rocks exposed GT.