Overview of the Morphology and Chemistry of Diagenetic Features in the Clay‐Rich Glen Torridon Unit of Gale Crater, Mars

Abstract

 Glen Torridon in Gale crater underwent multiple generations of diagenesis of the bedrock, which widely varies in chemistry and morphology  We hypothesize that an initial enrichment of elements occurred during the Gale's postimpact hydrothermal alteration phase of evolution  We estimate that at least one type of vein in Glen Torridon required warm temperatures and highly reducing and alkaline fluid to form

Statistical Analysis of APXS‐Derived Chemistry of the Clay‐Bearing Glen Torridon Region and Mount Sharp Group, Gale Crater, Mars

“…The Hutton interval (Glasgow_Hutton) (sols-2660-2691) is a layer of Glasgow bedrock and complex vein networks that occurs at the top of Tower butte (Tables 1-4 and S1-S2; Figures 1, 2, 3-5, 6j and S5) below the Siccar point unconformity and in contact with the overlying Greenheugh pediment (GP) (see also Thompson et al, 2022 for further discussion). Although this interval contains the characteristic thin laminations that mark it as part of the Glasgow, a unique geochemical and mineralogical signature was documented here by APXS (this paper; Thompson et al, 2022), ChemCam (Dehouck et al, 2022;Gasda et al, 2022) and CheMin (Thorpe et al, 2022). Relative to mean underlying Glasgow bedrock, Hutton interval bedrock (n = 9, excluding veins) is enriched (i.e., >10% difference between mean Glasgow and Hutton) in Mn, Mg, Na (x25%-35%), P (x10%), and depleted in Cl, Ni, Zn, Br (x21%-30%).…”

Evolved Gas Analyses of Sedimentary Rocks From the Glen Torridon Clay‐Bearing Unit, Gale Crater, Mars: Results From the Mars Science Laboratory Sample Analysis at Mars Instrument Suite

“…This could have occurred in a stage of the lake environment, perhaps during an evaporative event, a partial freezing event, or during later diagenesis. It is possible this siderite may have been originally more abundant than now observed in GT rocks, since it tends to be replaced by ferric iron oxyhydroxides and oxides, and/or Fe 3+ ‐bearing clay minerals if interacted with higher pH and more oxidizing fluids (Gasda et al., 2022). This process could have also contributed to the heterogeneity in siderite abundances now observed in Jm and KHm rocks.…”

“…In the Jura member KM sample, and Knockfarril Hill member GR and MA samples, CheMin also made the first detection of a phase giving a sharp XRD pattern peak at 9.2 Å consistent with minnesotaite interstratified with minor greenalite (G‐M) (Thorpe et al., 2022) or Fe talc interstratified with minor serpentine (S‐T) (Bristow et al., 2021). The area in the KHm where the GR and MA samples were collected exhibited dark‐toned Mn‐rich nodules and Mn‐rich bedrock, and ChemCam instrument observations of a large fraction of the nodules also showed elevated phosphorous (Gasda et al., 2022). Despite these increased concentrations of Mn and P, CheMin data were not interpreted to indicate a crystalline Mn, P bearing phase (Bristow et al., 2021; Thorpe et al., 2022).…”

“…The Gm consisted of faintly laminated mudstone (Fedo et al., 2022). A variety of diagenetic features were observed in GT including nodules and vein fills (Gasda et al., 2022). Gm exhibited a significant number of diagenetic features which were less common in the underlying KHm (e.g., Gasda et al., 2022; O’Connell‐Cooper et al., 2022).…”

From Lake to River: Documenting an Environmental Transition Across the Jura/Knockfarril Hill Members Boundary in the Glen Torridon Region of Gale Crater (Mars)

“…For this work we focus on specific oxides (SiO 2 , MgO, CaO, Na 2 O, and K 2 O) to be used as geochemical markers characteristic of the sedimentary facies. In-depth analyses of the bulk bedrock geochemistry performed in the GT region are detailed in the companion work by Dehouck et al (2022) and also in Gasda et al (2022).…”