Geochemical constraints on the genesis of the ‘Montaña de Manganeso’ vein-type Mn deposit, Mexican Plateau

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

“…This missing component likely includes Ni, Cl, and H (as water or OH groups) (see Section 3.6), all of which are challenging to quantify in ChemCam LIBS data. Typically, Fe and Mn rich veins form on Earth due to hydrothermal alteration of large ore bodies (Burisch et al., 2021; Madondo et al., 2020; Nadoll et al., 2014), alteration of existing magnetite‐rich igneous intrusions (Ovalle et al., 2018), or via hydrothermal alteration of pegmatite and ophiolites, associated with serpentinization (Gahlan et al., 2006; Hodel et al., 2017). However, each of these three options is difficult to explain in Gale crater.…”

Petrogenesis and 40Ar/39Ar dating of hydrothermal romanechite from the sub-aerial fault-related Romanèche Mn deposit (France)

“…4, Chermette, 1975) supports that romanechite was formed in the same temperature range than fluorite. These temperatures are most likely between 100 and 200 °C, according to data from other epithermal Mn deposits having similar mineralogical composition (Glasby et al, 2005;Hewett, 1964;Hewett et al, 1963;Hewett and Fleischer, 1960;Leal et al, 2008;Liakopoulos et al, 2001;Madondo et al, 2020;Papavassiliou et al, 2017;Voudouris et al, 2021). The dissolved fluorite crystals observed in some parts of the Romanèche deposit (Fig.…”

“…Arseniosiderite is found in some places and is a proof of hydrothermalism (Hewett, 1964). Below the high-valence Mn oxide ore, the deeper ore includes Mn 2+ -bearing minerals such as carbonates, silicate and oxides (Fusswinkel et al, 2013;Hewett, 1966;Madondo et al, 2020).…”

Geology and geochemistry of jasperoids from the ‘Montaña de Manganeso’ district, San Luis Potosí, north-central Mexico

“…CaO (<1.46 wt.%) concentrations can be accounted for by the presence of calcite and/or the Ca content in the lattice structure of some manganese oxides such as todorokite and birnessite. The low concentrations of K 2 O (<0.64 wt.%) reflect the absence of cryptomelane in the studied samples and possibly also the leaching of K to form illite, which is widespread as hydrothermal alteration at MdM (Madondo et al, 2020). Na 2 O (<0.2 wt.%) concentrations are very low, reflecting the presence of minor amounts of Na bearing minerals like birnessite and/or smectites (Table 1; Madondo et al, 2020).…”

“…Low TiO 2 (<0.035 wt.%) concentrations indicate limited lithogenic components whereas the moderate Al 2 O 3 (<1.9 wt.%) concentrations may be reflecting presence of hydrothermal kaolinite that is abundant at MdM (Madondo et al, 2020). The Al 2 O 3 concentrations in the MdM jasperoids may also be representing the detrital aluminosilicate fraction from the replaced host rock, as reflected by the positive correlation between Al 2 O 3 vs. TiO 2 , MgO, CaO and K 2 O (r: 0.66, 0.94, 0.81 and 0.72, respectively; Table 3) (Hein et al, 2000).…”