The vast 57 majority of IFs were deposited in the Neoarchean and Paleoproterozoic oceans between 2.80 and 58 1.85 Ga (Isley and Abbott 1999), and with the exception of an episode of global IF deposition 59 during the Neoproterozoic ice ages (e.g., Cox et al. [...] 92 Magnetite is a mixed-valence oxide of the spinel group and is one of the major iron-rich Always consult and cite the final, published document. [...] Within this orogenic belt, the Wutai 127 complex is characterized by greenschist- to lower amphibolite-facies in the middle part and is 128 regarded as a typical granite-greenstone belt, while the Fuping and Hengshan complexes that are 129 dominated by amphibolite to granulite facies are located in the southeast and northwest parts of 130 the belt, respectively (Bai 1986; Tian 1991; Bai et al. [...] The siderite layers of the Baizhiyan BIFs are sub-millimeter in thickness, and no 319 deformation caused by the displacive growth of siderite layers has been identified in the adjacent 320 layers (Fig. [...] Overall, the mineralogy and geochemistry of the Baizhiyan BIFs 332 is consistent with a model wherein iron cycling in a predominantly anoxic water column results 333 in the accumulation of early diagenetic magnetite, siderite and silica at the sediment–seawater 334 interface.
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