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Please cite this article as: Angerer, T., Hagemann, S.G., Walde, D., Halverson, G.P., Boyce, A.J.,Multiple metal sources in the glaciomarine facies of the Neoproterozoic Jacadigo iron formation in the "Santa Cruz deposit", Corumbá, Brazil, Precambrian Research (2016), http://dx.doi.org/10. 1016/j.precamres.2016.01.002 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

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Banded iron formations (BIF) are the protolith to most of the world's largest iron ore deposits. Previous hypogene genetic models for Paleoproterozoic "Lake Superior" BIF-hosted deposits invoke upwards, down-temperature flow of basinal brines via complex silica and carbonate precipitation/dissolution processes. Such models are challenged by the necessary SiO 2 removal. Thermodynamic and mass balance constraints are used to refine conceptual models of the formation of BIF-hosted iron-ore. These constraints, plus existing isotope and halogen ratio evidence, are consistent with removal of silica by down-or up-directed infiltration of high-pH hypersaline brines, with or without a contribution from basinal brines. The proposed link to surface environments suggest that Paleoproterozoic BIF-ore upgrade may provide a record of a critical time in the evolution of the Earth's biosphere and hydrosphere.