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Mineralogical characterization of weathered outcrops as a tool for constraining water chemistry predictions during project planning

Tamara Diedrich·Paul Fix·Andrea L. Foster
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Abstract

Weathered samples from naturally exposed outcrops of troctolite associated with a magmatic Ni-Cu sulphide deposit were characterized by synchrotron-based micro-X-ray fluorescence mapping (µ-XRF) and X-ray absorption spectroscopy (XAS), as well as by lab-based X-ray diffraction, electron microscopy, Raman spectroscopy and wet chemical methods. Metal mobility in weathered samples was assessed using a sequential leach procedure. Results are interpreted in the context of predictions for future mine water chemistry and used to refine the conceptual model for metal mobility following weathering of waste rock at a potential future mine site.

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Tamara Diedrich, Paul Fix, Andrea L. Foster. 2017. Mineralogical characterization of weathered outcrops as a tool for constraining water chemistry predictions during project planning. https://pubs.usgs.gov/publication/70194514

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