Abstract
Fluid inclusions hosted in specular hematite from auriferous (jacutinga) and barren veins in the Quadrilatero Ferrifero either contain fluid inclusions assemblages of high-temperature aqueous carbonic and multiphase high-salinity, high-temperature aqueous inclusions or multiphase aqueous fluid inclusions showing narrow ranges of salinity and homogenization temperatures. Fluid inclusions in quartz and hematite are characterized by uniform Na/K ratios and considerable SO4 contents indicating similar formation conditions and perhaps fluid origin from a common source. The formation of specular hematite veins may be related to retrograde metamorphic fluids being released during the Brazillian orogenic cycle (600–700 Ma). The Pb isotopic characteristics of all jacutinga-type samples is readily reconciliated in a simple model that (i) involves different Palaeoproterozoic or Archaean source lithologies for lead and gold and that (ii) possibly reflects contrasting depths of fluid percolation during the Braziliano, orogeny and (iii) heterogeneous Au distribution in the greenstone source.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
