PGC Publishing PCGPCG
download
Back Next Next
The Epigenetic Sediment-Hosted Serra Pelada Au-PGE Deposit and its Potential Genetic Association with Fe-oxide Cu-Au Mineralisation within the Carajás Mineral Province, Amazon Craton, Brazi
 
by
Christian Grainger, David I Groves, University of Western Australia, Perth, WA, Australia. Carlos H C Costa, Companhia Vale do Rio Doce, Parauapebas, PA, Brazil

in   Porter, T.M. (Ed), 2002 - Hydrothermal Iron Oxide Copper-Gold and Related Deposits: A Global Perspective, PGC Publishing, Adelaide, v. 2, pp 227-245.

ABSTRACT

   The Serra Pelada Au-PGE deposit is located within the Carajás Mineral Province of the southeastern Amazon Craton, Brazil. Gold-PGE ores are epigenetic and display a strong structural control, being hosted in sub-greenschist facies carbonaceous and calcareous metasiltstone, within the hinge zone of a reclined, tight, regional-scale F2 synform. Although the entire orebody has undergone deep tropical weathering, some evidence of the original hydrothermal alteration is preserved. Gold-PGE mineralization is associated with the formation of magnetite- and hematite-rich hydrothermal breccias, massive zones of hematite metasomatism, intense sericite (white mica)-kaolin metasomatism, siderite veining and a jasperoid envelope of amorphous silica alteration hosting rare disseminated pyrite. All other Au-PGE ore-related mineral assemblages have undergone intense weathering to hydrated Fe-oxides and secondary clay minerals, preventing further description of primary ore and alteration features. The geochemistry of the primary Au-PGE ores at Serra Pelada displays many similarities to that of Fe-oxide Cu-Au deposits within the Carajás Mineral Province, and indeed world-wide, in terms of metal association (e.g. Co, Ni, Cu, U), LREE enrichment and associated Fe-metasomatism. The Au-Pd-Pt association also suggests ore metal transport in acid, oxidizing, chloride-rich fluids, similar to those for Fe-oxide Cu-Au deposits. In combination with these similarities, and the location of the Serra Pelada Au-Pd-Pt deposit, it is suggested that the latter represents a distal equivalent to the Fe-oxide Cu-Au deposits and, as such, a target that may have been overlooked during exploration programs around such terrains globally.



PorterGeo Home   |   PGC Publishing   |   Volume 1   |   Volume 2   |   Volume 3   |   Volume 4   |   Contact
PGC Logo
Porter GeoConsultancy Pty Ltd
 Ore deposit database
 Conferences & publications
 International Study Tours
     Tour photo albums
 Experience
PGC Publishing
 Our books and their contents
     Iron oxide copper-gold series
     Super-porphyry series
     Porphyry & Hydrothermal Cu-Au
 Ore deposit literature
 
 Contact  
 Site map
 FacebookLinkedin