English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/18704
Compartir / Impacto:
Estadísticas
Add this article to your Mendeley library MendeleyBASE
Citado 26 veces en Web of Knowledge®  |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Título

Distribution and mineralogy of platinum-group elements in altered chromitites of the Campo Formoso layered intrusion (Brazil): evidence for remobilization of platinum-group elements at low temperature

AutorGaruti, G.; Proenza, J. A.; Zaccarini, F.
Fecha de publicación9-nov-2006
EditorSpringer
CitaciónMineralogy and Petrology 89(3-4): 159-188 (2006)
ResumenPolyphase, penetrative hydrothermal metasomatism in chromitites of the Campo Formoso layered intrusion produced spectacular chromite – ferrian chromite zoning and transformed the primary intercumulus silicates into a chlorite – serpentine – carbonate – talc assemblage. Alteration did not substantially modify the composition of chromite cores and the distribution of platinum-group elements (PGE) through the sequence of chromitite layers, which still are consistent with magmatic fractionation processes. Texture and composition of laurite and Os–Ir–Ru alloys included in chromite cores indicate that these PGM were not altered, and are probably magmaticin origin. In contrast, the PGM located in the intergranular chlorite matrix (laurite, Ir–Ru–Rh sulfarsenides and Pt–Pd compounds with Sb, Bi and Te) display evidence of hydrothermal reworking. These PGM are intimately intergrown with low-temperature Ni-sulfides. The paragenesis suggests that the Ni-sulfides-PGM assemblage formed at the expenses of unknown PGM precursors, which must have been originally present in the intercumulus silicate matrix. Mechanism of formation involves a sequence of dissolution-precipitation events controlled by variation of redox conditions during chromite alteration. The presence of a secondary ore mineral assemblage consisting of galena, bismuthinite, native antimony, and various Pb–Sb compounds suggests a possible contribution of fluids derived from the adjacent granite.
Descripción30 pages, 14 figures, 7 tables.
Versión del editorhttp://dx.doi.org/10.1007/s00710-006-0141-9
URIhttp://hdl.handle.net/10261/18704
DOI10.1007/s00710-006-0141-9
ISSN0378-2697
Aparece en las colecciones: (IACT) Artículos
Ficheros en este ítem:
No hay ficheros asociados a este ítem.
Mostrar el registro completo
 



NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.