V-rich minerals in contact-metamorphosed Silurian sedex deposits in the Poblet area, southwestern Catalonia, Spain
Por:
Canet C., Alfonso P., Melgarejo J.-C., Jorge S.
Publicada:
1 ene 2003
Resumen:
The Lower Llandoverian metasedimentary rocks of the Prades Mountains, southwestern Catalonia, Spain, consist of interstratified anorthite-rich beds, chert beds, phosphate beds, sulfide-rich black shale (with mainly pyrrhotite and minor chalcopyrite), massive sulfide lenses and calc-silicate beds. These metasedimentary rocks are anomalously enriched in V and Cr, and have disseminated minerals of precious metals: mainly sperrylite and palladian löllingite. The V-and Cr-rich associations are the result of an isochemical metamorphism of V-and Cr-rich protoliths. The contact metamorphism of V-rich shale produced metapelitic hornfels with V-rich aluminosilicates and V-Cr oxides. The occurrence of V oxides in apparent equilibrium with V-rich silicates suggests a limit for the V and Cr contents in these aluminosilicates at the conditions of thermal metamorphism. On the other hand, metamorphism of anorthite- and V-Cr-rich sedimentary rocks produced V- and Cr-rich silicates, such as goldmanite, V-rich amphiboles, V-rich titanite and V-rich allanite.
Filiaciones:
Canet C.:
Departamento de Recursos Naturales, Instituto de Geofísica, Univ. Nacional Autonoma de Mexico, México, DF 04510, Mexico
Alfonso P.:
Dept. Cristal-Lografia Min./Diposits, Universitat de Barcelona, Catalonia, Barcelona E-08028, Spain
Melgarejo J.-C.:
Dept. Cristal-Lografia Min./Diposits, Universitat de Barcelona, Catalonia, Barcelona E-08028, Spain
Jorge S.:
Depto. de Didacticas Especificas, Facultad de Humanidades y Educacion, C/ Villadiego s/n, Burgos E-09001, Spain
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