Article
Occurrence of chromiferous horizon in the Trincheira Complex, municipality of Corumbiara, southeast of the State of Rondônia, Brazil
Registro en:
SILVA, Guilherme Ferreira da et al. Occurrence of chromiferous horizon in the Trincheira Complex, municipality of Corumbiara, southeast of the State of Rondônia, Brazil. Technical report, Brasília, n. 11, may 2017.
2448-2242
Autor
SILVA, Guilherme Ferreira da
RIBEIRO, Thyago de J.
CORRÊA, Lívio W. C.
SILVA, Dalton Rosemberg V. da
OLIVEIRA, Carlos E. S. de
Institución
Resumen
The Trincheira Mafic-ultramafic Complex comprises a Mesoproterozoic layered intrusion hosted in metasedimentary rocks of the southwestern portion of the Amazonian Craton. This intrusion has an outcropping area of approximately 35 km2 , however, it has been associated to a larger ellipsoidal magnetic anomaly with N-S elongated shape. The Trincheira Complex is com-posed of partially metamorphosed pyroxenites, websterites, gabbros and anorthosites. The complex hosts Cr-rich layers associated to relevant concentrations of Ni. High concentrations of Cu, Co and V have also been detected. Preliminary analysis performed with portable X-ray diffraction indicates up to 13% Cr and occurrence of cochromite, a special variety of chromite enriched in cobalt, nickel and iron, whereas ICP-MS analyses returned concentrations of up to ~3600 ppm Cr.