de Barros Gomes, Celso, Alves, Francisco Rubens, Azzone, Rogério Guitarrari , Rojas, Gaston Eduardo Enrich, Ruberti, Excelso (2017) Geochemistry and petrology of the Búzios Island alkaline massif, SE, Brazil (Geoquímica e petrologia do maciço alcalino da Ilha dos Búzios, SE, Brasil) Brazilian Journal of Geology, 47 (1) 127-145 doi:10.1590/2317-4889201720160121
| Reference Type | Journal (article/letter/editorial) | ||
|---|---|---|---|
| Title | Geochemistry and petrology of the Búzios Island alkaline massif, SE, Brazil (Geoquímica e petrologia do maciço alcalino da Ilha dos Búzios, SE, Brasil) | ||
| Journal | Brazilian Journal of Geology | ||
| Authors | de Barros Gomes, Celso | Primary Author | |
| Alves, Francisco Rubens | Primary Author | ||
| Azzone, Rogério Guitarrari | Primary Author | ||
| Rojas, Gaston Eduardo Enrich | Primary Author | ||
| Ruberti, Excelso | Primary Author | ||
| Year | 2017 (March) | Volume | < 47 > |
| Issue | < 1 > | ||
| DOI | doi:10.1590/2317-4889201720160121Search in ResearchGate | ||
| Generate Citation Formats | |||
| Original Entry | Gomes, C. D. B., Alves, F. R., Azzone, R. G., Rojas, G. E. E., & Ruberti, E. (2017). Geochemistry and petrology of the Búzios Island alkaline massif, SE, Brazil. Brazilian Journal of Geology, 47, 127-145. | ||
| Classification | Not set | LoC | Not set |
| Mindat Ref. ID | 16095278 | Long-form Identifier | mindat:1:5:16095278:6 |
| GUID | 0 | ||
| Full Reference | de Barros Gomes, Celso, Alves, Francisco Rubens, Azzone, Rogério Guitarrari , Rojas, Gaston Eduardo Enrich, Ruberti, Excelso (2017) Geochemistry and petrology of the Búzios Island alkaline massif, SE, Brazil (Geoquímica e petrologia do maciço alcalino da Ilha dos Búzios, SE, Brasil) Brazilian Journal of Geology, 47 (1) 127-145 doi:10.1590/2317-4889201720160121 | ||
| Plain Text | de Barros Gomes, Celso, Alves, Francisco Rubens, Azzone, Rogério Guitarrari , Rojas, Gaston Eduardo Enrich, Ruberti, Excelso (2017) Geochemistry and petrology of the Búzios Island alkaline massif, SE, Brazil (Geoquímica e petrologia do maciço alcalino da Ilha dos Búzios, SE, Brasil) Brazilian Journal of Geology, 47 (1) 127-145 doi:10.1590/2317-4889201720160121 | ||
| In | Link this record to the correct parent record (if possible) | ||
| Abstract/Notes | The Late Cretaceous Búzios Island alkaline massif intrudes Precambrian charnockites and consists dominantly of syenitic rocks that are cut by a large number of dikes, mostly NE-trending, and representing two distinct suites, a felsic one and a mafic-ultramafic one. Alkali feldspar is the most abundant mineral; other constituents are clinopyroxene, commonly replaced by amphibole/ biotite, and opaques. Accessory minerals include occasionally rare phases bearing Zr, Ti, Nb and Rare Earth Elements (REE). The felsic dikes may also have nepheline (sodalite). The mafic-ultramafic suite, in particular the lamprophyres, shows a primary mineral assemblage with olivine, clinopyroxene and amphibole in addition to a groundmass having glassy material and carbonates (ocelli). The Búzios rocks are chemically evolved, mostly of potassic affinity and mainly belong to the miaskitic series. Variation diagrams for major and trace elements show a bimodal distribution, suggesting an origin from different magmatic pulses. The rocks are interpreted as having been derived by fractional crystallization processes from a basanitic parental magma. The SiO2-undersaturated and SiO2-oversaturated associations present in the massif are apparently not linked to a single magmatic source, and in the petrogeny residual system two trends are evident: the first one towards the phonolitic minimum and the second one towards the rhyolitic minimum, possibly pointing to amphibole fractionation. | ||
Map of Localities
Locality Pages
| Locality | Citation Details |
|---|---|
| Búzios island alkaline massif, Búzios island, Ilhabela, São Paulo, Brazil |
Mineral Occurrences
See Also
These are possibly similar items as determined by title/reference text matching only.
