Late-stage magmatic to deuteric/metasomatic accessory minerals from the Cerro Boggiani agpaitic complex (Alto Paraguay Alkaline Province)

Autor(es)

Comin-Chiaramonti, Piero ; Renzulli, Alberto ; Ridolfi, Filippo ; Enrich, Gaston E. R. ; Gomes, Celso B. ; De Min, Angelo ; Azzone, Rogerio G. ; Ruberti, Excelso

• Tipo de documento: Artigo Científico
• Fonte: Journal of South American Earth Sciences; v. 71, p. 14-pg., 2016-11-01.

Resumo

This work describes rare accessory minerals in volcanic and subvolcanic silica-undersaturated peralkaline and agpaitic rocks from the Permo-Triassic Cerro Boggiani complex (Eastern Paraguay) in the Alto Paraguay Alkaline Province. These accessory phases consist of various minerals including Th-U oxides/silicates, Nb-oxide, REE-Sr-Ba bearing carbonates-fluorcarbonates-phosphates-silicates and Zr-Na rich silicates. They form a late-stage magmatic to deuteric/metasomatic assemblage in agpaitic nepheline syenites and phonolite dykes/lava flows made of sodalite, analcime, albite, fluorite, calcite, ilmenite-pyrophanite, titanite and zircon. It is inferred that carbonatitic fluids rich in F, Na and REE percolated into the subvolcanic system and metasomatically interacted with the Cerro Boggiani peralkaline and agpaitic silicate melts at the thermal boundary layers of the magma chamber, during and shortly after their late-stage magmatic crystallization and hydrothermal deuteric alteration. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 06/01459-3 - Quimica de minerais acessorios, parageneses, condicoes de cristalizacao e evolucao magmatica em intrusoes sieniticas alcalinas meso-cenozoicas da plataforma brasileira.
• Beneficiário: Gaston Eduardo Enrich Rojas
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 12/06082-6 - A província magmática Paraná-Etendeka no Brasil: relações temporais e petrológicas entre o magmatismo toleítico e alcalino e suas implicações geodinâmicas
• Beneficiário: Excelso Ruberti
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/18073-4 - Magmatismo alcalino da Plataforma Brasileira: petrologia e geoquímica
• Beneficiário: Celso de Barros Gomes
• Modalidade de apoio: Auxílio à Pesquisa - Regular