1. Late-stage magmatic to deuteric/metasomatic accessory minerals from the Cerro Boggiani agpaitic complex (Alto Paraguay Alkaline Province)
- Author
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Filippo Ridolfi, Gaston E.R. Enrich, Angelo De Min, Celso B. Gomes, Rogério Guitarrari Azzone, Piero Comin-Chiaramonti, Alberto Renzulli, Excelso Ruberti, COMIN CHIARAMONTI, Piero, Renzulli, Alberto, Ridolfi, Filippo, Rojas, Gaston, Gomes, Celso, DE MIN, Angelo, Guitarrari, Rogerio, and Ruberti, Ettore
- Subjects
010504 meteorology & atmospheric sciences ,Carbonates ,Geochemistry ,REE-bearing minerals, Zirconosilicates, Agpaitic Deuteric Metasomatic, Carbonatitic fluids, Cerro Boggiani Paraguay ,Magma chamber ,engineering.material ,010502 geochemistry & geophysics ,01 natural sciences ,Peralkaline rock ,chemistry.chemical_compound ,Cerro Boggiani ,Nepheline ,Titanite ,Metasomatism ,Zirconosilicates ,Deuteric ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Phonolite ,REE-bearing minerals ,Peralkaline ,Agpaitic ,Metasomatic ,Carbonatitic fluids ,Paraguay ,Agpaitic Deuteric Metasomatic ,Geology ,Cerro Boggiani Paraguay ,Silicate ,chemistry ,CRISTALIZAÇÃO ,engineering ,Zircon - Abstract
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.
- Published
- 2016