Alkaline Rocks and Carbonatites of the World

Setup during HiTech AlkCarb: an online database of alkaline rock and carbonatite occurrences

Bom Repouso

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Occurrence number: 
025-00-127
Country: 
Brazil
Region: 
Sao Paulo
Location: 
Longitude: -46.16667, Latitude: -22.51667
Carbonatite: 
No

Bom Repouso is an alkaline suite belonging to the Serro do Mar Alkaline Province of the southern-central portion of the Brazilian Platform, intruded into Precambrian granitoids of the Paraisópolis Complex. It consists of a crescent-shaped main body (~1-2 km2) opening to the south, accompanied by two small (<100 m2) satellite plugs in the southeast. The complex is exclusively composed of sodic, agpaitic phonolites with mineral assemblages including arfvedsonite, aegirine, nepheline, astrophyllite, eudialyte and aenigmatite. Detailed descriptions and petrology can be found in Rosa (2012).

Age: 
79-76 Ma Ar-Ar (Rosa et al. 2014)
References: 
ROSA, P.A.S., 2012. Geologia E Petrologia Da Suíte Alcalina de Bom Repouso, MG. unpublished Masters thesis, University of São Paulo. ROSA, P.A.S., RUBERTI, E., VASCONCELOS, P. & THEIDE, D., 2014. 40 Ar / 39 Ar ages of Bom Repouso Alkaline Suite, MG state. South American Symposium on Isotope Geology 9 Program and Abstracts, 184
Map: 
Fig 1. Bom Repuso (Rosa, 2012, Fig 4.1)
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith