Alkaline Rocks and Carbonatites of the World

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

Agua Emendada

stripes

Occurrence number: 
025-00-053
Country: 
Brazil
Region: 
Goias
Location: 
Longitude: -51.12, Latitude: -17.03
Carbonatite: 
No

This is a small eroded volcanic neck cutting Carboniferous sandstones and consisting principally of breccias and tuffs, but with some flows. The central part is composed of alnoite/monchiquite-type rocks containing phenocrysts of olivine, Ti-augite, pleonaste, perovskite and opaques in a groundmass of pyroxene, melilite and opaques. The flows are variably vesicular and contain phenocrysts of olivine, Ti-augite and (?)feldspathoid, in a groundmass of pyroxene, biotite, opaques and glass; anorthoclase xenocrysts are found in some areas.

References: 

GLASER, I., BEZ, L., MARQUES, V.J. and RIPPEL, C. 1970. Excursao No. 3: Regiao de Ipora. Anais Congresso Brasileira de Geologia, 2: 39-58.
PENA, G.S. and FIGUEIREDO, A.J.A. 1975. Projeto Goiama II, relatorio final. Departamento Nacional da Producao Mineral. Companhia de Pesquisa de Recursos Minerais, 1: 121-61

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith