stripes
Occurrence number:
025-00-048
Country:
Brazil
Region:
Goias
Location:
Longitude: -51.13, Latitude: -16.28
Carbonatite:
No
Corrego dos Bois is a complex intrusion of the Ipora Group, 5 km in diameter and covering 20 km2, emplaced in Precambrian granites and migmatites. It has a border zone of pyroxenites, peridotites, theralites and essexites around a large dunitic core; there are subordinate nepheline syenites. The dunites are granular olivine rocks with seams of opaques and with a little augite, biotite, zeolite, plagioclase and (?)sodalite. The essexites, apart from labradorite, Ti-augite and a magnesian olivine, contain orthoclase, nepheline, sodalite, biotite, hornblende, cancrinite and opaques.
References:
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.
DANNI, J.C.M. 1978. Magmatic differentiation of the alkaline-ultrabasic intrusions of the Ipora region, south west Goias, Brazil.In. Proceedings of the First International Symposium on Carbonatites, Pocos de Caldas: 149-67
Map:
Fig. 1_196 The Ipora Group of occurrences of alkaline intrusions of central Goias.
Location:
References: