stripes
Occurrence number:
025-00-004
Country:
Brazil
Region:
Para
Location:
Longitude: -57.5, Latitude: 0.42
Carbonatite:
No
An oval intrusion of about 9x5 km, Cachorro is elongated northwest-southeast, with a smaller intrusion of about 4 km diameter to the south-southeast. It consists of quartz syenite with an amphibole and biotite, but it is not clear if the intrusions are peralkaline. A chemical analysis is given by Oliveira et al. (1975).
Age:
Rb-Sr on syenite gave 1479±34 Ma (Oliveira et al. 1975).
References:
ARAUJO, J.F.V., MONTALVAO, R.M.G. de, LIMA, M.I.C. de, FERNANDES, P.E.C.A., CUNHA, F.M.B. da, FERNANDES, C.A.C. and BASEI, M.A.S. 1976. DNPM. Projeto Radambrasil. Folha SA.21 Santarem. Levantamento de Recursos Naturais, Geologia, 10: 1-122.
OLIVEIRA, A. da S., FERNANDES, C.A.C., ISSLER, R.S., ABREU, A.S., MONTALVAO, R.M.G. de and TEIXEIRA, W. 1975. Folha NA.21 Tumucumaque e parte da Folha NB.21. DNPM Projet
Location: