Alkaline Rocks and Carbonatites of the World

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

Banhadao

stripes

Occurrence number: 
025-00-101
Country: 
Brazil
Region: 
Parana
Location: 
Longitude: -49.38, Latitude: -24.65
Carbonatite: 
No

Banhadao is a multiple intrusion of some 11 km2 intruding the Tres Corregos granitic complex. Nepheline syenites are predominant and variable, aegirine-augite/aegirine and melanite being the principal mafic minerals with some sodic amphibole; nepheline may be altered to cancrinite and pectolite. Phlogopite melteigites and minor feldspar-melanite ijolites and malignites also occur. Phonolite dykes are present within and around the complex.

Economic: 
Geochemical work on soils has proved high concentrations of Nb, Ti, Zr and Al.
Age: 
Biotite from malignite gave 118±4 Ma by K-Ar and anorthoclase from foyaite 68±1 Ma (Hama et al. 1977).
References: 

HAMA, M., ALGARTE, J.P., PAIVA, I.P. and RODRIGUES, J.C. 1977. Idades K/Ar do macico alcalino do Banhadao e do complexo Bairro da Cruz. In Atas do I Simposio de Geologia Regional, Sociedade Brasileira de Geologia Nucleo de Sao Paulo, Sao Paulo: 170-8.
KAEFER, L.Q. and ALGARTE, J.P. 1972. Macico alcalino de Banhadao. Estudos preliminares. Anais Congresso Brasileiro de Geologia, 26(1): 57-64.
RUBERTI, E. and GOMES, C.B. 1984. O macico alcalino do Banhadao: geologia e petragrafia. Anais Congresso Brasileiro de Geologia, 33: 4400-12

Map: 
Fig. 1_218 Banhadao (after Ruberti and Gomes, 1984, Fig. 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