The Neogene Barril Niyeu Volcanic Complex. Somún Curá Magmatic Province. Northern Extra Andean Patagonia. Argentina.

SALANI, F. M.,; REMESAL M.; CERREDO, M.E.

BOLLETTINO DI GEOFISICA TEORICA ED APPLICATA

ISTITUTO NAZIONALE DI OCEANOGRAFIA E DI GEOFISICA

Año: 2010 vol. 51 p. 85 - 88

0006-6729

The mainly Oligocene (25-28Ma) Somún Curá basaltic plateau covers about 25000 km2 in the north of Extra Andean Patagonia (Argentina, Fig. 1). Several eruptive centers of different complexities were built over the basaltic plateau during Late Oligocene- (Early) Miocene which, according to the wide compositional and eruptive diversity may be grouped in two main types: a) large bimodal complexes and b) monogenetic eruptive centers. The former are characterized by their alkaline nature associated with a typical gap in the ∼ 53-60% SiO2 range.