Compositional variations in Post Plateau Basalts of Somun Cura, Patagonia.

REMESAL, M.B.; PARICA, C.A.; SALANI, F.M.; CERREDO, M.E.

Kiel, Germany

Otro; th 20 Colloquium Latin American Earth Sciences; 2007

LAK

The basaltic plateau of Somun Cura is interpreted as a flood basalt on a wide extension at the Northern Argentine Patagonia, its development seems to be related to tectonic environment complex not fully explained. Since the former papers until today a good consensus was agreed about the existence of more than one episode in the formation of this magmatic sequence, 1) the basalt plateau with uniform composition and 2) the younger postplateau stage (Remesal et al. 2001, Salani et al. 2006). Into the post plateau stage it is possible to differentiate lithological variations. The most conspicuous difference let to separate the big trachyte-basalt complexes (represented at the ranges of Alta Sierra de Somun Cura, Apas, Chauchaineu, etc.) from the monogenetic minor centres (Trayen Niyeu, Corona Chico, Dos Hermanos and others).