Metamorfismo de baja presion, su relacion con el desarrollo de la Cuenca Puncoviscana, plutonismo y regimen tectonico. Argentina

Abstract

In the Cordillera Oriental Argentina (22 and 26°S), the Puncoviscana Formation Basin was developed, in which an extensioinal tectonic setting would have been supported from Upper Precambrian to Middle Ordovician. That is suggested by the limited crustal thickening, the insignificant uplift after deformation, the sedimentary -synchronous basic-alkalic lavas and the growth of a low-pressure high-temperature metamorphism that culminates in anatectic migmatites, which have no explanation but the only magmatic heat derived from the trondhjemite-granodiorite diapirs intruded during the Middle Ordovician. -English summary