Abstract

NIEMEYER, Hans  and  SANHUEZA, Marcos. La orogénesis Famatiniana en la Puna occidental de Argentina y en el norte de Chile. Rev. Asoc. Geol. Argent. [online]. 2016, vol.73, n.3, pp.341-347. ISSN 0004-4822.

In this paper the Famatinian orogeny that developed during an intra-Ordovician tectonism in an Ordovician continental magmatic arc along the western border of Gondwana is analized. In the Puna, this orogeny ends with the Ocloyic phase, that is characterized by a tight nor-northeast folding with axial planar cleavage that was synchronic with plutonic and hypabissal magmatism. K-Ar determinations in plutonic magmatism show a probable ~440 Ma rejuvenated age for this phase. Two other Ordovician events are recognized. The first one consists in a Floian- early Dapingian folding that is assigned to the Tumbaya phase. The second one is characterized by milonitic and cataclastic deformation in two plutons of the Cordón de Lila, a tectonic uplift and erosion of the magmatic arc and an unconformity during the Darriwilian and was assigned to the Guandacol phase.

Keywords : Tectonic phases Tumbaya; Guandacol; Ocloyic.

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